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Sample records for inbred mapping populations

  1. QTL mapping of fruit rot resistance to the plant pathogen Phytophthora capsici in a recombinant inbred line Capsicum annuum population.

    Science.gov (United States)

    Naegele, R P; Ashrafi, H; Hill, T A; Chin-Wo, S Reyes; Van Deynze, A E; Hausbeck, M K

    2014-05-01

    Phytophthora capsici is an important pepper (Capsicum annuum) pathogen causing fruit and root rot, and foliar blight in field and greenhouse production. Previously, an F6 recombinant inbred line population was evaluated for fruit rot susceptibility. Continuous variation among lines and partial and isolate-specific resistance were found. In this study, Phytophthora fruit rot resistance was mapped in the same F6 population between Criollo del Morelos 334 (CM334), a landrace from Mexico, and 'Early Jalapeno' using a high-density genetic map. Isolate-specific resistance was mapped independently in 63 of the lines evaluated and the two parents. Heritability of the resistance for each isolate at 3 and 5 days postinoculation (dpi) was high (h(2) = 0.63 to 0.68 and 0.74 to 0.83, respectively). Significant additive and epistatic quantitative trait loci (QTL) were identified for resistance to isolates OP97 and 13709 (3 and 5 dpi) and 12889 (3 dpi only). Mapping of fruit traits showed potential linkage with few disease resistance QTL. The partial fruit rot resistance from CM334 suggests that this may not be an ideal source for fruit rot resistance in pepper.

  2. Development of a near-isogenic line population of Arabidopsis thaliana and comparison of mapping power with a recombinant inbred line population.

    Science.gov (United States)

    Keurentjes, Joost J B; Bentsink, Leónie; Alonso-Blanco, Carlos; Hanhart, Corrie J; Blankestijn-De Vries, Hetty; Effgen, Sigi; Vreugdenhil, Dick; Koornneef, Maarten

    2007-02-01

    In Arabidopsis recombinant inbred line (RIL) populations are widely used for quantitative trait locus (QTL) analyses. However, mapping analyses with this type of population can be limited because of the masking effects of major QTL and epistatic interactions of multiple QTL. An alternative type of immortal experimental population commonly used in plant species are sets of introgression lines. Here we introduce the development of a genomewide coverage near-isogenic line (NIL) population of Arabidopsis thaliana, by introgressing genomic regions from the Cape Verde Islands (Cvi) accession into the Landsberg erecta (Ler) genetic background. We have empirically compared the QTL mapping power of this new population with an already existing RIL population derived from the same parents. For that, we analyzed and mapped QTL affecting six developmental traits with different heritability. Overall, in the NIL population smaller-effect QTL than in the RIL population could be detected although the localization resolution was lower. Furthermore, we estimated the effect of population size and of the number of replicates on the detection power of QTL affecting the developmental traits. In general, population size is more important than the number of replicates to increase the mapping power of RILs, whereas for NILs several replicates are absolutely required. These analyses are expected to facilitate experimental design for QTL mapping using these two common types of segregating populations.

  3. Genome-wide QTL mapping for wheat processing quality parameters in a Gaocheng 8901/Zhoumai 16 recombinant inbred line population

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    Hui Jin

    2016-07-01

    Full Text Available Dough rheological and starch pasting properties play an important role in determining processing quality in bread wheat (Triticum aestivum L.. In the present study, a recombinant inbred line (RIL population derived from a Gaocheng 8901/Zhoumai 16 cross grown in three environments was used to identify quantitative trait loci (QTLs for dough rheological and starch pasting properties evaluated by Mixograph, Rapid Visco-Analyzer (RVA and Mixolab parameters using 90K and 660K single nucleotide polymorphism (SNP chip assays. A high-density linkage map constructed with 46,961 polymorphic SNP markers from the wheat 90K and 660K SNP assays spanned a total length of 4,121 cM, with an average chromosome length of 196.2 cM and marker density of 0.09 cM/marker; 6,596 new SNP markers were anchored to the bread wheat linkage map, with 1,046 and 5,550 markers from the 90K and 660K SNP assays, respectively. Composite interval mapping identified 119 additive QTLs on 20 chromosomes except 4D; among them, 15 accounted for more than 10% of the phenotypic variation across two or three environments. Twelve QTLs for Mixograph parameters, 17 for RVA parameters and 55 for Mixolab parameters were new. Eleven QTL clusters were identified. The closely linked SNP markers can be used in marker-assisted wheat breeding in combination with the Kompetitive Allele Specific PCR (KASP technique for improvement of processing quality in bread wheat.

  4. Genetic loci mapping for ear axis weight using recombinant inbred ...

    African Journals Online (AJOL)

    Ear axis weight (EAW) is one of the important agronomic traits in maize (Zea mays L.), related to yield. To understand its genetic basis, a recombinant inbred line (RIL) population, derived from the cross Mo17 × Huangzao4, was used for quantitative trait locus mapping (QTL) for EAW under high and low nitrogen (N) regimes.

  5. Variability among inbred lines and RFLP mapping of sunflower isozymes

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    Carrera Alicia D.

    2002-01-01

    Full Text Available Eight isozyme systems were used in this study: acid phosphatase (ACP, alcohol dehydrogenase (ADH, esterase (EST, glutamate dehydrogenase (GDH, malate dehydrogenase (MDH, phosphoglucoisomerase (PGI, 6-phosphogluconate dehydrogenase (PGD, and phosphoglucomutase (PGM. The polymorphism of these enzyme systems was studied in 25 elite inbred lines. A total of 19 loci were identified, but only eight of them were polymorphic in the germplasm tested. The polymorphic index for the eight informative markers ranged from 0.08 to 0.57, with a mean value of 0.36. Five isozyme loci were mapped in F2:3 populations with existing RFLP data. Est-1, Gdh-2 and Pgi-2 were mapped to linkage groups 3, 14 and 9, respectively. As in previous reports, an ACP locus and a PGD locus were found to be linked, both located in linkage group 2 of the public sunflower map.

  6. Genetic analysis of morphological traits in a new, versatile, rapid-cycling Brassica rapa recombinant inbred line population

    NARCIS (Netherlands)

    Bagheri, H.; El-Soda, M.; Oorschot, van I.; Hanhart, C.J.; Bonnema, A.B.; Jansen-van den Bosch, T.; Mank, R.; Keurentjes, J.J.B.; Meng, L.; Wu, Jian; Koornneef, M.; Aarts, M.G.M.

    2012-01-01

    A recombinant inbred line (RIL) population was produced based on a wide cross between the rapid-cycling and self-compatible genotypes L58, a Caixin vegetable type, and R-o-18, a yellow sarson oil type. A linkage map based on 160 F7 lines was constructed using 100 Single nucleotide polymorphisms

  7. Joint QTL analyses for partial resistance to Phytophthora sojae using six nested inbred populations with heterogeneous conditions

    Science.gov (United States)

    Partial resistance to Phytophthora sojae in soybean is controlled by multiple quantitative trait loci (QTL). With traditional QTL mapping approaches, power to detect these QTL, frequently of small effect, can be limited by population size. Joint linkage QTL analysis of nested recombinant inbred li...

  8. Fine Mapping of QTLs for Ascochyta Blight Resistance in Pea Using Heterogeneous Inbred Families

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    Ambuj B. Jha

    2017-05-01

    Full Text Available Ascochyta blight (AB is an important disease of pea which can cause severe grain yield loss under wet conditions. In our previous study, we identified two quantitative trait loci (QTLs abIII-1 and abI-IV-2 for AB resistance and these QTLs were consistent across locations and/or years in an inter-specific pea population (PR-19 developed from a cross between Alfetta (Pisum sativum and P651 (P. fulvum. The objectives of this study were to fine map the abIII-1 and abI-IV-2 QTLs using a high density single nucleotide polymorphism (SNP-based genetic linkage map and analyze identified markers in heterogeneous inbred family (HIF populations. Selective genotyping of 51 PR-19 recombinant inbred lines was performed using genotyping-by-sequencing (GBS and the resulting high density genetic linkage map was used to identify eight new SNP markers within the abI-IV-2 QTL, whereas no additional SNPs were identified within the abIII-1 QTL. Two HIF populations HIF-224 (143 lines and HIF-173 (126 lines were developed from F6 RILs PR-19-224 and PR-19-173, respectively. The HIF populations evaluated under field conditions in 2015 and 2016 showed a wide range of variation for reaction to AB resistance. Lodging score had significant positive (P < 0.001 correlation with AB scores. HIFs were genotyped using SNP markers within targeted QTLs. The genotypic and phenotypic data of the HIFs were used to identify two new QTLs, abI-IV-2.1 and abI-IV-2.2 for AB resistance within the abI-IV-2 QTL. These QTLs individually explained 5.5 to 14% of the total phenotypic variation. Resistance to lodging was also associated with these two QTLs. Identified SNP markers will be useful in marker assisted selection for development of pea cultivars with improved AB resistance.

  9. The Genetic Basis of Plant Architecture in 10 Maize Recombinant Inbred Line Populations.

    Science.gov (United States)

    Pan, Qingchun; Xu, Yuancheng; Li, Kun; Peng, Yong; Zhan, Wei; Li, Wenqiang; Li, Lin; Yan, Jianbing

    2017-10-01

    Plant architecture is a key factor affecting planting density and grain yield in maize ( Zea mays ). However, the genetic mechanisms underlying plant architecture in diverse genetic backgrounds have not been fully addressed. Here, we performed a large-scale phenotyping of 10 plant architecture-related traits and dissected the genetic loci controlling these traits in 10 recombinant inbred line populations derived from 14 diverse genetic backgrounds. Nearly 800 quantitative trait loci (QTLs) with major and minor effects were identified as contributing to the phenotypic variation of plant architecture-related traits. Ninety-two percent of these QTLs were detected in only one population, confirming the diverse genetic backgrounds of the mapping populations and the prevalence of rare alleles in maize. The numbers and effects of QTLs are positively associated with the phenotypic variation in the population, which, in turn, correlates positively with parental phenotypic and genetic variations. A large proportion (38.5%) of QTLs was associated with at least two traits, suggestive of the frequent occurrence of pleiotropic loci or closely linked loci. Key developmental genes, which previously were shown to affect plant architecture in mutant studies, were found to colocalize with many QTLs. Five QTLs were further validated using the segregating populations developed from residual heterozygous lines present in the recombinant inbred line populations. Additionally, one new plant height QTL, qPH3 , has been fine-mapped to a 600-kb genomic region where three candidate genes are located. These results provide insights into the genetic mechanisms controlling plant architecture and will benefit the selection of ideal plant architecture in maize breeding. © 2017 American Society of Plant Biologists. All Rights Reserved.

  10. An Integrated in Silico Gene Mapping Strategy in Inbred Mice

    OpenAIRE

    Cervino, Alessandra C. L.; Darvasi, Ariel; Fallahi, Mohammad; Mader, Christopher C.; Tsinoremas, Nicholas F.

    2007-01-01

    In recent years in silico analysis of common laboratory mice has been introduced and subsequently applied, in slightly different ways, as a methodology for gene mapping. Previously we have demonstrated some limitation of the methodology due to sporadic genetic correlations across the genome. Here, we revisit the three main aspects that affect in silico analysis. First, we report on the use of marker maps: we compared our existing 20,000 SNP map to the newly released 140,000 SNP map. Second, w...

  11. Inbreeding depression in maize populations and its effects on the obtention of promising inbred lines

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    Deoclecio Domingos Garbuglio

    2017-10-01

    Full Text Available Inbreeding can potentially be used for the development of inbred lines containing alleles of interest, but the genetic causes that control inbreeding depression are not completely known, and there are few studies found in the literature. The present study aimed to obtain estimates of inbreeding depression for eight traits in seven tropical maize populations, analyze the effects of inbreeding over generations and environments, and predict the behavior of inbred lines in future generation S? through linear regression methods. It was found that regardless of the base population used, prediction values could vary when the model was based on only 2 generations of inbreeding due to the environmental component. The influence of the environment in this type of study could be reduced when considering 3 generations of inbreeding, allowing greater precision in predicting the phenotypes of inbred lines. The use of linear regression was effective for inbred line prediction for the different agronomic traits evaluated. The use of 3 levels of inbreeding minimizes the effects of the environmental component in inbred line prediction for grain yield. GO-S was the most promising population for inbred line extraction.

  12. An integrated in silico gene mapping strategy in inbred mice.

    Science.gov (United States)

    Cervino, Alessandra C L; Darvasi, Ariel; Fallahi, Mohammad; Mader, Christopher C; Tsinoremas, Nicholas F

    2007-01-01

    In recent years in silico analysis of common laboratory mice has been introduced and subsequently applied, in slightly different ways, as a methodology for gene mapping. Previously we have demonstrated some limitation of the methodology due to sporadic genetic correlations across the genome. Here, we revisit the three main aspects that affect in silico analysis. First, we report on the use of marker maps: we compared our existing 20,000 SNP map to the newly released 140,000 SNP map. Second, we investigated the effect of varying strain numbers on power to map QTL. Third, we introduced a novel statistical approach: a cladistic analysis, which is well suited for mouse genetics and has increased flexibility over existing in silico approaches. We have found that in our examples of complex traits, in silico analysis by itself does fail to uniquely identify quantitative trait gene (QTG)-containing regions. However, when combined with additional information, it may significantly help to prioritize candidate genes. We therefore recommend using an integrated work flow that uses other genomic information such as linkage regions, regions of shared ancestry, and gene expression information to obtain a list of candidate genes from the genome.

  13. Genetic architecture of rind penetrometer resistance in two maize recombinant inbred line populations.

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    Li, Kun; Yan, Jianbing; Li, Jiansheng; Yang, Xiaohong

    2014-06-03

    Maize (Zea Mays L.) is one of the most important cereal crops worldwide and provides food for billions of people. Stalk lodging can greatly undermine the standability of maize plants and therefore decrease crop yields. Rind penetrometer resistance is an effective and reliable method for evaluating maize stalk strength, which is highly correlated with stalk lodging resistance. In this study, two recombinant inbred line populations were constructed from crosses between the H127R and Chang7-2 lines, and between the B73 and By804 lines. We genotyped these two populations and their parents using 3,072 single nucleotide polymorphism markers and performed phenotypic assessment of rind penetrometer resistance in multiple environments to dissect the genetic architecture of rind penetrometer resistance in maize. Based on two linkage maps of 1,397.1 and 1,600.4 cM with average interval of 1.7 and 2.1 cM between adjacent makers, respectively, seven quantitative trait loci (QTL) for rind penetrometer resistance were detected in the two recombinant inbred line populations. These QTL were distributed in seven genomic regions, and each accounted for 4.4-18.9% of the rind penetrometer resistance variation. The QTL with the largest effect on rind penetrometer resistance, qRPR3-1, was located on chromosome 3 with the flanking markers PZE-103123325 and SYN23245. This locus was further narrowed down to a 3.1-Mb interval by haplotype analysis using high-density markers in the target region. Within this interval, four genes associated with the biosynthesis of cell wall components were considered as potential candidate genes for the rind penetrometer resistance effect. The inheritance of rind penetrometer resistance is rather complex. A few large-effect quantitative trait loci, together with a several minor-effect QTL, contributed to the phenotypic variation in rind penetrometer resistance in the two recombinant inbred line populations that were examined. A potential approach for

  14. Identification of exercise capacity QTL using association mapping in inbred mice.

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    Courtney, Sean M; Massett, Michael P

    2012-10-02

    There are large interindividual differences in exercise capacity. It is well established that there is a genetic basis for these differences. However, the genetic factors underlying this variation are undefined. Therefore, the purpose of this study was to identify novel putative quantitative trait loci (QTL) for exercise capacity by measuring exercise capacity in inbred mice and performing genome-wide association mapping. Exercise capacity, defined as run time and work, was assessed in male mice (n = 6) from 34 strains of classical and wild-derived inbred mice performing a graded treadmill test. Genome-wide association mapping was performed with an efficient mixed-model association (EMMA) algorithm to identify QTL. Exercise capacity was significantly different across strains. Run time varied by 2.7-fold between the highest running strain (C58/J) and the lowest running strain (A/J). These same strains showed a 16.5-fold difference in work. Significant associations were identified for exercise time on chromosomes 1, 2, 7, 11, and 13. The QTL interval on chromosome 2 (~168 Mb) contains one gene, Nfatc2, and overlaps with a suggestive QTL for training responsiveness in humans. These results provide phenotype data on the widest range of inbred strains tested thus far and indicate that genetic background significantly influences exercise capacity. Furthermore, the novel QTLs identified in the current study provide new targets for investigating the underlying mechanisms for variation in exercise capacity.

  15. QTL mapping for Mediterranean corn borer resistance in European flint germplasm using recombinant inbred lines

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    Santiago Rogelio

    2010-03-01

    Full Text Available Abstract Background Ostrinia nubilalis (ECB and Sesamia nonagrioides (MCB are two maize stem borers which cause important losses in temperate maize production, but QTL analyses for corn borer resistance were mostly restricted to ECB resistance and maize materials genetically related (mapping populations derived from B73. Therefore, the objective of this work was to identify and characterize QTLs for MCB resistance and agronomic traits in a RILs population derived from European flint inbreds. Results Three QTLs were detected for stalk tunnel length at bins 1.02, 3.05 and 8.05 which explained 7.5% of the RILs genotypic variance. The QTL at bin 3.05 was co-located to a QTL related to plant height and grain humidity and the QTL at bin 8.05 was located near a QTL related to yield. Conclusions Our results, when compared with results from other authors, suggest the presence of genes involved in cell wall biosynthesis or fortification with effects on resistance to different corn borer species and digestibility for dairy cattle. Particularly, we proposed five candidate genes related to cell wall characteristics which could explain the QTL for stalk tunnelling in the region 3.05. However, the small proportion of genotypic variance explained by the QTLs suggest that there are also many other genes of small effect regulating MCB resistance and we conclude that MAS seems not promising for this trait. Two QTLs detected for stalk tunnelling overlap with QTLs for agronomic traits, indicating the presence of pleitropism or linkage between genes affecting resistance and agronomic traits.

  16. Quantitative Trait Loci in Inbred Lines

    NARCIS (Netherlands)

    Jansen, R.C.

    2001-01-01

    Quantitative traits result from the influence of multiple genes (quantitative trait loci) and environmental factors. Detecting and mapping the individual genes underlying such 'complex' traits is a difficult task. Fortunately, populations obtained from crosses between inbred lines are relatively

  17. Analysis of natural allelic variation in Arabidopsis using a multiparent recombinant inbred line population

    NARCIS (Netherlands)

    Huang, X.; Caldas Paulo, M.J.; Boer, M.P.; Effgen, S.; Keizer, P.; Koornneef, M.; Eeuwijk, van F.A.

    2011-01-01

    To exploit the diversity in Arabidopsis thaliana, eight founder accessions were crossed to produce six recombinant inbred line (RIL) subpopulations, together called an Arabidopsis multiparent RIL (AMPRIL) population. Founders were crossed pairwise to produce four F1 hybrids. These F1s were crossed

  18. Genetic dissection of maize plant architecture with an ultra-high density bin map based on recombinant inbred lines.

    Science.gov (United States)

    Zhou, Zhiqiang; Zhang, Chaoshu; Zhou, Yu; Hao, Zhuanfang; Wang, Zhenhua; Zeng, Xing; Di, Hong; Li, Mingshun; Zhang, Degui; Yong, Hongjun; Zhang, Shihuang; Weng, Jianfeng; Li, Xinhai

    2016-03-03

    Plant architecture attributes, such as plant height, ear height, and internode number, have played an important role in the historical increases in grain yield, lodging resistance, and biomass in maize (Zea mays L.). Analyzing the genetic basis of variation in plant architecture using high density QTL mapping will be of benefit for the breeding of maize for many traits. However, the low density of molecular markers in existing genetic maps has limited the efficiency and accuracy of QTL mapping. Genotyping by sequencing (GBS) is an improved strategy for addressing a complex genome via next-generation sequencing technology. GBS has been a powerful tool for SNP discovery and high-density genetic map construction. The creation of ultra-high density genetic maps using large populations of advanced recombinant inbred lines (RILs) is an efficient way to identify QTL for complex agronomic traits. A set of 314 RILs derived from inbreds Ye478 and Qi319 were generated and subjected to GBS. A total of 137,699,000 reads with an average of 357,376 reads per individual RIL were generated, which is equivalent to approximately 0.07-fold coverage of the maize B73 RefGen_V3 genome for each individual RIL. A high-density genetic map was constructed using 4183 bin markers (100-Kb intervals with no recombination events). The total genetic distance covered by the linkage map was 1545.65 cM and the average distance between adjacent markers was 0.37 cM with a physical distance of about 0.51 Mb. Our results demonstrated a relatively high degree of collinearity between the genetic map and the B73 reference genome. The quality and accuracy of the bin map for QTL detection was verified by the mapping of a known gene, pericarp color 1 (P1), which controls the color of the cob, with a high LOD value of 80.78 on chromosome 1. Using this high-density bin map, 35 QTL affecting plant architecture, including 14 for plant height, 14 for ear height, and seven for internode number were detected

  19. Joint Analysis of Near-Isogenic and Recombinant Inbred Line Populations Yields Precise Positional Estimates for Quantitative Trait Loci

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    Kristen L. Kump

    2010-11-01

    Full Text Available Data generated for initial quantitative trait loci (QTL mapping using recombinant inbred line (RIL populations are usually ignored during subsequent fine-mapping using near-isogenic lines (NILs. Combining both datasets would increase the number of recombination events sampled and generate better position and effect estimates. Previously, several QTL for resistance to southern leaf blight of maize were mapped in two RIL populations, each independently derived from a cross between the lines B73 and Mo17. In each case the largest QTL was in bin 3.04. Here, two NIL pairs differing for this QTL were derived and used to create two distinct F family populations that were assessed for southern leaf blight (SLB resistance. By accounting for segregation of the other QTL in the original RIL data, we were able to combine these data with the new genotypic and phenotypic data from the F families. Joint analysis yielded a narrower QTL support interval compared to that derived from analysis of any one of the data sets alone, resulting in the localization of the QTL to a less than 0.5 cM interval. Candidate genes identified within this interval are discussed. This methodology allows combined QTL analysis in which data from RIL populations is combined with data derived from NIL populations segregating for the same pair of alleles. It improves mapping resolution over the conventional approach with virtually no additional resources. Because data sets of this type are commonly produced, this approach is likely to prove widely applicable.

  20. Genetic Analysis and QTL Detection on Fiber Traits Using Two Recombinant Inbred Lines and Their Backcross Populations in Upland Cotton.

    Science.gov (United States)

    Shang, Lianguang; Wang, Yumei; Wang, Xiaocui; Liu, Fang; Abduweli, Abdugheni; Cai, Shihu; Li, Yuhua; Ma, Lingling; Wang, Kunbo; Hua, Jinping

    2016-09-08

    Cotton fiber, a raw natural fiber material, is widely used in the textile industry. Understanding the genetic mechanism of fiber traits is helpful for fiber quality improvement. In the present study, the genetic basis of fiber quality traits was explored using two recombinant inbred lines (RILs) and corresponding backcross (BC) populations under multiple environments in Upland cotton based on marker analysis. In backcross populations, no significant correlation was observed between marker heterozygosity and fiber quality performance and it suggested that heterozygosity was not always necessarily advantageous for the high fiber quality. In two hybrids, 111 quantitative trait loci (QTL) for fiber quality were detected using composite interval mapping, in which 62 new stable QTL were simultaneously identified in more than one environment or population. QTL detected at the single-locus level mainly showed additive effect. In addition, a total of 286 digenic interactions (E-QTL) and their environmental interactions [QTL × environment interactions (QEs)] were detected for fiber quality traits by inclusive composite interval mapping. QE effects should be considered in molecular marker-assisted selection breeding. On average, the E-QTL explained a larger proportion of the phenotypic variation than the main-effect QTL did. It is concluded that the additive effect of single-locus and epistasis with few detectable main effects play an important role in controlling fiber quality traits in Upland cotton. Copyright © 2016 Shang et al.

  1. Genetic analysis of morphological traits in a new, versatile, rapid-cycling Brassica rapa recombinant inbred line population

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    Hedayat eBagheri

    2012-08-01

    Full Text Available A recombinant inbred line (RIL population was produced based on a wide cross between the rapid-cycling and self-compatible genotypes L58, a Caixin vegetable type, and R-o-18, a yellow sarson oil type. A linkage map based on 160 F7 lines was constructed using 100 SNP, 130 AFLP®, 27 InDel and 13 publicly available SSR markers. The map covers a total length of 1150 cM with an average resolution of 4.3 cM/marker. To demonstrate the versatility of this new population, 17 traits, related to plant architecture and seed characteristics, were subjected to QTL analysis. A total of 47 QTLs were detected, each explaining between 6 to 54% of the total phenotypic variance for the concerned trait. The genetic analysis shows that this population is a useful new tool for analyzing genetic variation for interesting traits in B. rapa, and for further exploitation of the recent availability of the B. rapa whole genome sequence for gene cloning and gene function analysis.

  2. Large-scale in silico mapping of complex quantitative traits in inbred mice.

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    Pengyuan Liu

    2007-07-01

    Full Text Available Understanding the genetic basis of common disease and disease-related quantitative traits will aid in the development of diagnostics and therapeutics. The processs of gene discovery can be sped up by rapid and effective integration of well-defined mouse genome and phenome data resources. We describe here an in silico gene-discovery strategy through genome-wide association (GWA scans in inbred mice with a wide range of genetic variation. We identified 937 quantitative trait loci (QTLs from a survey of 173 mouse phenotypes, which include models of human disease (atherosclerosis, cardiovascular disease, cancer and obesity as well as behavioral, hematological, immunological, metabolic, and neurological traits. 67% of QTLs were refined into genomic regions <0.5 Mb with approximately 40-fold increase in mapping precision as compared with classical linkage analysis. This makes for more efficient identification of the genes that underlie disease. We have identified two QTL genes, Adam12 and Cdh2, as causal genetic variants for atherogenic diet-induced obesity. Our findings demonstrate that GWA analysis in mice has the potential to resolve multiple tightly linked QTLs and achieve single-gene resolution. These high-resolution QTL data can serve as a primary resource for positional cloning and gene identification in the research community.

  3. Allelic expression changes in Medaka (Oryzias latipes hybrids between inbred strains derived from genetically distant populations.

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    Yasuhiko Murata

    Full Text Available Variations in allele expressions between genetically distant populations are one of the most important factors which affects their morphological and physiological variations. These variations are caused by natural mutations accumulated in their habitats. It has been reported that allelic expression differences in the hybrids of genetically distant populations are different from parental strains. In that case, there is a possibility that allelic expression changes lead to novel phenotypes in hybrids. Based on genomic information of the genetically distant populations, quantification and comparison of allelic expression changes make importance of regulatory sequences (cis-acting factors or upstream regulatory factors (trans-acting modulators for these changes clearer. In this study, we focused on two Medaka inbred strains, Hd-rR and HNI, derived from genetically distant populations and their hybrids. They are highly polymorphic and we can utilize whole-genome information. To analyze allelic expression changes, we established a method to quantify and compare allele-specific expressions of 11 genes between the parental strains and their reciprocal hybrids. In intestines of reciprocal hybrids, allelic expression was either similar or different in comparison with the parental strains. Total expressions in Hd-rR and HNI were tissue-dependent in the case of HPRT1, with high up-regulation of Hd-rR allele expression in liver. The proportion of genes with differential allelic expression in Medaka hybrids seems to be the same as that in other animals, despite the high SNP rate in the genomes of the two inbred strains. It is suggested that each tissue of the strain difference in trans-acting modulators is more important than polymorphisms in cis-regulatory sequences in producing the allelic expression changes in reciprocal hybrids.

  4. QTL delineation for five fiber quality traits based on an intra-specific Gossypium hirsutum L. recombinant inbred line population.

    Science.gov (United States)

    Jia, Xiaoyun; Wang, Hantao; Pang, Chaoyou; Ma, Qifeng; Su, Junji; Wei, Hengling; Song, Meizhen; Fan, Shuli; Yu, Shuxun

    2018-02-08

    Gossypium hirsutum L. is the most important fiber crop worldwide and contributes to more than 95% of global cotton production. Marker-assisted selection (MAS) is an effective approach for improving fiber quality, and quantitative trait loci (QTL) mapping of fiber quality traits is important for cotton breeding. In this study, a permanent intra-specific recombinant inbred line (RIL) population containing 137 families was used for fiber quality testing. Based on a previously reported high-density genetic map with an average marker distance of 0.63 cM, 186 additive QTLs were obtained for five fiber quality traits over five consecutive years, including 39 for fiber length (FL), 36 for fiber strength (FS), 50 for fiber uniformity (FU), 33 for micronaire (MC) and 28 for fiber elongation (FE). Three stable QTLs, qMC-A4-1, qMC-D2-3 and qFS-D9-1, were detected in four datasets, and another eight stable QTLs, qMC-A4-2, qMC-D11-2, qFU-A9-1, qFU-A10-4, qFS-D11-1, qFL-D9-2, qFL-D11-1 and qFE-A3-2, were detected in three datasets. The annotated genes in these 11 stable QTLs were collected, and these genes included many transcription factors with functions during fiber development. 33 QTL coincidence regions were found, and these involved nearly half of the total QTLs. Four chromosome regions containing at least 6 QTLs were promising for fine mapping. In addition, 41 pairs of epistatic QTLs (e-QTLs) were screened, including 6 for FL, 30 for FS, 2 for FU and 3 for MC. The identification of stable QTLs adds valuable information for further QTL fine mapping and gene positional cloning for fiber quality genetic detection and provides useful markers for further molecular breeding in enhancing fiber quality.

  5. Genetic loci mapping for ear axis weight using recombinant inbred line

    African Journals Online (AJOL)

    Jane

    2011-08-08

    Aug 8, 2011 ... Ear axis weight (EAW) is one of the important agronomic traits in maize (Zea mays L.), related to yield. To understand its genetic ... but the studies on using different N environments to map. QTL for maize EAW were not .... Mapping QTLs for grain yield and yield components under high and low phosphorus ...

  6. Proteomic Mapping of Dental Enamel Matrix from Inbred Mouse Strains: Unraveling Potential New Players in Enamel.

    Science.gov (United States)

    Lima Leite, Aline; Silva Fernandes, Mileni; Charone, Senda; Whitford, Gary Milton; Everett, Eric T; Buzalaf, Marília Afonso Rabelo

    2018-01-01

    Enamel formation is a complex 2-step process by which proteins are secreted to form an extracellular matrix, followed by massive protein degradation and subsequent mineralization. Excessive systemic exposure to fluoride can disrupt this process and lead to a condition known as dental fluorosis. The genetic background influences the responses of mineralized tissues to fluoride, such as dental fluorosis, observed in A/J and 129P3/J mice. The aim of the present study was to map the protein profile of enamel matrix from A/J and 129P3/J strains. Enamel matrix samples were obtained from A/J and 129P3/J mice and analyzed by 2-dimensional electrophoresis and liquid chromatography coupled with mass spectrometry. A total of 120 proteins were identified, and 7 of them were classified as putative uncharacterized proteins and analyzed in silico for structural and functional characterization. An interesting finding was the possibility of the uncharacterized sequence Q8BIS2 being an enzyme involved in the degradation of matrix proteins. Thus, the results provide a comprehensive view of the structure and function for putative uncharacterized proteins found in the enamel matrix that could help to elucidate the mechanisms involved in enamel biomineralization and genetic susceptibility to dental fluorosis. © 2018 S. Karger AG, Basel.

  7. Identification of candidate genes associated with cell wall digestibility and eQTL (expression quantitative trait loci analysis in a Flint × Flint maize recombinant inbred line population

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    Wenzel Gerhard

    2007-01-01

    Full Text Available Abstract Background Cell-wall digestibility is the major target for improving the feeding value of forage maize. An understanding of the molecular basis for cell-wall digestibility is crucial towards breeding of highly digestible maize. Results 865 candidate ESTs for cell-wall digestibility were selected according to the analysis of expression profiles in 1 three sets of brown-midrib isogenic lines in the genetic background of inbreds 1332 (1332 and 1332 bm3, 5361 (5361 and 5361 bm3, and F2 (F2, F2 bm1, F2 bm2, and F2 bm3, 2 the contrasting extreme lines of FD (Flint × Dent, AS08 × AS 06, DD1 (Dent × Dent, AS11 × AS09, and DD2 (Dent × Dent, AS29 × AS30 mapping populations, and 3 two contrasting isogenic inbreds, AS20 and AS21. Out of those, 439 ESTs were assembled on our "Forage Quality Array", a small microarray specific for cell wall digestibility related experiments. Transcript profiles of 40 lines of a Flint × Flint population were monitored using the Forage Quality Array, which were contrasting for cell wall digestibility. Using t-tests (p Conclusion 102 candidate genes for cell-wall digestibility were validated by genetical genomics approach. Although the cDNA array highlights gene types (the tested gene and any close family members, trans-acting factors or metabolic bottlenecks seem to play the major role in controlling heritable variation of gene expression related to cell-wall digestibility, since no in silico mapped ESTs were in the same location as their own eQTL. Transcriptional variation was generally found to be oligogenic rather than monogenic inherited due to only 26% ESTs detected a single eQTL in the present study. One eQTL hotspot was co-localized with cell wall digestibility related QTL cluster on bins 3.05, implying that in this case the gene(s underlying QTL and eQTL are identical. As the field of genetical genomics develops, it is expected to significantly improve our knowledge about complex traits, such as cell

  8. Construction of a genetic linkage map in Lilium using a RIL mapping population based on SRAP marker

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    Chen Li-Jing

    2015-01-01

    Full Text Available A genetic linkage map of lily was constructed using RILs (recombinant inbred lines population of 180 individuals. This mapping population was developed by crossing Raizan No.1 (Formolongo and Gelria (Longiflomm cultivars through single-seed descent (SSD. SRAPs were generated by using restriction enzymes EcoRI in combination with either MseI. The resulting products were separated by electrophoresis on 6% denaturing polyacrylamide gel and visualized by silver staining. The segregation of each marker and linkage analysis was done using the program Mapmaker3.0. With 50 primer pairs, a total of 189 parental polymorphic bands were detected and 78 were used for mapping. The total map length was 2,135.5 cM consisted of 16 linkage groups. The number of markers in the linkage groups varied from 1 to 12. The length of linkage groups was range from 11.2 cM to 425.9 cM and mean marker interval distance range from 9.4 cM to 345.4 cM individually. The mean marker interval distance between markers was 27.4 cM. The map developed in the present study was the first sequence-related amplified polymorphism markers map of lily constructed with recombinant inbred lines, it could be used for genetic mapping and molecular marker assisted breeding and quantitative trait locus mapping of Lilium.

  9. RNA-Seq using bulked recombinant inbred line populations uncovers the importance of brassinosteroid for seed longevity after priming treatments.

    Science.gov (United States)

    Sano, Naoto; Kim, June-Sik; Onda, Yoshihiko; Nomura, Takahito; Mochida, Keiichi; Okamoto, Masanori; Seo, Mitsunori

    2017-08-14

    Seed priming is a commercially used technique for improving seed performance including germination. However, the treatment sometimes reduces seed longevity as a side effect, limiting the storable period or longevity of the seeds. To overcome this problem, molecular mechanisms involved in the loss of seed longevity during priming were analyzed using natural variations of Arabidopsis thaliana. We found that the Est-1 accession retained longevity for longer after priming compared to the reference accession Col-0. QTL analysis using 279 recombinant inbred lines (RILs) derived from the Est-1 × Col-0 detected three QTL regions associated with the loss of seed longevity during priming. Bulked transcriptome analysis (RNA-Seq with bulked RIL populations) revealed that genes related to brassinosteroid (BR) biosynthesis/signaling and cell wall modification were highly expressed in primed seeds with shorter longevity. After priming, BR-deficient mutants cyp85a1/a2 and det2 showed significantly longer longevity than the wild type (WT). Moreover, tetrazolium staining indicated that mutant seed coats were less permeable after priming than those of WT. We suggest that the loss of seed longevity in primed seed is due to increased seed coat permeability, which is positively regulated, at least partly, via BR signaling.

  10. What the Inbred Scandinavian Wolf Population Tells Us about the Nature of Conservation.

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    Jannikke Räikkönen

    Full Text Available The genetic aspects of population health are critical, but frequently difficult to assess. Of concern has been the genetic constitution of Scandinavian wolves (Canis lupus, which represent an important case in conservation. We examined the incidence of different congenital anomalies for 171 Scandinavian wolves, including the immigrant founder female, born during a 32-year period between 1978 and 2010. The incidence of anomalies rose from 13% to 40% throughout the 32-year study period. Our ability to detect this increase was likely facilitated by having considered multiple kinds of anomaly. Many of the found anomalies are likely associated with inbreeding or some form of genetic deterioration. These observations have implications for understanding the conservation needs of Scandinavian wolves. Moreover, these observations and the history of managing Scandinavian wolves focus attention on a broader question, whether conservation is merely about avoiding extinction of remnant populations, or whether conservation also entails maintaining genetic aspects of population health.

  11. Radiation tumorigenesis in inbred laboratory animals and cancer risks in irradiated human populations. Two widely different problems

    International Nuclear Information System (INIS)

    Walinder, G.

    1978-01-01

    The mammal has efficient defence mechanisms against the development of tumours. These mechanisms are successively deteriorated by ionizing radiation when the dose increases beyond certain 'borderline levels'. Consequently, most animal strains demonstrate a bi-phasic dose-tumour relationship with a low-dose limb, the slope of which cannot be distinguished from zero, and a high-dose limb that increases with increasing doses. There are four or five exceptions to this 'rule' but in most of these cases the probable reasons for the deviations are known. Some human tumours as observed in epidemiological investigations do not demonstrate a similar clearly bi-phasic dose response. In all probability, this discrepancy does not reflect a higher susceptibility to radiation-induced tumours in man compared with other mammals. It is rather a consequence of a greater statistical variation in radiosensitivity in heterogeneous human populations than among inbred animals living standardized conditions. Accordingly, when maximum permissible dose levels are to be determined one should extrapolate from epidemiological data. Furthermore, these extrapolations should be linear if the data do not clearly deviate from a straight line, and if there are no scientific reasons to assume that a threshold exists. This formal method would not produce a biological description of what may happen in the low-dose area but rather an upper risk limit for the population studied. The real low-dose risk cannot be known. For the same pragmatic reason other radiological or non-radiological risks should be determined in the same manner, particularly when risks are to be compared. (author)

  12. QTL Mapping of Combining Ability and Heterosis of Agronomic Traits in Rice Backcross Recombinant Inbred Lines and Hybrid Crosses

    Science.gov (United States)

    Luo, Junyuan; Wang, Peng; Yu, Sibin; Mou, Tongmin; Zheng, Xingfei; Hu, Zhongli

    2012-01-01

    Background Combining ability effects are very effective genetic parameters in deciding the next phase of breeding programs. Although some breeding strategies on the basis of evaluating combining ability have been utilized extensively in hybrid breeding, little is known about the genetic basis of combining ability. Combining ability is a complex trait that is controlled by polygenes. With the advent and development of molecular markers, it is feasible to evaluate the genetic bases of combining ability and heterosis of elite rice hybrids through QTL analysis. Methodology/Principal Findings In the present study, we first developed a QTL-mapping method for dissecting combining ability and heterosis of agronomic traits. With three testcross populations and a BCRIL population in rice, biometric and QTL analyses were conducted for ten agronomic traits. The significance of general combining ability and special combining ability for most of the traits indicated the importance of both additive and non-additive effects on expression levels. A large number of additive effect QTLs associated with performance per se of BCRIL and general combining ability, and dominant effect QTLs associated with special combining ability and heterosis were identified for the ten traits. Conclusions/Significance The combining ability of agronomic traits could be analyzed by the QTL mapping method. The characteristics revealed by the QTLs for combining ability of agronomic traits were similar with those by multitudinous QTLs for agronomic traits with performance per se of BCRIL. Several QTLs (1–6 in this study) were identified for each trait for combining ability. It demonstrated that some of the QTLs were pleiotropic or linked tightly with each other. The identification of QTLs responsible for combining ability and heterosis in the present study provides valuable information for dissecting genetic basis of combining ability. PMID:22291881

  13. QTL mapping of combining ability and heterosis of agronomic traits in rice backcross recombinant inbred lines and hybrid crosses.

    Directory of Open Access Journals (Sweden)

    Zhen Qu

    Full Text Available BACKGROUND: Combining ability effects are very effective genetic parameters in deciding the next phase of breeding programs. Although some breeding strategies on the basis of evaluating combining ability have been utilized extensively in hybrid breeding, little is known about the genetic basis of combining ability. Combining ability is a complex trait that is controlled by polygenes. With the advent and development of molecular markers, it is feasible to evaluate the genetic bases of combining ability and heterosis of elite rice hybrids through QTL analysis. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we first developed a QTL-mapping method for dissecting combining ability and heterosis of agronomic traits. With three testcross populations and a BCRIL population in rice, biometric and QTL analyses were conducted for ten agronomic traits. The significance of general combining ability and special combining ability for most of the traits indicated the importance of both additive and non-additive effects on expression levels. A large number of additive effect QTLs associated with performance per se of BCRIL and general combining ability, and dominant effect QTLs associated with special combining ability and heterosis were identified for the ten traits. CONCLUSIONS/SIGNIFICANCE: The combining ability of agronomic traits could be analyzed by the QTL mapping method. The characteristics revealed by the QTLs for combining ability of agronomic traits were similar with those by multitudinous QTLs for agronomic traits with performance per se of BCRIL. Several QTLs (1-6 in this study were identified for each trait for combining ability. It demonstrated that some of the QTLs were pleiotropic or linked tightly with each other. The identification of QTLs responsible for combining ability and heterosis in the present study provides valuable information for dissecting genetic basis of combining ability.

  14. Multiparent intercross populations in analysis of quantitative traits

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 91; Issue 1 ... gene mapping; QTL analysis; multiparent intercross population; MAGIC; AMPRIL; association mapping. ... In conventional QTL analysis, F2, backcross populations, recombinant inbred lines, backcross inbred lines and double haploids from biparental crosses are ...

  15. Identification of stable quantitative trait loci (QTLs) for fiber quality traits across multiple environments in Gossypium hirsutum recombinant inbred line population.

    Science.gov (United States)

    Jamshed, Muhammad; Jia, Fei; Gong, Juwu; Palanga, Koffi Kibalou; Shi, Yuzhen; Li, Junwen; Shang, Haihong; Liu, Aiying; Chen, Tingting; Zhang, Zhen; Cai, Juan; Ge, Qun; Liu, Zhi; Lu, Quanwei; Deng, Xiaoying; Tan, Yunna; Or Rashid, Harun; Sarfraz, Zareen; Hassan, Murtaza; Gong, Wankui; Yuan, Youlu

    2016-03-08

    The identification of quantitative trait loci (QTLs) that are stable and consistent across multiple environments and populations plays an essential role in marker-assisted selection (MAS). In the present study, we used 28,861 simple sequence repeat (SSR) markers, which included 12,560 Gossypium raimondii (D genome) sequence-based SSR markers to identify polymorphism between two upland cotton strains 0-153 and sGK9708. A total of 851 polymorphic primers were finally selected and used to genotype 196 recombinant inbred lines (RIL) derived from a cross between 0 and 153 and sGK9708 and used to construct a linkage map. The RIL population was evaluated for fiber quality traits in six locations in China for five years. Stable QTLs identified in this intraspecific cross could be used in future cotton breeding program and with fewer obstacles. The map covered a distance of 4,110 cM, which represents about 93.2 % of the upland cotton genome, and with an average distance of 5.2 cM between adjacent markers. We identified 165 QTLs for fiber quality traits, of which 47 QTLs were determined to be stable across multiple environments. Most of these QTLs aggregated into clusters with two or more traits. A total of 30 QTL clusters were identified which consisted of 103 QTLs. Sixteen clusters in the At sub-genome comprised 44 QTLs, whereas 14 clusters in the Dt sub-genome that included 59 QTLs for fiber quality were identified. Four chromosomes, including chromosome 4 (c4), c7, c14, and c25 were rich in clusters harboring 5, 4, 5, and 6 clusters respectively. A meta-analysis was performed using Biomercator V4.2 to integrate QTLs from 11 environmental datasets on the RIL populations of the above mentioned parents and previous QTL reports. Among the 165 identified QTLs, 90 were identified as common QTLs, whereas the remaining 75 QTLs were determined to be novel QTLs. The broad sense heritability estimates of fiber quality traits were high for fiber length (0.93), fiber strength (0

  16. Mapping of imprinted quantitative trait loci using immortalized F2 populations.

    Directory of Open Access Journals (Sweden)

    Yongxian Wen

    Full Text Available Mapping of imprinted quantitative trait loci (iQTLs is helpful for understanding the effects of genomic imprinting on complex traits in animals and plants. At present, the experimental designs and corresponding statistical methods having been proposed for iQTL mapping are all based on temporary populations including F2 and BC1, which can be used only once and suffer some other shortcomings respectively. In this paper, we propose a framework for iQTL mapping, including methods of interval mapping (IM and composite interval mapping (CIM based on conventional low-density genetic maps and point mapping (PM and composite point mapping (CPM based on ultrahigh-density genetic maps, using an immortalized F2 (imF2 population generated by random crosses between recombinant inbred lines or doubled haploid lines. We demonstrate by simulations that imF2 populations are very desirable and the proposed statistical methods (especially CIM and CPM are very powerful for iQTL mapping, with which the imprinting effects as well as the additive and dominance effects of iQTLs can be unbiasedly estimated.

  17. Quantitative trait loci underlying resistance to sudden death syndrome (SDS) in MD96-5722 by 'Spencer' recombinant inbred line population of soybean.

    Science.gov (United States)

    Anderson, J; Akond, M; Kassem, M A; Meksem, K; Kantartzi, S K

    2015-04-01

    The best way to protect yield loss of soybean [Glycine max (L.) Merr.] due to sudden death syndrome (SDS), caused by Fusarium virguliforme (Aoki, O'Donnel, Homma & Lattanzi), is the development and use of resistant lines. Mapping quantitative trait loci (QTL) linked to SDS help developing resistant soybean germplasm through molecular marker-assisted selection strategy. QTL for SDS presented herein are from a high-density SNP-based genetic linkage map of MD 96-5722 (a.k.a 'Monocacy') by 'Spencer' recombinant inbred line using SoySNP6K Illumina Infinium BeadChip genotyping array. Ninety-four F 5:7 lines were evaluated for 2 years (2010 and 2011) at two locations (Carbondale and Valmeyer) in southern Illinois, USA to identify QTL controlling SDS resistance using disease index (DX). Composite interval mapping identified 19 SDS controlling QTL which were mapped on 11 separate linkage group (LG) or chromosomes (Chr) out of 20 LG or Chr of soybean genome. Many of these significant QTL identified in one environment/year were confirmed in another year or environment, which suggests a common genetic effects and modes of the pathogen. These new QTL are useful sources for SDS resistance studies in soybean breeding, complementing previously reported loci.

  18. Strain-specific and recessive QTLs involved in the control of partial resistance to Fusarium oxysporum f. sp. melonis race 1.2 in a recombinant inbred line population of melon.

    Science.gov (United States)

    Perchepied, L; Dogimont, C; Pitrat, M

    2005-06-01

    Fusarium oxysporum f. sp. melonis (FOM) causes serious economic losses in melon (Cucumis melo L.). Two dominant resistance genes have been identified, Fom-1 and Fom-2, which provide resistance to races 0 and 2 and races 0 and 1, respectively, however FOM race 1.2 overcomes these resistance genes. A partial resistance to FOM race 1.2 that has been found in some Far East accessions is under polygenic control. A genetic map of melon was constructed to tag FOM race 1.2 resistance with DNA markers on a recombinant inbred line population derived from a cross between resistant (Isabelle) and susceptible (cv. Védrantais) lines. Artificial root inoculations on plantlets of this population using two strains, one that causes wilting (FOM 1.2w) and one that causes yellowing (FOM 1.2y), resulted in phenotypic and genotypic data that enabled the identification of nine quantitative trait loci (QTLs). These QTLs were detected on five linkage groups by composite interval mapping and explained between 41.9% and 66.4% of the total variation. Four digenic epistatic interactions involving seven loci were detected and increased the total phenotypic variation that was explained. Co-localizations between QTLs and resistance gene homologs or resistance genes, such as Fom-2 and Vat, were observed. A strain-specific QTL was detected, and some QTLs appeared to be recessive.

  19. Using gene expression databases for classical trait QTL candidate gene discovery in the BXD recombinant inbred genetic reference population: Mouse forebrain weight

    Directory of Open Access Journals (Sweden)

    Zhou Jianhua

    2008-09-01

    Full Text Available Abstract Background Successful strategies for QTL gene identification benefit from combined experimental and bioinformatic approaches. Unique design aspects of the BXD recombinant inbred line mapping panel allow use of archived gene microarray expression data to filter likely from unlikely candidates. This prompted us to propose a simple five-filter protocol for candidate nomination. To filter more likely from less likely candidates, we required candidate genes near to the QTL to have mRNA abundance that correlated with the phenotype among the BXD lines as well as differed between the parental lines C57BL/6J and DBA/2J. We also required verification of mRNA abundance by an independent method, and finally we required either differences in protein levels or confirmed DNA sequence differences. Results QTL mapping of mouse forebrain weight in 34 BXD RI lines found significant association on chromosomes 1 and 11, with each C57BL/6J allele increasing weight by more than half a standard deviation. The intersection of gene lists that were within ± 10 Mb of the strongest associated location, that had forebrain mRNA abundance correlated with forebrain weight among the BXD, and that had forebrain mRNA abundance differing between C57BL/6J and DBA/2J, produced two candidates, Tnni1 (troponin 1 and Asb3 (ankyrin repeat and SOCS box-containing protein 3. Quantitative RT-PCR confirmed the direction of an increased expression in C57BL/6J genotype over the DBA/2J genotype for both genes, a difference that translated to a 2-fold difference in Asb3 protein. Although Tnni1 protein differences could not be confirmed, a 273 bp indel polymorphism was discovered 1 Kb upstream of the transcription start site. Conclusion Delivery of well supported candidate genes following a single quantitative trait locus mapping experiment is difficult. However, by combining available gene expression data with QTL mapping, we illustrated a five-filter protocol that nominated Asb3 and

  20. Genetic structure analysis of a highly inbred captive population of the African antelope Addax nasomaculatus. Conservation and management implications.

    Science.gov (United States)

    Armstrong, E; Leizagoyen, C; Martínez, A M; González, S; Delgado, J V; Postiglioni, A

    2011-01-01

    The African antelope Addax nasomaculatus is a rare mammal at high risk of extinction, with no more than 300 individuals in the wild and 1,700 captive animals distributed in zoos around the world. In this work, we combine genetic data and genealogical information to assess the structure and genetic diversity of a captive population located at Parque Lecocq Zoo (N=27), originated from only two founders. We amplified 39 microsatellites previously described in other Artiodactyls but new to this species. Seventeen markers were polymorphic, with 2-4 alleles per locus (mean=2.71). Mean expected heterozygosity (He) per locus was between 0.050 (marker ETH3) and 0.650 (marker D5S2), with a global He of 0.43. The mean inbreeding coefficient of the population computed from pedigree records of all registered individuals (N=53) was 0.222. The mean coancestry of the population was 0.298 and F(IS) index was -0.108. These results reflect the importance of an adequate breeding management on a severely bottlenecked captive population, which would benefit by the incorporation of unrelated individuals. Thanks to the successful amplification of a large number of microsatellites commonly used in domestic bovids, this study will provide useful information for the management of this population and serve as future reference for similar studies in other captive populations of this species. © 2010 Wiley-Liss, Inc.

  1. SCREENING FOR MOISTURE DEFICIT TOLERANCE IN FOUR MAIZE (Zea mays L. POPULATIONS DERIVED FROM DROUGHT TOLERANT INBRED X ADAPTED CULTIVAR CROSSES.

    Directory of Open Access Journals (Sweden)

    Gbadebo Lawrence Olaoye

    2009-02-01

    Full Text Available Efficiency of soil water utilization under moisture deficit condition can help reduce the adverse effects of drought stress in crops. Growth, physiological responses and grain yield loss due to moisture deficits around flowering, were investigated in maize populations derived by reciprocal crosses between two adapted maize cultivars (DMR-LSR-Y and AFO and two drought tolerant (DT inbred lines (DT-S3-Y and DT-S3-W under glass house conditions. The crosses and their parents and crosses were subjected to irrigation treatments equivalent to 25, 50, 75 and 100% field capacity (FC as well as water withdrawal for two weeks at vegetative, pre and post-anthesis stages respectively.  Reduction in biomass yield (BMY under low moisture regimes were within the range of 75 to 61% of BMY obtained under favourable irrigation treatments while Pre and post- anthesis moisture deficits also significantly reduced grain yield by 49 and 66% of well-watered condition. Reciprocal crosses between AFO and DT-S3-Y consistently gave highest BMY under irrigation treatment equivalent to 75% FC and above with % gains ranging from 3.05 to 44.2 respectively. All crosses except two of them (DT-S3-Y x AFO and AFO x DT-S3-W evidenced superiority for BMY and water use efficiency (WUE over their respective better parents, under low moisture conditions. Heterotic response for grain yield differed among crosses depending on soil moisture condition. There was no direct association between drought sensitivity index (DSI and grain yield in the populations but genotypes with short anthesis-silking-interval (ASI under moisture deficit conditions showed superiority for grain yield over those with longer ASI. The above results suggest that short ASI when combined with high grain yield under moisture deficit conditions is a better selection tool for identifying drought tolerant genotypes than DSI.

  2. ROOT TRAITS AND NODULATION OF RECOMBINANT INBRED BEAN LINES FROM A ‘JAMAPA × CALIMA’ POPULATION INOCULATED WITH TWO STRAINS OF RHIZOBIUM

    Science.gov (United States)

    Bean cultivars of Andean and Middle American origin often have contrasting above-ground traits. Less is known, however, of possible differences in root traits of beans from different gene pools. Recombinant inbred lines (RIL) derived from a cross between the Andean cultivar ‘Calima’ and the Middle A...

  3. Array-based genotyping and genetic dissimilarity analysis of a set of maize inbred lines belonging to different heterotic groups

    Directory of Open Access Journals (Sweden)

    Jambrović Antun

    2014-01-01

    Full Text Available Here we describe the results of the detailed array-based genotyping obtained by using the Illumina MaizeSNP50 BeadChip of eleven inbred lines belonging to different heterotic groups relevant for maize breeding in Southeast Europe - European Corn Belt. The objectives of this study were to assess the utility of the MaizeSNP50 BeadChip platform by determining its descriptive power and to assess genetic dissimilarity of the inbred lines. The distribution of the SNPs was found not completely uniform among chromosomes, but average call rate was very high (97.9% and number of polymorphic loci was 33200 out of 50074 SNPs with known mapping position indicating descriptive power of the MaizeSNP50 BeadChip. The dendrogram obtained from UPGMA cluster analysis as well as principal component analysis (PCA confirmed pedigree information, undoubtedly distinguishing lines according to their background in two population varieties of Reid Yellow Dent and Lancaster Sure Crop. Dissimilarity analysis showed that all of the inbred lines could be distinguished from each other. Whereas cluster analysis did not definitely differentiate Mo17 and Ohio inbred lines, PCA revealed clear genetic differences between them. The studied inbred lines were confirmed to be genetically diverse, representing a large proportion of the genetic variation occurring in two maize heterotic groups.

  4. Genetic properties of the MAGIC maize population: a new platform for high definition QTL mapping in Zea mays.

    Science.gov (United States)

    Dell'Acqua, Matteo; Gatti, Daniel M; Pea, Giorgio; Cattonaro, Federica; Coppens, Frederik; Magris, Gabriele; Hlaing, Aye L; Aung, Htay H; Nelissen, Hilde; Baute, Joke; Frascaroli, Elisabetta; Churchill, Gary A; Inzé, Dirk; Morgante, Michele; Pè, Mario Enrico

    2015-09-11

    Maize (Zea mays) is a globally produced crop with broad genetic and phenotypic variation. New tools that improve our understanding of the genetic basis of quantitative traits are needed to guide predictive crop breeding. We have produced the first balanced multi-parental population in maize, a tool that provides high diversity and dense recombination events to allow routine quantitative trait loci (QTL) mapping in maize. We produced 1,636 MAGIC maize recombinant inbred lines derived from eight genetically diverse founder lines. The characterization of 529 MAGIC maize lines shows that the population is a balanced, evenly differentiated mosaic of the eight founders, with mapping power and resolution strengthened by high minor allele frequencies and a fast decay of linkage disequilibrium. We show how MAGIC maize may find strong candidate genes by incorporating genome sequencing and transcriptomics data. We discuss three QTL for grain yield and three for flowering time, reporting candidate genes. Power simulations show that subsets of MAGIC maize might achieve high-power and high-definition QTL mapping. We demonstrate MAGIC maize's value in identifying the genetic bases of complex traits of agronomic relevance. The design of MAGIC maize allows the accumulation of sequencing and transcriptomics layers to guide the identification of candidate genes for a number of maize traits at different developmental stages. The characterization of the full MAGIC maize population will lead to higher power and definition in QTL mapping, and lay the basis for improved understanding of maize phenotypes, heterosis included. MAGIC maize is available to researchers.

  5. Selection of popcorn inbred lines based on performance and genealogy of S5 progenies and plants

    Directory of Open Access Journals (Sweden)

    José Marcelo Soriano Viana

    2009-01-01

    Full Text Available The development of hybrids is the most important objective in a corn breeding program. The objectives of thisstudy were to select and assess inbred lines, and to discuss the efficiency of four cycles of among and within inbred familyselection. Two experiments were evaluated, one with 144 S5 progenies of the popcorn population Beija-Flor and another withseven inbred lines. Based on expected gains in expansion volume, the best selective procedure was mass selection. The 14selected inbred lines should be divergent, because only two pairs were derived from the same S3 or S4 family. The analysis ofselection efficiency demonstrated that it is important to select superior plants in families with poorer performance to minimizethe loss of superior genotypes. The quality of the evaluated inbred lines was comparable to commercial populations and theyield satisfactory. The information about genealogy did not increase the inbred line selection efficiency.

  6. Genomic Dissection of Leaf Angle in Maize (Zea mays L. Using a Four-Way Cross Mapping Population.

    Directory of Open Access Journals (Sweden)

    Junqiang Ding

    Full Text Available Increasing grain yield by the selection for optimal plant architecture has been the key focus in modern maize breeding. As a result, leaf angle, an important determinant of plant architecture, has been significantly improved to adapt to the ever-increasing plant density in maize production over the past several decades. To extend our understanding on the genetic mechanisms of leaf angle in maize, we developed the first four-way cross mapping population, consisting of 277 lines derived from four maize inbred lines with varied leaf angles. The four-way cross mapping population together with the four parental lines were evaluated for leaf angle in two environments. In this study, we reported linkage maps built in the population and quantitative trait loci (QTL on leaf angle detected by inclusive composite interval mapping (ICIM. ICIM applies a two-step strategy to effectively separate the cofactor selection from the interval mapping, which controls the background additive and dominant effects at the same time. A total of 14 leaf angle QTL were identified, four of which were further validated in near-isogenic lines (NILs. Seven of the 14 leaf angle QTL were found to overlap with the published leaf angle QTL or genes, and the remaining QTL were unique to the four-way population. This study represents the first example of QTL mapping using a four-way cross population in maize, and demonstrates that the use of specially designed four-way cross is effective in uncovering the basis of complex and polygenetic trait like leaf angle in maize.

  7. Genetic analysis of japonica x indica recombinant inbred lines and ...

    African Journals Online (AJOL)

    Genetic analysis of japonica x indica recombinant inbred lines and characterization of major fragrance gene by microsatellite markers. ... At some SSR loci, new/recombinant alleles were observed, which indicate the active recombination between genomes of two rice varieties and can be used for linkage mapping once ...

  8. Genetic analysis of resistance to six virus diseases in a multiple virus-resistant maize inbred line.

    Science.gov (United States)

    Zambrano, Jose Luis; Jones, Mark W; Brenner, Eric; Francis, David M; Tomas, Adriana; Redinbaugh, Margaret G

    2014-04-01

    Novel and previously known resistance loci for six phylogenetically diverse viruses were tightly clustered on chromosomes 2, 3, 6 and 10 in the multiply virus-resistant maize inbred line, Oh1VI. Virus diseases in maize can cause severe yield reductions that threaten crop production and food supplies in some regions of the world. Genetic resistance to different viruses has been characterized in maize populations in diverse environments using different screening techniques, and resistance loci have been mapped to all maize chromosomes. The maize inbred line, Oh1VI, is resistant to at least ten viruses, including viruses in five different families. To determine the genes and inheritance mechanisms responsible for the multiple virus resistance in this line, F1 hybrids, F2 progeny and a recombinant inbred line (RIL) population derived from a cross of Oh1VI and the virus-susceptible inbred line Oh28 were evaluated. Progeny were screened for their responses to Maize dwarf mosaic virus, Sugarcane mosaic virus, Wheat streak mosaic virus, Maize chlorotic dwarf virus, Maize fine streak virus, and Maize mosaic virus. Depending on the virus, dominant, recessive, or additive gene effects were responsible for the resistance observed in F1 plants. One to three gene models explained the observed segregation of resistance in the F2 generation for all six viruses. Composite interval mapping in the RIL population identified 17 resistance QTLs associated with the six viruses. Of these, 15 were clustered in specific regions of chr. 2, 3, 6, and 10. It is unknown whether these QTL clusters contain single or multiple virus resistance genes, but the coupling phase linkage of genes conferring resistance to multiple virus diseases in this population could facilitate breeding efforts to develop multi-virus resistant crops.

  9. Assessment and genetic analysis of heavy metal content in rice grain using an Oryza sativa × O. rufipogon backcross inbred line population.

    Science.gov (United States)

    Huang, De-Run; Fan, Ye-Yang; Hu, Biao-Lin; Xiao, Ye-Qing; Chen, Da-Zhou; Zhuang, Jie-Yun

    2018-03-01

    Heavy metal accumulation in rice is a growing concern for public health. Backcross inbred lines derived from an interspecific cross of Oryza sativa × O. rufipogon were grown in two distinct ecological locations (Hangzhou and Lingshui, China). The objective of this study was to characterise the contents of heavy metal in rice grains, and to identify quantitative trait loci (QTLs) for heavy metal contents. The contents of Ni, As, Pb, Cr and Hg in milled rice showed a significant decline as compared with those in brown rice, whereas the content of Cd showed little change. The concentration of heavy metal in rice grain varied greatly between the two environments. A total of 24 QTLs responsible for heavy metal contents were detected, including two for both the brown and milled rice, 13 for brown rice only, and nine for milled rice only. All the QTLs except two had the enhancing alleles derived from O. rufipogon. Sixteen QTLs were clustered in six chromosomal regions. Environmental variation plays an important role in the heavy metal contents in rice grain. QTLs detected in this study might be useful for breeding rice varieties with low heavy metal content. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  10. Methods for association mapping using multiple population data

    DEFF Research Database (Denmark)

    Kadri, Naveen Kumar

    This thesis forcused on comparing methods for associationg genetic marker with variation in phenotypes in structured populations. It also focuses on the application of these methods in mapping/fine-mapping QTL affecting production, fertility and mastitis in five breeds of dairy cattle. The most...

  11. Identification of quantitative trait loci controlling root and shoot traits associated with drought tolerance in a lentil (Lens culinaris Medik. recombinant inbred line population

    Directory of Open Access Journals (Sweden)

    Omar Idrissi

    2016-08-01

    Full Text Available Drought is one of the major abiotic stresses limiting lentil productivity in rainfed production systems. Specific rooting patterns can be associated with drought avoidance mechanisms that can be used in lentil breeding programs. In all, 252 co-dominant and dominant markers were used for Quantitative Trait Loci (QTL analysis on 132 lentil recombinant inbred lines based on greenhouse experiments for root and shoot traits during two seasons under progressive drought-stressed conditions. Eighteen QTLs controlling a total of 14 root and shoot traits were identified. A QTL-hotspot genomic region related to a number of root and shoot characteristics associated with drought tolerance such as dry root biomass, root surface area, lateral root number, dry shoot biomass and shoot length was identified. Interestingly, a QTL related to root-shoot ratio, an important trait for drought avoidance, explaining the highest phenotypic variance of 27.6 % and 28.9 % for the two consecutive seasons, respectively, was detected. This QTL was closed to the co-dominant SNP marker TP6337 and also flanked by the two SNP TP518 and TP1280. An important QTL related to lateral root number was found close to TP3371 and flanked by TP5093 and TP6072 SNP markers. Also, a QTL associated with specific root length was identified close to TP1873 and flanked by F7XEM6b SRAP marker and TP1035 SNP marker. These two QTLs were detected in both seasons. Our results could be used for marker-assisted selection in lentil breeding programs targeting root and shoot characteristics conferring drought avoidance as an efficient alternative to slow and labour-intensive conventional breeding methods.

  12. Heterosis For Litter Traits In Native By Exotic Inbred Pig Crosses ...

    African Journals Online (AJOL)

    Inbred strains generated from native and exotic pigs were compared with their F1 and F2 backcross populations for a range of litter performance traits. Animals were intensively reared and at 81/2 months of age, the inbred genotypes from each strain were reciprocally mated to each other to generate F1 crossbred genotypes ...

  13. Ultrahigh-Density Linkage Map Construction Using Low-Coverage Whole-Genome Sequencing of a Doubled Haploid Population: Case Study of Torafugu (Takifugu rubripes).

    Science.gov (United States)

    Zhang, Xiang; Mizukoshi, Misaki; Zhang, Hong; Tan, Engkong; Igarashi, Yoji; Suzuki, Yutaka; Mitsuyama, Susumu; Kinoshita, Shigeharu; Saito, Kazuyoshi; Watabe, Shugo; Asakawa, Shuichi

    2018-02-26

    Next-generation sequencing enables genome-wide genotyping of a large population and further facilitates the construction of a genetic linkage map. Low-coverage whole-genome sequencing has been employed for genetic linkage map construction in several species. However, this strategy generally requires available high-quality reference genomes and/or designed inbred pedigree lines, which restrict the scope of application for non-model and unsequenced species. Here, using torafugu ( Takifugu rubripes ) as a test model, we propose a new strategy for ultrahigh-density genetic linkage map construction using low-coverage whole-genome sequencing of a haploid/doubled haploid (H/DH) population without above requirements. Low-coverage (≈1×) whole-genome sequencing data of 165 DH individuals were used for de novo assembly and further performed single nucleotide polymorphisms (SNPs) calling, resulting in the identification of 1,070,601 SNPs. Based on SNP genotypes and de novo assembly, genotypes were associated with short DNA segments and an ultrahigh-density linkage map was constructed containing information of 802,277 SNPs in 3090 unique positions. Comparative analyses showed near-perfect concordance between the present linkage map and the latest published torafugu genome (FUGU5). This strategy would facilitate ultrahigh-density linkage map construction in various sexually reproducing organisms for which H/DH populations can be generated.

  14. Ultrahigh-Density Linkage Map Construction Using Low-Coverage Whole-Genome Sequencing of a Doubled Haploid Population: Case Study of Torafugu (Takifugu rubripes

    Directory of Open Access Journals (Sweden)

    Xiang Zhang

    2018-02-01

    Full Text Available Next-generation sequencing enables genome-wide genotyping of a large population and further facilitates the construction of a genetic linkage map. Low-coverage whole-genome sequencing has been employed for genetic linkage map construction in several species. However, this strategy generally requires available high-quality reference genomes and/or designed inbred pedigree lines, which restrict the scope of application for non-model and unsequenced species. Here, using torafugu (Takifugu rubripes as a test model, we propose a new strategy for ultrahigh-density genetic linkage map construction using low-coverage whole-genome sequencing of a haploid/doubled haploid (H/DH population without above requirements. Low-coverage (≈1× whole-genome sequencing data of 165 DH individuals were used for de novo assembly and further performed single nucleotide polymorphisms (SNPs calling, resulting in the identification of 1,070,601 SNPs. Based on SNP genotypes and de novo assembly, genotypes were associated with short DNA segments and an ultrahigh-density linkage map was constructed containing information of 802,277 SNPs in 3090 unique positions. Comparative analyses showed near-perfect concordance between the present linkage map and the latest published torafugu genome (FUGU5. This strategy would facilitate ultrahigh-density linkage map construction in various sexually reproducing organisms for which H/DH populations can be generated.

  15. Integrating population dynamics into mapping human exposure to seismic hazard

    Directory of Open Access Journals (Sweden)

    S. Freire

    2012-11-01

    Full Text Available Disaster risk is not fully characterized without taking into account vulnerability and population exposure. Assessment of earthquake risk in urban areas would benefit from considering the variation of population distribution at more detailed spatial and temporal scales, and from a more explicit integration of this improved demographic data with existing seismic hazard maps. In the present work, "intelligent" dasymetric mapping is used to model population dynamics at high spatial resolution in order to benefit the analysis of spatio-temporal exposure to earthquake hazard in a metropolitan area. These night- and daytime-specific population densities are then classified and combined with seismic intensity levels to derive new spatially-explicit four-class-composite maps of human exposure. The presented approach enables a more thorough assessment of population exposure to earthquake hazard. Results show that there are significantly more people potentially at risk in the daytime period, demonstrating the shifting nature of population exposure in the daily cycle and the need to move beyond conventional residence-based demographic data sources to improve risk analyses. The proposed fine-scale maps of human exposure to seismic intensity are mainly aimed at benefiting visualization and communication of earthquake risk, but can be valuable in all phases of the disaster management process where knowledge of population densities is relevant for decision-making.

  16. Genotyping-by-Sequencing derived High-Density Linkage Map and its Application to QTL Mapping of Flag Leaf Traits in Bread Wheat

    Science.gov (United States)

    Hard red winter wheat parents ‘Harry’ (drought tolerant) and ‘Wesley’ (drought susceptible) was used to develop a recombinant inbred population to identify genomic regions associated with drought and adaptation. To precisely map genomic regions high-density linkage maps are a prerequisite. In this s...

  17. Effect of small mapping population sizes on reliability of quantitative ...

    African Journals Online (AJOL)

    A limitation of quantitative trait loci (QTL) mapping is that accuracy of determining QTL position and effects are largely determined by population size. Despite the importance of this concept, known as the "Beavis effect there has generally been a lack of understanding by molecular geneticists and breeders. One possible ...

  18. Development of mapping populations for genetic analysis in yams ...

    African Journals Online (AJOL)

    Progress is being made at the International Institute of Tropical Agriculture (IITA, Ibadan, Nigeria) to develop molecular tools for marker-assisted selection that would complement and expedite conventional breeding approaches for genetic improvement of yams (Dioscorea spp.). F1 full-sib mapping populations were ...

  19. Índice baseado em RFLPs para seleção de linhagens visando sintéticos de milho RFLP marker index for selection of inbred lines aimed at synthetic maize populations

    Directory of Open Access Journals (Sweden)

    Glauce Cristina Ricardo Rumin

    2001-06-01

    maize populations. It is based on field data and the RFLP genotypes of seed parents. Index usefulness was examined, considering its efficiency for generating synthetics with high QTL frequencies, in contrast with line selection based solely on topcross performance. Seed parents were genotyped for 157 RFLP marker loci with an average distance between loci of 15.30 cM. Sixty-eight S2 lines, stemming from an F2 population derived from a cross between two homozygous inbred lines, were topcrossed and evaluated in four locations in Iowa, USA, in 1996. From these 157 loci, 18 were identified as significantly associated with yield QTLs explaining 74.70 % of the genetic variance among topcross progenies. The proposed index included measures which are function of the per se line behaviour and the genetic complementarity between lines, and led to a diallel table homologue for all parental lines. These properties cannot be accomplished using only the topcross selection criterion. The index led to synthetic populations which are expected to be superior to the best synthetic population selected by topcross performance alone. However, this superiority is valid only for QTL regions covered by the markers used. This procedure allowed a useful monitoring of the genetic constitution of all possible synthetic populations.

  20. The mouse as a model for understanding chronic diseases of aging: the histopathologic basis of aging in inbred mice

    Directory of Open Access Journals (Sweden)

    David Harrison

    2011-06-01

    Full Text Available Inbred mice provide a unique tool to study aging populations because of the genetic homogeneity within an inbred strain, their short life span, and the tools for analysis which are available. A large-scale longitudinal and cross-sectional aging study was conducted on 30 inbred strains to determine, using histopathology, the type and diversity of diseases mice develop as they age. These data provide tools that when linked with modern in silico genetic mapping tools, can begin to unravel the complex genetics of many of the common chronic diseases associated with aging in humans and other mammals. In addition, novel disease models were discovered in some strains, such as rhabdomyosarcoma in old A/J mice, to diseases affecting many but not all strains including pseudoxanthoma elasticum, pulmonary adenoma, alopecia areata, and many others. This extensive data set is now available online and provides a useful tool to help better understand strain-specific background diseases that can complicate interpretation of genetically engineered mice and other manipulatable mouse studies that utilize these strains.

  1. QTL Analysis and Nested Association Mapping for Adult Plant Resistance to Powdery Mildew in Two Bread Wheat Populations

    Directory of Open Access Journals (Sweden)

    Yan Ren

    2017-07-01

    Full Text Available CIMMYT wheat (Triticum aestivum L. lines Francolin#1 and Quaiu#3 displayed effective and stable adult plant resistance (APR to Chinese Blumeria graminis f. sp. tritici isolates in the field. To elucidate their genetic basis of resistance, two recombinant inbred line (RIL populations of their crosses with Avocet, the susceptible parent, were phenotyped in Zhengzhou and Shangqiu in the 2014–2015 and 2015–2016 cropping seasons. These populations were also genotyped with SSR (simple sequence repeat markers and DArT (diversity arrays technology markers. Two common significant quantitative trait loci (QTL on wheat chromosomes 1BL and 4BL were detected in both populations by joint and individual inclusive composite interval mapping, explaining 20.3–28.7% and 9.6–15.9% of the phenotypic variance in Avocet × Francolin#1 and 4.8–11.5% and 10.8–18.9% in Avocet × Quaiu#3, respectively. Additional QTL were mapped on chromosomes 1DL and 5BL in Avocet × Francolin#1 and on 2DL and 6BS in Avocet × Quaiu#3. Among these, QPm.heau-1DL is probably a novel APR gene contributing 6.1–8.5% of total phenotypic variance. The QTL on 1BL corresponds to the pleiotropic multi-pathogen resistance gene Yr29/Lr46/Pm39, whereas the QTL on 2DL maps to a similar region where stripe rust resistance gene Yr54 is located. The QTL identified can potentially be used for the improvement of powdery mildew and rust resistance in wheat breeding.

  2. Identification of Single Nucleotide Polymorphisms and analysis of Linkage Disequilibrium in sunflower elite inbred lines using the candidate gene approach

    Directory of Open Access Journals (Sweden)

    Heinz Ruth A

    2008-01-01

    Full Text Available Abstract Background Association analysis is a powerful tool to identify gene loci that may contribute to phenotypic variation. This includes the estimation of nucleotide diversity, the assessment of linkage disequilibrium structure (LD and the evaluation of selection processes. Trait mapping by allele association requires a high-density map, which could be obtained by the addition of Single Nucleotide Polymorphisms (SNPs and short insertion and/or deletions (indels to SSR and AFLP genetic maps. Nucleotide diversity analysis of randomly selected candidate regions is a promising approach for the success of association analysis and fine mapping in the sunflower genome. Moreover, knowledge of the distance over which LD persists, in agronomically meaningful sunflower accessions, is important to establish the density of markers and the experimental design for association analysis. Results A set of 28 candidate genes related to biotic and abiotic stresses were studied in 19 sunflower inbred lines. A total of 14,348 bp of sequence alignment was analyzed per individual. In average, 1 SNP was found per 69 nucleotides and 38 indels were identified in the complete data set. The mean nucleotide polymorphism was moderate (θ = 0.0056, as expected for inbred materials. The number of haplotypes per region ranged from 1 to 9 (mean = 3.54 ± 1.88. Model-based population structure analysis allowed detection of admixed individuals within the set of accessions examined. Two putative gene pools were identified (G1 and G2, with a large proportion of the inbred lines being assigned to one of them (G1. Consistent with the absence of population sub-structuring, LD for G1 decayed more rapidly (r2 = 0.48 at 643 bp; trend line, pooled data than the LD trend line for the entire set of 19 individuals (r2 = 0.64 for the same distance. Conclusion Knowledge about the patterns of diversity and the genetic relationships between breeding materials could be an invaluable aid in crop

  3. Gains in QTL detection using an ultra-high density SNP map based on population sequencing relative to traditional RFLP/SSR markers.

    Directory of Open Access Journals (Sweden)

    Huihui Yu

    Full Text Available Huge efforts have been invested in the last two decades to dissect the genetic bases of complex traits including yields of many crop plants, through quantitative trait locus (QTL analyses. However, almost all the studies were based on linkage maps constructed using low-throughput molecular markers, e.g. restriction fragment length polymorphisms (RFLPs and simple sequence repeats (SSRs, thus are mostly of low density and not able to provide precise and complete information about the numbers and locations of the genes or QTLs controlling the traits. In this study, we constructed an ultra-high density genetic map based on high quality single nucleotide polymorphisms (SNPs from low-coverage sequences of a recombinant inbred line (RIL population of rice, generated using new sequencing technology. The quality of the map was assessed by validating the positions of several cloned genes including GS3 and GW5/qSW5, two major QTLs for grain length and grain width respectively, and OsC1, a qualitative trait locus for pigmentation. In all the cases the loci could be precisely resolved to the bins where the genes are located, indicating high quality and accuracy of the map. The SNP map was used to perform QTL analysis for yield and three yield-component traits, number of tillers per plant, number of grains per panicle and grain weight, using data from field trials conducted over years, in comparison to QTL mapping based on RFLPs/SSRs. The SNP map detected more QTLs especially for grain weight, with precise map locations, demonstrating advantages in detecting power and resolution relative to the RFLP/SSR map. Thus this study provided an example for ultra-high density map construction using sequencing technology. Moreover, the results obtained are helpful for understanding the genetic bases of the yield traits and for fine mapping and cloning of QTLs.

  4. Some AFLP amplicons are highly conserved DNA sequences mapping to the same linkage groups in two F2 populations of carrot

    Directory of Open Access Journals (Sweden)

    Santos Carlos A.F.

    2002-01-01

    Full Text Available Amplified fragment length polymorphism (AFLP is a fast and reliable tool to generate a large number of DNA markers. In two unrelated F2 populations of carrot (Daucus carota L., Brasilia x HCM and B493 x QAL (wild carrot, it was hypothesized that DNA 1 digested with the same restriction endonuclease enzymes and amplified with the same primer combination and 2 sharing the same position in polyacrylamide gels should be conserved sequences. To test this hypothesis AFLP fragments from polyacrylamide gels were eluted, reamplified, separated in agarose gels, purified, cloned and sequenced. Among thirty-one paired fragments from each F2 population, twenty-six had identity greater than 91% and five presented identity of 24% to 44%. Among the twenty-six conserved AFLPs only one mapped to different linkage groups in the two populations while four of the five less-conserved bands mapped to different linkage groups. Of eight SCAR (sequence characterized amplified regions primers tested, one conserved AFLP resulted in co-dominant markers in both populations. Screening among 14 carrot inbreds or cultivars with three AFLP-SCAR primers revealed clear and polymorphic PCR products, with similar molecular sizes on agarose gels. The development of co-dominant markers based on conserved AFLP fragments will be useful to detect seed mixtures among hybrids, to improve and to merge linkage maps and to study diversity and phylogenetic relationships.

  5. High-Resolution Maps of Mouse Reference Populations

    Czech Academy of Sciences Publication Activity Database

    Šimeček, Petr; Forejt, Jiří; Williams, R. W.; Shiroishi, T.; Takada, T.; Lu, L.; Johnson, T. E.; Bennett, B.; Deschepper, C. F.; Scott-Boyer, M.P.; de Villena, F.P.M.; Churchill, G. A.

    2017-01-01

    Roč. 7, č. 10 (2017), s. 3427-3434 ISSN 2160-1836 R&D Projects: GA ČR GA16-01969S; GA MŠk(CZ) LM2015040; GA MŠk(CZ) LQ1604 Institutional support: RVO:68378050 Keywords : chromosome substitution strains * recombinant inbred strains * mouse diversity genotyping array * gene conversions Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 2.861, year: 2016

  6. QTL mapping of slow-rusting, adult plant resistance to race Ug99 of stem rust fungus in PBW343/Muu RIL population.

    Science.gov (United States)

    Singh, Sukhwinder; Singh, Ravi P; Bhavani, Sridhar; Huerta-Espino, Julio; Eugenio, Lopez-Vera Eric

    2013-05-01

    Races of stem rust fungus pose a major threat to wheat production worldwide. We mapped adult plant resistance (APR) to Ug99 in 141 lines of a PBW343/Muu recombinant inbred lines (RILs) population by phenotyping them for three seasons at Njoro, Kenya in field trials and genotyping them with Diversity Arrays Technology (DArT) markers. Moderately susceptible parent PBW343 and APR parent Muu displayed mean stem rust severities of 66.6 and 5 %, respectively. The mean disease severity of RILs ranged from 1 to 100 %, with an average of 23.3 %. Variance components for stem rust severity were highly significant (p stem rust where Sr2 and other minor slow rusting resistance genes can confer a higher level of resistance when present together.

  7. Genetic map of AFLP markers in the rat (Rattus norvegicus) derived from the H x B/Ipcv and B x H/cub sets of recombinant inbred strains

    Czech Academy of Sciences Publication Activity Database

    Bonné, A. C. M.; den Bieman, M. G.; Gillissen, G. F.; Křen, Vladimír; Křenová, D.; Bílá, V.; Zídek, Václav; Kostka, Vlastimil; Musilová, Alena; Pravenec, Michal; Van Zutphen, B. F. M.; Van Lith, H. A.

    2003-01-01

    Roč. 41, 3-4 (2003), s. 77-89 ISSN 0006-2928 R&D Projects: GA MŠk LN00A079; GA MŠk LN00A079; GA ČR GV204/98/K015; GA ČR GA305/00/1646 Grant - others:European Commission(XE) BIO4CT960562 Institutional research plan: CEZ:AV0Z5011922 Keywords : AFLP technique * rat * recombinant inbred strains Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.569, year: 2003

  8. Estimating and mapping the population at risk of sleeping sickness.

    Directory of Open Access Journals (Sweden)

    Pere P Simarro

    Full Text Available Human African trypanosomiasis (HAT, also known as sleeping sickness, persists as a public health problem in several sub-Saharan countries. Evidence-based, spatially explicit estimates of population at risk are needed to inform planning and implementation of field interventions, monitor disease trends, raise awareness and support advocacy. Comprehensive, geo-referenced epidemiological records from HAT-affected countries were combined with human population layers to map five categories of risk, ranging from "very high" to "very low," and to estimate the corresponding at-risk population.Approximately 70 million people distributed over a surface of 1.55 million km(2 are estimated to be at different levels of risk of contracting HAT. Trypanosoma brucei gambiense accounts for 82.2% of the population at risk, the remaining 17.8% being at risk of infection from T. b. rhodesiense. Twenty-one million people live in areas classified as moderate to very high risk, where more than 1 HAT case per 10,000 inhabitants per annum is reported.Updated estimates of the population at risk of sleeping sickness were made, based on quantitative information on the reported cases and the geographic distribution of human population. Due to substantial methodological differences, it is not possible to make direct comparisons with previous figures for at-risk population. By contrast, it will be possible to explore trends in the future. The presented maps of different HAT risk levels will help to develop site-specific strategies for control and surveillance, and to monitor progress achieved by ongoing efforts aimed at the elimination of sleeping sickness.

  9. QTLs Associated with Agronomic Traits in the Cutler × AC Barrie Spring Wheat Mapping Population Using Single Nucleotide Polymorphic Markers

    Science.gov (United States)

    Perez-Lara, Enid; Semagn, Kassa; Chen, Hua; Iqbal, Muhammad; N’Diaye, Amidou; Kamran, Atif; Navabi, Alireza; Pozniak, Curtis; Spaner, Dean

    2016-01-01

    We recently reported three earliness per se quantitative trait loci (QTL) associated with flowering and maturity in a recombinant inbred lines (RILs) population derived from a cross between the spring wheat (Triticum aestivum L.) cultivars ‘Cutler’ and ‘AC Barrie’ using 488 microsatellite and diversity arrays technology (DArT) markers. Here, we present QTLs associated with flowering time, maturity, plant height, and grain yield using high density single nucleotide polymorphic (SNP) markers in the same population. A mapping population of 158 RILs and the two parents were evaluated at five environments for flowering, maturity, plant height and grain yield under field conditions, at two greenhouse environments for flowering, and genotyped with a subset of 1809 SNPs out of the 90K SNP array and 2 functional markers (Ppd-D1 and Rht-D1). Using composite interval mapping on the combined phenotype data across all environments, we identified a total of 19 QTLs associated with flowering time in greenhouse (5), and field (6) conditions, maturity (5), grain yield (2) and plant height (1). We mapped these QTLs on 8 chromosomes and they individually explained between 6.3 and 37.8% of the phenotypic variation. Four of the 19 QTLs were associated with multiple traits, including a QTL on 2D associated with flowering, maturity and grain yield; two QTLs on 4A and 7A associated with flowering and maturity, and another QTL on 4D associated with maturity and plant height. However, only the QTLs on both 2D and 4D had major effects, and they mapped adjacent to well-known photoperiod response Ppd-D1 and height reducing Rht-D1 genes, respectively. The QTL on 2D reduced flowering and maturity time up to 5 days with a yield penalty of 436 kg ha-1, while the QTL on 4D reduced plant height by 13 cm, but increased maturity by 2 days. The high density SNPs allowed us to map eight moderate effect, two major effect, and nine minor effect QTLs that were not identified in our previous study

  10. Adaptive divergence in flowering time among natural populations of Arabidopsis thaliana: Estimates of selection and QTL mapping.

    Science.gov (United States)

    Ågren, Jon; Oakley, Christopher G; Lundemo, Sverre; Schemske, Douglas W

    2017-03-01

    To identify the ecological and genetic mechanisms of local adaptation requires estimating selection on traits, identifying their genetic basis, and evaluating whether divergence in adaptive traits is due to conditional neutrality or genetic trade-offs. To this end, we conducted field experiments for three years using recombinant inbred lines (RILs) derived from two ecotypes of Arabidopsis thaliana (Italy, Sweden), and at each parental site examined selection on flowering time and mapped quantitative trait loci (QTL). There was strong selection for early flowering in Italy, but weak selection in Sweden. Eleven distinct flowering time QTL were detected, and for each the Italian genotype caused earlier flowering. Twenty-seven candidate genes were identified, two of which (FLC and VIN3) appear under major flowering time QTL in Italy. Seven of eight QTL in Italy with narrow credible intervals colocalized with previously reported fitness QTL, in comparison to three of four in Sweden. The results demonstrate that the magnitude of selection on flowering time differs strikingly between our study populations, that the genetic basis of flowering time variation is multigenic with some QTL of large effect, and suggest that divergence in flowering time between ecotypes is due mainly to conditional neutrality. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  11. Development of Public Immortal Mapping Populations, Molecular Markers and Linkage Maps for Rapid Cycling Brassica rapa and B. oleracea

    Science.gov (United States)

    In this study we describe public immortal mapping populations of self-compatible lines, molecular markers, and linkage maps for Brassica rapa and B. oleracea. We propose that these resources are valuable reference tools for the Brassica community. The B. rapa population consists of 150 recombinant...

  12. Recurrent selection in inbred popcorn families

    Directory of Open Access Journals (Sweden)

    Daros Máskio

    2004-01-01

    Full Text Available Although much appreciated in Brazil, commercial popcorn is currently cropped on a fairly small scale. A number of problems need to be solved to increase production, notably the obtaintion of seeds with good agronomic traits and good culinary characteristics. With the objective of developing superior genotypes in popcorn, a second cycle of intrapopulation recurrent selection based on inbred S1 families was carried out. From the first cycle of selection over the UNB-2U population, 222 S1 families were obtained, which were then divided into six sets and evaluated in a randomized complete block design with two replications within the sets. Experiments were carried out in two Brazilian localities. The analysis of variance revealed environmental effects for all evaluated traits, except popping and stand, showing that, for most traits, these environments affected genotype behavior in different ways. In addition, the set as source of variation was significant for most of the evaluated traits, indicating that dividing the families into sets was an efficient strategy. Genotype-by-environment interaction was detected for most traits, except popping expansion and stand. Differences among genotypes were also detected (1% F-test, making viable the proposition of using the genetic variability in the popcorn population as a basis for future recurrent selection cycles. Superior families were selected using the Smith and Hazel classic index, with predicted genetic gains of 17.8% for popping expansion and 26.95% for yield.

  13. Quantitative trait locus (QTL) mapping for 100-kernel weight of maize

    African Journals Online (AJOL)

    Zea mays L.), related to yield. To realize its genetic basis, in this study, a recombinant inbred line (RIL) population derived from the cross between Mo17 and Huangzao4 was used for quantitative trait locus (QTL) mapping for KW under high and ...

  14. Mapping quantitative trait loci for binary trait in the F2:3 design

    Indian Academy of Sciences (India)

    cross populations derived from the cross between two inbred lines. Typically, QTL mapping statistics assumes that each. F2 individual is genotyped for the markers and phenotyped for the trait. However, the power in the detection of QTL for a trait with low heritability is relatively low. To increase the power, an F2:3 design, ...

  15. Rapid creation of Arabidopsis doubled haploid lines for quantitative trait locus mapping

    OpenAIRE

    Seymour, Danelle K.; Filiault, Daniele L.; Henry, Isabelle M.; Monson-Miller, Jennifer; Ravi, Maruthachalam; Pang, Andy; Comai, Luca; Chan, Simon W. L.; Maloof, Julin N.

    2012-01-01

    Quantitative trait loci (QTL) mapping is a powerful tool for investigating the genetic basis of natural variation. QTL can be mapped using a number of different population designs, but recombinant inbred lines (RILs) are among the most effective. Unfortunately, homozygous RIL populations are time consuming to construct, typically requiring at least six generations of selfing starting from a heterozygous F1. Haploid plants produced from an F1 combine the two parental genomes and have only one ...

  16. Genetic analysis in maize foundation parents with mapping population and testcross population: Ye478 carried more favorable alleles and using QTL information could improve foundation parents

    Directory of Open Access Journals (Sweden)

    Yinghong Liu

    2016-09-01

    Full Text Available The development of maize foundation parents is an important part of genetics and breeding research, and applying new genetic information to produce foundation parents has been challenging. In this study, we focused on quantitative trait loci (QTLs and general combining ability (GCA of Ye478, a widely used foundation parent in China. We developed three sets of populations for QTL mapping and to analyze the GCA for some agronomic traits. The assessment of 15 traits resulted in the detection of 251 QTLs in six tested environments, with 119 QTLs identified through a joint analysis across all environments. Further analyses revealed that most favorable alleles for plant type-related traits were from Ye478, and more than half of the favorable alleles for yield-related traits were from R08, another foundation parent used in southwestern China, suggesting that different types of foundation parents carried different favorable alleles. We observed that the GCA for most traits (e.g., plant height and 100-kernel weight was maintained in the inbred lines descended from the foundation parents. Additionally, the continuous improvement in the GCA of the descendants of the foundation parents was consistent with the main trend in maize breeding programs. We identified three significant genomic regions that were highly conserved in three Ye478 descendants, including the stable QTL for plant height. The GCA for the traits in the F7 generation revealed that the QTLs for the given traits per se were affected by additive effects in the same way in different populations.

  17. Comparison of association mapping methods in a complex pedigreed population

    DEFF Research Database (Denmark)

    Sahana, Goutam; Guldbrandtsen, Bernt; Janss, Luc

    2010-01-01

    Association mapping methods were compared using a simulation with a complex pedigree structure. The pedigree was simulated while keeping the present Danish Holstein population pedigree in view. A total of 15 quantitative trait loci (QTL) with varying effect sizes (10%, 5% and 2% of total genetic...... variance) were simulated. We compared the single-marker test, haplotype-based analysis, mixed model approach, and Bayesian analysis. The methods were compared for power, precision of location estimates, and type I error rates. Results found the best performance in a Bayesian method that included genetic...... background effects and simultaneously fitted all single-nucleotide polymorphisms (SNPs) with a variable selection method. A mixed model analysis that fitted genetic background effects and tested one SNP at a time performed nearly as well as the Bayesian method. For the Bayesian method, it proved necessary...

  18. Combined linkage and association mapping of flowering time in Sunflower (Helianthus annuus L.).

    Science.gov (United States)

    Cadic, Elena; Coque, Marie; Vear, Felicity; Grezes-Besset, Bruno; Pauquet, Jerôme; Piquemal, Joël; Lippi, Yannick; Blanchard, Philippe; Romestant, Michel; Pouilly, Nicolas; Rengel, David; Gouzy, Jerôme; Langlade, Nicolas; Mangin, Brigitte; Vincourt, Patrick

    2013-05-01

    Association mapping and linkage mapping were used to identify quantitative trait loci (QTL) and/or causative mutations involved in the control of flowering time in cultivated sunflower Helianthus annuus. A panel of 384 inbred lines was phenotyped through testcrosses with two tester inbred lines across 15 location × year combinations. A recombinant inbred line (RIL) population comprising 273 lines was phenotyped both per se and through testcrosses with one or two testers in 16 location × year combinations. In the association mapping approach, kinship estimation using 5,923 single nucleotide polymorphisms was found to be the best covariate to correct for effects of panel structure. Linkage disequilibrium decay ranged from 0.08 to 0.26 cM for a threshold of 0.20, after correcting for structure effects, depending on the linkage group (LG) and the ancestry of inbred lines. A possible hitchhiking effect is hypothesized for LG10 and LG08. A total of 11 regions across 10 LGs were found to be associated with flowering time, and QTLs were mapped on 11 LGs in the RIL population. Whereas eight regions were demonstrated to be common between the two approaches, the linkage disequilibrium approach did not detect a documented QTL that was confirmed using the linkage mapping approach.

  19. QTL map meets population genomics: an application to rice.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Fawcett

    Full Text Available Genes involved in the transition from wild to cultivated crop species should be of great agronomic importance. Population genomic approaches utilizing genome resequencing data have been recently applied for this purpose, although it only reports a large list of candidate genes with no biological information. Here, by resequencing more than 30 genomes altogether of wild rice Oryza rufipogon and cultivated rice O. sativa, we identified a number of regions with clear footprints of selection during the domestication process. We then focused on identifying candidate domestication genes in these regions by utilizing the wealth of QTL information in rice. We were able to identify a number of interesting candidates such as transcription factors that should control key domestication traits such as shattering, awn length, and seed dormancy. Other candidates include those that might have been related to the improvement of grain quality and those that might have been involved in the local adaptation to dry conditions and colder environments. Our study shows that population genomic approaches and QTL mapping information can be used together to identify genes that might be of agronomic importance.

  20. Crop characteristics and weed Interactions of diverse Rrecurrent Inbred Lines (RILs) from a weed-suppressive x non-suppressive rice mapping population

    Science.gov (United States)

    ndica rice genotypes with enhanced weed suppression traits have been previously identified as potentially useful in supplementing weed control efforts in drill-seeded systems in the southern USA. A particularly weed-suppressive indica genotype (PI 312777) that was also high tillering and high yield...

  1. Morphological variation in maize inbred lines

    Directory of Open Access Journals (Sweden)

    Jiban Shrestha

    2014-05-01

    Full Text Available In order to identify morphological variation in maize inbred lines, one hundred five inbred lines were planted under randomized complete block design with two replications at research field of National Maize Research Program, Rampur, Chitwan, Nepal during summer season (March to June, 2010. Descriptive statistics and cluster analysis were done. The results revealed a wide range of morphological variation among the tested inbred lines. The inbred lines grouped in cluster 4 namely PUTU-13, L-9, RL-105, RL-197, RL-103, RML-9, RML-41, RL-165, RL-36, RL-76, RL-125, RL-30-3, L-6, RL-107, RL-174, RL-41, L-13, RML-76 and L-5 had 0.833 days anthesis-silking interval and earlier in flowering (tasseling in 54.50 days and silking in 55.33 days. Moreover they consisted of 1.16 plant aspect, 1.25 ear aspect, 33.08 cm tassel length and 13.5 tassel branch number. Among tested lines, the above inbred lines had better morphological traits, so it was concluded that they were good candidates for development of hybrids and synthetic varieties. DOI: http://dx.doi.org/10.3126/ije.v3i2.10521 International Journal of the Environment Vol.3(2 2014: 98-107

  2. Procedimento para escolha de populações de milho promissoras para extração de linhagens Procedure to select superior maize populations for inbred line extraction

    Directory of Open Access Journals (Sweden)

    MAX WENDEL PAULA LIMA

    2000-01-01

    Full Text Available O sucesso de um programa de melhoramento de milho visando à obtenção de híbridos está intimamente ligado à identificação da população mais promissora para a extração de linhagens. O presente trabalho objetivou identificar procedimentos para a escolha dessas populações. Para isso, foram obtidas populações segregantes S0, S1 e 196 famílias S0:1 de cada um dos quatro materiais comerciais avaliados: híbridos simples (C 333B e Z 8392, duplo (AG 1051 e variedade (BR-105. Os experimentos foram conduzidos na safra agrícola 98/99 em duas localidades na região sul do Estado de Minas Gerais: Lavras e Ijaci. Na avaliação das 196 famílias S0:1 de cada população foi empregado o delineamento látice simples 14 x 14. Adicionalmente foi instalado um experimento em blocos casualizados, com 4 repetições, para avaliação simultânea das gerações F1, S0 e S1 A partir dos dados de produtividade de espigas despalhadas (kg por parcela das gerações F1, S0 e S1, foram obtidas as estimativas da contribuição dos locos em homozigose (m + a e em heterozigose (d. Foram também foram estimados os parâmetros genéticos e fenotípicos com os experimentos das famílias S0:1. Constatou-se que houve boa associação (r = 0,81 entre a estimativa de (m + a e a média das famílias S0:1 e que população com maior potencial para a extração de linhagens, maior (m + a, foi a AG 1051. A correlação entre as estimativas de (d e h² foi baixa, indicando que a estimativa da contribuição dos locos em heterozigose não foi bom indicador da variabilidade potencial da população.The identification of the population with greatest potential for inbred line extraction is directly linked to the success of a maize hybrid breeding program. This study was carried out to identify procedures for selecting these populations. Segregant S0, S1 populations and 196 S0:1 families were obtained from each of four commercial cultivars assessed: single hybrids (C 333B and

  3. Mapping young stellar populations toward Orion with Gaia DR1

    Science.gov (United States)

    Zari, E.; Brown, A. G. A.; de Bruijne, J.; Manara, C. F.; de Zeeuw, P. T.

    2017-12-01

    In this work we use the first data release of the Gaia mission to explore the three-dimensional arrangement and age ordering of the many stellar groups toward the Orion OB association, aiming at a new classification and characterization of the stellar population not embedded in the Orion A and B molecular clouds. We make use of the parallaxes and proper motions provided in the Tycho Gaia Astrometric Solution (TGAS) subset of the Gaia Data Release 1 (DR1) catalog and of the combination of Gaia DR1 and 2MASS photometry. In TGAS, we find evidence for the presence of a young population at a parallax ϖ 2.65 mas, which is loosely distributed around the following known clusters: 25 Ori, ɛ Ori, and σ Ori, and NGC 1980 (ι Ori) and the Orion Nebula Cluster (ONC). The low mass counterpart of this population is visible in the color magnitude diagrams constructed by combining Gaia DR1 G-band photometry and 2MASS. We study the density distribution of the young sources in the sky using a kernel density estimation (KDE). We find the same groups as in TGAS and also some other density enhancements that might be related to the recently discovered Orion X group, Orion dust ring, and λ Ori complex. The maps also suggest that the 25 Ori group presents a northern elongation. We estimated the ages of this population using a Bayesian isochronal fitting procedure assuming a unique parallax value for all the sources, and we inferred the presence of an age gradient going from 25 Ori (13-15 Myr) to the ONC (1-2 Myr). We confirmed this age ordering by repeating the Bayesian fit using the Pan-STARRS1 data. Intriguingly, the estimated ages toward the NGC 1980 cluster span a broad range of values. This can either be due to the presence of two populations coming from two different episodes of star formation or to a large spread along the line of sight of the same population. Some confusion might arise from the presence of unresolved binaries, which are not modeled in the fit, and usually mimic

  4. Combing Ability Analysis ofamong Early Generation Maize Inbred ...

    African Journals Online (AJOL)

    dagne.cimdom

    estimate combining ability effects of locally developed and introduced early generation maize inbred lines for grain yield, yield .... mass selection followed by self-pollination for generating inbred lines. The inbred lines ... for the experiment was an alpha (0, 1) lattice (Patterson and Williams, 1996) with two replications at each ...

  5. High Resolution Population Maps for Low Income Nations: Combining Land Cover and Census in East Africa

    Science.gov (United States)

    Tatem, Andrew J.; Noor, Abdisalan M.; von Hagen, Craig; Di Gregorio, Antonio; Hay, Simon I.

    2007-01-01

    Background Between 2005 and 2050, the human population is forecast to grow by 2.7 billion, with the vast majority of this growth occurring in low income countries. This growth is likely to have significant social, economic and environmental impacts, and make the achievement of international development goals more difficult. The measurement, monitoring and potential mitigation of these impacts require high resolution, contemporary data on human population distributions. In low income countries, however, where the changes will be concentrated, the least information on the distribution of population exists. In this paper we investigate whether satellite imagery in combination with land cover information and census data can be used to create inexpensive, high resolution and easily-updatable settlement and population distribution maps over large areas. Methodology/Principal Findings We examine various approaches for the production of maps of the East African region (Kenya, Uganda, Burundi, Rwanda and Tanzania) and where fine resolution census data exists, test the accuracies of map production approaches and existing population distribution products. The results show that combining high resolution census, settlement and land cover information is important in producing accurate population distribution maps. Conclusions We find that this semi-automated population distribution mapping at unprecedented spatial resolution produces more accurate results than existing products and can be undertaken for as little as $0.01 per km2. The resulting population maps are a product of the Malaria Atlas Project (MAP: http://www.map.ox.ac.uk) and are freely available. PMID:18074022

  6. High resolution population maps for low income nations: combining land cover and census in East Africa.

    Directory of Open Access Journals (Sweden)

    Andrew J Tatem

    2007-12-01

    Full Text Available Between 2005 and 2050, the human population is forecast to grow by 2.7 billion, with the vast majority of this growth occurring in low income countries. This growth is likely to have significant social, economic and environmental impacts, and make the achievement of international development goals more difficult. The measurement, monitoring and potential mitigation of these impacts require high resolution, contemporary data on human population distributions. In low income countries, however, where the changes will be concentrated, the least information on the distribution of population exists. In this paper we investigate whether satellite imagery in combination with land cover information and census data can be used to create inexpensive, high resolution and easily-updatable settlement and population distribution maps over large areas.We examine various approaches for the production of maps of the East African region (Kenya, Uganda, Burundi, Rwanda and Tanzania and where fine resolution census data exists, test the accuracies of map production approaches and existing population distribution products. The results show that combining high resolution census, settlement and land cover information is important in producing accurate population distribution maps.We find that this semi-automated population distribution mapping at unprecedented spatial resolution produces more accurate results than existing products and can be undertaken for as little as $0.01 per km(2. The resulting population maps are a product of the Malaria Atlas Project (MAP: http://www.map.ox.ac.uk and are freely available.

  7. Fine-scale map of encyclopedia of DNA elements regions in the Korean population.

    Science.gov (United States)

    Yoo, Yeon-Kyeong; Ke, Xiayi; Hong, Sungwoo; Jang, Hye-Yoon; Park, Kyunghee; Kim, Sook; Ahn, TaeJin; Lee, Yeun-Du; Song, Okryeol; Rho, Na-Young; Lee, Moon Sue; Lee, Yeon-Su; Kim, Jaeheup; Kim, Young J; Yang, Jun-Mo; Song, Kyuyoung; Kimm, Kyuchan; Weir, Bruce; Cardon, Lon R; Lee, Jong-Eun; Hwang, Jung-Joo

    2006-09-01

    The International HapMap Project aims to generate detailed human genome variation maps by densely genotyping single-nucleotide polymorphisms (SNPs) in CEPH, Chinese, Japanese, and Yoruba samples. This will undoubtedly become an important facility for genetic studies of diseases and complex traits in the four populations. To address how the genetic information contained in such variation maps is transferable to other populations, the Korean government, industries, and academics have launched the Korean HapMap project to genotype high-density Encyclopedia of DNA Elements (ENCODE) regions in 90 Korean individuals. Here we show that the LD pattern, block structure, haplotype diversity, and recombination rate are highly concordant between Korean and the two HapMap Asian samples, particularly Japanese. The availability of information from both Chinese and Japanese samples helps to predict more accurately the possible performance of HapMap markers in Korean disease-gene studies. Tagging SNPs selected from the two HapMap Asian maps, especially the Japanese map, were shown to be very effective for Korean samples. These results demonstrate that the HapMap variation maps are robust in related populations and will serve as an important resource for the studies of the Korean population in particular.

  8. Genetic analysis in the Collaborative Cross breeding population

    Energy Technology Data Exchange (ETDEWEB)

    Philip, Vivek [University of Tennessee, Knoxville (UTK); Sokoloff, Greta [ORNL; Ackert-Bicknell, Cheryl [Jackson Laboratory, The, Bar Harbor, ME; Striz, Martin [University of Kentucky, Lexington; Branstetter, Lisa R [ORNL; Beckmann, Melissa [ORNL; Spence, Jason S [ORNL; Jackson, Barbara L [ORNL; Galloway, Leslie D [ORNL; Barker, Gene [ORNL; Wymore, Ann M [Oak Ridge National Laboratory (ORNL); Hunsicker, Patricia R [ORNL; Durtschi, David W [University of Kentucky, Lexington; Shaw, Ginger S [University of Kentucky, Lexington; Shinpock, Sarah G [ORNL; Manly, Kenneth F [University of Kentucky, Lexington; Miller, Darla R [ORNL; Donahue, Kevin [University at Buffalo, NY; Culiat, Cymbeline T [ORNL; Churchill, Gary A [Jackson Laboratory, The, Bar Harbor, ME; Lariviere, William R [University of Pittsburgh; Palmer, Abraham [University of Chicago; O' Hara, Bruce [University of Kentucky; Voy, Brynn H [ORNL; Chesler, Elissa J [ORNL

    2011-01-01

    Genetic reference populations in model organisms are critical resources for systems genetic analysis of disease related phenotypes. The breeding history of these inbred panels may influence detectable allelic and phenotypic diversity. The existing panel of common inbred strains reflects historical selection biases, and existing recombinant inbred panels have low allelic diversity. All such populations may be subject to consequences of inbreeding depression. The Collaborative Cross (CC) is a mouse reference population with high allelic diversity that is being constructed using a randomized breeding design that systematically outcrosses eight founder strains, followed by inbreeding to obtain new recombinant inbred strains. Five of the eight founders are common laboratory strains, and three are wild-derived. Since its inception, the partially inbred CC has been characterized for physiological, morphological, and behavioral traits. The construction of this population provided a unique opportunity to observe phenotypic variation as new allelic combinations arose through intercrossing and inbreeding to create new stable genetic combinations. Processes including inbreeding depression and its impact on allelic and phenotypic diversity were assessed. Phenotypic variation in the CC breeding population exceeds that of existing mouse genetic reference populations due to both high founder genetic diversity and novel epistatic combinations. However, some focal evidence of allele purging was detected including a suggestive QTL for litter size in a location of changing allele frequency. Despite these inescapable pressures, high diversity and precision for genetic mapping remain. These results demonstrate the potential of the CC population once completed and highlight implications for development of related populations. Supplementary material consists of Supplementary Table 1 Phenotypic means, variances, ranges and heritabilities for all traits and generations, Supplementary Table

  9. Mapping of stripe rust resistance QTL in Cappelle-Desprez × PBW343 RIL population effective in northern wheat belt of India.

    Science.gov (United States)

    Pawar, Sushma Kumari; Sharma, Davinder; Duhan, Joginder Singh; Saharan, Mahender Singh; Tiwari, Ratan; Sharma, Indu

    2016-06-01

    Stripe rust caused by Puccinia striiformis f. sp. tritici is most important and devastating disease of wheat worldwide, which affects the grain yields, quality and nutrition. To elucidate, the genetic basis of resistance, a mapping population of recombinant inbred lines was developed from a cross between resistant Cappelle-Desprez and susceptible cultivar PBW343 using single-seed descent. Variety PBW343 had been one of the most popular cultivars of North Western Plains Zone, for more than a decade, before succumbing to the stripe rust. Cappelle-Desprez, a source of durable adult plant resistance, has maintained its resistance against stripe rust for a long time in Europe. Map construction and QTL analysis were completed with 1012 polymorphic (DArT and SSR) markers. Screenings for stripe rust disease were carried out in field condition for two consecutive crop seasons (2012-2013 and 2013-2014). Susceptible parent (PBW343) achieved a significant level of disease i.e., 100 % in both the years. In present investigations, resistance in Cappelle-Desprez was found stable and response to the rust ranged from 0 to 1.5 % over the years. The estimated broad-sense heritability (h 2 ) of stripe rust rAUDPC in the mapping population was 0.82. The relative area under the disease progress curve data showed continuous distributions, indicating that trait was controlled multigenically. Genomic region identified on chromosome 2D, was located within the short arm, with flanking markers (Xgwm484-Xcfd73), explained phenotypic variation (PVE) ranged from 13.9 to 31.8 %. The genomic region identified on chromosome 5B was found with the effect of maximum contribution with flanking DArT markers (1376633|F|0-1207571|F|0), PVE ranged from 24 to 27.0 %. This can, therefore, be utilized for marker assisted selection in developing much needed stripe rust resistant lines for the northern wheat belt of India.

  10. Mapping copy number variation by population-scale genome sequencing

    DEFF Research Database (Denmark)

    Mills, Ryan E.; Walter, Klaudia; Stewart, Chip

    2011-01-01

    , copy number variants) based on whole genome DNA sequencing data from 185 human genomes, integrating evidence from complementary SV discovery approaches with extensive experimental validations. Our map encompassed 22,025 deletions and 6,000 additional SVs, including insertions and tandem duplications....... Most SVs (53%) were mapped to nucleotide resolution, which facilitated analysing their origin and functional impact. We examined numerous whole and partial gene deletions with a genotyping approach and observed a depletion of gene disruptions amongst high frequency deletions. Furthermore, we observed...... differences in the size spectra of SVs originating from distinct formation mechanisms, and constructed a map of SV hotspots formed by common mechanisms. Our analytical framework and SV map serves as a resource for sequencing-based association studies....

  11. Complex genetic architecture of cardiac disease in a wild type inbred strain of Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Zhi Zhang

    Full Text Available Natural populations of the fruit fly, Drosophila melanogaster, segregate genetic variation that leads to cardiac disease phenotypes. One nearly isogenic line from a North Carolina peach orchard, WE70, is shown to harbor two genetically distinct heart phenotypes: elevated incidence of arrhythmias, and a dramatically constricted heart diameter in both diastole and systole, with resemblance to restrictive cardiomyopathy in humans. Assuming the source to be rare variants of large effect, we performed Bulked Segregant Analysis using genomic DNA hybridization to Affymetrix chips to detect single feature polymorphisms, but found that the mutant phenotypes are more likely to have a polygenic basis. Further mapping efforts revealed a complex architecture wherein the constricted cardiomyopathy phenotype was observed in individual whole chromosome substitution lines, implying that variants on both major autosomes are sufficient to produce the phenotype. A panel of 170 Recombinant Inbred Lines (RIL was generated, and a small subset of mutant lines selected, but these each complemented both whole chromosome substitutions, implying a non-additive (epistatic contribution to the "disease" phenotype. Low coverage whole genome sequencing was also used to attempt to map chromosomal regions contributing to both the cardiomyopathy and arrhythmia, but a polygenic architecture had to be again inferred to be most likely. These results show that an apparently simple rare phenotype can have a complex genetic basis that would be refractory to mapping by deep sequencing in pedigrees. We present this as a cautionary tale regarding assumptions related to attempts to map new disease mutations on the assumption that probands carry a single causal mutation.

  12. Genetic mapping of quantitative trait loci (QTLs) with effects on ...

    African Journals Online (AJOL)

    Genetic mapping of quantitative trait loci (QTLs) with effects on resistance to flower bud thrips ( Megalurothrips sjostedti ) identified in recombinant inbred lines of cowpea ( Vigna unguiculata (L.) Walp)

  13. The power of QTL mapping with RILs.

    Directory of Open Access Journals (Sweden)

    Shohei Takuno

    Full Text Available QTL (quantitative trait loci mapping is commonly used to identify genetic regions responsible to important phenotype variation. A common strategy of QTL mapping is to use recombinant inbred lines (RILs, which are usually established by several generations of inbreeding of an F1 population (usually up to F6 or F7 populations. As this inbreeding process involves a large amount of labor, we are particularly interested in the effect of the number of inbreeding generations on the power of QTL mapping; a part of the labor could be saved if a smaller number of inbreeding provides sufficient power. By using simulations, we investigated the performance of QTL mapping with recombinant inbred lines (RILs. As expected, we found that the power of F4 population could be almost comparable to that of F6 and F7 populations. A potential problem in using F4 population is that a large proportion of RILs are heterozygotes. We here introduced a new method to partly relax this problem. The performance of this method was verified by simulations with a wide range of parameters including the size of the segregation population, recombination rate, genome size and the density of markers. We found our method works better than the commonly used standard method especially when there are a number of heterozygous markers. Our results imply that in most cases, QTL mapping does not necessarily require RILs at F6 or F7 generations; rather, F4 (or even F3 populations would be almost as useful as F6 or F7 populations. Because the cost to establish a number of RILs for many generations is enormous, this finding will cause a reduction in the cost of QTL mapping, thereby accelerating gene mapping in many species.

  14. Molecular characterization of diverse CIMMYT maize inbred lines from eastern and southern Africa using single nucleotide polymorphic markers.

    Science.gov (United States)

    Semagn, Kassa; Magorokosho, Cosmos; Vivek, Bindiganavile S; Makumbi, Dan; Beyene, Yoseph; Mugo, Stephen; Prasanna, B M; Warburton, Marilyn L

    2012-03-25

    Knowledge of germplasm diversity and relationships among elite breeding materials is fundamentally important in crop improvement. We genotyped 450 maize inbred lines developed and/or widely used by CIMMYT breeding programs in both Kenya and Zimbabwe using 1065 SNP markers to (i) investigate population structure and patterns of relationship of the germplasm for better exploitation in breeding programs; (ii) assess the usefulness of SNPs for identifying heterotic groups commonly used by CIMMYT breeding programs; and (iii) identify a subset of highly informative SNP markers for routine and low cost genotyping of CIMMYT germplasm in the region using uniplex assays. Genetic distance for about 94% of the pairs of lines fell between 0.300 and 0.400. Eighty four percent of the pairs of lines also showed relative kinship values ≤ 0.500. Model-based population structure analysis, principal component analysis, neighbor-joining cluster analysis and discriminant analysis revealed the presence of 3 major groups and generally agree with pedigree information. The SNP markers did not show clear separation of heterotic groups A and B that were established based on combining ability tests through diallel and line x tester analyses. Our results demonstrated large differences among the SNP markers in terms of reproducibility, ease of scoring, polymorphism, minor allele frequency and polymorphic information content. About 40% of the SNPs in the multiplexed chip-based GoldenGate assays were found to be uninformative in this study and we recommend 644 of the 1065 for low to medium density genotyping in tropical maize germplasm using uniplex assays. There were high genetic distance and low kinship coefficients among most pairs of lines, clearly indicating the uniqueness of the majority of the inbred lines in these maize breeding programs. The results from this study will be useful to breeders in selecting best parental combinations for new breeding crosses, mapping population development

  15. Molecular characterization of diverse CIMMYT maize inbred lines from eastern and southern Africa using single nucleotide polymorphic markers

    Directory of Open Access Journals (Sweden)

    Semagn Kassa

    2012-03-01

    Full Text Available Abstract Background Knowledge of germplasm diversity and relationships among elite breeding materials is fundamentally important in crop improvement. We genotyped 450 maize inbred lines developed and/or widely used by CIMMYT breeding programs in both Kenya and Zimbabwe using 1065 SNP markers to (i investigate population structure and patterns of relationship of the germplasm for better exploitation in breeding programs; (ii assess the usefulness of SNPs for identifying heterotic groups commonly used by CIMMYT breeding programs; and (iii identify a subset of highly informative SNP markers for routine and low cost genotyping of CIMMYT germplasm in the region using uniplex assays. Results Genetic distance for about 94% of the pairs of lines fell between 0.300 and 0.400. Eighty four percent of the pairs of lines also showed relative kinship values ≤ 0.500. Model-based population structure analysis, principal component analysis, neighbor-joining cluster analysis and discriminant analysis revealed the presence of 3 major groups and generally agree with pedigree information. The SNP markers did not show clear separation of heterotic groups A and B that were established based on combining ability tests through diallel and line x tester analyses. Our results demonstrated large differences among the SNP markers in terms of reproducibility, ease of scoring, polymorphism, minor allele frequency and polymorphic information content. About 40% of the SNPs in the multiplexed chip-based GoldenGate assays were found to be uninformative in this study and we recommend 644 of the 1065 for low to medium density genotyping in tropical maize germplasm using uniplex assays. Conclusions There were high genetic distance and low kinship coefficients among most pairs of lines, clearly indicating the uniqueness of the majority of the inbred lines in these maize breeding programs. The results from this study will be useful to breeders in selecting best parental combinations

  16. Something old and something new: wedding recombinant inbred lines with traditional line cross analysis increases power to describe gene interactions.

    Science.gov (United States)

    Elnaccash, Tarek W; Tonsor, Stephen J

    2010-04-16

    In this paper we present a novel approach to quantifying genetic architecture that combines recombinant inbred lines (RIL) with line cross analysis (LCA). LCA is a method of quantifying directional genetic effects (i.e. summed effects of all loci) that differentiate two parental lines. Directional genetic effects are thought to be critical components of genetic architecture for the long term response to selection and as a cause of inbreeding depression. LCA typically begins with two inbred parental lines that are crossed to produce several generations such as F1, F2, and backcrosses to each parent. When a RIL population (founded from the same P1 and P2 as was used to found the line cross population) is added to the LCA, the sampling variance of several nonadditive genetic effect estimates is greatly reduced. Specifically, estimates of directional dominance, additive x additive, and dominance x dominance epistatic effects are reduced by 92%, 94%, and 56% respectively. The RIL population can be simultaneously used for QTL identification, thus uncovering the effects of specific loci or genomic regions as elements of genetic architecture. LCA and QTL mapping with RIL provide two qualitatively different measures of genetic architecture with the potential to overcome weaknesses of each approach alone. This approach provides cross-validation of the estimates of additive and additive x additive effects, much smaller confidence intervals on dominance, additive x additive and dominance x dominance estimates, qualitatively different measures of genetic architecture, and the potential when used together to balance the weaknesses of LCA or RIL QTL analyses when used alone.

  17. Population structure and association mapping studies for important ...

    Indian Academy of Sciences (India)

    2014-12-18

    Dec 18, 2014 ... It has been identified as a tool to resolve com- plex trait variations down to the sequence level ( ..... Association mapping is a powerful tool to establish the marker-trait associations. Its applicability as well .... MLM method was proven to be useful in controlling false associations. This study, thus, reaffirms the ...

  18. Population weighted raster maps can communicate findings of social audits: examples from three continents

    Directory of Open Access Journals (Sweden)

    Mitchell Steven

    2011-12-01

    Full Text Available Abstract Background Maps can portray trends, patterns, and spatial differences that might be overlooked in tabular data and are now widely used in health research. Little has been reported about the process of using maps to communicate epidemiological findings. Method Population weighted raster maps show colour changes over the study area. Similar to the rasters of barometric pressure in a weather map, data are the health occurrence – a peak on the map represents a higher value of the indicator in question. The population relevance of each sentinel site, as determined in the stratified last stage random sample, combines with geography (inverse-distance weighting to provide a population-weighted extension of each colour. This transforms the map to show population space rather than simply geographic space. Results Maps allowed discussion of strategies to reduce violence against women in a context of political sensitivity about quoting summary indicator figures. Time-series maps showed planners how experiences of health services had deteriorated despite a reform programme; where in a country HIV risk behaviours were improving; and how knowledge of an economic development programme quickly fell off across a region. Change maps highlighted where indicators were improving and where they were deteriorating. Maps of potential impact of interventions, based on multivariate modelling, displayed how partial and full implementation of programmes could improve outcomes across a country. Scale depends on context. To support local planning, district maps or local government authority maps of health indicators were more useful than national maps; but multinational maps of outcomes were more useful for regional institutions. Mapping was useful to illustrate in which districts enrolment in religious schools – a rare occurrence - was more prevalent. Conclusions Population weighted raster maps can present social audit findings in an accessible and compelling

  19. Genetic linkage mapping in an F2 perennial ryegrass population using DArT markers

    DEFF Research Database (Denmark)

    Tomaszewski, Céline; Byrne, Stephen; Foito, Alexandra

    2012-01-01

    T markers, and a DArT array has recently been developed for the Lolium-Festuca complex. In this study, we report the first use of the DArTFest array to generate a genetic linkage map based on 326 markers in a Lolium perenne F2 population, consisting of 325 genotypes. For proof of concept, the map was used...

  20. Global Rural-Urban Mapping Project, Version 1 (GRUMPv1): Population Density Grid

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Rural-Urban Mapping Project, Version 1 (GRUMPv1) consists of estimates of human population for the years 1990, 1995, and 2000 by 30 arc-second (1km) grid....

  1. Global Rural-Urban Mapping Project, Version 1 (GRUMPv1): Population Count Grid

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Rural-Urban Mapping Project, Version 1 (GRUMPv1) consists of estimates of human population for the years 1990, 1995, and 2000 by 30 arc-second (1km) grid...

  2. Inbred decorated crickets exhibit higher measures of macroparasitic immunity than outbred individuals.

    Science.gov (United States)

    Gershman, S N; Barnett, C A; Pettinger, A M; Weddle, C B; Hunt, J; Sakaluk, S K

    2010-09-01

    Inbreeding is assumed to have negative effects on fitness, including the reduced ability to withstand immune challenges. We examined the immunological consequences of inbreeding in decorated crickets, Gryllodes sigillatus, by comparing lytic activity, phenoloxidase (PO) activity, and encapsulation ability of crickets from eight inbred lines with that of crickets from the outbred founder population. Surprisingly, crickets from inbred lines had a greater encapsulation ability compared with crickets from the outbred population. We suggest that because inbred crickets have reduced reproductive effort, they may, therefore, have the option of devoting more resources to this form of immunity than outbred individuals. We also found that both inbred and outbred females had higher immunity than males in PO activity and implant darkness. This result supports the hypothesis that females should devote more effort to somatic maintenance and immunity than males. PO activity and implant darkness were heritable in both males and females, but lytic activity was only heritable in females. Males and females differed in the heritability of, and genetic correlations among, immune traits, suggesting that differences in selective pressures on males and females may have resulted in a sexual conflict over optimal immune trait values.

  3. QTL Mapping in Three Connected Populations Reveals a Set of Consensus Genomic Regions for Low Temperature Germination Ability in Zea mays L.

    Science.gov (United States)

    Li, Xuhui; Wang, Guihua; Fu, Junjie; Li, Li; Jia, Guangyao; Ren, Lisha; Lubberstedt, Thomas; Wang, Guoying; Wang, Jianhua; Gu, Riliang

    2018-01-01

    Improving seed vigor in response to cold stress is an important breeding objective in maize that allows early sowing. Using two cold tolerant inbred lines 220 and P9-10 and two susceptible lines Y1518 and PH4CV, three connected F2:3 populations were generated for detecting quantitative trait locus (QTL) related to seed low-temperature germination ability. At 10°C, two germination traits (emergence rate and germination index) were collected from a sand bed and three seedling traits (seedling root length, shoot length, and total length) were extracted from paper rolls. Significant correlations were found among all traits in all populations. Via single-population analysis, 43 QTL were detected with explained phenotypic variance of 0.62%∼39.44%. Seventeen QTL explained more than 10% phenotypic variance; of them sixteen (94.12%) inherited favorable alleles from the tolerant lines. After constructing a consensus map, three meta-QTL (mQTL) were identified to include at least two initial QTL from different populations. mQTL1-1 included seven initial QTL for both germination and seedling traits; with three explaining more than 30% phenotypic variance. mQTL2-1 and mQTL9-1 covered two to three initial QTL. The favorable alleles of the QTL within these three mQTL regions were all inherited from the tolerant line 220 and P9-10. These results provided a basis for cloning of genes underlying the mQTL regions to uncover the molecular mechanisms of maize cold tolerance during germination. PMID:29445387

  4. QTL Mapping in Three Connected Populations Reveals a Set of Consensus Genomic Regions for Low Temperature Germination Ability in Zea mays L.

    Directory of Open Access Journals (Sweden)

    Xuhui Li

    2018-01-01

    Full Text Available Improving seed vigor in response to cold stress is an important breeding objective in maize that allows early sowing. Using two cold tolerant inbred lines 220 and P9-10 and two susceptible lines Y1518 and PH4CV, three connected F2:3 populations were generated for detecting quantitative trait locus (QTL related to seed low-temperature germination ability. At 10°C, two germination traits (emergence rate and germination index were collected from a sand bed and three seedling traits (seedling root length, shoot length, and total length were extracted from paper rolls. Significant correlations were found among all traits in all populations. Via single-population analysis, 43 QTL were detected with explained phenotypic variance of 0.62%∼39.44%. Seventeen QTL explained more than 10% phenotypic variance; of them sixteen (94.12% inherited favorable alleles from the tolerant lines. After constructing a consensus map, three meta-QTL (mQTL were identified to include at least two initial QTL from different populations. mQTL1-1 included seven initial QTL for both germination and seedling traits; with three explaining more than 30% phenotypic variance. mQTL2-1 and mQTL9-1 covered two to three initial QTL. The favorable alleles of the QTL within these three mQTL regions were all inherited from the tolerant line 220 and P9-10. These results provided a basis for cloning of genes underlying the mQTL regions to uncover the molecular mechanisms of maize cold tolerance during germination.

  5. Single nucleotide polymorphism of the growth hormone (GH encoding gene in inbred and outbred domestic rabbits

    Directory of Open Access Journals (Sweden)

    Deyana Gencheva Hristova

    2018-03-01

    Full Text Available Taking into consideration that the growth hormone (GH gene in rabbits is a candidate for meat production, understanding the genetic diversity and variation in this locus is of particular relevance. The present study comprised 86 rabbits (Oryctolagus cuniculus divided into 3 groups: New Zealand White (NZW outbred rabbits; first-generation inbred rabbits (F1 and second-generation inbred rabbits (F2. They were analysed by polymerase chain reaction-based restriction fragment length polymorphism method. A 231 bp fragment of the polymorphic site of the GH gene was digested with Bsh1236 restriction enzyme. Single nucleotide polymorphisms for the studied GH locus corresponding to 3 genotypes were detected in the studied rabbit populations: CC, CT and TT. In the synthetic inbred F1 and F2 populations, the frequency of the heterozygous genotype CT was 0.696 and 0.609, respectively, while for the homozygous CC genotype the frequency was lower (0.043 and 0.000, and respective values for the homozygous TT genotype were 0.261 and 0.391. This presumed a preponderance of the T allele (0.609 and 0.696 over the C allele (0.391 and 0.304 in these groups. In outbred rabbits, the allele frequencies were 0.613 (allele C and 0.387 (allele Т; consequently, the frequency of the homozygous CC genotype was higher than that of the homozygous TT genotype (0.300 vs. 0.075. Observed heterozygosity for the GH gene was higher than expected, and the result was therefore a negative inbreeding coefficient (Fis=–0.317 for outbred NZW rabbits; –0.460 for inbred F1 and –0.438 for inbred F2, indicating a sufficient number of heterozygous forms in all studied groups of rabbits. The application of narrow inbreeding by breeding full sibs in the synthetic population did not cause a rapid increase in homozygosity.

  6. High Resolution Population Distribution Maps for Southeast Asia in 2010 and 2015

    OpenAIRE

    Gaughan, Andrea E.; Stevens, Forrest R.; Linard, Catherine; Jia, Peng; Tatem, Andrew J.

    2013-01-01

    Spatially accurate, contemporary data on human population distributions are vitally important to many applied and theoretical researchers. The Southeast Asia region has undergone rapid urbanization and population growth over the past decade, yet existing spatial population distribution datasets covering the region are based principally on population count data from censuses circa 2000, with often insufficient spatial resolution or input data to map settlements precisely. Here we outline appro...

  7. A Random-Model Approach to QTL Mapping in Multiparent Advanced Generation Intercross (MAGIC) Populations.

    Science.gov (United States)

    Wei, Julong; Xu, Shizhong

    2016-02-01

    Most standard QTL mapping procedures apply to populations derived from the cross of two parents. QTL detected from such biparental populations are rarely relevant to breeding programs because of the narrow genetic basis: only two alleles are involved per locus. To improve the generality and applicability of mapping results, QTL should be detected using populations initiated from multiple parents, such as the multiparent advanced generation intercross (MAGIC) populations. The greatest challenges of QTL mapping in MAGIC populations come from multiple founder alleles and control of the genetic background information. We developed a random-model methodology by treating the founder effects of each locus as random effects following a normal distribution with a locus-specific variance. We also fit a polygenic effect to the model to control the genetic background. To improve the statistical power for a scanned marker, we release the marker effect absorbed by the polygene back to the model. In contrast to the fixed-model approach, we estimate and test the variance of each locus and scan the entire genome one locus at a time using likelihood-ratio test statistics. Simulation studies showed that this method can increase statistical power and reduce type I error compared with composite interval mapping (CIM) and multiparent whole-genome average interval mapping (MPWGAIM). We demonstrated the method using a public Arabidopsis thaliana MAGIC population and a mouse MAGIC population. Copyright © 2016 by the Genetics Society of America.

  8. Admixture analysis of stocked brown trout populations using mapped microsatellite DNA markers: indigenous trout persist in introgressed populations

    DEFF Research Database (Denmark)

    Hansen, Michael Møller; Mensberg, Karen-Lise Dons

    2009-01-01

    , but resolution is low if genetic differentiation is weak. Here, we analyse stocked brown trout populations represented by historical (1943-1956) and contemporary (2000s) samples, where genetic differentiation between wild populations and stocked trout is weak (pair-wise F-ST of 0.047 and 0.053). By analysing...... a high number of microsatellite DNA markers (50) and making use of linkage map information, we achieve clear identification of admixed and non-admixed trout. Moreover, despite strong population-level admixture by hatchery strain trout in one of the populations (70.8%), non-admixed individuals...

  9. The frequency of allelic lethals and complementation maps in natural populations of drosophila melanogaster from Mexico

    Directory of Open Access Journals (Sweden)

    Salceda Victor M.

    2004-01-01

    Full Text Available Departing from a previous study on the genetic loads affecting the second chromosome of Drosophila melanogaster in four natural populations, 171 lethal chromosomes were recovered and maintained as a balanced stocks in the condition Cy L / 1 (l=lethal; of those lethais 24 correspond to population A, 50 to populations B and C and 47 to population D. later on an intra-population allelism test for the four populations was performed for each one. A total of 3807 inter lethal crosses were done yielding a total of i 10 allelic combinations, from them the respective percentage of allelism for each population was calculated and they are as follow: 3.98 % for population A, 1.80 % for population B, 3.67 % for population C and 2.96 % for population D. the observed values for the frequency of allelism in these populations are not significantly different from those reported by other authors in similar studies in natural and/or experimental populations. Beside these values the frequency for singles, doubles, triplets and even quadruplets present in each population were determined, they shown the presence of various complementation maps due to the clustering of few different lethals: also a large complementation map formed by a large cluster involving the presence of 26 different lethals found in population D all of them combined constituting a single unit was found.

  10. ActionMap: A web-based software that automates loci assignments to framework maps.

    Science.gov (United States)

    Albini, Guillaume; Falque, Matthieu; Joets, Johann

    2003-07-01

    Genetic linkage computation may be a repetitive and time consuming task, especially when numerous loci are assigned to a framework map. We thus developed ActionMap, a web-based software that automates genetic mapping on a fixed framework map without adding the new markers to the map. Using this tool, hundreds of loci may be automatically assigned to the framework in a single process. ActionMap was initially developed to map numerous ESTs with a small plant mapping population and is limited to inbred lines and backcrosses. ActionMap is highly configurable and consists of Perl and PHP scripts that automate command steps for the MapMaker program. A set of web forms were designed for data import and mapping settings. Results of automatic mapping can be displayed as tables or drawings of maps and may be exported. The user may create personal access-restricted projects to store raw data, settings and mapping results. All data may be edited, updated or deleted. ActionMap may be used either online or downloaded for free (http://moulon.inra.fr/~bioinfo/).

  11. Initial locomotor sensitivity to cocaine varies widely among inbred mouse strains.

    Science.gov (United States)

    Wiltshire, T; Ervin, R B; Duan, H; Bogue, M A; Zamboni, W C; Cook, S; Chung, W; Zou, F; Tarantino, L M

    2015-03-01

    Initial sensitivity to psychostimulants can predict subsequent use and abuse in humans. Acute locomotor activation in response to psychostimulants is commonly used as an animal model of initial drug sensitivity and has been shown to have a substantial genetic component. Identifying the specific genetic differences that lead to phenotypic differences in initial drug sensitivity can advance our understanding of the processes that lead to addiction. Phenotyping inbred mouse strain panels are frequently used as a first step for studying the genetic architecture of complex traits. We assessed locomotor activation following a single, acute 20 mg/kg dose of cocaine (COC) in males from 45 inbred mouse strains and observed significant phenotypic variation across strains indicating a substantial genetic component. We also measured levels of COC, the active metabolite, norcocaine and the major inactive metabolite, benzoylecgonine, in plasma and brain in the same set of inbred strains. Pharmacokinetic (PK) and behavioral data were significantly correlated, but at a level that indicates that PK alone does not account for the behavioral differences observed across strains. Phenotypic data from this reference population of inbred strains can be utilized in studies aimed at examining the role of psychostimulant-induced locomotor activation on drug reward and reinforcement and to test theories about addiction processes. Moreover, these data serve as a starting point for identifying genes that alter sensitivity to the locomotor stimulatory effects of COC. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  12. Population structure and association mapping studies for important ...

    Indian Academy of Sciences (India)

    2014-12-18

    Dec 18, 2014 ... The Q matrix was constructed following the model-based approach as described by Pritchard et al. (2000) and Falush et al. (2003) which is implemented in the software Structure (Pritchard et al. 2000; http://pritch.bsd.uchicago.edu). For analysis of the data, set parameters of the population admixture model.

  13. QTL mapping for combining ability in different population-based ...

    Indian Academy of Sciences (India)

    2013-12-13

    Dec 13, 2013 ... Abstract. The NCII design (North Carolina mating design II) has been widely applied in studies of combining ability and heterosis. The objective of our research was to estimate how different base populations, sample sizes, testcross numbers and heritability influence QTL analyses of combining ability and ...

  14. QTL mapping for combining ability in different population-based ...

    Indian Academy of Sciences (India)

    The NCII design (North Carolina mating design II) has been widely applied in studies of combining ability and heterosis. The objective of our research was to estimate how different base populations, sample sizes, testcross numbers and heritability influence QTL analyses of combining ability and heterosis. A series of Monte ...

  15. Determining phenological patterns associated with the onset of senescence in a wheat MAGIC mapping population

    Directory of Open Access Journals (Sweden)

    Anyela Valentina Camargo Rodriguez

    2016-10-01

    Full Text Available The appropriate timing of developmental transitions is critical for adapting many crops to their local climatic conditions. Therefore, understanding the genetic basis of different aspects of phenology could be useful in highlighting mechanisms underpinning adaptation, with implications in breeding for climate change. For bread wheat (Triticum aestivum, the transition from vegetative to reproductive growth, the start and rate of leaf senescence and the relative timing of different stages of flowering and grain filling all contribute to plant performance. In this study we screened under Smart house conditions a large, multi-founder ‘NIAB elite MAGIC’ wheat population, to evaluate the genetic elements that influence the timing of developmental stages in European elite varieties. This panel of recombinant inbred lines was derived from eight parents that are or recently have been grown commercially in the UK and Northern Europe. We undertook a detailed temporal phenotypic analysis under Smart house conditions of the population and its parents, to try to identify known or novel Quantitative Trait Loci associated with variation in the timing of key phenological stages in senescence. This analysis resulted in the detection of QTL interactions with novel traits such the time between ‘half of ear emergence above flag leaf ligule’ and the onset of senescence at the flag leaf as well as traits associated with plant morphology such as stem height. In addition, strong correlations between several traits and the onset of senescence of the flag leaf were identified. This work establishes the value of systematically phenotyping genetically unstructured populations to reveal the genetic architecture underlying morphological variation in commercial wheat.

  16. Determining Phenological Patterns Associated with the Onset of Senescence in a Wheat MAGIC Mapping Population

    Science.gov (United States)

    Camargo, Anyela V.; Mott, Richard; Gardner, Keith A.; Mackay, Ian J.; Corke, Fiona; Doonan, John H.; Kim, Jan T.; Bentley, Alison R.

    2016-01-01

    The appropriate timing of developmental transitions is critical for adapting many crops to their local climatic conditions. Therefore, understanding the genetic basis of different aspects of phenology could be useful in highlighting mechanisms underpinning adaptation, with implications in breeding for climate change. For bread wheat (Triticum aestivum), the transition from vegetative to reproductive growth, the start and rate of leaf senescence and the relative timing of different stages of flowering and grain filling all contribute to plant performance. In this study we screened under Smart house conditions a large, multi-founder “NIAB elite MAGIC” wheat population, to evaluate the genetic elements that influence the timing of developmental stages in European elite varieties. This panel of recombinant inbred lines was derived from eight parents that are or recently have been grown commercially in the UK and Northern Europe. We undertook a detailed temporal phenotypic analysis under Smart house conditions of the population and its parents, to try to identify known or novel Quantitative Trait Loci associated with variation in the timing of key phenological stages in senescence. This analysis resulted in the detection of QTL interactions with novel traits such the time between “half of ear emergence above flag leaf ligule” and the onset of senescence at the flag leaf as well as traits associated with plant morphology such as stem height. In addition, strong correlations between several traits and the onset of senescence of the flag leaf were identified. This work establishes the value of systematically phenotyping genetically unstructured populations to reveal the genetic architecture underlying morphological variation in commercial wheat. PMID:27822218

  17. Construction of an almond linkage map in an Australian population Nonpareil × Lauranne

    Science.gov (United States)

    2010-01-01

    Background Despite a high genetic similarity to peach, almonds (Prunus dulcis) have a fleshless fruit and edible kernel, produced as a crop for human consumption. While the release of peach genome v1.0 provides an excellent opportunity for almond genetic and genomic studies, well-assessed segregating populations and the respective saturated genetic linkage maps lay the foundation for such studies to be completed in almond. Results Using an almond intraspecific cross between 'Nonpareil' and 'Lauranne' (N × L), we constructed a moderately saturated map with SSRs, SNPs, ISSRs and RAPDs. The N × L map covered 591.4 cM of the genome with 157 loci. The average marker distance of the map was 4.0 cM. The map displayed high synteny and colinearity with the Prunus T × E reference map in all eight linkage groups (G1-G8). The positions of 14 mapped gene-anchored SNPs corresponded approximately with the positions of homologous sequences in the peach genome v1.0. Analysis of Mendelian segregation ratios showed that 17.9% of markers had significantly skewed genotype ratios at the level of P Prunus reference map and peach genome V1.0. Therefore, the well-assessed almond population reported here can be used to investigate the traits of interest under Australian growing conditions, and provides more information on the almond genome for the international community. PMID:20932335

  18. (Gossypium hirsutum L. race latifolium H.) cultivars and inbred lines ...

    African Journals Online (AJOL)

    Jane

    2010-12-13

    Dec 13, 2010 ... (L) Inbred line. Numbers from 10 to 21 refer to the four cultivars and eight inbred lines from US introduced in Mozambique in 2006. Table 2. Decamer arbritary primers used for DNA amplification. Primer. Nucleotide sequence (5' – 3'). Primer. Nucleotide sequence (5' – 3'). OPA-11. CAA TCG CCG T. OPF-16.

  19. Selection of maize inbred lines and gene expression for resistance to ear rot.

    Science.gov (United States)

    Pereira, G S; Pinho, R G V; Pinho, E V R V; Pires, L P M; Bernardo Junior, L A Y; Pereira, J L A; Melo, M P

    2017-07-06

    In recent years, there has been a large incidence of fungi causing "ear rot" in maize in Brazil, the main fungus being Fusarium verticillioides. The most efficient and competitive alternative for control of this disease consists of using maize hybrids resistant to this pathogen. Thus, the aims of this study were to analyze the genetic variability of maize inbred lines in regard to resistance to ear rot to observe if there is a maternal effect to resistance to ear rot, to study genetic control of the traits evaluated in hybrids originating from inbred lines of the maize breeding program at the Agriculture Department of Universidade Federal de Lavras (Lavras, MG, Brazil), and characterize the gene expression pattern related to the plant defense mechanism against F. verticillioides. High genetic availability was observed for resistance to this disease among the inbred lines evaluated. Considering combined diallel analysis, it was observed that the mean square of general combining ability (GCA) was not significant for the characteristic under study. However, specific combining ability (SCA) was significant, which indicates the predominance of non-additive effects involved in control of the characteristic for the population evaluated. A maternal effect was not observed for the characteristic of ear rot resistance in this study. Inbred lines 22, 58, and 91 showed potential for use in breeding programs aiming at resistance to F. verticillioides. Only two genes, LOX8 and Hsp82, had a satisfactory result that was able to be related to a plant defense mechanism when there is ear rot infection, though expression of these genes was observed in only one susceptible genotype. Thus, the genes LOX8 and Hsp82 are potential molecular markers for selection of maize inbred lines resistant to F. verticillioides.

  20. An Atlas of ShakeMaps and population exposure catalog for earthquake loss modeling

    Science.gov (United States)

    Allen, T.I.; Wald, D.J.; Earle, P.S.; Marano, K.D.; Hotovec, A.J.; Lin, K.; Hearne, M.G.

    2009-01-01

    We present an Atlas of ShakeMaps and a catalog of human population exposures to moderate-to-strong ground shaking (EXPO-CAT) for recent historical earthquakes (1973-2007). The common purpose of the Atlas and exposure catalog is to calibrate earthquake loss models to be used in the US Geological Survey's Prompt Assessment of Global Earthquakes for Response (PAGER). The full ShakeMap Atlas currently comprises over 5,600 earthquakes from January 1973 through December 2007, with almost 500 of these maps constrained-to varying degrees-by instrumental ground motions, macroseismic intensity data, community internet intensity observations, and published earthquake rupture models. The catalog of human exposures is derived using current PAGER methodologies. Exposure to discrete levels of shaking intensity is obtained by correlating Atlas ShakeMaps with a global population database. Combining this population exposure dataset with historical earthquake loss data, such as PAGER-CAT, provides a useful resource for calibrating loss methodologies against a systematically-derived set of ShakeMap hazard outputs. We illustrate two example uses for EXPO-CAT; (1) simple objective ranking of country vulnerability to earthquakes, and; (2) the influence of time-of-day on earthquake mortality. In general, we observe that countries in similar geographic regions with similar construction practices tend to cluster spatially in terms of relative vulnerability. We also find little quantitative evidence to suggest that time-of-day is a significant factor in earthquake mortality. Moreover, earthquake mortality appears to be more systematically linked to the population exposed to severe ground shaking (Modified Mercalli Intensity VIII+). Finally, equipped with the full Atlas of ShakeMaps, we merge each of these maps and find the maximum estimated peak ground acceleration at any grid point in the world for the past 35 years. We subsequently compare this "composite ShakeMap" with existing global

  1. Longevity-Determining Genes in Caenorhabditis Elegans: Chromosomal Mapping of Multiple Noninteractive Loci

    OpenAIRE

    Ebert-II, R. H.; Cherkasova, V. A.; Dennis, R. A.; Wu, J. H.; Ruggles, S.; Perrin, T. E.; Shmookler-Reis, R. J.

    1993-01-01

    We have used chromosome mapping with polymorphic markers to define genetic components governing life span in the nematode Caenorhabditis elegans. A complex recombinant-inbred population was derived from an interstrain cross, yielding >1000 genotypes, each a composite of homozygous segments from the two parental strains. Genotypes were analyzed for the last-surviving 1-5% of worms in aging cohorts, and for young controls, by multiplex polymerase chain reaction using polymorphic markers to dist...

  2. High-density genetic linkage map construction and QTL mapping of grain shape and size in the wheat population Yanda1817 × Beinong6.

    Directory of Open Access Journals (Sweden)

    Qiu-Hong Wu

    Full Text Available High-density genetic linkage maps are necessary for precisely mapping quantitative trait loci (QTLs controlling grain shape and size in wheat. By applying the Infinium iSelect 9K SNP assay, we have constructed a high-density genetic linkage map with 269 F 8 recombinant inbred lines (RILs developed between a Chinese cornerstone wheat breeding parental line Yanda1817 and a high-yielding line Beinong6. The map contains 2431 SNPs and 128 SSR & EST-SSR markers in a total coverage of 3213.2 cM with an average interval of 1.26 cM per marker. Eighty-eight QTLs for thousand-grain weight (TGW, grain length (GL, grain width (GW and grain thickness (GT were detected in nine ecological environments (Beijing, Shijiazhuang and Kaifeng during five years between 2010-2014 by inclusive composite interval mapping (ICIM (LOD ≥ 2.5. Among which, 17 QTLs for TGW were mapped on chromosomes 1A, 1B, 2A, 2B, 3A, 3B, 3D, 4A, 4D, 5A, 5B and 6B with phenotypic variations ranging from 2.62% to 12.08%. Four stable QTLs for TGW could be detected in five and seven environments, respectively. Thirty-two QTLs for GL were mapped on chromosomes 1B, 1D, 2A, 2B, 2D, 3B, 3D, 4A, 4B, 4D, 5A, 5B, 6B, 7A and 7B, with phenotypic variations ranging from 2.62% to 44.39%. QGl.cau-2A.2 can be detected in all the environments with the largest phenotypic variations, indicating that it is a major and stable QTL. For GW, 12 QTLs were identified with phenotypic variations range from 3.69% to 12.30%. We found 27 QTLs for GT with phenotypic variations ranged from 2.55% to 36.42%. In particular, QTL QGt.cau-5A.1 with phenotypic variations of 6.82-23.59% was detected in all the nine environments. Moreover, pleiotropic effects were detected for several QTL loci responsible for grain shape and size that could serve as target regions for fine mapping and marker assisted selection in wheat breeding programs.

  3. High Resolution Population Distribution Maps for Southeast Asia in 2010 and 2015

    Science.gov (United States)

    Gaughan, Andrea E.; Stevens, Forrest R.; Linard, Catherine; Jia, Peng; Tatem, Andrew J.

    2013-01-01

    Spatially accurate, contemporary data on human population distributions are vitally important to many applied and theoretical researchers. The Southeast Asia region has undergone rapid urbanization and population growth over the past decade, yet existing spatial population distribution datasets covering the region are based principally on population count data from censuses circa 2000, with often insufficient spatial resolution or input data to map settlements precisely. Here we outline approaches to construct a database of GIS-linked circa 2010 census data and methods used to construct fine-scale (∼100 meters spatial resolution) population distribution datasets for each country in the Southeast Asia region. Landsat-derived settlement maps and land cover information were combined with ancillary datasets on infrastructure to model population distributions for 2010 and 2015. These products were compared with those from two other methods used to construct commonly used global population datasets. Results indicate mapping accuracies are consistently higher when incorporating land cover and settlement information into the AsiaPop modelling process. Using existing data, it is possible to produce detailed, contemporary and easily updatable population distribution datasets for Southeast Asia. The 2010 and 2015 datasets produced are freely available as a product of the AsiaPop Project and can be downloaded from: www.asiapop.org. PMID:23418469

  4. High resolution population distribution maps for Southeast Asia in 2010 and 2015.

    Directory of Open Access Journals (Sweden)

    Andrea E Gaughan

    Full Text Available Spatially accurate, contemporary data on human population distributions are vitally important to many applied and theoretical researchers. The Southeast Asia region has undergone rapid urbanization and population growth over the past decade, yet existing spatial population distribution datasets covering the region are based principally on population count data from censuses circa 2000, with often insufficient spatial resolution or input data to map settlements precisely. Here we outline approaches to construct a database of GIS-linked circa 2010 census data and methods used to construct fine-scale (∼100 meters spatial resolution population distribution datasets for each country in the Southeast Asia region. Landsat-derived settlement maps and land cover information were combined with ancillary datasets on infrastructure to model population distributions for 2010 and 2015. These products were compared with those from two other methods used to construct commonly used global population datasets. Results indicate mapping accuracies are consistently higher when incorporating land cover and settlement information into the AsiaPop modelling process. Using existing data, it is possible to produce detailed, contemporary and easily updatable population distribution datasets for Southeast Asia. The 2010 and 2015 datasets produced are freely available as a product of the AsiaPop Project and can be downloaded from: www.asiapop.org.

  5. High resolution population distribution maps for Southeast Asia in 2010 and 2015.

    Science.gov (United States)

    Gaughan, Andrea E; Stevens, Forrest R; Linard, Catherine; Jia, Peng; Tatem, Andrew J

    2013-01-01

    Spatially accurate, contemporary data on human population distributions are vitally important to many applied and theoretical researchers. The Southeast Asia region has undergone rapid urbanization and population growth over the past decade, yet existing spatial population distribution datasets covering the region are based principally on population count data from censuses circa 2000, with often insufficient spatial resolution or input data to map settlements precisely. Here we outline approaches to construct a database of GIS-linked circa 2010 census data and methods used to construct fine-scale (∼100 meters spatial resolution) population distribution datasets for each country in the Southeast Asia region. Landsat-derived settlement maps and land cover information were combined with ancillary datasets on infrastructure to model population distributions for 2010 and 2015. These products were compared with those from two other methods used to construct commonly used global population datasets. Results indicate mapping accuracies are consistently higher when incorporating land cover and settlement information into the AsiaPop modelling process. Using existing data, it is possible to produce detailed, contemporary and easily updatable population distribution datasets for Southeast Asia. The 2010 and 2015 datasets produced are freely available as a product of the AsiaPop Project and can be downloaded from: www.asiapop.org.

  6. Evaluation of Intrinsic Water Use Efficiency and Ecophysiological Modelling on a Potato Dihaploid Mapping Population

    DEFF Research Database (Denmark)

    Topbjerg, Henrik Bak

    of the solution the crop has to be able to tolerate drought. In this study, a dihaploid potato mapping population has been used to investigate clonal performance in intrinsic water use efficiency (WUEi) under progressive drought achieved in greenhouse and under field conditions. The mapping population revealed...... progression in the development of drought tolerant crop cultivars, faster screening methods have to be developed. Here, it was found that the chlorophyll content index could be a useful screening method for higher WUEi under greenhouse conditions. However, such methods must rely on physiological trait...... evaluation in conjunction with agronomical trait evaluation....

  7. Method for mapping population-based case-control studies: an application using generalized additive models

    Directory of Open Access Journals (Sweden)

    Aschengrau Ann

    2006-06-01

    Full Text Available Abstract Background Mapping spatial distributions of disease occurrence and risk can serve as a useful tool for identifying exposures of public health concern. Disease registry data are often mapped by town or county of diagnosis and contain limited data on covariates. These maps often possess poor spatial resolution, the potential for spatial confounding, and the inability to consider latency. Population-based case-control studies can provide detailed information on residential history and covariates. Results Generalized additive models (GAMs provide a useful framework for mapping point-based epidemiologic data. Smoothing on location while controlling for covariates produces adjusted maps. We generate maps of odds ratios using the entire study area as a reference. We smooth using a locally weighted regression smoother (loess, a method that combines the advantages of nearest neighbor and kernel methods. We choose an optimal degree of smoothing by minimizing Akaike's Information Criterion. We use a deviance-based test to assess the overall importance of location in the model and pointwise permutation tests to locate regions of significantly increased or decreased risk. The method is illustrated with synthetic data and data from a population-based case-control study, using S-Plus and ArcView software. Conclusion Our goal is to develop practical methods for mapping population-based case-control and cohort studies. The method described here performs well for our synthetic data, reproducing important features of the data and adequately controlling the covariate. When applied to the population-based case-control data set, the method suggests spatial confounding and identifies statistically significant areas of increased and decreased odds ratios.

  8. Construction of an almond linkage map in an Australian population Nonpareil × Lauranne

    Directory of Open Access Journals (Sweden)

    Gibson John P

    2010-10-01

    Full Text Available Abstract Background Despite a high genetic similarity to peach, almonds (Prunus dulcis have a fleshless fruit and edible kernel, produced as a crop for human consumption. While the release of peach genome v1.0 provides an excellent opportunity for almond genetic and genomic studies, well-assessed segregating populations and the respective saturated genetic linkage maps lay the foundation for such studies to be completed in almond. Results Using an almond intraspecific cross between 'Nonpareil' and 'Lauranne' (N × L, we constructed a moderately saturated map with SSRs, SNPs, ISSRs and RAPDs. The N × L map covered 591.4 cM of the genome with 157 loci. The average marker distance of the map was 4.0 cM. The map displayed high synteny and colinearity with the Prunus T × E reference map in all eight linkage groups (G1-G8. The positions of 14 mapped gene-anchored SNPs corresponded approximately with the positions of homologous sequences in the peach genome v1.0. Analysis of Mendelian segregation ratios showed that 17.9% of markers had significantly skewed genotype ratios at the level of P ® 3 were compared, and their high degree of similarity was evident despite the positional inconsistency of a few markers. Conclusions We presented a moderately saturated Australian almond map, which is highly syntenic and collinear with the Prunus reference map and peach genome V1.0. Therefore, the well-assessed almond population reported here can be used to investigate the traits of interest under Australian growing conditions, and provides more information on the almond genome for the international community.

  9. Biplot analysis of diallel crosses of NS maize inbred lines

    Directory of Open Access Journals (Sweden)

    Boćanski Jan

    2011-01-01

    Full Text Available Genetic markers, from morphological to molecular, in function with early Heterosis is a prerequisite for the successful commercial maize production. It does not appear in any cross of two inbred lines, and therefore, the determination of combining abilities of parental lines is essential. The most commonly used method for determining combining abilities is diallel analysis. Besides conventional methods for diallel analysis, a new biplot approach has been sugested. In this paper, we studied the combining ability for grain yield in a set of genotypes obtained by diallel crossing system of six inbred lines. Both, the Griffing’s conventional method and the biplot approach have been used for diallel analysis. Comparing the GCA values from biplot analysis and Griffing’s method, similar results can be observed, with the exception of NS L 1051 and NS L 1000 whose ranks are interchanged. Biplot analysis enables the SCA estimation of parent inbred, and the highest SCA has inbred B73D. Biplot analysis also allows the estimation of the best crosses. Inbred B73D shows the best results when crossed with testers Mo17Ht, NS L 1051 and N152, inbred N152 combines best with testers NS L 1001 and NS L 1000, whereas the cross of inbred NS L 1051 with tester B73D results with the highest grain yield per plant in comparison with other testers.

  10. Multipoint-likelihood maximization mapping on 4 segregating populations to achieve an integrated framework map for QTL analysis in pot azalea (Rhododendron simsii hybrids

    Directory of Open Access Journals (Sweden)

    Van Bockstaele Erik

    2010-01-01

    Full Text Available Abstract Background Azalea (Rhododendron simsii hybrids is the most important flowering pot plant produced in Belgium, being exported world-wide. In the breeding program, flower color is the main feature for selection, only in later stages cultivation related plant quality traits are evaluated. As a result, plants with attractive flowering are kept too long in the breeding cycle. The inheritance of flower color has been well studied; information on the heritability of cultivation related quality traits is lacking. For this purpose, QTL mapping in diverse genetic backgrounds appeared to be a must and therefore 4 mapping populations were made and analyzed. Results An integrated framework map on four individual linkage maps in Rhododendron simsii hybrids was constructed. For genotyping, mainly dominant scored AFLP (on average 364 per population and MYB-based markers (15 were combined with co-dominant SSR (23 and EST markers (12. Linkage groups were estimated in JoinMap. A consensus grouping for the 4 mapping populations was made and applied in each individual mapping population. Finally, 16 stable linkage groups were set for the 4 populations; the azalea chromosome number being 13. A combination of regression mapping (JoinMap and multipoint-likelihood maximization (Carthagène enabled the construction of 4 maps and their alignment. A large portion of loci (43% was common to at least two populations and could therefore serve as bridging markers. The different steps taken for map optimization and integration into a reference framework map for QTL mapping are discussed. Conclusions This is the first map of azalea up to our knowledge. AFLP and SSR markers are used as a reference backbone and functional markers (EST and MYB were added as candidate genes for QTL analysis. The alignment of the 4 maps on the basis of framework markers will facilitate in turn the alignment of QTL regions detected in each of the populations. The approach we took is

  11. QTL mapping for test weight by using F2: 3 population in maize

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 90; Issue 1. QTL mapping for test weight by using F2:3 population in maize. Jun-Qiang Ding Jin-Liang ... In the years 2007 and 2008, a F2:3 population along with the parents Chang7-2 and Zheng58 were planted in Zhengzhou, People's Republic of China. Significant genotypic ...

  12. Identification of milling and baking quality QTL in multiple soft wheat mapping populations.

    Science.gov (United States)

    Cabrera, Antonio; Guttieri, Mary; Smith, Nathan; Souza, Edward; Sturbaum, Anne; Hua, Duc; Griffey, Carl; Barnett, Marla; Murphy, Paul; Ohm, Herb; Uphaus, Jim; Sorrells, Mark; Heffner, Elliot; Brown-Guedira, Gina; Van Sanford, David; Sneller, Clay

    2015-11-01

    Two mapping approaches were use to identify and validate milling and baking quality QTL in soft wheat. Two LG were consistently found important for multiple traits and we recommend the use marker-assisted selection on specific markers reported here. Wheat-derived food products require a range of characteristics. Identification and understanding of the genetic components controlling end-use quality of wheat is important for crop improvement. We assessed the underlying genetics controlling specific milling and baking quality parameters of soft wheat including flour yield, softness equivalent, flour protein, sucrose, sodium carbonate, water absorption and lactic acid, solvent retention capacities in a diversity panel and five bi-parental mapping populations. The populations were genotyped with SSR and DArT markers, with markers specific for the 1BL.1RS translocation and sucrose synthase gene. Association analysis and composite interval mapping were performed to identify quantitative trait loci (QTL). High heritability was observed for each of the traits evaluated, trait correlations were consistent over populations, and transgressive segregants were common in all bi-parental populations. A total of 26 regions were identified as potential QTL in the diversity panel and 74 QTL were identified across all five bi-parental mapping populations. Collinearity of QTL from chromosomes 1B and 2B was observed across mapping populations and was consistent with results from the association analysis in the diversity panel. Multiple regression analysis showed the importance of the two 1B and 2B regions and marker-assisted selection for the favorable alleles at these regions should improve quality.

  13. Association mapping in multiple segregating populations of sugar beet (Beta vulgaris L.).

    Science.gov (United States)

    Stich, Benjamin; Melchinger, Albrecht E; Heckenberger, Martin; Möhring, Jens; Schechert, Axel; Piepho, Hans-Peter

    2008-11-01

    Association mapping in multiple segregating populations (AMMSP) combines high power to detect QTL in genome-wide approaches of linkage mapping with high mapping resolution of association mapping. The main objectives of this study were to (1) examine the applicability of AMMSP in a plant breeding context based on segregating populations of various size of sugar beet (Beta vulgaris L.), (2) compare different biometric approaches for AMMSP, and (3) detect markers with significant main effect across locations for nine traits in sugar beet. We used 768 F(n) (n = 2, 3, 4) sugar beet genotypes which were randomly derived from 19 crosses among diploid elite sugar beet clones. For all nine traits, the genotypic and genotype x location interaction variances were highly significant (P < 0.01). Using a one-step AMMSP approach, the total number of significant (P < 0.05) marker-phenotype associations was 44. The identification of genome regions associated with the traits under consideration indicated that not only segregating populations derived from crosses of parental genotypes in a systematic manner could be used for AMMSP but also populations routinely derived in plant breeding programs from multiple, related crosses. Furthermore, our results suggest that data sets, whose size does not permit analysis by the one-step AMMSP approach, might be analyzed using the two-step approach based on adjusted entry means for each location without losing too much power for detection of marker-phenotype associations.

  14. QTL mapping for test weight by using F2:3 population in maize

    Indian Academy of Sciences (India)

    ity of corn in agriculture, but also an important factor to determining the corn market grades for milling, export and other purposes. For test weight improvement in maize, devel- oping hybrids with ..... Zhang C. R. 2009 QTL mapping for yield and yield related traits using F2:3 population derived from Zhengdan 958 in maize,.

  15. Linkage mapping in a watermelon population segregating for fusarium wilt resistance

    Science.gov (United States)

    Leigh K. Hawkins; Fenny Dane; Thomas L. Kubisiak; Billy B. Rhodes; Robert L. Jarret

    2001-01-01

    Isozyme, randomly amplified polymorphic DNA (RAPD), and simple sequence repeats (SSR) markers were used to generate a linkage map in an F2 and F3 watermelon (Citrullus lanatus (Thumb.) Matsum. & Nakai) population derived from a cross between the fusarium wilt (Fusarium oxysporum f....

  16. Numerically exploring habitat fragmentation effects on populations using cell-based coupled map lattices

    Science.gov (United States)

    Michael Bevers; Curtis H. Flather

    1999-01-01

    We examine habitat size, shape, and arrangement effects on populations using a discrete reaction-diffusion model. Diffusion is modeled passively and applied to a cellular grid of territories forming a coupled map lattice. Dispersal mortality is proportional to the amount of nonhabitat and fully occupied habitat surrounding a given cell, with distance decay. After...

  17. Updating Poverty Maps of Vietnam using Vietnam Household Living Standard Survey 2002 and Population Census 1999

    OpenAIRE

    Nguyen Viet, Cuong; Van der Weide, Roy; Tran, Ngoc Truong

    2007-01-01

    Poverty map is an important for poverty targeting in developing countries. In this study, we combine the Vietnam Household Living Standard Survey (VHLSS) in 2002 and the Population Census in 1999 to estimate poverty and inequality indexes of all provinces and districts of Vietnam in the year 2002.

  18. Nested Association Mapping of Stem Rust Resistance in Wheat Using Genotyping by Sequencing.

    Directory of Open Access Journals (Sweden)

    Prabin Bajgain

    Full Text Available We combined the recently developed genotyping by sequencing (GBS method with joint mapping (also known as nested association mapping to dissect and understand the genetic architecture controlling stem rust resistance in wheat (Triticum aestivum. Ten stem rust resistant wheat varieties were crossed to the susceptible line LMPG-6 to generate F6 recombinant inbred lines. The recombinant inbred line populations were phenotyped in Kenya, South Africa, and St. Paul, Minnesota, USA. By joint mapping of the 10 populations, we identified 59 minor and medium-effect QTL (explained phenotypic variance range of 1% - 20% on 20 chromosomes that contributed towards adult plant resistance to North American Pgt races as well as the highly virulent Ug99 race group. Fifteen of the 59 QTL were detected in multiple environments. No epistatic relationship was detected among the QTL. While these numerous small- to medium-effect QTL are shared among the families, the founder parents were found to have different allelic effects for the QTL. Fourteen QTL identified by joint mapping were also detected in single-population mapping. As these QTL were mapped using SNP markers with known locations on the physical chromosomes, the genomic regions identified with QTL could be explored more in depth to discover candidate genes for stem rust resistance. The use of GBS-derived de novo SNPs in mapping resistance to stem rust shown in this study could be used as a model to conduct similar marker-trait association studies in other plant species.

  19. Nested Association Mapping of Stem Rust Resistance in Wheat Using Genotyping by Sequencing.

    Science.gov (United States)

    Bajgain, Prabin; Rouse, Matthew N; Tsilo, Toi J; Macharia, Godwin K; Bhavani, Sridhar; Jin, Yue; Anderson, James A

    2016-01-01

    We combined the recently developed genotyping by sequencing (GBS) method with joint mapping (also known as nested association mapping) to dissect and understand the genetic architecture controlling stem rust resistance in wheat (Triticum aestivum). Ten stem rust resistant wheat varieties were crossed to the susceptible line LMPG-6 to generate F6 recombinant inbred lines. The recombinant inbred line populations were phenotyped in Kenya, South Africa, and St. Paul, Minnesota, USA. By joint mapping of the 10 populations, we identified 59 minor and medium-effect QTL (explained phenotypic variance range of 1% - 20%) on 20 chromosomes that contributed towards adult plant resistance to North American Pgt races as well as the highly virulent Ug99 race group. Fifteen of the 59 QTL were detected in multiple environments. No epistatic relationship was detected among the QTL. While these numerous small- to medium-effect QTL are shared among the families, the founder parents were found to have different allelic effects for the QTL. Fourteen QTL identified by joint mapping were also detected in single-population mapping. As these QTL were mapped using SNP markers with known locations on the physical chromosomes, the genomic regions identified with QTL could be explored more in depth to discover candidate genes for stem rust resistance. The use of GBS-derived de novo SNPs in mapping resistance to stem rust shown in this study could be used as a model to conduct similar marker-trait association studies in other plant species.

  20. Numerous genetic loci identified for drought tolerance in the maize nested association mapping populations

    Science.gov (United States)

    Maize requires more water than most other crops; therefore, the water use efficiency of this crop must be improved for maize production under undesirable land and changing environmental conditions. To elucidate the genetic control of drought in maize, we evaluated approximately 5000 inbred lines fr...

  1. Reciprocal translocation of small numbers of inbred individuals rescues immunogenetic diversity.

    Science.gov (United States)

    Grueber, Catherine E; Sutton, Jolene T; Heber, Sol; Briskie, James V; Jamieson, Ian G; Robertson, Bruce C

    2017-05-01

    Genetic rescue can reduce inbreeding depression and increase fitness of small populations, even when the donor populations are highly inbred. In a recent experiment involving two inbred island populations of the New Zealand South Island robin, Petroica australis, reciprocal translocations improved microsatellite diversity and individual fitness. While microsatellite loci may reflect patterns of genome-wide diversity, they generally do not indicate the specific genetic regions responsible for increased fitness. We tested the effectiveness of this reciprocal translocation for rescuing diversity of two immunogenetic regions: Toll-like receptor (TLR) and major histocompatibility complex (MHC) genes. We found that the relatively small number of migrants (seven and ten per island) effectively brought the characteristic TLR gene diversity of each source population into the recipient population. However, when migrants transmitted TLR alleles that were already present at high frequency in the recipient population, it was possible for offspring of mixed heritage to have decreased gene diversity compared to recipient population diversity prior to translocation. In contrast to TLRs, we did not observe substantial changes in MHC allelic diversity following translocation, with limited evidence of a decrease in differentiation, perhaps because most MHC alleles were observed at both sites prior to the translocation. Overall, we conclude that small numbers of migrants may successfully restore the diversity of immunogenetic loci with few alleles, but that translocating larger numbers of animals would provide additional opportunity for the genetic rescue of highly polymorphic immunity regions, such as the MHC, even when the source population is inbred. © 2017 John Wiley & Sons Ltd.

  2. Singapore Genome Variation Project: a haplotype map of three Southeast Asian populations.

    Science.gov (United States)

    Teo, Yik-Ying; Sim, Xueling; Ong, Rick T H; Tan, Adrian K S; Chen, Jieming; Tantoso, Erwin; Small, Kerrin S; Ku, Chee-Seng; Lee, Edmund J D; Seielstad, Mark; Chia, Kee-Seng

    2009-11-01

    The Singapore Genome Variation Project (SGVP) provides a publicly available resource of 1.6 million single nucleotide polymorphisms (SNPs) genotyped in 268 individuals from the Chinese, Malay, and Indian population groups in Southeast Asia. This online database catalogs information and summaries on genotype and phased haplotype data, including allele frequencies, assessment of linkage disequilibrium (LD), and recombination rates in a format similar to the International HapMap Project. Here, we introduce this resource and describe the analysis of human genomic variation upon agglomerating data from the HapMap and the Human Genome Diversity Project, providing useful insights into the population structure of the three major population groups in Asia. In addition, this resource also surveyed across the genome for variation in regional patterns of LD between the HapMap and SGVP populations, and for signatures of positive natural selection using two well-established metrics: iHS and XP-EHH. The raw and processed genetic data, together with all population genetic summaries, are publicly available for download and browsing through a web browser modeled with the Generic Genome Browser.

  3. Plant regeneration from immature embryos of Kenyan maize inbred ...

    African Journals Online (AJOL)

    % percent of regenerants were normal and fertile. The successful regeneration of some of the inbred lines and/or hybrids provides a basis for development of genetic transformation using Agrobacterium tumefaciens to improve priority traits such ...

  4. Mapping genes governing flower architecture and pollen development in a double mutant population of carrot

    Directory of Open Access Journals (Sweden)

    Holger eBudahn

    2014-10-01

    Full Text Available A linkage map of carrot (Daucus carota L. was developed in order to study reproductive traits. The F2 mapping population derived from an initial cross between a yellow leaf (yel chlorophyll mutant and a compressed lamina (cola mutant with unique flower defects of the sporophytic parts of male and female organs. The genetic map has a total length of 781 cM and included 285 loci. The length of the nine linkage groups ranged between 65 cM and 145 cM. All linkage groups have been anchored to the reference map. The objective of this study was the generation of a well-saturated linkage map of D. carota. Mapping of the cola-locus associated with flower development and fertility was successfully demonstrated. Two MADS-box genes (DcMADS3, DcMADS5 with prominent roles in flowering and reproduction as well as three additional genes (DcAOX2a, DcAOX2b, DcCHS2 with further importance for male reproduction were assigned to different loci that did not co-segregate with the cola-locus.

  5. Biplot analysis of diallel crosses of NS maize inbred lines

    OpenAIRE

    Boćanski Jan; Nastasić Aleksandra; Stanisavljević Dušan; Srećkov Zorana; Mitrović Bojan; Treskić Sanja; Vukosavljev Mirjana

    2011-01-01

    Bocanski J., A. Nastasic, D. Stanisavljevic, Z. Sreckov, B. Mitrovic, S. Treskic and M. Vukosavljev (2011): Biplot analysis of diallel crosses of NS maize inbred lines- Genetika, Vol 43, No. 2, 277 - 284. Genetic markers, from morphological to molecular, in function with early Heterosis is a prerequisite for the successful commercial maize production. It does not appear in any cross of two inbred lines, and therefore, the determination of combining abilities of parental lines is essential. Th...

  6. Mapping of Novel QTL Regulating Grain Shattering Using Doubled Haploid Population in Rice (Oryza sativa L.)

    OpenAIRE

    Lee, Gyu-Ho; Kang, In-Kyu; Kim, Kyung-Min

    2016-01-01

    The critical evolutionary step during domestication of major cereals was elimination of seed shattering because the easy-to-shatter trait in wild relatives results in a severe reduction in yield. In this study, we analyzed the QTLs associated with shattering employing a high-density genetic map in doubled haploid (DH) population of rice (Oryza sativa L.). A genetic linkage map was generated with 217 microsatellite markers spanning 2082.4 cM and covering 12 rice chromosomes with an average int...

  7. Construction of a genome-anchored, high-density genetic map for melon (Cucumis melo L.) and identification of Fusarium oxysporum f. sp. melonis race 1 resistance QTL.

    Science.gov (United States)

    Branham, Sandra E; Levi, Amnon; Katawczik, Melanie; Fei, Zhangjun; Wechter, W Patrick

    2018-04-01

    Four QTLs and an epistatic interaction were associated with disease severity in response to inoculation with Fusarium oxysporum f. sp. melonis race 1 in a recombinant inbred line population of melon. The USDA Cucumis melo inbred line, MR-1, harbors a wealth of alleles associated with resistance to several major diseases of melon, including powdery mildew, downy mildew, Alternaria leaf blight, and Fusarium wilt. MR-1 was crossed to an Israeli cultivar, Ananas Yok'neam, which is susceptible to all of these diseases, to generate a recombinant inbred line (RIL) population of 172 lines. In this study, the RIL population was genotyped to construct an ultra-dense genetic linkage map with 5663 binned SNPs anchored to the C. melo genome and exhibits the overall high quality of the assembly. The utility of the densely genotyped population was demonstrated through QTL mapping of a well-studied trait, resistance to Fusarium wilt caused by Fusarium oxysporum f. sp. melonis (Fom) race 1. A major QTL co-located with the previously validated resistance gene Fom-2. In addition, three minor QTLs and an epistatic interaction contributing to Fom race 1 resistance were identified. The MR-1 × AY RIL population provides a valuable resource for future QTL mapping studies and marker-assisted selection of disease resistance in melon.

  8. Epidemiological geomatics in evaluation of mine risk education in Afghanistan: introducing population weighted raster maps

    Directory of Open Access Journals (Sweden)

    Andersson Neil

    2006-01-01

    Full Text Available Abstract Evaluation of mine risk education in Afghanistan used population weighted raster maps as an evaluation tool to assess mine education performance, coverage and costs. A stratified last-stage random cluster sample produced representative data on mine risk and exposure to education. Clusters were weighted by the population they represented, rather than the land area. A "friction surface" hooked the population weight into interpolation of cluster-specific indicators. The resulting population weighted raster contours offer a model of the population effects of landmine risks and risk education. Five indicator levels ordered the evidence from simple description of the population-weighted indicators (level 0, through risk analysis (levels 1–3 to modelling programme investment and local variations (level 4. Using graphic overlay techniques, it was possible to metamorphose the map, portraying the prediction of what might happen over time, based on the causality models developed in the epidemiological analysis. Based on a lattice of local site-specific predictions, each cluster being a small universe, the "average" prediction was immediately interpretable without losing the spatial complexity.

  9. QTL mapping for yield components and agronomic traits in a Brazilian soybean population

    Directory of Open Access Journals (Sweden)

    Josiane Isabela da Silva Rodrigues

    2016-11-01

    Full Text Available The objective of this work was to map QTL for agronomic traits in a Brazilian soybean population. For this, 207 F2:3 progenies from the cross CS3035PTA276-1-5-2x UFVS2012 were genotyped and cultivated in Viçosa-MG, using randomized block design with three replications. QTL detection was carried out by linear regression and composite interval mapping. Thirty molecular markers linked to QTL were detected by linear regression for the total of nine agronomic traits. QTL for SWP (seed weight per plant, W100S (weight of 100 seeds, NPP (number of pods per plant, and NSP (number of seeds per plant were detected by composite interval mapping. Four QTL with additive effect are promising for marker-assisted selection (MAS. Particularly, the markers Satt155 and Satt300 could be useful in simultaneous selection for greater SWP, NPP, and NSP.

  10. An integrated genetic map based on four mapping populations and quantitative trait loci associated with economically important traits in watermelon (Citrullus lanatus).

    Science.gov (United States)

    Ren, Yi; McGregor, Cecilia; Zhang, Yan; Gong, Guoyi; Zhang, Haiying; Guo, Shaogui; Sun, Honghe; Cai, Wantao; Zhang, Jie; Xu, Yong

    2014-01-20

    Modern watermelon (Citrullus lanatus L.) cultivars share a narrow genetic base due to many years of selection for desirable horticultural qualities. Wild subspecies within C. lanatus are important potential sources of novel alleles for watermelon breeding, but successful trait introgression into elite cultivars has had limited success. The application of marker assisted selection (MAS) in watermelon is yet to be realized, mainly due to the past lack of high quality genetic maps. Recently, a number of useful maps have become available, however these maps have few common markers, and were constructed using different marker sets, thus, making integration and comparative analysis among maps difficult. The objective of this research was to use single-nucleotide polymorphism (SNP) anchor markers to construct an integrated genetic map for C. lanatus. Under the framework of the high density genetic map, an integrated genetic map was constructed by merging data from four independent mapping experiments using a genetically diverse array of parental lines, which included three subspecies of watermelon. The 698 simple sequence repeat (SSR), 219 insertion-deletion (InDel), 36 structure variation (SV) and 386 SNP markers from the four maps were used to construct an integrated map. This integrated map contained 1339 markers, spanning 798 cM with an average marker interval of 0.6 cM. Fifty-eight previously reported quantitative trait loci (QTL) for 12 traits in these populations were also integrated into the map. In addition, new QTL identified for brix, fructose, glucose and sucrose were added. Some QTL associated with economically important traits detected in different genetic backgrounds mapped to similar genomic regions of the integrated map, suggesting that such QTL are responsible for the phenotypic variability observed in a broad array of watermelon germplasm. The integrated map described herein enhances the utility of genomic tools over previous watermelon genetic maps. A

  11. An integrated genetic map based on four mapping populations and quantitative trait loci associated with economically important traits in watermelon (Citrullus lanatus)

    Science.gov (United States)

    2014-01-01

    Background Modern watermelon (Citrullus lanatus L.) cultivars share a narrow genetic base due to many years of selection for desirable horticultural qualities. Wild subspecies within C. lanatus are important potential sources of novel alleles for watermelon breeding, but successful trait introgression into elite cultivars has had limited success. The application of marker assisted selection (MAS) in watermelon is yet to be realized, mainly due to the past lack of high quality genetic maps. Recently, a number of useful maps have become available, however these maps have few common markers, and were constructed using different marker sets, thus, making integration and comparative analysis among maps difficult. The objective of this research was to use single-nucleotide polymorphism (SNP) anchor markers to construct an integrated genetic map for C. lanatus. Results Under the framework of the high density genetic map, an integrated genetic map was constructed by merging data from four independent mapping experiments using a genetically diverse array of parental lines, which included three subspecies of watermelon. The 698 simple sequence repeat (SSR), 219 insertion-deletion (InDel), 36 structure variation (SV) and 386 SNP markers from the four maps were used to construct an integrated map. This integrated map contained 1339 markers, spanning 798 cM with an average marker interval of 0.6 cM. Fifty-eight previously reported quantitative trait loci (QTL) for 12 traits in these populations were also integrated into the map. In addition, new QTL identified for brix, fructose, glucose and sucrose were added. Some QTL associated with economically important traits detected in different genetic backgrounds mapped to similar genomic regions of the integrated map, suggesting that such QTL are responsible for the phenotypic variability observed in a broad array of watermelon germplasm. Conclusions The integrated map described herein enhances the utility of genomic tools over

  12. Putting diabetes on the map: what does population health really look like at the local level?

    Science.gov (United States)

    Ridgeway, Jennifer L; Lim, Choon-Chern; Liesinger, Juliette T; Smith, Steven A; Shah, Nilay D; Montori, Victor M; Ziegenfuss, Jeanette Y

    2014-01-01

    Population health data are used to profile local conditions, call attention to areas of need, and evaluate health-related programs. Demand for data to inform health care decision making has spurred development of data sources and online systems, but these are often poorly integrated or limited in scope. Our objective was to identify existing data about diabetes mellitus-related conditions in Minnesota, build an online data resource, and identify what data are currently missing that, if available, would better inform assessment of health conditions in the state. A Web site was developed and populated with existing data and data not available elsewhere. It features functionality identified as most important by users, such as maps and county profiles. The site could serve as a flexible tool for stakeholder engagement, but issues were identified during development, including concerns about interpreting map data and open questions about sustainability, that need to be addressed.

  13. Rural population travel time to health services, mapped on Geographic Information System (GIS

    Directory of Open Access Journals (Sweden)

    Ricardo Vicente Ferreira

    2014-04-01

    Full Text Available Distance and travel time are important parameters in the evaluation of access to health services, especially for the population living in the countryside. In the present work, a GIS-based methodology is developed for the mapping of rural road networks and the determination of travel impedances in order to optimize the travel time of the rural population to health care facilities. Data on rural roads classes, slope, sinuosity, visibility and land use are considered in the composition of the impedances synthesis and its application on car travel time. The methodology was applied to the region of Registro (SP, and the results indicate an unequal distribution of health services.

  14. Mapping of the stochastic Lotka-Volterra model to models of population genetics and game theory

    Science.gov (United States)

    Constable, George W. A.; McKane, Alan J.

    2017-08-01

    The relationship between the M -species stochastic Lotka-Volterra competition (SLVC) model and the M -allele Moran model of population genetics is explored via timescale separation arguments. When selection for species is weak and the population size is large but finite, precise conditions are determined for the stochastic dynamics of the SLVC model to be mappable to the neutral Moran model, the Moran model with frequency-independent selection, and the Moran model with frequency-dependent selection (equivalently a game-theoretic formulation of the Moran model). We demonstrate how these mappings can be used to calculate extinction probabilities and the times until a species' extinction in the SLVC model.

  15. Screening for intrinsic water use efficiency in a potato dihaploid mapping population under progressive drought conditions

    DEFF Research Database (Denmark)

    Topbjerg, Henrik Bak; Kaminski, Kacper Piotr; Sørensen, Kirsten Kørup

    2015-01-01

    A drought screening experiment focusing on intrinsic water use efficiency (WUEi) was carried out among 132 clones belonging to a dihaploid potato mapping population. The clones were exposed to progressive soil drying during a five-day period in a greenhouse pot experiment. Analysis...... between leaf ABA concentration and soil water potential was found. The latter findings suggest that the investigated population did not harbour significant genetic variation as to ABA production as function of soil desiccation level or with respect to the sensitivity of stomatal aperture vis-à-vis leaf...... ABA concentration and soil water potential....

  16. A comprehensive population dataset for Afghanistan constructed using GIS-based dasymetric mapping methods

    Science.gov (United States)

    Thompson, Allyson L.; Hubbard, Bernard E.

    2014-01-01

    This report summarizes the application of dasymetric methods for mapping the distribution of population throughout Afghanistan. Because Afghanistan's population has constantly changed through decades of war and conflict, existing vector and raster GIS datasets (such as point settlement densities and intensities of lights at night) do not adequately reflect the changes. The purposes of this report are (1) to provide historic population data at the provincial and district levels that can be used to chart population growth and migration trends within the country and (2) to provide baseline information that can be used for other types of spatial analyses of Afghanistan, such as resource and hazard assessments; infrastructure and capacity rebuilding; and assisting with international, regional, and local planning.

  17. Cross-Population Joint Analysis of eQTLs: Fine Mapping and Functional Annotation

    Science.gov (United States)

    Wen, Xiaoquan; Luca, Francesca; Pique-Regi, Roger

    2015-01-01

    Mapping expression quantitative trait loci (eQTLs) has been shown as a powerful tool to uncover the genetic underpinnings of many complex traits at molecular level. In this paper, we present an integrative analysis approach that leverages eQTL data collected from multiple population groups. In particular, our approach effectively identifies multiple independent cis-eQTL signals that are consistent across populations, accounting for population heterogeneity in allele frequencies and linkage disequilibrium patterns. Furthermore, by integrating genomic annotations, our analysis framework enables high-resolution functional analysis of eQTLs. We applied our statistical approach to analyze the GEUVADIS data consisting of samples from five population groups. From this analysis, we concluded that i) jointly analysis across population groups greatly improves the power of eQTL discovery and the resolution of fine mapping of causal eQTL ii) many genes harbor multiple independent eQTLs in their cis regions iii) genetic variants that disrupt transcription factor binding are significantly enriched in eQTLs (p-value = 4.93 × 10-22). PMID:25906321

  18. Mapping Landscape Friction to Locate Isolated Tsetse Populations that are Candidates for Elimination

    International Nuclear Information System (INIS)

    Bouyer, Jérémy; Dicko, Ahmadou H.; Cecchi, Giuliano; Ravel, Sophie; Solano, Philippe; Guerrini, Laure; Vreysen, Marc J. B.; De Meeûs, Thierry; Lancelot, Renaud

    2016-01-01

    Tsetse flies are the cyclical vectors of deadly human and animal trypanosomes in sub-Saharan Africa. Tsetse control is a key component for the integrated management of both plagues, but local eradication successes have been limited to less than 2% of the infested area. This is attributed to either resurgence of residual populations that were omitted from the eradication campaign or reinvasion from neighboring infested areas. Here we focused on Glossina palpalis gambiensis, a riverine tsetse species representing the main vector of trypanosomoses in West Africa. We mapped landscape resistance to tsetse genetic flow, hereafter referred to as friction, to identify natural barriers that isolate tsetse populations. For this purpose, we fitted a statistical model of the genetic distance between 37 tsetse populations sampled in the region, using a set of remotely sensed environmental data as predictors. The least-cost path between these populations was then estimated using the predicted friction map. The method enabled us to avoid the subjectivity inherent in the expert-based weighting of environmental parameters. Finally, we identified potentially isolated clusters of G. p. gambiensis habitat based on a species distribution model and ranked them according to their predicted genetic distance to the main tsetse population. The methodology presented here will inform the choice on the most appropriate intervention strategies to be implemented against tsetse flies in different parts of Africa. It can also be used to control other pests and to support conservation of endangered species. (author)

  19. Annotated genetic linkage maps of Pinus pinaster Ait. from a Central Spain population using microsatellite and gene based markers

    Directory of Open Access Journals (Sweden)

    de Miguel Marina

    2012-10-01

    Full Text Available Abstract Background Pinus pinaster Ait. is a major resin producing species in Spain. Genetic linkage mapping can facilitate marker-assisted selection (MAS through the identification of Quantitative Trait Loci and selection of allelic variants of interest in breeding populations. In this study, we report annotated genetic linkage maps for two individuals (C14 and C15 belonging to a breeding program aiming to increase resin production. We use different types of DNA markers, including last-generation molecular markers. Results We obtained 13 and 14 linkage groups for C14 and C15 maps, respectively. A total of 211 and 215 markers were positioned on each map and estimated genome length was between 1,870 and 2,166 cM respectively, which represents near 65% of genome coverage. Comparative mapping with previously developed genetic linkage maps for P. pinaster based on about 60 common markers enabled aligning linkage groups to this reference map. The comparison of our annotated linkage maps and linkage maps reporting QTL information revealed 11 annotated SNPs in candidate genes that co-localized with previously reported QTLs for wood properties and water use efficiency. Conclusions This study provides genetic linkage maps from a Spanish population that shows high levels of genetic divergence with French populations from which segregating progenies have been previously mapped. These genetic maps will be of interest to construct a reliable consensus linkage map for the species. The importance of developing functional genetic linkage maps is highlighted, especially when working with breeding populations for its future application in MAS for traits of interest.

  20. Genomic Scans of Zygotic Disequilibrium and Epistatic SNPs in HapMap Phase III Populations.

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    Xin-Sheng Hu

    Full Text Available Previous theory indicates that zygotic linkage disequilibrium (LD is more informative than gametic or composite digenic LD in revealing natural population history. Further, the difference between the composite digenic and maximum zygotic LDs can be used to detect epistatic selection for fitness. Here we corroborate the theory by investigating genome-wide zygotic LDs in HapMap phase III human populations. Results show that non-Africa populations have much more significant zygotic LDs than do Africa populations. Africa populations (ASW, LWK, MKK, and YRI possess more significant zygotic LDs for the double-homozygotes (DAABB than any other significant zygotic LDs (DAABb, DAaBB, and DAaBb, while non-Africa populations generally have more significant DAaBb's than any other significant zygotic LDs (DAABB, DAABb, and DAaBB. Average r-squares for any significant zygotic LDs increase generally in an order of populations YRI, MKK, CEU, CHB, LWK, JPT, CHD, TSI, GIH, ASW, and MEX. Average r-squares are greater for DAABB and DAaBb than for DAaBB and DAABb in each population. YRI and MKK can be separated from LWK and ASW in terms of the pattern of average r-squares. All population divergences in zygotic LDs can be interpreted with the model of Out of Africa for modern human origins. We have also detected 19735-95921 SNP pairs exhibiting strong signals of epistatic selection in different populations. Gene-gene interactions for some epistatic SNP pairs are evident from empirical findings, but many more epistatic SNP pairs await evidence. Common epistatic SNP pairs rarely exist among all populations, but exist in distinct regions (Africa, Europe, and East Asia, which helps to understand geographical genomic medicine.

  1. Studies on maize inbred lines susceptibility to herbicides

    Directory of Open Access Journals (Sweden)

    Stefanović Lidija

    2010-01-01

    Full Text Available This paper presents the analysis of results obtained during long- term studies on the response of maize inbred lines to herbicides. Under the agroecological conditions of Zemun Polje the response (reaction of maize inbred lines to herbicides of different classes was investigated. Biological tests were performed and some agronomic, morphological, physiological and biochemical parameters were determined when the response of maize inbred lines to herbicides was estimated. The use of active ingredients of herbicides from triazine, acetanilide, thiocarbamate to new chemical groups (sulfonylurea etc., have been resulted in changes in weed suppression and susceptibility of inbred lines. Obtained results show that effects of herbicides on susceptible maize genotypes can be different: they can slowdown the growth and development and affect the plant height; they can also affect the stages of the tassel and ear development and at the end they can reduced grain yield of the tested inbreds. Numerous studies confirmed the existence of differences in susceptibility level of maize genotypes in relation to herbicides. According to gained results the recommendations for growers are made on the possibility of the application of new herbicides in the hybrid seed production.

  2. A high-resolution CNV map across Brown Swiss cattle populations.

    Directory of Open Access Journals (Sweden)

    Raphaëlle Teresa Matilde Maria Prinsen

    2015-07-01

    Full Text Available Genomic studies and their use in selection programs are having a strong impact in dairy cattle selection (E. Liu et al., 2010. The first aim was to create a high resolution map of CNV regions (CNVRs in Brown Swiss cattle and the characterization of identified CNVs as markers for quantitative and population genetic studies. CNVs were called in a set of 164 sires with PennCNV and genoCN. PennCNV identified 2,377 CNVRs comprising 1,162 and 1,131 gain and loss events, respectively, and 84 regions of complex nature. GenoCN detected 41,519 CNVRs comprising 3,475 and 34,485 gain and loss events, respectively, and 3,559 regions of complex ones. Consensus calls between algorithms were summarized to CNVRs at the population level. GenoCN was also used to identify total allelic content in consensus CNVRs. Moreover, population haplotype frequencies were calculated. Linkage disequilibrium (LD was established between CNVs and SNPs in and around CNVRs. In this study the potential contribution of CNVs as genetic markers for genome wide association studies (GWAS has been assessed thanks to PIC and LD values. The next aim is to investigate genomic structural variation in cattle using dense SNP information in more than 1000 samples of the Italian and Swiss Brown Swiss breed genotyped on HD Bovine BeadChips. Today there is still no CNV map available across Brown Swiss populations belonging to different countries. This study therefore expands the catalogue of CNVRs in the bovine genome, delivers an international based high-resolution map of CNVRs specific to Brown Swiss dairy cattle and will lastly provide information for GEBV estimation with CNVs.

  3. Genomewide Linkage Disequilibrium Mapping of Severe Bipolar Disorder in a Population Isolate

    Science.gov (United States)

    Ophoff, Roel A.; Escamilla, Michael A.; Service, Susan K.; Spesny, Mitzi; Meshi, Dar B.; Poon, Wingman; Molina, Julio; Fournier, Eduardo; Gallegos, Alvaro; Mathews, Carol; Neylan, Thomas; Batki, Steven L.; Roche, Erin; Ramirez, Margarita; Silva, Sandra; De Mille, Melissa C.; Dong, Penny; Leon, Pedro E.; Reus, Victor I.; Sandkuijl, Lodewijk A.; Freimer, Nelson B.

    2002-01-01

    Genomewide association studies may offer the best promise for genetic mapping of complex traits. Such studies in outbred populations require very densely spaced single-nucleotide polymorphisms. In recently founded population isolates, however, extensive linkage disequilibrium (LD) may make these studies feasible with currently available sets of short tandem repeat markers, spaced at intervals as large as a few centimorgans. We report the results of a genomewide association study of severe bipolar disorder (BP-I), using patients from the isolated population of the central valley of Costa Rica. We observed LD with BP-I on several chromosomes; the most striking results were in proximal 8p, a region that has previously shown linkage to schizophrenia. This region could be important for severe psychiatric disorders, rather than for a specific phenotype. PMID:12119601

  4. Estimating population size of a nocturnal burrow-nesting seabird using acoustic monitoring and habitat mapping

    Directory of Open Access Journals (Sweden)

    Steffen Oppel

    2014-04-01

    Full Text Available Population size assessments for nocturnal burrow-nesting seabirds are logistically challenging because these species are active in colonies only during darkness and often nest on remote islands where manual inspections of breeding burrows are not feasible. Many seabird species are highly vocal, and recent technological innovations now make it possible to record and quantify vocal activity in seabird colonies. Here we test the hypothesis that remotely recorded vocal activity in Cory’s shearwater (Calonectris borealis breeding colonies in the North Atlantic increases with nest density, and combined this relationship with cliff habitat mapping to estimate the population size of Cory’s shearwaters on the island of Corvo (Azores. We deployed acoustic recording devices in 9 Cory’s shearwater colonies of known size to establish a relationship between vocal activity and local nest density (slope = 1.07, R2 = 0.86, p < 0.001. We used this relationship to predict the nest density in various cliff habitat types and produced a habitat map of breeding cliffs to extrapolate nest density around the island of Corvo. The mean predicted nest density on Corvo ranged from 6.6 (2.1–16.2 to 27.8 (19.5–36.4 nests/ha. Extrapolation of habitat-specific nest densities across the cliff area of Corvo resulted in an estimate of 6326 Cory’s shearwater nests (95% confidence interval: 3735–10,524. This population size estimate is similar to previous assessments, but is too imprecise to detect moderate changes in population size over time. While estimating absolute population size from acoustic recordings may not be sufficiently precise, the strong positive relationship that we found between local nest density and recorded calling rate indicates that passive acoustic monitoring may be useful to document relative changes in seabird populations over time.

  5. Confirmation and Fine Mapping of a Major QTL for Aflatoxin Resistance in Maize Using a Combination of Linkage and Association Mapping

    Directory of Open Access Journals (Sweden)

    Yu Zhang

    2016-09-01

    Full Text Available Maize grain contamination with aflatoxin from Aspergillus flavus (A. flavus is a serious health hazard to animals and humans. To map the quantitative trait loci (QTLs associated with resistance to A. flavus, we employed a powerful approach that differs from previous methods in one important way: it combines the advantages of the genome-wide association analysis (GWAS and traditional linkage mapping analysis. Linkage mapping was performed using 228 recombinant inbred lines (RILs, and a highly significant QTL that affected aflatoxin accumulation, qAA8, was mapped. This QTL spanned approximately 7 centi-Morgan (cM on chromosome 8. The confidence interval was too large for positional cloning of the causal gene. To refine this QTL, GWAS was performed with 558,629 single nucleotide polymorphisms (SNPs in an association population comprising 437 maize inbred lines. Twenty-five significantly associated SNPs were identified, most of which co-localised with qAA8 and explained 6.7% to 26.8% of the phenotypic variation observed. Based on the rapid linkage disequilibrium (LD and the high density of SNPs in the association population, qAA8 was further localised to a smaller genomic region of approximately 1500 bp. A high-resolution map of the qAA8 region will be useful towards a marker-assisted selection (MAS of A. flavus resistance and a characterisation of the causal gene.

  6. Are designer guppies inbred? Microsatellite variation in five strains of ornamental guppies, Poecilia reticulata, used for behavioral research.

    Science.gov (United States)

    Bleakley, Bronwyn H; Eklund, Amy C; Brodie, Edmund D

    2008-01-01

    Inbred lines are an important tool of genetic studies of all traits, including behavior. Independently derived strains of ornamental "designer" guppies are readily available and predicted to be inbred; however, little is known about actual levels of inbreeding in any of these strains or whether these lines differ in genetic traits that have not been under strong directional artificial selection. We genotyped five designer strains of guppies known to vary in their responses to predator cues and a wild reference population to determine whether designer strains show evidence of inbreeding and whether the strains differed from each other at five microsatellite loci. The designer strains exhibited lower allelic diversity and observed heterozygosity than the wild population. Observed heterozygosity departed significantly from expected heterozygosity for most markers in all five strains of designer guppies. Inbreeding coefficient (f) comparisons between the wild reference population and the designer strains show considerable inbreeding in the designer strains. F(is) values for the designer strains also provide evidence of inbreeding. Finally, F(st) values indicate that the designer strains differ significantly from each other and the wild population. We therefore concluded that designer guppies are inbred compared to wild populations and differ among strains, making them useful tools for genetic studies of behavioral or life history traits.

  7. Identification and evaluation of resistance to powdery mildew and yellow rust in a wheat mapping population

    Science.gov (United States)

    Zhang, Xu; Wang, Jirui; Luo, Mingcheng; Yang, Mujun; Wang, Hua; Xiang, Libo; Zeng, Fansong; Yu, Dazhao; Fu, Daolin

    2017-01-01

    Deployment of cultivars with genetic resistance is an effective approach to control the diseases of powdery mildew (PM) and yellow rust (YR). Chinese wheat cultivar XK0106 exhibits high levels of resistance to both diseases, while cultivar E07901 has partial, adult plant resistance (APR). The aim of this study was to map resistance loci derived from the two cultivars and analyze their effects against PM and YR in a range of environments. A doubled haploid population (388 lines) was used to develop a framework map consisting of 117 SSR markers, while a much higher density map using the 90K Illumina iSelect SNP array was produced with a subset of 80 randomly selected lines. Seedling resistance was characterized against a range of PM and YR isolates, while field scores in multiple environments were used to characterize APR. Composite interval mapping (CIM) of seedling PM scores identified two QTLs (QPm.haas-6A and QPm.haas-2A), the former being located at the Pm21 locus. These QTLs were also significant in field scores, as were Qpm.haas-3A and QPm.haas-5A. QYr.haas-1B-1 and QYr.haas-2A were identified in field scores of YR and were located at the Yr24/26 and Yr17 chromosomal regions respectively. A second 1B QTL, QYr.haas-1B-2 was also identified. QPm.haas-2A and QYr.haas-1B-2 are likely to be new QTLs that have not been previously identified. Effects of the QTLs were further investigated in multiple environments through the testing of selected lines predicted to contain various QTL combinations. Significant additive interactions between the PM QTLs highlighted the ability to pyramid these loci to provide higher level of resistance. Interactions between the YR QTLs gave insights into the pathogen populations in the different locations as well as showing genetic interactions between these loci. PMID:28542459

  8. Identification and evaluation of resistance to powdery mildew and yellow rust in a wheat mapping population.

    Directory of Open Access Journals (Sweden)

    Lijun Yang

    Full Text Available Deployment of cultivars with genetic resistance is an effective approach to control the diseases of powdery mildew (PM and yellow rust (YR. Chinese wheat cultivar XK0106 exhibits high levels of resistance to both diseases, while cultivar E07901 has partial, adult plant resistance (APR. The aim of this study was to map resistance loci derived from the two cultivars and analyze their effects against PM and YR in a range of environments. A doubled haploid population (388 lines was used to develop a framework map consisting of 117 SSR markers, while a much higher density map using the 90K Illumina iSelect SNP array was produced with a subset of 80 randomly selected lines. Seedling resistance was characterized against a range of PM and YR isolates, while field scores in multiple environments were used to characterize APR. Composite interval mapping (CIM of seedling PM scores identified two QTLs (QPm.haas-6A and QPm.haas-2A, the former being located at the Pm21 locus. These QTLs were also significant in field scores, as were Qpm.haas-3A and QPm.haas-5A. QYr.haas-1B-1 and QYr.haas-2A were identified in field scores of YR and were located at the Yr24/26 and Yr17 chromosomal regions respectively. A second 1B QTL, QYr.haas-1B-2 was also identified. QPm.haas-2A and QYr.haas-1B-2 are likely to be new QTLs that have not been previously identified. Effects of the QTLs were further investigated in multiple environments through the testing of selected lines predicted to contain various QTL combinations. Significant additive interactions between the PM QTLs highlighted the ability to pyramid these loci to provide higher level of resistance. Interactions between the YR QTLs gave insights into the pathogen populations in the different locations as well as showing genetic interactions between these loci.

  9. The SAURON project : XVII. Stellar population analysis of the absorption line strength maps of 48 early-type galaxies

    NARCIS (Netherlands)

    Kuntschner, Harald; Emsellem, Eric; Bacon, Roland; Cappellari, Michele; Davies, Roger L.; de Zeeuw, P. Tim; Falcon-Barroso, Jesus; Krajnovic, Davor; McDermid, Richard M.; Peletier, Reynier F.; Sarzi, Marc; Shapiro, Kristen L.; van den Bosch, Remco C. E.; van de Ven, Glenn; Krajnović, Davor

    2010-01-01

    We present a stellar population analysis of the absorption line strength maps for 48 early-type galaxies from the SAURON sample. Using the line strength index maps of H beta, Fe5015 and Mgb, measured in the Lick/IDS system and spatially binned to a constant signal-to-noise ratio, together with

  10. The SAURON project - XVII. Stellar population analysis of the absorption line strength maps of 48 early-type galaxies

    NARCIS (Netherlands)

    Kuntschner, Harald; Emsellem, Eric; Bacon, Roland; Cappellari, Michele; Davies, Roger L.; de Zeeuw, P. Tim; Falcón-Barroso, Jesús; Krajnović, Davor; McDermid, Richard M.; Peletier, Reynier F.; Sarzi, Marc; Shapiro, Kristen L.; van den Bosch, Remco C. E.; van de Ven, Glenn

    2010-01-01

    We present a stellar population analysis of the absorption line strength maps for 48 early-type galaxies from the SAURON sample. Using the line strength index maps of Hβ, Fe5015 and Mgb, measured in the Lick/IDS system and spatially binned to a constant signal-to-noise ratio, together with

  11. Evaluation of Hbr (MITE) markers for assessment of genetic relationships among maize ( Zea mays L.) inbred lines.

    Science.gov (United States)

    Casa, A M; Mitchell, S E; Smith, O S; Register, J C; Wessler, S R; Kresovich, S

    2002-01-01

    Recently, a new type of molecular marker has been developed that is based on the presence or absence of the miniature inverted repeat transposable element (MITE) family Heartbreaker ( Hbr) in the maize genome. These so-called Hbr markers have been shown to be stable, highly polymorphic, easily mapped, and evenly distributed throughout the maize genome. In this work, we used Hbr-derived markers for genetic characterization of a set of maize inbred lines belonging to Stiff Stalk (SS) and Non-Stiff Stalk (NSS) heterotic groups. In total, 111 markers were evaluated across 62 SS and NSS lines. Seventy six markers (68%) were shared between the two groups, and 25 of the common markers occurred at fairly low frequency (Hbr data were congruent with those derived from pedigree information). Distance matrices generated from Hbr markers were significantly correlated ( pHbr markers could be used in conjunction with other molecular markers for genotyping and relationship studies of related maize inbred lines.

  12. IDENTIFICATION OF A MAJOR QUANTITATIVE TRAIT LOCUS CONFERRING RICE BLAST RESISTANCE USING RECOMBINANT INBRED LINES

    Directory of Open Access Journals (Sweden)

    Sobrizal Sobrizal

    2013-05-01

    Full Text Available Blast disease caused by Pyricularia oryzae is one of the limiting factors for rice production world wide. The use of resistant varieties for managing blast disease is considered as the most eco-friendly approaches. However, their resistances may be broken down within a few years due to the appearance of new virulent blast races in the field. The objective of the present study was to identify the quantitative trait locus (QTL conferring resistance to blast disease using 126 recombinant inbred (RI lines originated from a crossing of a durably resistant upland rice genotype (Laka and a highly susceptible rice accession cultivar (Kencana Bali. The RI population was developed through a single seed descent method from 1997 to 2004. Resistance of the RI lines was evaluated for blast in an endemic area of Sukabumi, West Java, in 2005. Disease intensity of the blast was examined following the standard evaluation system developed by the International Rice Research Institute (IRRI. At the same year the RI lines were analyzed with 134 DNA markers. Results of the study showed that one major QTL was found to be associated with blast resistance, and this QTL was located near RM2136 marker on the long arm of chromosome 11. This QTL explained 87% of the phenotypic variation with 37% additive effect. The map position of this QTL differed from that of a partial resistant gene, Pi34, identified previously on chromosome 11 in the Japanese durably resistant variety, Chubu 32. The QTL, however, was almost at the same position as that of the multiple allele-resistant gene, Pik. Therefore, an allelic test should be conducted to clarify the allelic relationship between QTL identified in this study and the Pik. The RI lines are the permanent segregating population that could be very useful for analysing phenotypic variations of important agronomic traits possibly owned by the RI lines. The major QTL identified in this study could be used as a genetic resource in

  13. Reconstructions of human history by mapping dental markers in living Eurasian populations

    Science.gov (United States)

    Kashibadze, Vera F.; Nasonova, Olga G.; Nasonov, Dmitry S.

    2013-01-01

    Using advances in gene geography and anthropophenetics, the phenogeographical method for anthropological research was initiated and developed using dental data. Statistical and cartographical analyses are provided for 498 living Eurasian populations. Mapping principal components supplied evidence for the phene pool structure in Eurasian populations, and for reconstructions of Homo sapiens history on the continent. Longitudinal variability seems to be the most important regularity revealed by principal components analysis (PCA) and mapping, indicating the division of the whole area into western and eastern main provinces. So, the most ancient scenario in the history of Eurasian populations developed from two perspective different groups: a western group related to ancient populations of West Asia and an eastern one rooted in ancestry in South and/or East Asia. In spite of the enormous territory and the revealed divergence, the populations of the continent have undergone wide scale and intensive timeespace interaction. Many details in the revealed landscapes are background to different historical events. Migrations and assimilation are two essential phenomena in Eurasian history: the widespread of the western combination through the whole continent to the Pacific coastline and the movement of the paradoxical combinations of eastern and western markers from South or Central Asia to the east and west. Taking into account that no additional eastern combinations in the total variation in Asian groups have been found, but that mixed or western markers' sets and that eastern dental characteristics are traced in Asia since Homo erectus, the assumption is made in favour of the hetero-level assimilation in the eastern province and of net-like evolution of H. sapiens.

  14. Genetic variation between Spanish and American versions of sweet corn inbred lines

    OpenAIRE

    Revilla Temiño, Pedro; Abuín, María del Carmen; Malvar Pintos, Rosa Ana; Soengas Fernández, María del Pilar; Ordás López, Bernardo; Ordás Pérez, Amando

    2005-01-01

    Conservation of maize inbred lines in different stations causes variability among strains. The objective of this research was to determine agronomic and molecular differences in American sweet corn inbreds maintained in Spain. American and Spanish strains of five sweet corn inbred lines were characterized by using 34 RAPD primers that produced 168 consistent bands. Strains of four of these inbreds were crossed in a diallel design, and hybrids were evaluated in four environments in northwester...

  15. Exploring potential of pearl millet germplasm association panel for association mapping of drought tolerance traits.

    Directory of Open Access Journals (Sweden)

    Deepmala Sehgal

    Full Text Available A pearl millet inbred germplasm association panel (PMiGAP comprising 250 inbred lines, representative of cultivated germplasm from Africa and Asia, elite improved open-pollinated cultivars, hybrid parental inbreds and inbred mapping population parents, was recently established. This study presents the first report of genetic diversity in PMiGAP and its exploitation for association mapping of drought tolerance traits. For diversity and genetic structure analysis, PMiGAP was genotyped with 37 SSR and CISP markers representing all seven linkage groups. For association analysis, it was phenotyped for yield and yield components and morpho-physiological traits under both well-watered and drought conditions, and genotyped with SNPs and InDels from seventeen genes underlying a major validated drought tolerance (DT QTL. The average gene diversity in PMiGAP was 0.54. The STRUCTURE analysis revealed six subpopulations within PMiGAP. Significant associations were obtained for 22 SNPs and 3 InDels from 13 genes under different treatments. Seven SNPs associations from 5 genes were common under irrigated and one of the drought stress treatments. Most significantly, an important SNP in putative acetyl CoA carboxylase gene showed constitutive association with grain yield, grain harvest index and panicle yield under all treatments. An InDel in putative chlorophyll a/b binding protein gene was significantly associated with both stay-green and grain yield traits under drought stress. This can be used as a functional marker for selecting high yielding genotypes with 'stay green' phenotype under drought stress. The present study identified useful marker-trait associations of important agronomics traits under irrigated and drought stress conditions with genes underlying a major validated DT-QTL in pearl millet. Results suggest that PMiGAP is a useful panel for association mapping. Expression patterns of genes also shed light on some physiological mechanisms underlying

  16. Mapping of the stochastic Lotka-Volterra model to models of population genetics and game theory.

    Science.gov (United States)

    Constable, George W A; McKane, Alan J

    2017-08-01

    The relationship between the M-species stochastic Lotka-Volterra competition (SLVC) model and the M-allele Moran model of population genetics is explored via timescale separation arguments. When selection for species is weak and the population size is large but finite, precise conditions are determined for the stochastic dynamics of the SLVC model to be mappable to the neutral Moran model, the Moran model with frequency-independent selection, and the Moran model with frequency-dependent selection (equivalently a game-theoretic formulation of the Moran model). We demonstrate how these mappings can be used to calculate extinction probabilities and the times until a species' extinction in the SLVC model.

  17. Consumption Characteristics Mapping of the Base of the Pyramid (BOP Population in Brazil

    Directory of Open Access Journals (Sweden)

    Renata Giovinazzo Spers

    2015-11-01

    Full Text Available The objective of this study is to outline a diagnosis of the BoP's population in Brazil, regarding their size and consumption characteristics. This is a relevant and current issue, considering that BoP needs to be understood as a large potential market with its own logic, also representing a large productive potential, which, if well developed, will bring very positive impacts to these communities. To achieve this, a theoretical survey was made. After, search was made based on secondary data about Brazilian BoP population participation and a mapping of their consumption profile, identifying main categories of goods consumed. This research generated meaningful results for society, companies and the Academy, hopefully consolidating a relevant line of research and management education.

  18. Generalization and fine mapping of European ancestry-based central adiposity variants in African ancestry populations.

    Science.gov (United States)

    Yoneyama, S; Yao, J; Guo, X; Fernandez-Rhodes, L; Lim, U; Boston, J; Buzková, P; Carlson, C S; Cheng, I; Cochran, B; Cooper, R; Ehret, G; Fornage, M; Gong, J; Gross, M; Gu, C C; Haessler, J; Haiman, C A; Henderson, B; Hindorff, L A; Houston, D; Irvin, M R; Jackson, R; Kuller, L; Leppert, M; Lewis, C E; Li, R; Le Marchand, L; Matise, T C; Nguyen, K-Dh; Chakravarti, A; Pankow, J S; Pankratz, N; Pooler, L; Ritchie, M D; Bien, S A; Wassel, C L; Chen, Y-D I; Taylor, K D; Allison, M; Rotter, J I; Schreiner, P J; Schumacher, F; Wilkens, L; Boerwinkle, E; Kooperberg, C; Peters, U; Buyske, S; Graff, M; North, K E

    2017-02-01

    Central adiposity measures such as waist circumference (WC) and waist-to-hip ratio (WHR) are associated with cardiometabolic disorders independently of body mass index (BMI) and are gaining clinically utility. Several studies report genetic variants associated with central adiposity, but most utilize only European ancestry populations. Understanding whether the genetic associations discovered among mainly European descendants are shared with African ancestry populations will help elucidate the biological underpinnings of abdominal fat deposition. To identify the underlying functional genetic determinants of body fat distribution, we conducted an array-wide association meta-analysis among persons of African ancestry across seven studies/consortia participating in the Population Architecture using Genomics and Epidemiology (PAGE) consortium. We used the Metabochip array, designed for fine-mapping cardiovascular-associated loci, to explore novel array-wide associations with WC and WHR among 15 945 African descendants using all and sex-stratified groups. We further interrogated 17 known WHR regions for African ancestry-specific variants. Of the 17 WHR loci, eight single-nucleotide polymorphisms (SNPs) located in four loci were replicated in the sex-combined or sex-stratified meta-analyses. Two of these eight independently associated with WHR after conditioning on the known variant in European descendants (rs12096179 in TBX15-WARS2 and rs2059092 in ADAMTS9). In the fine-mapping assessment, the putative functional region was reduced across all four loci but to varying degrees (average 40% drop in number of putative SNPs and 20% drop in genomic region). Similar to previous studies, the significant SNPs in the female-stratified analysis were stronger than the significant SNPs from the sex-combined analysis. No novel associations were detected in the array-wide analyses. Of 17 previously identified loci, four loci replicated in the African ancestry populations of this

  19. Combing Ability Analysis ofamong Early Generation Maize Inbred ...

    African Journals Online (AJOL)

    dagne.cimdom

    estimate combining ability effects of locally developed and introduced early generation maize inbred lines for grain ... variance revealed significant difference among the hybrids for all studied traits. General ... Guto LMS5, L15 x SC22 and L20 x TSC22) gave significantly higher grain yield advantage over the two standard ...

  20. Regeneration of Sudanese maize inbred lines and open pollinated ...

    African Journals Online (AJOL)

    Eight maize inbred lines and three open pollinated varieties from Sudan were evaluated for their response to tissue culture. Immature embryos obtained 16 days after pollination were used as explants for callus induction. Calli were induced on LS medium supplemented with 2 mg/L 2,4-dichlorophenoxyacetic acid.

  1. determination of the heterotic groups of maize inbred lines

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    Maize weevil (Sitophilus zeamais Motschulsky) is a major maize (Zea mays L) storage insect pest in the tropics. Fifty-two inbred lines developed for weevil resistance were crossed to two testers, A and B, to determine their heterotic groups and inheritance of resistance to maize weevil. For 10 testcrosses selected for ...

  2. Haldane, Waddington and recombinant inbred lines: extension of ...

    Indian Academy of Sciences (India)

    In the early 1930s, J. B. S. Haldane and C. H. Waddington collaborated on the consequences of genetic linkage and inbreeding. One elegant mathematical genetics problem solved by them concerns recombinant inbred lines (RILs) produced via repeated self or brother–sister mating. In this classic contribution, Haldane ...

  3. Biplot analysis of diallel crosses of NS maize inbred lines

    NARCIS (Netherlands)

    Bocanski, J.; Nastasic, A.; Stanisavljevic, D.; Sreckov, Z.; Mitrovic, B.; Treskic, S.; Vukosavljev, M.

    2011-01-01

    Bocanski J., A. Nastasic, D. Stanisavljevic, Z. Sreckov, B. Mitrovic, S. Treskic and M. Vukosavljev (2011): Biplot analysis of diallel crosses of NS maize inbred lines- Genetika, Vol 43, No. 2, 277 - 284. Genetic markers, from morphological to molecular, in function with early Heterosis is a

  4. Screening of recombinant inbred lines for salinity tolerance in bread ...

    African Journals Online (AJOL)

    Screening a large number of plants for salinity tolerance is not easy, therefore this investigation was performed to evaluate and screen 186 F8 recombinant inbred lines (RILs) derived from a cross between Superhead#2 (Super Seri) and Roshan wheat varieties for salinity tolerance. All the individuals were evaluated under ...

  5. Regeneration of Sudanese maize inbred lines and open pollinated ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-03

    Jun 3, 2008 ... Eight maize inbred lines and three open pollinated varieties from Sudan were evaluated for their response to tissue ... Keywords: Sudanese maize genotypes, embryogenic callus, regeneration, and tissue culture. INTRODUCTION .... genes have been implicated in the inheritance of callus induction and ...

  6. Assessment of genetic variability of maize inbred lines and their ...

    African Journals Online (AJOL)

    Assessment of genetic variability of maize inbred lines and their hybrids under normal and drought conditions. ... Nigeria Agricultural Journal ... Analysis of variance revealed significant differences for most of the characters under study which indicates the presence of sufficient amount of variability offering ample scope for ...

  7. Accounting for Errors in Low Coverage High-Throughput Sequencing Data When Constructing Genetic Maps Using Biparental Outcrossed Populations.

    Science.gov (United States)

    Bilton, Timothy P; Schofield, Matthew R; Black, Michael A; Chagné, David; Wilcox, Phillip L; Dodds, Ken G

    2018-02-27

    Next generation sequencing is an efficient method that allows for substantially more markers than previous technologies, providing opportunities for building high density genetic linkage maps, which facilitate the development of non-model species' genomic assemblies and the investigation of their genes. However, constructing genetic maps using data generated via high-throughput sequencing technology (e.g., genotyping-by-sequencing) is complicated by the presence of sequencing errors and genotyping errors resulting from missing parental alleles due to low sequencing depth. If unaccounted for, these errors lead to inflated genetic maps. In addition, map construction in many species is performed using full-sib family populations derived from the outcrossing of two individuals, where unknown parental phase and varying segregation types further complicate construction. We present a new methodology for modeling low coverage sequencing data in the construction of genetic linkage maps using full-sib populations of diploid species, implemented in a package called GUSMap. Our model is based on an extension of the Lander-Green hidden Markov model that accounts for errors present in sequencing data. Results show that GUSMap was able to give accurate estimates of the recombination fractions and overall map distance, while most existing mapping packages produced inflated genetic maps in the presence of errors. Our results demonstrate the feasibility of using low coverage sequencing data to produce genetic maps without requiring extensive filtering of potentially erroneous genotypes, provided that the associated errors are correctly accounted for in the model. Copyright © 2018, Genetics.

  8. Spatially associated clump populations in Rosette from CO and dust maps

    Science.gov (United States)

    Veltchev, Todor V.; Ossenkopf-Okada, Volker; Stanchev, Orlin; Schneider, Nicola; Donkov, Sava; Klessen, Ralf S.

    2018-04-01

    Spatial association of clumps from different tracers turns out to be a valuable tool to determine the physical properties of molecular clouds. It provides a reliable estimate for the X-factors, serves to trace the density of clumps seen in column densities only, and allows one to measure the velocity dispersion of clumps identified in dust emission. We study the spatial association between clump populations, extracted by use of the GAUSSCLUMPS technique from 12CO (1-0), 13CO (1-0) line maps and Herschel dust-emission maps of the star-forming region Rosette, and analyse their physical properties. All CO clumps that overlap with another CO or dust counterpart are found to be gravitationally bound and located in the massive star-forming filaments of the molecular cloud. They obey a single mass-size relation M_cl∝ R_cl^γ with γ ≃ 3 (implying constant mean density) and display virtually no velocity-size relation. We interpret their population as low-density structures formed through compression by converging flows and still not evolved under the influence of self-gravity. The high-mass parts of their clump mass functions are fitted by a power law dN_cl/d log M_cl∝ M_cl^{Γ } and display a nearly Salpeter slope Γ ˜ -1.3. On the other hand, clumps extracted from the dust-emission map exhibit a shallower mass-size relation with γ = 2.5 and mass functions with very steep slopes Γ ˜ -2.3 even if associated with CO clumps. They trace density peaks of the associated CO clumps at scales of a few tenths of pc where no single density scaling law should be expected.

  9. Development of an ultra-dense genetic map of the sunflower genome based on single-feature polymorphisms.

    Directory of Open Access Journals (Sweden)

    John E Bowers

    Full Text Available The development of ultra-dense genetic maps has the potential to facilitate detailed comparative genomic analyses and whole genome sequence assemblies. Here we describe the use of a custom Affymetrix GeneChip containing nearly 2.4 million features (25 bp sequences targeting 86,023 unigenes from sunflower (Helianthus annuus L. and related species to test for single-feature polymorphisms (SFPs in a recombinant inbred line (RIL mapping population derived from a cross between confectionery and oilseed sunflower lines (RHA280×RHA801. We then employed an existing genetic map derived from this same population to rigorously filter out low quality data and place 67,486 features corresponding to 22,481 unigenes on the sunflower genetic map. The resulting map contains a substantial fraction of all sunflower genes and will thus facilitate a number of downstream applications, including genome assembly and the identification of candidate genes underlying QTL or traits of interest.

  10. Association Mapping of Biomass Yield and Stem Composition in a Tetraploid Alfalfa Breeding Population

    Directory of Open Access Journals (Sweden)

    Xuehui Li

    2011-03-01

    Full Text Available Alfalfa ( L., an important forage crop that is also a potential biofuel crop, has advantages of high yield, high lignocellulose concentration in stems, and has low input costs. In this study, we investigated population structure and linkage disequilibrium (LD patterns in a tetraploid alfalfa breeding population using genome-wide simple sequence repeat (SSR markers and identified markers related to yield and cell wall composition by association mapping. No obvious population structure was found in our alfalfa breeding population, which could be due to the relatively narrow genetic base of the founders and/or due to two generations of random mating. We found significant LD ( 10% alleles across the 71 SSR markers, 15 showed strong association ( < 0.005 with yield in at least one of five environments, and most of the 15 alleles were identified in multiple environments. Only one allele showed strong association with acid detergent fiber (ADF and one allele with acid detergent lignin (ADL. Alleles associated with traits could be directly applied in a breeding program using marker-assisted selection. However, based on our estimated LD level, we would need about 1000 markers to explore the whole alfalfa genome for association between markers and traits.

  11. Mapping populations at risk: improving spatial demographic data for infectious disease modeling and metric derivation

    Directory of Open Access Journals (Sweden)

    Tatem Andrew J

    2012-05-01

    Full Text Available Abstract The use of Global Positioning Systems (GPS and Geographical Information Systems (GIS in disease surveys and reporting is becoming increasingly routine, enabling a better understanding of spatial epidemiology and the improvement of surveillance and control strategies. In turn, the greater availability of spatially referenced epidemiological data is driving the rapid expansion of disease mapping and spatial modeling methods, which are becoming increasingly detailed and sophisticated, with rigorous handling of uncertainties. This expansion has, however, not been matched by advancements in the development of spatial datasets of human population distribution that accompany disease maps or spatial models. Where risks are heterogeneous across population groups or space or dependent on transmission between individuals, spatial data on human population distributions and demographic structures are required to estimate infectious disease risks, burdens, and dynamics. The disease impact in terms of morbidity, mortality, and speed of spread varies substantially with demographic profiles, so that identifying the most exposed or affected populations becomes a key aspect of planning and targeting interventions. Subnational breakdowns of population counts by age and sex are routinely collected during national censuses and maintained in finer detail within microcensus data. Moreover, demographic and health surveys continue to collect representative and contemporary samples from clusters of communities in low-income countries where census data may be less detailed and not collected regularly. Together, these freely available datasets form a rich resource for quantifying and understanding the spatial variations in the sizes and distributions of those most at risk of disease in low income regions, yet at present, they remain unconnected data scattered across national statistical offices and websites. In this paper we discuss the deficiencies of existing

  12. Mapping populations at risk: improving spatial demographic data for infectious disease modeling and metric derivation.

    Science.gov (United States)

    Tatem, Andrew J; Adamo, Susana; Bharti, Nita; Burgert, Clara R; Castro, Marcia; Dorelien, Audrey; Fink, Gunter; Linard, Catherine; John, Mendelsohn; Montana, Livia; Montgomery, Mark R; Nelson, Andrew; Noor, Abdisalan M; Pindolia, Deepa; Yetman, Greg; Balk, Deborah

    2012-05-16

    The use of Global Positioning Systems (GPS) and Geographical Information Systems (GIS) in disease surveys and reporting is becoming increasingly routine, enabling a better understanding of spatial epidemiology and the improvement of surveillance and control strategies. In turn, the greater availability of spatially referenced epidemiological data is driving the rapid expansion of disease mapping and spatial modeling methods, which are becoming increasingly detailed and sophisticated, with rigorous handling of uncertainties. This expansion has, however, not been matched by advancements in the development of spatial datasets of human population distribution that accompany disease maps or spatial models.Where risks are heterogeneous across population groups or space or dependent on transmission between individuals, spatial data on human population distributions and demographic structures are required to estimate infectious disease risks, burdens, and dynamics. The disease impact in terms of morbidity, mortality, and speed of spread varies substantially with demographic profiles, so that identifying the most exposed or affected populations becomes a key aspect of planning and targeting interventions. Subnational breakdowns of population counts by age and sex are routinely collected during national censuses and maintained in finer detail within microcensus data. Moreover, demographic and health surveys continue to collect representative and contemporary samples from clusters of communities in low-income countries where census data may be less detailed and not collected regularly. Together, these freely available datasets form a rich resource for quantifying and understanding the spatial variations in the sizes and distributions of those most at risk of disease in low income regions, yet at present, they remain unconnected data scattered across national statistical offices and websites.In this paper we discuss the deficiencies of existing spatial population datasets and

  13. Fine mapping of the Bsr1 barley stripe mosaic virus resistance gene in the model grass Brachypodium distachyon.

    Directory of Open Access Journals (Sweden)

    Yu Cui

    Full Text Available The ND18 strain of Barley stripe mosaic virus (BSMV infects several lines of Brachypodium distachyon, a recently developed model system for genomics research in cereals. Among the inbred lines tested, Bd3-1 is highly resistant at 20 to 25 °C, whereas Bd21 is susceptible and infection results in an intense mosaic phenotype accompanied by high levels of replicating virus. We generated an F(6:7 recombinant inbred line (RIL population from a cross between Bd3-1 and Bd21 and used the RILs, and an F(2 population of a second Bd21 × Bd3-1 cross to evaluate the inheritance of resistance. The results indicate that resistance segregates as expected for a single dominant gene, which we have designated Barley stripe mosaic virus resistance 1 (Bsr1. We constructed a genetic linkage map of the RIL population using SNP markers to map this gene to within 705 Kb of the distal end of the top of chromosome 3. Additional CAPS and Indel markers were used to fine map Bsr1 to a 23 Kb interval containing five putative genes. Our study demonstrates the power of using RILs to rapidly map the genetic determinants of BSMV resistance in Brachypodium. Moreover, the RILs and their associated genetic map, when combined with the complete genomic sequence of Brachypodium, provide new resources for genetic analyses of many other traits.

  14. Mitochondrial DNA mapping of social-biological interactions in Brazilian Amazonian African-descendant populations

    Directory of Open Access Journals (Sweden)

    Bruno Maia Carvalho

    2008-01-01

    Full Text Available The formation of the Brazilian Amazonian population has historically involved three main ethnic groups, Amerindian, African and European. This has resulted in genetic investigations having been carried out using classical polymorphisms and molecular markers. To better understand the genetic variability and the micro-evolutionary processes acting in human groups in the Brazilian Amazon region we used mitochondrial DNA to investigate 159 maternally unrelated individuals from five Amazonian African-descendant communities. The mitochondrial lineage distribution indicated a contribution of 50.2% from Africans (L0, L1, L2, and L3, 46.6% from Amerindians (haplogroups A, B, C and D and a small European contribution of 1.3%. These results indicated high genetic diversity in the Amerindian and African lineage groups, suggesting that the Brazilian Amazonian African-descendant populations reflect a possible population amalgamation of Amerindian women from different Amazonian indigenous tribes and African women from different geographic regions of Africa who had been brought to Brazil as slaves. The present study partially mapped the historical biological and social interactions that had occurred during the formation and expansion of Amazonian African-descendant communities.

  15. A comparison of genetic map distance and linkage disequilibrium between 15 polymorphic dinucleotide repeat loci in two populations

    Energy Technology Data Exchange (ETDEWEB)

    Urbanek, M.; Goldman, D.; Long, J.C. [Lab. of Neurogenetics, Rockville, MD (United States)

    1994-09-01

    Linkage disequilibrium has recently been used to map the diastrophic dysplasia gene in a Finnish sample. One advantage of this method is that the large pedigrees required by some other methods are unnecessary. Another advantage is that linkage disequilibrium mapping capitalizes on the cumulative history of recombination events, rather than those occurring within the sampled individuals. A potential limitation of linkage disequilibrium mapping is that linkage equilibrium is likely to prevail in all but the most isolated populations, e.g., those which have recently experienced founder effects or severe population bottlenecks. In order to test the method`s generality, we examined patterns of linkage disequilibrium between pairs of loci within a known genetic map. Two populations were analyzed. The first population, Navajo Indians (N=45), is an isolate that experienced a severe bottleneck in the 1860`s. The second population, Maryland Caucasians (N=45), is cosmopolitan. We expected the Navajo sample to display more linkage disequilibrium than the Caucasian sample, and possibly that the Navajo disequilibrium pattern would reflect the genetic map. Linkage disequilibrium coefficients were estimated between pairs of alleles at different loci using maximum likelihood. The genetic isolate structure of Navajo Indians is confirmed by the DNA typings. Heterozygosity is lower than in the Caucasians, and fewer different alleles are observed. However, a relationship between genetic map distance and linkage disequilibrium could be discerned in neither the Navajo nor the Maryland samples. Slightly more linkage disequilibrium was observed in the Navajos, but both data sets were characterized by very low disequilibrium levels. We tentatively conclude that linkage disequilibrium mapping with dinucleotide repeats will only be useful with close linkage between markers and diseases, even in very isolated populations.

  16. Intraspecific Competition and Inbreeding Depression: Increased Competitive Effort by Inbred Males Is Costly to Outbred Opponents.

    Science.gov (United States)

    Richardson, Jon; Smiseth, Per T

    2017-05-01

    A recent theoretical model suggests that intraspecific competition is an important determinant of the severity of inbreeding depression. The reason for this is that intraspecific competition is density dependent, leading to a stronger negative effect on inbred individuals if they are weaker competitors than outbred ones. In support of this prediction, previous empirical work shows that inbred individuals are weaker competitors than outbred ones and that intraspecific competition often exacerbates inbreeding depression. Here, we report an experiment on the burying beetle Nicrophorus vespilloides, in which we recorded the outcome of competition over a small vertebrate carcass between an inbred or outbred male resident caring for a brood and a size-matched inbred or outbred male intruder. We found that inbred males were more successful as intruders in taking over a carcass from a male resident and were injured more frequently as either residents or intruders. Furthermore, inbred males gained less mass during the breeding attempt and had a shorter adult life span than outbred males. Finally, successful resident males reared a substantially smaller brood comprised of lighter larvae when the intruder was inbred than when it was outbred. Our results shows that inbred males increased their competitive effort, thus contradicting previous work suggesting that inbred males are weaker competitors. Furthermore, our results shows that inbred intruders impose a greater cost to resident males, suggesting that outbred individuals can suffer fitness costs as a result of competition with inbred ones.

  17. Mapping of Novel QTL Regulating Grain Shattering Using Doubled Haploid Population in Rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Gyu-Ho Lee

    2016-01-01

    Full Text Available The critical evolutionary step during domestication of major cereals was elimination of seed shattering because the easy-to-shatter trait in wild relatives results in a severe reduction in yield. In this study, we analyzed the QTLs associated with shattering employing a high-density genetic map in doubled haploid (DH population of rice (Oryza sativa L.. A genetic linkage map was generated with 217 microsatellite markers spanning 2082.4 cM and covering 12 rice chromosomes with an average interval of 9.6 cM between markers based on 120 DHLs derived from a cross between Cheongcheong indica type cultivar and Nagdong japonica type cultivar. In the QTL analysis, five QTLs pertaining to the breaking tensile strength (BTS were detected in 2013 and 2015. Two regions of the QTLs related to BTS on chromosome 1 and chromosome 6 were detected. Several important genes are distributed in 1 Mbp region of the QTL on chromosome 6 and they are related to the formation of abscission layer. We decide to name this QTL qSh6 and the candidate genes in the qSh6 region can be employed usefully in further research for cloning.

  18. Mapping of Novel QTL Regulating Grain Shattering Using Doubled Haploid Population in Rice (Oryza sativa L.).

    Science.gov (United States)

    Lee, Gyu-Ho; Kang, In-Kyu; Kim, Kyung-Min

    2016-01-01

    The critical evolutionary step during domestication of major cereals was elimination of seed shattering because the easy-to-shatter trait in wild relatives results in a severe reduction in yield. In this study, we analyzed the QTLs associated with shattering employing a high-density genetic map in doubled haploid (DH) population of rice (Oryza sativa L.). A genetic linkage map was generated with 217 microsatellite markers spanning 2082.4 cM and covering 12 rice chromosomes with an average interval of 9.6 cM between markers based on 120 DHLs derived from a cross between Cheongcheong indica type cultivar and Nagdong japonica type cultivar. In the QTL analysis, five QTLs pertaining to the breaking tensile strength (BTS) were detected in 2013 and 2015. Two regions of the QTLs related to BTS on chromosome 1 and chromosome 6 were detected. Several important genes are distributed in 1 Mbp region of the QTL on chromosome 6 and they are related to the formation of abscission layer. We decide to name this QTL qSh6 and the candidate genes in the qSh6 region can be employed usefully in further research for cloning.

  19. Comparing different stimulus configurations for population receptive field mapping in human fMRI

    Directory of Open Access Journals (Sweden)

    Ivan eAlvarez

    2015-02-01

    Full Text Available Population receptive field (pRF mapping is a widely used approach to measuring aggregate human visual receptive field properties by recording non-invasive signals using functional MRI. Despite growing interest, no study to date has systematically investigated the effects of different stimulus configurations on pRF estimates from human visual cortex. Here we compared the effects of three different stimulus configurations on a model-based approach to pRF estimation: size-invariant bars and eccentricity-scaled bars defined in Cartesian coordinates and traveling along the cardinal axes, and a novel simultaneous ‘wedge and ring’ stimulus defined in polar coordinates, systematically covering polar and eccentricity axes. We found that the presence or absence of eccentricity scaling had a significant effect on goodness of fit and pRF size estimates. Further, variability in pRF size estimates was directly influenced by stimulus configuration, particularly for higher visual areas including V5/MT+. Finally, we compared eccentricity estimation between phase-encoded and model-based pRF approaches. We observed a tendency for more peripheral eccentricity estimates using phase-encoded methods, independent of stimulus size. We conclude that both eccentricity scaling and polar rather than Cartesian stimulus configuration are important considerations for optimal experimental design in pRF mapping. While all stimulus configurations produce adequate estimates, simultaneous wedge and ring stimulation produced higher fit reliability, with a significant advantage in reduced acquisition time.

  20. Geospatial Technology in Disease Mapping, E- Surveillance and Health Care for Rural Population in South India

    Science.gov (United States)

    Praveenkumar, B. A.; Suresh, K.; Nikhil, A.; Rohan, M.; Nikhila, B. S.; Rohit, C. K.; Srinivas, A.

    2014-11-01

    Providing Healthcare to rural population has been a challenge to the medical service providers especially in developing countries. For this to be effective, scalable and sustainable, certain strategic decisions have to be taken during the planning phase. Also, there is a big gap between the services available and the availability of doctors and medical resources in rural areas. Use of Information Technology can aid this deficiency to a good extent. In this paper, a mobile application has been developed to gather data from the field. A cloud based interface has been developed to store the data in the cloud for effective usage and management of the data. A decision tree based solution developed in this paper helps in diagnosing a patient based on his health parameters. Interactive geospatial maps have been developed to provide effective data visualization facility. This will help both the user community as well as decision makers to carry out long term strategy planning.

  1. Mean-field dynamics of a population of stochastic map neurons

    Science.gov (United States)

    Franović, Igor; Maslennikov, Oleg V.; Bačić, Iva; Nekorkin, Vladimir I.

    2017-07-01

    We analyze the emergent regimes and the stimulus-response relationship of a population of noisy map neurons by means of a mean-field model, derived within the framework of cumulant approach complemented by the Gaussian closure hypothesis. It is demonstrated that the mean-field model can qualitatively account for stability and bifurcations of the exact system, capturing all the generic forms of collective behavior, including macroscopic excitability, subthreshold oscillations, periodic or chaotic spiking, and chaotic bursting dynamics. Apart from qualitative analogies, we find a substantial quantitative agreement between the exact and the approximate system, as reflected in matching of the parameter domains admitting the different dynamical regimes, as well as the characteristic properties of the associated time series. The effective model is further shown to reproduce with sufficient accuracy the phase response curves of the exact system and the assembly's response to external stimulation of finite amplitude and duration.

  2. Improved Mapping of Human Population and Settlements through Integration of Remote Sensing and Socioeconomic Data

    Science.gov (United States)

    de Sherbinin, A. M.; Yetman, G.; MacManus, K.; Vinay, S.

    2017-12-01

    The diversity of data on human settlements, infrastructure, and population continues to grow rapidly, with recent releases of data products based on a range of different remote sensing data sources as well as census and administrative data. We report here on recent improvements in data from the NASA Socioeconomic Data and Applications Center (SEDAC) and partner organizations, aimed at supporting both interdisciplinary research and real-world applications. The fourth version of SEDAC's Gridded Population of the World (GPWv4) now includes variables for age categories, gender, and urban/rural location, and has also been integrated with the Global Human Settlements (GHS) data developed by the Joint Research Centre of the European Commission to produce a GHS-POP grid for the years 1975, 1990, 2000 and 2015. Through a collaboration between Facebook's Connectivity Lab and the Center for International Earth Science Information Network (CIESIN), High Resolution Settlement Layer (HRSL) data derived from 50-cm DigitalGlobe imagery are now available for selected developing countries at 30-m resolution. SEDAC is also developing interactive mapping and analysis tools to facilitate visualization and access to these often large and complex data products. For example, SEDAC has collaborated with scientists from NASA's Goddard Space Flight Center to release the Global Man-made Impervious Surfaces & Settlement Extents from Landsat data at 30-m resolution through an innovative map interface. We also summarize recent progress in developing an international data collective that is bringing together both data developers and data users from the public and private sectors to collaborate on expanding data access and use, improving data quality and documentation, facilitating data intercomparison and integration, and sharing of resources and capabilities.

  3. Noninvasive methods for dynamic mapping of microbial populations across the landscape

    Science.gov (United States)

    Meredith, L. K.; Sengupta, A.; Troch, P. A.; Volkmann, T. H. M.

    2017-12-01

    Soil microorganisms drive key ecosystem processes, and yet characterizing their distribution and activity in soil has been notoriously difficult. This is due, in part, to the heterogeneous nature of their response to changing environmental and nutrient conditions across time and space. These dynamics are challenging to constrain in both natural and experimental systems because of sampling difficulty and constraints. For example, soil microbial sampling at the Landscape Evolution Observatory (LEO) infrastructure in Biosphere 2 is limited in efforts to minimize soil disruption to the long term experiment that aims to characterize the interacting biological, hydrological, and geochemical processes driving soil evolution. In this and other systems, new methods are needed to monitor soil microbial communities and their genetic potential over time. In this study, we take advantage of the well-defined boundary conditions on hydrological flow at LEO to develop a new method to nondestructively characterize in situ microbial populations. In our approach, we sample microbes from the seepage flow at the base of each of three replicate LEO hillslopes and use hydrological models to `map back' in situ microbial populations. Over the course of a 3-month periodic rainfall experiment we collected samples from the LEO outflow for DNA and extraction and microbial community composition analysis. These data will be used to describe changes in microbial community composition over the course of the experiment. In addition, we will use hydrological flow models to identify the changing source region of discharge water over the course of periodic rainfall pulses, thereby mapping back microbial populations onto their geographic origin in the slope. These predictions of in situ microbial populations will be ground-truthed against those derived from destructive soil sampling at the beginning and end of the rainfall experiment. Our results will show the suitability of this method for long

  4. A molecular recombination map of Antirrhinum majus

    Directory of Open Access Journals (Sweden)

    Hudson Andrew

    2010-12-01

    Full Text Available Abstract Background Genetic recombination maps provide important frameworks for comparative genomics, identifying gene functions, assembling genome sequences and for breeding. The molecular recombination map currently available for the model eudicot Antirrhinum majus is the result of a cross with Antirrhinum molle, limiting its usefulness within A. majus. Results We created a molecular linkage map of A. majus based on segregation of markers in the F2 population of two inbred lab strains of A. majus. The resulting map consisted of over 300 markers in eight linkage groups, which could be aligned with a classical recombination map and the A. majus karyotype. The distribution of recombination frequencies and distorted transmission of parental alleles differed from those of a previous inter-species hybrid. The differences varied in magnitude and direction between chromosomes, suggesting that they had multiple causes. The map, which covered an estimated of 95% of the genome with an average interval of 2 cM, was used to analyze the distribution of a newly discovered family of MITE transposons and tested for its utility in positioning seven mutations that affect aspects of plant size. Conclusions The current map has an estimated interval of 1.28 Mb between markers. It shows a lower level of transmission ratio distortion and a longer length than the previous inter-species map, making it potentially more useful. The molecular recombination map further indicates that the IDLE MITE transposons are distributed throughout the genome and are relatively stable. The map proved effective in mapping classical morphological mutations of A. majus.

  5. Caenorhabditis briggsae recombinant inbred line genotypes reveal inter-strain incompatibility and the evolution of recombination.

    Directory of Open Access Journals (Sweden)

    Joseph A Ross

    2011-07-01

    Full Text Available The nematode Caenorhabditis briggsae is an emerging model organism that allows evolutionary comparisons with C. elegans and exploration of its own unique biological attributes. To produce a high-resolution C. briggsae recombination map, recombinant inbred lines were generated from reciprocal crosses between two strains and genotyped at over 1,000 loci. A second set of recombinant inbred lines involving a third strain was also genotyped at lower resolution. The resulting recombination maps exhibit discrete domains of high and low recombination, as in C. elegans, indicating these are a general feature of Caenorhabditis species. The proportion of a chromosome's physical size occupied by the central, low-recombination domain is highly correlated between species. However, the C. briggsae intra-species comparison reveals striking variation in the distribution of recombination between domains. Hybrid lines made with the more divergent pair of strains also exhibit pervasive marker transmission ratio distortion, evidence of selection acting on hybrid genotypes. The strongest effect, on chromosome III, is explained by a developmental delay phenotype exhibited by some hybrid F2 animals. In addition, on chromosomes IV and V, cross direction-specific biases towards one parental genotype suggest the existence of cytonuclear epistatic interactions. These interactions are discussed in relation to surprising mitochondrial genome polymorphism in C. briggsae, evidence that the two strains diverged in allopatry, the potential for local adaptation, and the evolution of Dobzhansky-Muller incompatibilities. The genetic and genomic resources resulting from this work will support future efforts to understand inter-strain divergence as well as facilitate studies of gene function, natural variation, and the evolution of recombination in Caenorhabditis nematodes.

  6. Dynamics of phosphorus accumulation in maize inbred lines grain

    Directory of Open Access Journals (Sweden)

    Kovinčić Anika

    2016-01-01

    Full Text Available Mineral elements deficiency in food can cause serious health problems. Being one of the three most importatnt macroelements for plant nutrition, phosphorus is involved in several key processes: photosynthesis, respiration, synthesis of starch, transport of carbohydrates and products of photosynthesis, cell division and increased water utilization. The objective of this study was to estimate the dynamics of inorganic phosphorus (Pi, as a precursor in the synthesis of phytic acid, and phytic phosphorus (Pphy accumulation during the grain filling of two maize inbred lines differing in FAO maturity groups - L217 and L773. In addition, possible linkage between phosphorus content in grain and agro-morphological performances was observed. For the analysis of the dynamics in Pi and Pphy contents, seed samples were taken at 15th, 30th, 45th and 60th day after the polination. The obtained results showed a continuous decline of Pi content in both genotypes, with the most intensive decline observed at the first interval (e.i. 15-30 days after the polination. The trend observed was much more pronounced in L217. Moreover, this inbred acheaved higher grain yield for 61.8 % at first sowing and for 63.1 % at 10-day delayed sowing, respectively, compared to inbred L773. In all three intervals observed, the decrease of Pi content was highly correlated with Pphy content increase for both genotypes. Based on lower accumulation rate, followed by lower Pphy content (2.635 mg g-1 during the stage of physiological maturuty, it could be concluded that inbred L217 could be considered as potentialy suitable genotype for low-phytic hybride selection.

  7. Hemodynamic Characterization of Recombinant Inbred Strains: Twenty Years Later

    Czech Academy of Sciences Publication Activity Database

    Kuneš, Jaroslav; Dobešová, Zdenka; Musilová, Alena; Zídek, Václav; Vorlíček, Jaroslav; Pravenec, Michal; Křen, Vladimír; Zicha, Josef

    2008-01-01

    Roč. 31, č. 8 (2008), s. 1659-1668 ISSN 0916-9636 R&D Projects: GA MŠk(CZ) 1M0510; GA ČR(CZ) GA305/08/0139; GA AV ČR(CZ) IAA500110604 Institutional research plan: CEZ:AV0Z50110509 Keywords : recombinant inbred strains * blood pressure * telemetry Subject RIV: ED - Physiology Impact factor: 3.146, year: 2008

  8. Vaccination with M2e-based multiple antigenic peptides: characterization of the B cell response and protection efficacy in inbred and outbred mice.

    Directory of Open Access Journals (Sweden)

    Amaya I Wolf

    Full Text Available The extracellular domain of the influenza A virus protein matrix protein 2 (M2e is remarkably conserved between various human isolates and thus is a viable target antigen for a universal influenza vaccine. With the goal of inducing protection in multiple mouse haplotypes, M2e-based multiple antigenic peptides (M2e-MAP were synthesized to contain promiscuous T helper determinants from the Plasmodium falciparum circumsporozoite protein, the hepatitis B virus antigen and the influenza virus hemagglutinin. Here, we investigated the nature of the M2e-MAP-induced B cell response in terms of the distribution of antibody (Ab secreting cells (ASCs and Ab isotypes, and tested the protective efficacy in various mouse strains.Immunization of BALB/c mice with M2e-MAPs together with potent adjuvants, CpG 1826 oligonucleotides (ODN and cholera toxin (CT elicited high M2e-specific serum Ab titers that protected mice against viral challenge. Subcutaneous (s.c. and intranasal (i.n. delivery of M2e-MAPs resulted in the induction of IgG in serum and airway secretions, however only i.n. immunization induced anti-M2e IgA ASCs locally in the lungs, correlating with M2-specific IgA in the bronchio-alveolar lavage (BAL. Interestingly, both routes of vaccination resulted in equal protection against viral challenge. Moreover, M2e-MAPs induced cross-reactive and protective responses to diverse M2e peptides and variant influenza viruses. However, in contrast to BALB/c mice, immunization of other inbred and outbred mouse strains did not induce protective Abs. This correlated with a defect in T cell but not B cell responsiveness to the M2e-MAPs.Anti-M2e Abs induced by M2e-MAPs are highly cross-reactive and can mediate protection to variant viruses. Although synthetic MAPs are promising designs for vaccines, future constructs will need to be optimized for use in the genetically heterogeneous human population.

  9. Modeling X-linked ancestral origins in multiparental populations.

    Science.gov (United States)

    Zheng, Chaozhi

    2015-03-04

    The models for the mosaic structure of an individual's genome from multiparental populations have been developed primarily for autosomes, whereas X chromosomes receive very little attention. In this paper, we extend our previous approach to model ancestral origin processes along two X chromosomes in a mapping population, which is necessary for developing hidden Markov models in the reconstruction of ancestry blocks for X-linked quantitative trait locus mapping. The model accounts for the joint recombination pattern, the asymmetry between maternally and paternally derived X chromosomes, and the finiteness of population size. The model can be applied to various mapping populations such as the advanced intercross lines (AIL), the Collaborative Cross (CC), the heterogeneous stock (HS), the Diversity Outcross (DO), and the Drosophila synthetic population resource (DSPR). We further derive the map expansion, density (per Morgan) of recombination breakpoints, in advanced intercross populations with L inbred founders under the limit of an infinitely large population size. The analytic results show that for X chromosomes the genetic map expands linearly at a rate (per generation) of two-thirds times 1 - 10/(9L) for the AIL, and at a rate of two-thirds times 1 - 1/L for the DO and the HS, whereas for autosomes the map expands at a rate of 1 - 1/L for the AIL, the DO, and the HS. Copyright © 2015 Zheng.

  10. SSR markers in characterization of sweet corn inbred lines

    Directory of Open Access Journals (Sweden)

    Srdić Jelena

    2008-01-01

    Full Text Available Sweet corn differs from field corn in many important traits. So its breeding although includes some standard procedures demand application of techniques that are important for determining special traits, all because of the specificity of its usage. Application of molecular markers becomes almost a necessity for the breeding of sweet corn, especially because this is the type of maize in which still no definitive heterotic patterns have been determined. So getting to know genetic divergence of the sweet corn inbred lines is of great importance for its breeding. In this paper we analyzed genetic similarity of six sweet corn inbreds based on SSR markers. 40 SSR primers were used in DNA amplification. Results were compared and correlated with the data on specific combining ability, obtained by the diallel analysis. The results of SCA were in concurrence with genetic similarity. Values of rank correlation coefficient were negative, indicating that more similar inbred lines had smaller estimates of SCA, and lines that were less similar had higher estimates of SCA. Rank correlation coefficient between SCA and GS according to Dice coefficient was between -0,16 and -0,57*.

  11. Revealing the Complexity in CD8 T Cell Responses to Infection in Inbred C57B/6 versus Outbred Swiss Mice.

    Science.gov (United States)

    Martin, Matthew D; Danahy, Derek B; Hartwig, Stacey M; Harty, John T; Badovinac, Vladimir P

    2017-01-01

    Recent work has suggested that current mouse models may underrepresent the complexity of human immune responses. While most mouse immunology studies utilize inbred mouse strains, it is unclear if conclusions drawn from inbred mice can be extended to all mouse strains or generalized to humans. We recently described a "surrogate activation marker" approach that could be used to track polyclonal CD8 T cell responses in inbred and outbred mice and noted substantial discord in the magnitude and kinetics of CD8 T cell responses in individual outbred mice following infection. However, how the memory CD8 T cell response develops following infection and the correlates of memory CD8 T cell-mediated protection against re-infection in outbred mice remains unknown. In this study, we investigated development of pathogen-specific memory CD8 T cell responses in inbred C57B/6 and outbred National Institutes of Health Swiss mice following lymphocytic choriomeningitis virus or L. monocytogenes infection. Interestingly, the size of the memory CD8 T cell pool generated and rate of phenotypic progression was considerably more variable in individual outbred compared to inbred mice. Importantly, while prior infection provided both inbred and outbred cohorts of mice with protection against re-infection that was dependent on the dose of primary infection, levels of memory CD8 T cells generated and degree of protection against re-infection did not correlate with primary infection dose in all outbred mice. While variation in CD8 T cell responses to infection is not entirely surprising due to the genetic diversity present, analysis of infection-induced immunity in outbred hosts may reveal hidden complexity in CD8 T cell responses in genetically diverse populations and might help us further bridge the gap between mouse and human studies.

  12. Population-Based Trachoma Mapping in Six Evaluation Units of Papua New Guinea.

    Science.gov (United States)

    Ko, Robert; Macleod, Colin; Pahau, David; Sokana, Oliver; Keys, Drew; Burnett, Anthea; Willis, Rebecca; Wabulembo, Geoffrey; Garap, Jambi; Solomon, Anthony W

    2016-01-01

    We sought to determine the prevalence of trachomatous inflammation - follicular (TF) in children aged 1-9 years, and trachomatous trichiasis (TT) in those aged ≥15 years, in suspected trachoma-endemic areas of Papua New Guinea (PNG). We carried out six population-based prevalence surveys using the protocol developed as part of the Global Trachoma Mapping Project. A total of 19,013 individuals were sampled for inclusion, with 15,641 (82.3%) consenting to participate. Four evaluation units had prevalences of TF in children ≥10%, above which threshold the World Health Organization (WHO) recommends mass drug administration (MDA) of azithromycin for at least three years; Western Province (South Fly/Daru) 11.2% (95% confidence interval, CI, 6.9-17.0%), Southern Highlands (East) 12.2% (95% CI 9.6-15.0%), Southern Highlands (West) 11.7% (95% CI 8.5-15.3%), and West New Britain 11.4% (95% CI 8.7-13.9%). TF prevalence was 5.0-9.9% in Madang (9.4%, 95% CI 6.1-13.0%) and National Capital District (6.0%. 95% CI 3.2-9.1%) where consideration of a single round of MDA is warranted. Cases of TT were not found outside West New Britain, in which four cases were seen, generating an estimated population-level prevalence of TT in adults of 0.10% (95% CI 0.00-0.40%) for West New Britain, below the WHO elimination threshold of 0.2% of those aged ≥15 years. Trachoma is a public health issue in PNG. However, other than in West New Britain, there are few data to support the idea that trachoma is a cause of blindness in PNG. Further research is needed to understand the stimulus for the active trachoma phenotype in these populations.

  13. Identification of QTL for drought tolerance and characterization of extreme phenotypes in the Buster x Roza mapping population

    Science.gov (United States)

    Terminal and intermittent drought limits dry bean production worldwide.The Buster/Roza mapping population (140 F7:9 RILs) has been screened for drought tolerance across multiple years/locations. In 2011 and 2012 the RILs were tested for terminal drought response at two locations: Othello, WA and Sco...

  14. QTL mapping for microtuber dormancy and GA3content in a diploid potato population.

    Science.gov (United States)

    Naz, Raja Mohib Muazzam; Li, Mengtai; Ramzan, Safia; Li, Gege; Liu, Jun; Cai, Xingkui; Xie, Conghua

    2018-01-23

    The genetic control of dormancy is poorly understood in most plant species, but dormancy is a prominent feature for the potato industry. We used the microtuber system, in which tubers were produced in vitro and stored at 20°C, to perform quantitative trait locus (QTL) analysis for dormancy and gibberellic acid (GA 3 ) content in an F 1 population consisting of 178 genotypes derived from an interspecific cross between Solanum chacoense acc. PI 320285 (long dormancy) and Solanum phureja acc. DM1-3 516 R44 (short dormancy). In this analysis, 163 markers were used to construct a genetic map with a total length of 591.8 cM. Through QTL analysis, we identified 22 markers closely linked to the timing of dormancy release and GA 3 content. The male parent alleles were closely related with long dormancy, with the most significant effect on chromosome I, which accounted for 9.4% of phenotypic variation. The dormancy and GA 3 QTLs localized to the same position in the genome, confirming that same genomic region controls GA 3 content at different developmental stages or in dormant and sprouting tubers. The identified QTLs may be useful for future breeding strategies and studies of dormancy in potato. © 2018. Published by The Company of Biologists Ltd.

  15. Quantitative trait Loci association mapping by imputation of strain origins in multifounder crosses.

    Science.gov (United States)

    Zhou, Jin J; Ghazalpour, Anatole; Sobel, Eric M; Sinsheimer, Janet S; Lange, Kenneth

    2012-02-01

    Although mapping quantitative traits in inbred strains is simpler than mapping the analogous traits in humans, classical inbred crosses suffer from reduced genetic diversity compared to experimental designs involving outbred animal populations. Multiple crosses, for example the Complex Trait Consortium's eight-way cross, circumvent these difficulties. However, complex mating schemes and systematic inbreeding raise substantial computational difficulties. Here we present a method for locally imputing the strain origins of each genotyped animal along its genome. Imputed origins then serve as mean effects in a multivariate Gaussian model for testing association between trait levels and local genomic variation. Imputation is a combinatorial process that assigns the maternal and paternal strain origin of each animal on the basis of observed genotypes and prior pedigree information. Without smoothing, imputation is likely to be ill-defined or jump erratically from one strain to another as an animal's genome is traversed. In practice, one expects to see long stretches where strain origins are invariant. Smoothing can be achieved by penalizing strain changes from one marker to the next. A dynamic programming algorithm then solves the strain imputation process in one quick pass through the genome of an animal. Imputation accuracy exceeds 99% in practical examples and leads to high-resolution mapping in simulated and real data. The previous fastest quantitative trait loci (QTL) mapping software for dense genome scans reduced compute times to hours. Our implementation further reduces compute times from hours to minutes with no loss in statistical power. Indeed, power is enhanced for full pedigree data.

  16. Analysis of microsatellite polymorphism in inbred knockout mice.

    Directory of Open Access Journals (Sweden)

    Baofen Zuo

    Full Text Available Previously, we found that the genotype of 42 out of 198 mouse microsatellite loci, which are distributed among all chromosomes except the Y chromosome, changed from monomorphism to polymorphism (CMP in a genetically modified inbred mouse strain. In this study, we further examined whether CMP also relates to the homologous recombination in gene knockout (KO mouse strains. The same 42 microsatellite loci were analyzed by polymerase chain reaction (PCR in 29 KO inbred mouse strains via short tandem sequence repeat (STR scanning and direct sequence cloning to justify microsatellite polymorphisms. The C57BL/6J and 129 mouse strains, from which these 29 KO mice were derived, were chosen as the background controls. The results indicated that 10 out of 42 (23.8% loci showed CMP in some of these mouse strains. Except for the trinucleotide repeat locus of D3Mit22, which had microsatellite CMP in strain number 9, the core sequences of the remaining 41 loci were dinucleotide repeats, and 9 out of 41 (21.95% showed CMPs among detected mouse strains. However, 11 out of 29 (37.9% KO mice strains were recognized as having CMPs. The popular dinucleotide motifs in CMP were (TG(n (50%, 2/4, followed by (GT(n (27.27%, 3/11 and (CA(n (23.08%, 3/13. The microsatellite CMP in (CT(n and (AG(n repeats were 20% (1/5. According to cloning sequencing results, 6 KO mouse strains showed insertions of nucleotides whereas 1 showed a deletion. Furthermore, 2 loci (D13Mit3 and D14Mit102 revealed CMP in 2 strains, and mouse strain number 9 showed CMPs in two loci (D3Mit22 and D13Mit3 simultaneously. Collectively, these results indicated that microsatellite polymorphisms were present in the examined inbred KO mice.

  17. SSR-based association mapping of fiber quality in upland cotton using an eight-way MAGIC population.

    Science.gov (United States)

    Huang, Cong; Shen, Chao; Wen, Tianwang; Gao, Bin; Zhu, De; Li, Xiaofang; Ahmed, Muhammad Mahmood; Li, Dingguo; Lin, Zhongxu

    2018-02-01

    The quality of fiber is significant in the upland cotton industry. As complex quantitative traits, fiber quality traits are worth studying at a genetic level. To investigate the genetic architecture of fiber quality traits, we conducted an association analysis using a multi-parent advanced generation inter-cross (MAGIC) population developed from eight parents and comprised of 960 lines. The reliable phenotypic data for six major fiber traits of the MAGIC population were collected from five environments in three locations. Phenotypic analysis showed that the MAGIC lines have a wider variation amplitude and coefficient than the founders. A total of 284 polymorphic SSR markers among eight parents screened from a high-density genetic map were used to genotype the MAGIC population. The MAGIC population showed abundant genetic variation and fast linkage disequilibrium (LD) decay (0.76 cM, r 2  > 0.1), which revealed the advantages of high efficiency and power in QTL exploration. Association mapping via a mixed linear model identified 52 significant loci associated with six fiber quality traits; 14 of them were mapped in reported QTL regions with fiber-related or other agronomic traits. Nine markers demonstrated the pleiotropism that controls more than two fiber traits. Furthermore, two SSR markers, BNL1231 and BNL3452, were authenticated as hotspots that were mapped with multi-traits. In addition, we provided candidate regions and screened six candidate genes for identified loci according to the LD decay distance. Our results provide valuable QTL for further genetic mapping and will facilitate marker-based breeding for fiber quality in cotton.

  18. Combined linkage and association mapping reveals candidates for Scmv1, a major locus involved in resistance to sugarcane mosaic virus (SCMV) in maize.

    Science.gov (United States)

    Tao, Yongfu; Jiang, Lu; Liu, Qingqing; Zhang, Yan; Zhang, Rui; Ingvardsen, Christina Roenn; Frei, Ursula Karoline; Wang, Baobao; Lai, Jinsheng; Lübberstedt, Thomas; Xu, Mingliang

    2013-10-18

    Sugarcane mosaic virus (SCMV) disease causes substantial losses of grain yield and forage biomass in susceptible maize cultivars. Maize resistance to SCMV is associated with two dominant genes, Scmv1 and Scmv2, which are located on the short arm of chromosome 6 and near the centromere region of chromosome 3, respectively. We combined both linkage and association mapping to identify positional candidate genes for Scmv1. Scmv1 was fine-mapped in a segregating population derived from near-isogenic lines and further validated and fine-mapped using two recombinant inbred line populations. The combined results assigned the Scmv1 locus to a 59.21-kb interval, and candidate genes within this region were predicted based on the publicly available B73 sequence. None of three predicted genes that are possibly involved in the disease resistance response are similar to receptor-like resistance genes. Candidate gene-based association mapping was conducted using a panel of 94 inbred lines with variable resistance to SCMV. A presence/absence variation (PAV) in the Scmv1 region and two polymorphic sites around the Zmtrx-h gene were significantly associated with SCMV resistance. Combined linkage and association mapping pinpoints Zmtrx-h as the most likely positional candidate gene for Scmv1. These results pave the way towards cloning of Scmv1 and facilitate marker-assisted selection for potyvirus resistance in maize.

  19. Mapping the distinctive populations of lymphatic endothelial cells in different zones of human lymph nodes.

    Directory of Open Access Journals (Sweden)

    Saem Mul Park

    Full Text Available The lymphatic sinuses in human lymph nodes (LNs are crucial to LN function yet their structure remains poorly defined. Much of our current knowledge of lymphatic sinuses derives from rodent models, however human LNs differ substantially in their sinus structure, most notably due to the presence of trabeculae and trabecular lymphatic sinuses that rodent LNs lack. Lymphatic sinuses are bounded and traversed by lymphatic endothelial cells (LECs. A better understanding of LECs in human LNs is likely to improve our understanding of the regulation of cell trafficking within LNs, now an important therapeutic target, as well as disease processes that involve lymphatic sinuses. We therefore sought to map all the LECs within human LNs using multicolor immunofluorescence microscopy to visualize the distribution of a range of putative markers. PROX1 was the only marker that uniquely identified the LECs lining and traversing all the sinuses in human LNs. In contrast, LYVE1 and STAB2 were only expressed by LECs in the paracortical and medullary sinuses in the vast majority of LNs studied, whilst the subcapsular and trabecular sinuses lacked these molecules. These data highlight the existence of at least two distinctive populations of LECs within human LNs. Of the other LEC markers, we confirmed VEGFR3 was not specific for LECs, and CD144 and CD31 stained both LECs and blood vascular endothelial cells (BECs; in contrast, CD59 and CD105 stained BECs but not LECs. We also showed that antigen-presenting cells (APCs in the sinuses could be clearly distinguished from LECs by their expression of CD169, and their lack of expression of PROX1 and STAB2, or endothelial markers such as CD144. However, both LECs and sinus APCs were stained with DCN46, an antibody commonly used to detect CD209.

  20. Visual cortex in aging and Alzheimer's disease: changes in visual field maps and population receptive fields

    Science.gov (United States)

    Brewer, Alyssa A.; Barton, Brian

    2012-01-01

    Although several studies have suggested that cortical alterations underlie such age-related visual deficits as decreased acuity, little is known about what changes actually occur in visual cortex during healthy aging. Two recent studies showed changes in primary visual cortex (V1) during normal aging; however, no studies have characterized the effects of aging on visual cortex beyond V1, important measurements both for understanding the aging process and for comparison to changes in age-related diseases. Similarly, there is almost no information about changes in visual cortex in Alzheimer's disease (AD), the most common form of dementia. Because visual deficits are often reported as one of the first symptoms of AD, measurements of such changes in the visual cortex of AD patients might improve our understanding of how the visual system is affected by neurodegeneration as well as aid early detection, accurate diagnosis and timely treatment of AD. Here we use fMRI to first compare the visual field map (VFM) organization and population receptive fields (pRFs) between young adults and healthy aging subjects for occipital VFMs V1, V2, V3, and hV4. Healthy aging subjects do not show major VFM organizational deficits, but do have reduced surface area and increased pRF sizes in the foveal representations of V1, V2, and hV4 relative to healthy young control subjects. These measurements are consistent with behavioral deficits seen in healthy aging. We then demonstrate the feasibility and first characterization of these measurements in two patients with mild AD, which reveal potential changes in visual cortex as part of the pathophysiology of AD. Our data aid in our understanding of the changes in the visual processing pathways in normal aging and provide the foundation for future research into earlier and more definitive detection of AD. PMID:24570669

  1. Characterization of opaque2 modifier QTLs and candidate genes in recombinant inbred lines derived from the K0326Y quality protein maize inbred

    KAUST Repository

    Holding, David R.

    2010-11-13

    Quality protein maize (QPM) is a high lysine-containing corn that is based on genetic modification of the opaque2 (o2) mutant. In QPM, modifier genes convert the starchy endosperm of o2 to the vitreous phenotype of wild type maize. There are multiple, unlinked o2 modifier loci (Opm) in QPM and their nature and mode of action are unknown. We previously identified seven Opm QTLs and characterized 16 genes that are differentially up-regulated at a significant level in K0326Y QPM, compared to the starchy endosperm mutant W64Ao2. In order to further characterize these Opm QTLs and the genes up-regulated in K0326Y QPM, we created a population of 314 recombinant inbred lines (RILs) from a cross between K0326Y QPM and W64Ao2. The RILs were characterized for three traits associated with endosperm texture: vitreousness, density and hardness. Genetic linkage analysis of the RIL population confirmed three of the previously identified QTLs associated with o2 endosperm modification in K0326Y QPM. Many of the genes up-regulated in K0326Y QPM showed substantially higher levels of expression in vitreous compared with opaque RILs. These included genes associated with the upstream regulation of the ethylene response pathway, and a gene encoding a regulatory subunit of pyrophosphate-dependent fructose-6-phosphate 1-phosphotransferase, an adaptive enzyme of the glycolytic pathway. © 2010 Springer-Verlag.

  2. Evaluation of Drought Tolerance of Bread Wheat Recombinant Inbred Lines

    Directory of Open Access Journals (Sweden)

    N Zafar Naderi

    2014-10-01

    Full Text Available To evaluateresponse of bread wheat recombinant inbred lines to water deficit, a split plot experiment arranged in randomized complete block design (CRBD was conducted using eight recombinant inbred lines and their parental cultivars (Roshan and Super Head with three replications under three irrigation levels (80, 120 and 160 mm evaporation from class A pan at the Agriculture Research Station of Islamic Azad University, Tabriz Branch during 2009. The results of analysis of variance data collected revealed significant difference among lines and irrigation levels for grain yield. While line × irrigation level interaction was non significant for grain yield. Based on SSI and TOL, drought tolerance indices lines number 1, 7, 41 and Roshan cultivar under 120 mm evaporation, and lines number 7 and 19 under 160 mm evaporation were the tolerant lines. Under both stress conditions according to STI, MP and GMP indices, lines number 37, 38 and Roshan cultivar were recognized as the tolerant lines to water deficiet. Cluster analyses based on grain yield and drought tolerance indices recognized the lines number 1, 30, 32, 37, 38, 41 and Roshan cultivar under 120 mm and lines number 30, 37 and 38 and Roshan under 160 mm evaporation as the most drought tolerants and higher producers.

  3. Association Mapping of Ferrous, Zinc, and Aluminum Tolerance at the Seedling Stage in Indica Rice using MAGIC Populations

    Directory of Open Access Journals (Sweden)

    Lijun Meng

    2017-10-01

    Full Text Available Excessive amounts of metal are toxic and severely affect plant growth and development. Understanding the genetic control of metal tolerance is crucial to improve rice resistance to Fe, Zn, and Al toxicity. The multi-parent advanced generation inter-cross (MAGIC populations were genotyped using a 55 K rice SNP array and screened at the seedling stage for Fe, Zn, and Al toxicity using a hydroponics system. Association analysis was conducted by implementing a mixed linear model (MLM for each of the five MAGIC populations double cross DC1 (founders were SAGC-08, HHZ5-SAL9-Y3-Y1, BP1976B-2-3-7-TB-1-1, PR33282-B-8-1-1-1-1-1, double cross DC2 (founders of double cross were FFZ1, CT 16658-5-2-2SR-2-3-6MP, IR 68, IR 02A127, eight parents population 8way (founders were SAGC-08, HHZ5-SAL9-Y3-Y1, BP1976B-2-3-7-TB-1-1, PR33282-B-8-1-1-1-1-1, FFZ1, CT 16658-5-2-2SR-2-3-6MP, IR 68, IR 02A127, DC12 (DC1+DC2 and rice multi-parent recombinant inbred line population RMPRIL (DC1+DC2+8way. A total of 21, 30, and 21 QTL were identified for Fe, Zn, and Al toxicity tolerance, respectively. For multi tolerance (MT as Fe, Zn, and Al tolerance-related traits, three genomic regions, MT1.1 (chr.1: 35.4–36.3 Mb, MT1.2 (chr.1: 35.4–36.3 Mb, and MT3.2 (chr.3: 35.4-36.2 Mb harbored QTL. The chromosomal regions MT2.1 (chr.2: 2.4–2.8 Mb, MT2.2 (chr.2: 24.5–25.8 Mb, MT4 (chr.4: 1.2 Mb Mb, MT8.1 (chr.8: 0.7–0.9 Mb, and MT8.2 (chr.8: 2.2–2.4 Mb harbored QTL for Fe and Zn tolerance, while MT2.3 (chr.2: 30.5–31.6 Mb, MT3.1 (chr.3: 12.5–12.8 Mb, and MT6 (chr.6: 2.0–3.0 Mb possessed QTL for Al and Zn tolerance. The chromosomal region MT9.1 (chr.9: 14.2–14.7 Mb possessed QTL for Fe and Al tolerance. A total of 11 QTL were detected across different MAGIC populations and 12 clustered regions were detected under different metal conditions, suggesting that these genomic regions might constitute valuable regions for further marker-assisted selection (MAS in breeding

  4. The Combining Ability of Maize Inbred Lines for Grain Yield and ...

    African Journals Online (AJOL)

    This experiment was, therefore, conducted to investigate the general (GCA) and specific (SCA) combining ability of selected maize inbred lines for grain yield and GLS disease resistance. Eight maize inbred lines with contrasting reactions to GLS were crossed in diallel mating to generate 28 hybrids. The parents and ...

  5. Comparison of RAPD, RFLP, AFLP and SSR markers for diversity studies in tropical maize inbred lines

    Directory of Open Access Journals (Sweden)

    Antonio A. F. Garcia

    2004-01-01

    Full Text Available In order to compare their relative efficiencies as markers and to find the most suitable marker for maize diversity studies we evaluated 18 inbred tropical maize lines using a number of different loci as markers. The loci used were: 774 amplified fragment length polymorphisms (AFLPs; 262 random amplified polymorphic DNAs (RAPDs; 185 restriction fragment length polymorphisms (RFLPs; and 68 simple sequence repeats (SSR. For estimating genetic distance the AFLP and RFLP markers gave the most correlated results, with a correlation coefficient of r = 0.87. Bootstrap analysis were used to evaluate the number of loci for the markers and the coefficients of variation (CV revealed a skewed distribution. The dominant markers (AFLP and RAPD had small CV values indicating a skewed distribution while the codominant markers gave high CV values. The use of maximum values of genetic distance CVs within each sample size was efficient in determining the number of loci needed to obtain a maximum CV of 10%. The number of RFLP and AFLP loci used was enough to give CV values of below 5%, while the SSRs and RAPD loci gave higher CV values. Except for the RAPD markers, all the markers correlated genetic distance with single cross performance and heterosis which showed that they could be useful in predicting single cross performance and heterosis in intrapopulation crosses for broad-based populations. Our results indicate that AFLP seemed to be the best-suited molecular assay for fingerprinting and assessing genetic relationships among tropical maize inbred lines with high accuracy.

  6. Genetic analysis in a variant of limb girdle muscular dystrophy in an inbred aboriginal community

    Energy Technology Data Exchange (ETDEWEB)

    Greenberg, C.R.; Nylen, E.G.; Halliday, W. [Univ. of Manitoba, Winnipeg (Canada)] [and others

    1994-09-01

    Limb girdle muscular dystrophy (LGMD) is a heterogeneous group of disorders with variable inheritance patterns, age-of-onset, rates of progression and patterns of muscle involvement. To date, 4 different chromosomal assignments have been described; LGMD1 to chromosome 5q, LGMD2 to chromosome 15q, SCARMD to chromosome 13q and a fourth locus on chromosome 2p. Because of this genetic heterogeneity, only large unambiguous multiplex families which are clearly linked to a particular locus can be utilized in a genetic analysis. We now report preliminary findings in a large highly inbred aboriginal kindred with 8 probands (5 females, 3 males) from 6 nuclear families with a progressive LMD. All presented in their mid- to late teens with gait disturbances. At time of presentation all except one had both proximal as well as distal muscle involvement, facial muscle sparing, CK levels 25 to 100 times normal (3762-20,400 U/l), dystrophic muscle biopsies and normal dystrophin and dystrophin-associated glycoprotein expression. We have studied the segregation of highly informative microsatellite markers for FBN1, D15S132 and the gene for thrombospondin on chromosome 15q and D2S134, D2S136, D2S147, and D2S166 on chromosome 2. Linkage to chromosome 15q has been excluded and two-point lod scores are not significant as yet to either confirm or exclude linkage to chromosome 2p. However, visual inspection reveals that affected individuals are not consistently homozygous for the chromosome 2p markers as would be predicted in such an inbred population. Clinically, SCARMD is unlikely and if the locus on chromosomes 2p and 5q can also be excluded, a genome-wide search using evenly spaced microsatellites will be initiated. A second geographically distinct aboriginal kindred with a similar clinical phenotype has now also been identified.

  7. Resource mapping and emergency preparedness to infectious diseases in human and animal populations in Kibaha and Ngorongoro districts, Tanzania

    OpenAIRE

    E.D. Karimuribo; B. Jones; M.I. Matee; D.M. Kambarage; S. Mounier-Jack; M.M. Rweyemamu

    2012-01-01

    A rapid situation analysis was conducted in Kibaha and Ngorongoro districts in Tanzania to map resources as well as analysing emergency preparedness to infectious diseases in animal (domestic and wild) and human populations. Kibaha was chosen as a district close to a commercial city (Dar es Salaam) while Ngorongoro represented a remote, border district with high interactions between humans, domestic and wild animals. In this study, data on resources and personnel as well as emergency pre...

  8. A Consensus Genetic Map for Pinus taeda and Pinus elliottii and Extent of Linkage Disequilibrium in Two Genotype-Phenotype Discovery Populations of Pinus taeda.

    Science.gov (United States)

    Westbrook, Jared W; Chhatre, Vikram E; Wu, Le-Shin; Chamala, Srikar; Neves, Leandro Gomide; Muñoz, Patricio; Martínez-García, Pedro J; Neale, David B; Kirst, Matias; Mockaitis, Keithanne; Nelson, C Dana; Peter, Gary F; Davis, John M; Echt, Craig S

    2015-06-11

    A consensus genetic map for Pinus taeda (loblolly pine) and Pinus elliottii (slash pine) was constructed by merging three previously published P. taeda maps with a map from a pseudo-backcross between P. elliottii and P. taeda. The consensus map positioned 3856 markers via genotyping of 1251 individuals from four pedigrees. It is the densest linkage map for a conifer to date. Average marker spacing was 0.6 cM and total map length was 2305 cM. Functional predictions of mapped genes were improved by aligning expressed sequence tags used for marker discovery to full-length P. taeda transcripts. Alignments to the P. taeda genome mapped 3305 scaffold sequences onto 12 linkage groups. The consensus genetic map was used to compare the genome-wide linkage disequilibrium in a population of distantly related P. taeda individuals (ADEPT2) used for association genetic studies and a multiple-family pedigree used for genomic selection (CCLONES). The prevalence and extent of LD was greater in CCLONES as compared to ADEPT2; however, extended LD with LGs or between LGs was rare in both populations. The average squared correlations, r(2), between SNP alleles less than 1 cM apart were less than 0.05 in both populations and r(2) did not decay substantially with genetic distance. The consensus map and analysis of linkage disequilibrium establish a foundation for comparative association mapping and genomic selection in P. taeda and P. elliottii. Copyright © 2015 Westbrook et al.

  9. The effective size of the Icelandic population and the prospects for LD mapping: inference from unphased microsatellite markers

    DEFF Research Database (Denmark)

    Bataillon, Thomas; Mailund, Thomas; Thorlacius, Steinunn

    2006-01-01

    Characterizing the extent of linkage disequilibrium (LD) in the genome is a pre-requisite for association mapping studies. Patterns of LD also contain information about the past demography of populations. On this study we focus on the Icelandic population where LD was investigated in 12 regions...... size. Differences in the patterns of decrease of LD with distance among genomic regions were mostly due to two regions exhibiting respectively higher and lower proportions of pairs in LD than average within the first 4 cM. We pooled data from all regions except these two and summarized patterns of LD...... on scaled recombination rates from patterns of LD. Patterns of LD in Iceland suggest a genome-wide scaled recombination rate of ρ* = 200 [130–330] per cM which is equivalent to a long term effective population size of ~5000 in the range of estimates recently reported in three populations using extensive...

  10. Resource mapping and emergency preparedness to infectious diseases in human and animal populations in Kibaha and Ngorongoro districts, Tanzania

    Directory of Open Access Journals (Sweden)

    E.D. Karimuribo

    2012-06-01

    Full Text Available A rapid situation analysis was conducted in Kibaha and Ngorongoro districts in Tanzania to map resources as well as analysing emergency preparedness to infectious diseases in animal (domestic and wild and human populations. Kibaha was chosen as a district close to a commercial city (Dar es Salaam while Ngorongoro represented a remote, border district with high interactions between humans, domestic and wild animals. In this study, data on resources and personnel as well as emergency preparedness were collected from all wards (n = 22, human health facilities (n = 40 and livestock facilities in the two districts using interview checklists and questionnaires. Descriptive statistics for resources were calculated and mapped by district. Kibaha district had a higher human population density, more health workers, better equipped health facilities and better communication and transport systems. On the other hand, Ngorongoro had a higher population of livestock and more animal health facilities but a poorer ratio of animal health workers to livestock. The average ratio of health personnel to population in catchment areas of the health facilities was 1:147 (range of 1:17−1:1200. The ratio of personnel to human population was significantly higher in Kibaha (1:95 than in Ngorongoro (1:203 district (p = 0 < 0.001. Considering the limited resources available to both human and animal health sectors and their different strengths and weaknesses there are opportunities for greater collaboration and resource-sharing between human and animal health for improved surveillance and emergency-preparedness.

  11. Heritability and demographic analyses in the large isolated population of Val Borbera suggest advantages in mapping complex traits genes.

    Directory of Open Access Journals (Sweden)

    Michela Traglia

    2009-10-01

    Full Text Available Isolated populations are a useful resource for mapping complex traits due to shared stable environment, reduced genetic complexity and extended Linkage Disequilibrium (LD compared to the general population. Here we describe a large genetic isolate from the North West Apennines, the mountain range that runs through Italy from the North West Alps to the South.The study involved 1,803 people living in 7 villages of the upper Borbera Valley. For this large population cohort, data from genealogy reconstruction, medical questionnaires, blood, anthropometric and bone status QUS parameters were evaluated. Demographic and epidemiological analyses indicated a substantial genetic component contributing to each trait variation as well as overlapping genetic determinants and family clustering for some traits.The data provide evidence for significant heritability of medical relevant traits that will be important in mapping quantitative traits. We suggest that this population isolate is suitable to identify rare variants associated with complex phenotypes that may be difficult to study in larger but more heterogeneous populations.

  12. Multiparent intercross populations in analysis of quantitative traits

    Indian Academy of Sciences (India)

    2012-04-17

    ). For example in maize the ... recombinant inbred line (AMPRIL) population as an additional resource for dissecting the genetics of natural .... Construction of AMPRIL population. Four founder accessions (P1, P2, P3 and P4) ...

  13. Forward Genetics by Sequencing EMS Variation-Induced Inbred Lines

    Directory of Open Access Journals (Sweden)

    Charles Addo-Quaye

    2017-02-01

    Full Text Available In order to leverage novel sequencing techniques for cloning genes in eukaryotic organisms with complex genomes, the false positive rate of variant discovery must be controlled for by experimental design and informatics. We sequenced five lines from three pedigrees of ethyl methanesulfonate (EMS-mutagenized Sorghum bicolor, including a pedigree segregating a recessive dwarf mutant. Comparing the sequences of the lines, we were able to identify and eliminate error-prone positions. One genomic region contained EMS mutant alleles in dwarfs that were homozygous reference sequences in wild-type siblings and heterozygous in segregating families. This region contained a single nonsynonymous change that cosegregated with dwarfism in a validation population and caused a premature stop codon in the Sorghum ortholog encoding the gibberellic acid (GA biosynthetic enzyme ent-kaurene oxidase. Application of exogenous GA rescued the mutant phenotype. Our method for mapping did not require outcrossing and introduced no segregation variance. This enables work when line crossing is complicated by life history, permitting gene discovery outside of genetic models. This inverts the historical approach of first using recombination to define a locus and then sequencing genes. Our formally identical approach first sequences all the genes and then seeks cosegregation with the trait. Mutagenized lines lacking obvious phenotypic alterations are available for an extension of this approach: mapping with a known marker set in a line that is phenotypically identical to starting material for EMS mutant generation.

  14. Dynamics of cell proliferation in the adult dentate gyrus of two inbred strains of mice

    Science.gov (United States)

    Hayes, N. L.; Nowakowski, R. S.

    2002-01-01

    The output potential of proliferating populations in either the developing or the adult nervous system is critically dependent on the length of the cell cycle (T(c)) and the size of the proliferating population. We developed a new approach for analyzing the cell cycle, the 'Saturate and Survive Method' (SSM), that also reveals the dynamic behaviors in the proliferative population and estimates of the size of the proliferating population. We used this method to analyze the proliferating population of the adult dentate gyrus in 60 day old mice of two inbred strains, C57BL/6J and BALB/cByJ. The results show that the number of cells labeled by exposure to BUdR changes dramatically with time as a function of the number of proliferating cells in the population, the length of the S-phase, cell division, the length of the cell cycle, dilution of the S-phase label, and cell death. The major difference between C57BL/6J and BALB/cByJ mice is the size of the proliferating population, which differs by a factor of two; the lengths of the cell cycle and the S-phase and the probability that a newly produced cell will die within the first 10 days do not differ in these two strains. This indicates that genetic regulation of the size of the proliferating population is independent of the genetic regulation of cell death among those newly produced cells. The dynamic changes in the number of labeled cells as revealed by the SSM protocol also indicate that neither single nor repeated daily injections of BUdR accurately measure 'proliferation.'.

  15. Causes and consequences of chromatin variation between inbred mice.

    Directory of Open Access Journals (Sweden)

    Mona Hosseini

    2013-06-01

    Full Text Available Variation at regulatory elements, identified through hypersensitivity to digestion by DNase I, is believed to contribute to variation in complex traits, but the extent and consequences of this variation are poorly characterized. Analysis of terminally differentiated erythroblasts in eight inbred strains of mice identified reproducible variation at approximately 6% of DNase I hypersensitive sites (DHS. Only 30% of such variable DHS contain a sequence variant predictive of site variation. Nevertheless, sequence variants within variable DHS are more likely to be associated with complex traits than those in non-variant DHS, and variants associated with complex traits preferentially occur in variable DHS. Changes at a small proportion (less than 10% of variable DHS are associated with changes in nearby transcriptional activity. Our results show that whilst DNA sequence variation is not the major determinant of variation in open chromatin, where such variants exist they are likely to be causal for complex traits.

  16. Testing Sunflower Inbred Lines for Tolerance to Phoma Black Stem

    Directory of Open Access Journals (Sweden)

    Boško Dedić

    2012-01-01

    Full Text Available Phoma black stem is caused by a widespread pathogen Phoma macdonaldii Boerema.The disease occurs regularly, causing damage by early defoliation and premature ripening.Complete resistance of sunflower to this disease has never been found, but there arereports of differences in response by different genotypes. Fifty-four new inbred lines weretested in our trials conducted at the Rimski Šančevi experimental field. Plants in one trialwere non-irrigated, and irrigated in another. Sunflower plants were artificially inoculatedwith mycelial plugs in the bud stage. The length of stem lesions was measured and comparedusing an analysis of variance. Disease intensity was generally more severe in the nonirrigatedfield. There were significant differences in tolerance to Phoma black stem amongthe tested lines in both trials. The percentage of tolerant genotypes was 1.8%.

  17. Quantitative trait loci mapping for flowering time in a switchgrass pseudo-F2 population

    Science.gov (United States)

    Flowering is an important developmental event in switchgrass (Panicum virgatum) because the onset of flowering causes the cessation of vegetative growth and biomass accumulation. The objective of this study was to generate a linkage map using single nucleotide polymorphism (SNP) markers to identify ...

  18. Genetic linkage mapping in an F2 perennial ryegrass population using DArT markers

    Czech Academy of Sciences Publication Activity Database

    Tomaszewski, C.; Byrne, S. L.; Foito, A.; Kildea, S.; Kopecký, David; Doležel, Jaroslav; Heslop-Harrison, J. S.; Stewart, D.; Barth, S.

    2012-01-01

    Roč. 131, č. 2 (2012), s. 345-349 ISSN 0179-9541 Institutional research plan: CEZ:AV0Z50380511 Keywords : Lolium perenne * perennial ryegrass * genetic map Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.175, year: 2012

  19. Effective selection criteria for screening drought tolerant recombinant inbred lines of sunflower

    Directory of Open Access Journals (Sweden)

    Abdi Nishtman

    2013-01-01

    Full Text Available In this study, seventy two sunflower recombinant inbred lines were tested for their yielding ability under both water-stressed and well-watered states. The inbred lines were evaluated in a rectangular 8´9 lattice design with two replications in both well-watered and water-stressed conditions, separately. Eight drought tolerance indices including stability tolerance index (STI, mean productivity (MP, geometric mean productivity (GMP, harmonic mean (HM, stress susceptibility index (SSI, tolerance index (TOL, yield index (YI and yield stability index (YSI were calculated based on grain yield for every genotype. Results showed the highest values of mean productivity (MP index, geometric mean productivity (GMP, yield index (YI, harmonic mean (HM and stress tolerance index (STI indices for ‘C134a’ inbred line and least values of stress susceptibility index (SSI and tolerance (TOL for C61 inbred line. According to correlation of indices with yield performance under both drought stress and non-stress states and principle component analysis, indices including HM, MP, GMP and STI could properly distinguish drought tolerant sunflower inbred lines with high yield performance under both states. Cluster analysis of inbred lines using Ys, Yp and eight indices, categorized them into four groups including 19, 6, 26 and 19 inbred lines.

  20. Demarcation of informative chromosomes in tropical sweet corn inbred lines using microsatellite DNA markers

    Directory of Open Access Journals (Sweden)

    Pedram Kashiani

    2012-01-01

    Full Text Available A study of genetic variation among 10 pairs of chromosomes extracted from 13 tropical sweet corn inbred lines, using 99 microsatellite markers, revealed a wide range of genetic diversity. Allelic richness and the number of effective alleles per chromosome ranged from 2.78 to 4.33 and 1.96 to 3.47, respectively, with respective mean values of 3.62 and 2.73. According to the Shannon's information index (I and Nei's gene diversity coefficient (Nei, Chromosome 10 was the most informative chromosome (I = 1.311 and Nei = 0.703, while Chromosome 2 possessed the least (I = 0.762 and Nei = 0.456. Based on linkage disequilibrium (LD measurements for loci less than 50 cM apart on the same chromosome, all loci on Chromosomes 1, 6 and 7 were in equilibrium. Even so, there was a high proportion of genetic variation in Chromosomes 4, 5, 8, 9 and 10, thereby revealing their appropriateness for use in the genetic diversity investigations among tropical sweet corn lines. Chromosome 4, with the highest number of loci in linkage disequilibrium, was considered the best for marker-phenotype association and QTL mapping, followed by Chromosomes 5, 8, 9 and 10.

  1. Genomewide mapping reveals a combination of different genetic ...

    Indian Academy of Sciences (India)

    These methodologies could not investigate all kinds of genetic effects, especially epistatic effects, simultaneously on the whole genome. In this study, with a statistical method for mapping epistatic QTL associated with heterosis using the recombinant inbred line (RIL)-based NCIII design, we conducted QTL mapping for nine ...

  2. China Dimensions Data Collection: China County-Level Data on Population (Census) and Agriculture, Keyed to 1:1M GIS Map

    Data.gov (United States)

    National Aeronautics and Space Administration — China County-Level Data on Population (Census) and Agriculture, Keyed To 1:1M GIS Map consists of census, agricultural economic, and boundary data for the...

  3. Marker-assisted breeding for introgression of opaque-2 allele into elite maize inbred line BML-7.

    Science.gov (United States)

    Krishna, M S R; Sokka Reddy, S; Satyanarayana, Sadam D V

    2017-07-01

    Improvement of quality protein maize (QPM) along with high content of lysine and tryptophan had foremost importance in maize breeding program. The efficient and easiest way of developing QPM hybrids was by backcross breeding in marker aided selection. Hence, the present investigation aimed at conversion of elite maize inbred line BML-7 into QPM line. CML-186 was identified to be a donor variety as it revealed high-quality polymorphism with BML-7 for opaque-2 gene specific marker umc1066. Non-QPM inbred line BML-7 was crossed with QPM donor CML-186 and produced F 1 followed by the development of BC 1 F 1 and BC 2 F 1 population. Foreground selection was carried out with umc1066 in F 1 , and selected plants were used for BC 1 F 1 and BC 2 F 1 populations. Two hundred plants were screened in both BC 1 F 1 and BC 2 F 1 population with umc1066 for foreground selection amino acid modifiers. Foreground selected plants for both opaque-2 and amino acid modifiers were screened for background selection for BML-7 genome. Recurrent parent genome (RPG) was calculated for BC 2 F 1 population plants. Two plants have shown with RPG 90-93% in two generation with back cross population. Two BC 2 F 2 populations resulted from marker recognized BC 2 F 1 individuals subjected toward foreground selection followed by tryptophan estimation. The tryptophan and lysine concentration was improved in all the plants. BC 2 F 2 lines developed from hard endosperm kernels were selfed for BC 2 F 2 lines and finest line was selected to illustrate the QPM version of BML-7, with 0.97% of tryptophan and 4.04% of lysine concentration in protein. Therefore, the QPM version of BML-7 line can be used for the development of single cross hybrid QPM maize version.

  4. Deciphering Natural Allelic Variation in Switchgrass for Biomass Yield and Quality Using a Nested Association Mapping Population

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Malay C. [The Samuel Roberts Noble Foundation, Inc., Ardmore, OK (United States). Forage Improvement Division (FID); Brummer, E. Charles [The Samuel Roberts Noble Foundation, Inc., Ardmore, OK (United States); Kaeppler, Shawn [Univ. of Wisconsin, Madison, WI (United States); Bhandari, Hem S. [Univ. of Tennessee, Knoxville, TN (United States)

    2016-10-28

    Switchgrass (Panicum virgatum L.) is a C4 grass with high biomass yield potential and a model species for bioenergy feedstock development. Understanding the genetic basis of quantitative traits is essential to facilitate genome-enabled breeding programs. The nested association mapping (NAM) analysis combines the best features of both bi-parental and association analyses and can provide high power and high resolution in QTL detection and will ensure significant improvements in biomass yield and quality. To develop a NAM population of switchgrass, 15 highly diverse genotypes with specific characteristics were selected from a diversity panel and crossed to a recurrent parent, AP13, a genotype selected for whole genome sequencing and parent of a mapping population. Ten genotypes from each of the 15 F1 families were then chain crossed. Progenies form each family were randomly selected to develop the NAM population. The switchgrass NAM population consists of a total of 2000 genotypes from 15 families. All the progenies, founder parents, F1 parents (n=2350) were evaluated in replicated field trials at Ardmore, OK and Knoxville, TN. Phenotypic data on plant height, tillering ability, regrowth, flowering time, and biomass yield were collected. Dried biomass samples were also analyzed using prediction equations of NIRS at the Noble Foundation and for lignin content, S/G ratio, and sugar release characteristics at the NREL. Genomic shotgun sequencing of 15 switchgrass NAM founder parental genomes at JGI produced 28-66 Gb high-quality sequence data. Alignment of these sequences with the reference genome, AP13 (v3.0), revealed that up to 99% of the genomic sequences mapped to the reference genome. A total of 2,149 individuals from NAM populations were sequenced by exome capture and two sets of 15 SNP matrices (one for each family) were generated. QTL associated with important traits have been identified and verified in breeding populations. The QTL detected and their associated

  5. A comparison of bivariate and univariate QTL mapping in livestock populations

    Directory of Open Access Journals (Sweden)

    Sorensen Daniel

    2003-11-01

    Full Text Available Abstract This study presents a multivariate, variance component-based QTL mapping model implemented via restricted maximum likelihood (REML. The method was applied to investigate bivariate and univariate QTL mapping analyses, using simulated data. Specifically, we report results on the statistical power to detect a QTL and on the precision of parameter estimates using univariate and bivariate approaches. The model and methodology were also applied to study the effectiveness of partitioning the overall genetic correlation between two traits into a component due to many genes of small effect, and one due to the QTL. It is shown that when the QTL has a pleiotropic effect on two traits, a bivariate analysis leads to a higher statistical power of detecting the QTL and to a more precise estimate of the QTL's map position, in particular in the case when the QTL has a small effect on the trait. The increase in power is most marked in cases where the contributions of the QTL and of the polygenic components to the genetic correlation have opposite signs. The bivariate REML analysis can successfully partition the two components contributing to the genetic correlation between traits.

  6. Disaggregating census data for population mapping using random forests with remotely-sensed and ancillary data.

    Science.gov (United States)

    Stevens, Forrest R; Gaughan, Andrea E; Linard, Catherine; Tatem, Andrew J

    2015-01-01

    High resolution, contemporary data on human population distributions are vital for measuring impacts of population growth, monitoring human-environment interactions and for planning and policy development. Many methods are used to disaggregate census data and predict population densities for finer scale, gridded population data sets. We present a new semi-automated dasymetric modeling approach that incorporates detailed census and ancillary data in a flexible, "Random Forest" estimation technique. We outline the combination of widely available, remotely-sensed and geospatial data that contribute to the modeled dasymetric weights and then use the Random Forest model to generate a gridded prediction of population density at ~100 m spatial resolution. This prediction layer is then used as the weighting surface to perform dasymetric redistribution of the census counts at a country level. As a case study we compare the new algorithm and its products for three countries (Vietnam, Cambodia, and Kenya) with other common gridded population data production methodologies. We discuss the advantages of the new method and increases over the accuracy and flexibility of those previous approaches. Finally, we outline how this algorithm will be extended to provide freely-available gridded population data sets for Africa, Asia and Latin America.

  7. Disaggregating census data for population mapping using random forests with remotely-sensed and ancillary data.

    Directory of Open Access Journals (Sweden)

    Forrest R Stevens

    Full Text Available High resolution, contemporary data on human population distributions are vital for measuring impacts of population growth, monitoring human-environment interactions and for planning and policy development. Many methods are used to disaggregate census data and predict population densities for finer scale, gridded population data sets. We present a new semi-automated dasymetric modeling approach that incorporates detailed census and ancillary data in a flexible, "Random Forest" estimation technique. We outline the combination of widely available, remotely-sensed and geospatial data that contribute to the modeled dasymetric weights and then use the Random Forest model to generate a gridded prediction of population density at ~100 m spatial resolution. This prediction layer is then used as the weighting surface to perform dasymetric redistribution of the census counts at a country level. As a case study we compare the new algorithm and its products for three countries (Vietnam, Cambodia, and Kenya with other common gridded population data production methodologies. We discuss the advantages of the new method and increases over the accuracy and flexibility of those previous approaches. Finally, we outline how this algorithm will be extended to provide freely-available gridded population data sets for Africa, Asia and Latin America.

  8. Haplotypes at the Tas2r locus on distal chromosome 6 vary with quinine taste sensitivity in inbred mice

    Directory of Open Access Journals (Sweden)

    Munger Steven D

    2005-06-01

    Full Text Available Abstract Background The detection of bitter-tasting compounds by the gustatory system is thought to alert animals to the presence of potentially toxic food. Some, if not all, bitter stimuli activate specific taste receptors, the T2Rs, which are expressed in subsets of taste receptor cells on the tongue and palate. However, there is evidence for both receptor-dependent and -independent transduction mechanisms for a number of bitter stimuli, including quinine hydrochloride (QHCl and denatonium benzoate (DB. Results We used brief-access behavioral taste testing of BXD/Ty recombinant inbred (RI mouse strains to map the major quantitative trait locus (QTL for taste sensitivity to QHCl. This QTL is restricted to a ~5 Mb interval on chromosome 6 that includes 24 genes encoding T2Rs (Tas2rs. Tas2rs at this locus display in total 307 coding region single nucleotide polymorphisms (SNPs between the two BXD/Ty RI parental strains, C57BL/6J (quinine-sensitive and DBA/2J (quinine insensitive; approximately 50% of these mutations are silent. Individual RI lines contain exclusively either C57BL/6J or DBA/2J Tas2r alleles at this locus, and RI lines containing C57BL/6J Tas2r alleles are more sensitive to QHCl than are lines containing DBA/2J alleles. Thus, the entire Tas2r cluster comprises a large haplotype that correlates with quinine taster status. Conclusion These studies, the first using a taste-salient assay to map the major QTL for quinine taste, indicate that a T2R-dependent transduction cascade is responsible for the majority of strain variance in quinine taste sensitivity. Furthermore, the large number of polymorphisms within coding exons of the Tas2r cluster, coupled with evidence that inbred strains exhibit largely similar bitter taste phenotypes, suggest that T2R receptors are quite tolerant to variation.

  9. Maps, Models and Registers: the Historical Geography of the Population of England

    OpenAIRE

    Kearns, Gerry

    2000-01-01

    In most European countries, regular censuses of population together with vital registration allow the historical geography of population changes to be studied with some confidence for the nineteenth and twentieth centuries. For earlier periods, we must rely in the main upon parish registers. Henry showed that these records of vital events could be used to build up pictures of families allowing many demographic measures to be calculated. Most English registers do not include as ...

  10. A Population of Deletion Mutants and an Integrated Mapping and Exome-seq Pipeline for Gene Discovery in Maize

    Science.gov (United States)

    Jia, Shangang; Li, Aixia; Morton, Kyla; Avoles-Kianian, Penny; Kianian, Shahryar F.; Zhang, Chi; Holding, David

    2016-01-01

    To better understand maize endosperm filling and maturation, we used γ-irradiation of the B73 maize reference line to generate mutants with opaque endosperm and reduced kernel fill phenotypes, and created a population of 1788 lines including 39 Mo17 × F2s showing stable, segregating, and viable kernel phenotypes. For molecular characterization of the mutants, we developed a novel functional genomics platform that combined bulked segregant RNA and exome sequencing (BSREx-seq) to map causative mutations and identify candidate genes within mapping intervals. To exemplify the utility of the mutants and provide proof-of-concept for the bioinformatics platform, we present detailed characterization of line 937, an opaque mutant harboring a 6203 bp in-frame deletion covering six exons within the Opaque-1 gene. In addition, we describe mutant line 146 which contains a 4.8 kb intragene deletion within the Sugary-1 gene and line 916 in which an 8.6 kb deletion knocks out a Cyclin A2 gene. The publically available algorithm developed in this work improves the identification of causative deletions and its corresponding gaps within mapping peaks. This study demonstrates the utility of γ-irradiation for forward genetics in large nondense genomes such as maize since deletions often affect single genes. Furthermore, we show how this classical mutagenesis method becomes applicable for functional genomics when combined with state-of-the-art genomics tools. PMID:27261000

  11. Whole exome sequencing of wild-derived inbred strains of mice improves power to link phenotype and genotype.

    Science.gov (United States)

    Chang, Peter L; Kopania, Emily; Keeble, Sara; Sarver, Brice A J; Larson, Erica; Orth, Annie; Belkhir, Khalid; Boursot, Pierre; Bonhomme, François; Good, Jeffrey M; Dean, Matthew D

    2017-10-01

    The house mouse is a powerful model to dissect the genetic basis of phenotypic variation, and serves as a model to study human diseases. Despite a wealth of discoveries, most classical laboratory strains have captured only a small fraction of genetic variation known to segregate in their wild progenitors, and existing strains are often related to each other in complex ways. Inbred strains of mice independently derived from natural populations have the potential to increase power in genetic studies with the addition of novel genetic variation. Here, we perform exome-enrichment and high-throughput sequencing (~8× coverage) of 26 wild-derived strains known in the mouse research community as the "Montpellier strains." We identified 1.46 million SNPs in our dataset, approximately 19% of which have not been detected from other inbred strains. This novel genetic variation is expected to contribute to phenotypic variation, as they include 18,496 nonsynonymous variants and 262 early stop codons. Simulations demonstrate that the higher density of genetic variation in the Montpellier strains provides increased power for quantitative genetic studies. Inasmuch as the power to connect genotype to phenotype depends on genetic variation, it is important to incorporate these additional genetic strains into future research programs.

  12. An improved procedure for integrated behavioral z-scoring illustrated with modified Hole Board behavior of male inbred laboratory mice.

    Science.gov (United States)

    Labots, M Maaike; Laarakker, M C Marijke; Schetters, D Dustin; Arndt, S S Saskia; van Lith, H A Hein

    2018-01-01

    Guilloux et al. introduced: integrated behavioral z-scoring, a method for behavioral phenotyping of mice. Using this method multiple ethological variables can be combined to show an overall description of a certain behavioral dimension or motivational system. However, a problem may occur when the control group used for the calculation has a standard deviation of zero or when no control group is present to act as a reference group. In order to solve these problems, an improved procedure is suggested: taking the pooled data as reference. For this purpose a behavioral study with male mice from three inbred strains was carried out. The integrated behavioral z-scoring methodology was applied, thereby taking five different reference group options. The outcome regarding statistical significance and practical importance was compared. Significant effects and effect sizes were influenced by the choice of the reference group. In some cases it was impossible to use a certain population and condition, because one or more behavioral variables in question had a standard deviation of zero. Based on the improved method, male mice from the three inbred strains differed regarding activity and anxiety. Taking the method described by Guilloux et al. as basis, the present procedure improved the generalizability to all types of experimental designs in animal behavioral research. To solve the aforementioned problems and to avoid getting the diagnosis of data manipulation, the pooled data (combining the data from all experimental groups in a study) as reference option is recommended. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Rapid creation of Arabidopsis doubled haploid lines for quantitative trait locus mapping.

    Science.gov (United States)

    Seymour, Danelle K; Filiault, Daniele L; Henry, Isabelle M; Monson-Miller, Jennifer; Ravi, Maruthachalam; Pang, Andy; Comai, Luca; Chan, Simon W L; Maloof, Julin N

    2012-03-13

    Quantitative trait loci (QTL) mapping is a powerful tool for investigating the genetic basis of natural variation. QTL can be mapped using a number of different population designs, but recombinant inbred lines (RILs) are among the most effective. Unfortunately, homozygous RIL populations are time consuming to construct, typically requiring at least six generations of selfing starting from a heterozygous F(1). Haploid plants produced from an F(1) combine the two parental genomes and have only one allele at every locus. Converting these sterile haploids into fertile diploids (termed "doubled haploids," DHs) produces immortal homozygous lines in only two steps. Here we describe a unique technique for rapidly creating recombinant doubled haploid populations in Arabidopsis thaliana: centromere-mediated genome elimination. We generated a population of 238 doubled haploid lines that combine two parental genomes and genotyped them by reduced representation Illumina sequencing. The recombination rate and parental allele frequencies in our population are similar to those found in existing RIL sets. We phenotyped this population for traits related to flowering time and for petiole length and successfully mapped QTL controlling each trait. Our work demonstrates that doubled haploid populations offer a rapid, easy alternative to RILs for Arabidopsis genetic analysis.

  14. Histocompatible chicken inbred lines: homogeneities in the major histocompatibility complex antigens of the GSP, GSN/1, PNP/DO and BM-C inbred lines assessed by hemagglutination, mixed lymphocyte reaction and skin transplantation.

    Science.gov (United States)

    Valdez, Marcos B; Mizutani, Makoto; Fujiwara, Akira; Yazawa, Hajime; Yamagata, Takahiro; Shimada, Kiyoshi; Namikawa, Takao

    2007-10-01

    Chicken inbred lines of the GSP, GSN/1, PNP/DO and BM-C have been established by selection of a specific allele at the B blood group locus (MHC B-G region) and other polymorphic loci through pedigree mating. To extend the potential of these inbred lines as experimental animals in Aves, we assessed the antigenic homogeneities of the MHC antigens by three immunological methods. Antigenic variations of red blood cells (RBCs) were surveyed in the inbred lines and a random-bred line (NG) derived from the Nagoya breed by using ten kinds of intact antisera produced in the inbred line of chickens against RBCs of a red junglefowl and hybrids. In the hemagglutination test, no individual variations were found within the inbred line at all, while all the ten antisera detected highly heterogeneous reactions in individuals of the NG. The reciprocal one-way mixed lymphocyte reactions gave constantly higher stimulation responses (PGSP and GSN/1 inbred lines both having the B(21) allele. In reciprocal skin transplantation, the transplanted skingrafts within the inbred line and between individuals from the GSP and GSN/1 inbred lines survived more than 100 days, while all the skingrafts showed signs of rejection within 7 days among the inbred lines having different B alleles. The results obtained by the three practical methods coincidentally indicated that the individuals in the respective four inbred lines were histocompatible, and further, that the GSP and GSN/1 individuals were histocompatible.

  15. The K-INBRE symposium: a 10-institution collaboration to improve undergraduate education.

    Science.gov (United States)

    Velasquez, Sarah E; Abraham, K; Burnett, Tim G; Chapin, Bridgett; Hendry, William J; Leung, Sam; Madden, Michael E; Rider, Virginia; Stanford, John A; Ward, Robert E; Chapes, Stephen K

    2018-03-01

    The Kansas-IDeA Network of Biomedical Research Excellence (K-INBRE) is an infrastructure-building program funded by the National Institute of General Medical Sciences. Undergraduate education, through undergraduate research, is a key component of the program. The K-INBRE network includes 10 higher education institutions in Kansas and northern Oklahoma, with over 1,000 student participants in 16 yr. Since 2003, the K-INBRE has held an annual state-wide research symposium that includes national and regional speakers and provides a forum for undergraduates to give platform and poster presentations. The symposium is well attended by K-INBRE participants and has grown to a size of over 300 participants per year from all 10 K-INBRE schools. Two surveys were distributed to students and mentors to assess the impact of the symposium on student learning. Surveys (153) were distributed to students who participated in K-INBRE from 2013 through 2015 with a 51% response rate. Mentors were surveyed with a response of 111 surveys out of 161. Survey results indicate that students and mentors alike find the symposium to be beneficial and enriching of the student experience. Almost 80% of student respondents indicated that their participation in the symposium fostered appreciation of research. In short, the K-INBRE symposium provides a unique opportunity for students to gain experience in collecting, preparing, and communicating research in a professional environment. The collaborative experience of the annual K-INBRE symposium, the impact it has on student learning, and how it has influenced the research culture at our 10 institutions will be described.

  16. Mapping long-term spatial trends of the Taimyr wild reindeer population

    Directory of Open Access Journals (Sweden)

    Andrey N. Petrov

    2013-03-01

    Full Text Available This report presents preliminary results of mapping and analyzing wild reindeer spatial dynamics in Taimyr, Russia. We collected, spatially referenced, and systematized comprehensive aerial and land survey information spanning from 1969 to 2003, which is the most complete long-term data available about a wild reindeer herd in Eurasia. The report introduces some of the mapping products and presents a summary of our observations on spatiotemporal changes in reindeer distribution and migration. Using these data and new digital products in the GIS (Geographic Information Systems environment, we were able to observe the long-term shift of the Taimyr Reindeer Herd's summer, winter, and calving areas to the east and south with a simultaneous expansion of the habitat. We identified and confirmed locations of large reindeer concentrations (herds seasonally formed throughout the study period. Using the most recent summer survey data (2009 we also were able to confirm the existence of two major migration flows in the fall: eastern (most reindeer and western.

  17. Evaluation of Lentil Recombinant Inbred Lines using Drought Tolerance Indices

    Directory of Open Access Journals (Sweden)

    Mohammad Hassan Rahimi

    2017-04-01

    Full Text Available To identify drought tolerant lines among 168 recombinant inbred lines derived from a cross between Hindi variety of L3685 (high yielding, erect type and early growth as female parent and Iranian variety of Qazvin (with prostrate growth and late growth as male parent, two experiments were conducted in randomized complete block design with three replications under non-stress and drought stress conditions at the experimental Field of Shahrekord University in 2013. Results of combined analysis of variance showed that there were significant differences among lines under study in both experimental conditions in terms of grain yield (P≤0.01. Significant interaction of line×conditions revealed that lines responded differently to drought stress based on grain yield. Results also indicates that lines 160, 125 and 129 were promising lines under both conditions in terms of grain yield. Positive and significant correlation between tolerance indices and grain yield under stress and non-stress conditions indicated that the STI, MP, HARM and GMP indices may identify promising from non promising lines. Based on the above criteria, lines 160, 125, 48, 103 and 129 were recognized as drought tolerant lines. According to the results of principal components analysis, the first and second components determined 97.8% of the total variations among genotypes under study for drought resistance indices. The distribution of lines in the biplot showed genetic variations to the drought stress and thus lines 160, 125, 48, 129 and 103 were identified as high yielders under drought stress condition.

  18. QTL mapping of inbreeding-related cold sensitivity and conditional lethality in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Vermeulen, Corneel J.; Bijlsma, R.; Loeschcke, Volker

    2008-01-01

    of inbreeding-related and conditionally expressed lethality in Drosophila melanogaster. The lethal effect was triggered by exposure to a cold shock. We used a North Carolina crossing Design 3 to establish the mapping population, as well as to estimate the average dominance ratio and heritability. We found two......Inbreeding depression is a central theme within genetics, and is of specific interest for researchers within evolutionary and conservation genetics and animal and plant breeding. Inbreeding effects are thought to be caused by the joint expression of conditional and unconditional deleterious alleles....... Whenever the expression of deleterious alleles is conditional, this can result in extreme environmental sensitivity in certain inbred lineages. Analysis of conditional lethal effects can reveal some of the loci that are sensitive to inbreeding. We performed a QTL (quantitative trait locus) mapping study...

  19. Fine-mapping of lipid regions in global populations discovers ethnic-specific signals and refines previously identified lipid loci

    Science.gov (United States)

    Zubair, Niha; Luis Ambite, Jose; Bush, William S.; Kichaev, Gleb; Lu, Yingchang; Manichaikul, Ani; Sheu, Wayne H-H.; Absher, Devin; Assimes, Themistocles L.; Bielinski, Suzette J.; Bottinger, Erwin P.; Buzkova, Petra; Chuang, Lee-Ming; Chung, Ren-Hua; Cochran, Barbara; Dumitrescu, Logan; Gottesman, Omri; Haessler, Jeffrey W.; Haiman, Christopher; Heiss, Gerardo; Hsiung, Chao A.; Hung, Yi-Jen; Hwu, Chii-Min; Juang, Jyh-Ming J.; Le Marchand, Loic; Lee, I-Te; Lee, Wen-Jane; Lin, Li-An; Lin, Danyu; Lin, Shih-Yi; Mackey, Rachel H.; Martin, Lisa W.; Pasaniuc, Bogdan; Peters, Ulrike; Predazzi, Irene; Quertermous, Thomas; Reiner, Alex P.; Robinson, Jennifer; Rotter, Jerome I.; Ryckman, Kelli K.; Schreiner, Pamela J.; Stahl, Eli; Tao, Ran; Tsai, Michael Y.; Waite, Lindsay L.; Wang, Tzung-Dau; Buyske, Steven; Ida Chen, Yii-Der; Cheng, Iona; Crawford, Dana C.; Loos, Ruth J.F.; Rich, Stephen S.; Fornage, Myriam; North, Kari E.; Kooperberg, Charles; Carty, Cara L.

    2016-01-01

    Abstract Genome-wide association studies have identified over 150 loci associated with lipid traits, however, no large-scale studies exist for Hispanics and other minority populations. Additionally, the genetic architecture of lipid-influencing loci remains largely unknown. We performed one of the most racially/ethnically diverse fine-mapping genetic studies of HDL-C, LDL-C, and triglycerides to-date using SNPs on the MetaboChip array on 54,119 individuals: 21,304 African Americans, 19,829 Hispanic Americans, 12,456 Asians, and 530 American Indians. The majority of signals found in these groups generalize to European Americans. While we uncovered signals unique to racial/ethnic populations, we also observed systematically consistent lipid associations across these groups. In African Americans, we identified three novel signals associated with HDL-C (LPL, APOA5, LCAT) and two associated with LDL-C (ABCG8, DHODH). In addition, using this population, we refined the location for 16 out of the 58 known MetaboChip lipid loci. These results can guide tailored screening efforts, reveal population-specific responses to lipid-lowering medications, and aid in the development of new targeted drug therapies. PMID:28426890

  20. A simple method for combining genetic mapping data from multiple crosses and experimental designs.

    Directory of Open Access Journals (Sweden)

    Jeremy L Peirce

    Full Text Available BACKGROUND: Over the past decade many linkage studies have defined chromosomal intervals containing polymorphisms that modulate a variety of traits. Many phenotypes are now associated with enough mapping data that meta-analysis could help refine locations of known QTLs and detect many novel QTLs. METHODOLOGY/PRINCIPAL FINDINGS: We describe a simple approach to combining QTL mapping results for multiple studies and demonstrate its utility using two hippocampus weight loci. Using data taken from two populations, a recombinant inbred strain set and an advanced intercross population we demonstrate considerable improvements in significance and resolution for both loci. 1-LOD support intervals were improved 51% for Hipp1a and 37% for Hipp9a. We first generate locus-wise permuted P-values for association with the phenotype from multiple maps, which can be done using a permutation method appropriate to each population. These results are then assigned to defined physical positions by interpolation between markers with known physical and genetic positions. We then use Fisher's combination test to combine position-by-position probabilities among experiments. Finally, we calculate genome-wide combined P-values by generating locus-specific P-values for each permuted map for each experiment. These permuted maps are then sampled with replacement and combined. The distribution of best locus-specific P-values for each combined map is the null distribution of genome-wide adjusted P-values. CONCLUSIONS/SIGNIFICANCE: Our approach is applicable to a wide variety of segregating and non-segregating mapping populations, facilitates rapid refinement of physical QTL position, is complementary to other QTL fine mapping methods, and provides an appropriate genome-wide criterion of significance for combined mapping results.

  1. Genome mapping in F 1 population of crossbred Italia and Mercan ...

    African Journals Online (AJOL)

    ... and Mercan), 60 F1 (Italia × Mercan population) and two reference grape cultivar (Cabarnet Sauvignon and Merlot), successfully amplifying 112 markers. When the resistance traits to fungal diseases were analyzed during the study, no markers related with resistance to Botrytis cinerea and downy mildew could be found.

  2. Mapping the genetic diversity of HLA haplotypes in the Japanese populations

    Science.gov (United States)

    Saw, Woei-Yuh; Liu, Xuanyao; Khor, Chiea-Chuen; Takeuchi, Fumihiko; Katsuya, Tomohiro; Kimura, Ryosuke; Nabika, Toru; Ohkubo, Takayoshi; Tabara, Yasuharu; Yamamoto, Ken; Yokota, Mitsuhiro; Akiyama, Koichi; Asano, Hiroyuki; Asayama, Kei; Haga, Toshikazu; Hara, Azusa; Hirose, Takuo; Hosaka, Miki; Ichihara, Sahoko; Imai, Yutaka; Inoue, Ryusuke; Ishiguro, Aya; Isomura, Minoru; Isono, Masato; Kamide, Kei; Kato, Norihiro; Katsuya, Tomohiro; Kikuya, Masahiro; Kohara, Katsuhiko; Matsubara, Tatsuaki; Matsuda, Ayako; Metoki, Hirohito; Miki, Tetsuro; Murakami, Keiko; Nabika, Toru; Nakatochi, Masahiro; Ogihara, Toshio; Ohnaka, Keizo; Ohkubo, Takayoshi; Rakugi, Hiromi; Satoh, Michihiro; Shiwaku, Kunihiro; Sugimoto, Ken; Tabara, Yasuharu; Takami, Yoichi; Takayanagi, Ryoichi; Takeuchi, Fumihiko; Tsubota-Utsugi, Megumi; Yamamoto, Ken; Yamamoto, Koichi; Yamasaki, Masayuki; Yasui, Daisaku; Yokota, Mitsuhiro; Teo, Yik-Ying; Kato, Norihiro

    2015-01-01

    Japan has often been viewed as an Asian country that possesses a genetically homogenous community. The basis for partitioning the country into prefectures has largely been geographical, although cultural and linguistic differences still exist between some of the districts/prefectures, especially between Okinawa and the mainland prefectures. The Major Histocompatibility Complex (MHC) region has consistently emerged as the most polymorphic region in the human genome, harbouring numerous biologically important variants; nevertheless the presence of population-specific long haplotypes hinders the imputation of SNPs and classical HLA alleles. Here, we examined the extent of genetic variation at the MHC between eight Japanese populations sampled from Okinawa, and six other prefectures located in or close to the mainland of Japan, specifically focusing at the haplotypes observed within each population, and what the impact of any variation has on imputation. Our results indicated that Okinawa was genetically farther to the mainland Japanese than were Gujarati Indians from Tamil Indians, while the mainland Japanese from six prefectures were more homogeneous than between northern and southern Han Chinese. The distribution of haplotypes across Japan was similar, although imputation was most accurate for Okinawa and several mainland prefectures when population-specific panels were used as reference. PMID:26648100

  3. Absence of evidence for MHC-dependent mate selection within HapMap populations.

    Directory of Open Access Journals (Sweden)

    Adnan Derti

    2010-04-01

    Full Text Available The major histocompatibility complex (MHC of immunity genes has been reported to influence mate choice in vertebrates, and a recent study presented genetic evidence for this effect in humans. Specifically, greater dissimilarity at the MHC locus was reported for European-American mates (parents in HapMap Phase 2 trios than for non-mates. Here we show that the results depend on a few extreme data points, are not robust to conservative changes in the analysis procedure, and cannot be reproduced in an equivalent but independent set of European-American mates. Although some evidence suggests an avoidance of extreme MHC similarity between mates, rather than a preference for dissimilarity, limited sample sizes preclude a rigorous investigation. In summary, fine-scale molecular-genetic data do not conclusively support the hypothesis that mate selection in humans is influenced by the MHC locus.

  4. Romanian maize (Zea mays inbred lines as a source of genetic diversity in SE Europe, and their potential in future breeding efforts.

    Directory of Open Access Journals (Sweden)

    Dana Şuteu

    Full Text Available Maize has always been under constant human selection ever since it had been domesticated. Intensive breeding programs that resulted in the massive use of hybrids nowadays have started in the 60s. That brought significant yield increases but reduced the genetic diversity at the same time. Consequently, breeders and researchers alike turned their attention to national germplasm collections established decades ago in many countries, as they may hold allelic variations that could prove useful for future improvements. These collections are mainly composed of inbred lines originating from well-adapted local open pollinated varieties. However, there is an overall lack of data in the literature about the genetic diversity of maize in SE Europe, and its potential for future breeding efforts. There are no data, whatsoever, on the nutritional quality of the grain, primarily dictated by the zein proteins. We therefore sought to use the Romanian maize germplasm as an entry point in understanding the molecular make-up of maize in this part of Europe. By using 80 SSR markers, evenly spread throughout the genome, on 82 inbred lines from various parts of the country, we were able to decipher population structure and the existing relationships between those and the eight international standards used, including the reference sequenced genome B73. Corroborating molecular data with a standardized morphological, physiological, and biochemical characterization of all 90 inbred lines, this is the first comprehensive such study on the existing SE European maize germplasm. The inbred lines we present here are an important addition to the ever-shrinking gene pool that the breeding programs are faced-with, because of the allelic richness they hold. They may serve as parental lines in crosses that will lead to new hybrids, characterized by a high level of heterosis, nationwide and beyond, due to their existing relationship with the international germplasm.

  5. A high density consensus map of rye (Secale cereale L. based on DArT markers.

    Directory of Open Access Journals (Sweden)

    Paweł Milczarski

    Full Text Available BACKGROUND: Rye (Secale cereale L. is an economically important crop, exhibiting unique features such as outstanding resistance to biotic and abiotic stresses and high nutrient use efficiency. This species presents a challenge to geneticists and breeders due to its large genome containing a high proportion of repetitive sequences, self incompatibility, severe inbreeding depression and tissue culture recalcitrance. The genomic resources currently available for rye are underdeveloped in comparison with other crops of similar economic importance. The aim of this study was to create a highly saturated, multilocus linkage map of rye via consensus mapping, based on Diversity Arrays Technology (DArT markers. METHODOLOGY/PRINCIPAL FINDINGS: Recombinant inbred lines (RILs from 5 populations (564 in total were genotyped using DArT markers and subjected to linkage analysis using Join Map 4.0 and Multipoint Consensus 2.2 software. A consensus map was constructed using a total of 9703 segregating markers. The average chromosome map length ranged from 199.9 cM (2R to 251.4 cM (4R and the average map density was 1.1 cM. The integrated map comprised 4048 loci with the number of markers per chromosome ranging from 454 for 7R to 805 for 4R. In comparison with previously published studies on rye, this represents an eight-fold increase in the number of loci placed on a consensus map and a more than two-fold increase in the number of genetically mapped DArT markers. CONCLUSIONS/SIGNIFICANCE: Through the careful choice of marker type, mapping populations and the use of software packages implementing powerful algorithms for map order optimization, we produced a valuable resource for rye and triticale genomics and breeding, which provides an excellent starting point for more in-depth studies on rye genome organization.

  6. Using SNA to map participation and non-participation in vulnerable populations

    DEFF Research Database (Denmark)

    Hindhede, Anette Lykke

    The pursuit of equality in health is an overriding goal and principle in Danish health policy. Inequality in health prevails especially among population groups with low education and income levels. Many municipalities have therefore been focusing on deprived areas attempting to fight inequality...... in health. This has led to the implementation of various health promoting activities within these areas. Community health promotion requires the participation of local leadership and social networks to facilitate the transmission and uptake of interventions for the overall population to achieve social...... themselves. Thus, understanding the impact of social networks on health requires not only understanding how networks function, but also how they are formed, which raises the issue of role potentially played by selection and homophily (McPherson et al. 2006). Drawing on data from an explorative empirical...

  7. Identifying human disease genes through cross-species gene mapping of evolutionary conserved processes.

    Directory of Open Access Journals (Sweden)

    Martin Poot

    2011-05-01

    Full Text Available Understanding complex networks that modulate development in humans is hampered by genetic and phenotypic heterogeneity within and between populations. Here we present a method that exploits natural variation in highly diverse mouse genetic reference panels in which genetic and environmental factors can be tightly controlled. The aim of our study is to test a cross-species genetic mapping strategy, which compares data of gene mapping in human patients with functional data obtained by QTL mapping in recombinant inbred mouse strains in order to prioritize human disease candidate genes.We exploit evolutionary conservation of developmental phenotypes to discover gene variants that influence brain development in humans. We studied corpus callosum volume in a recombinant inbred mouse panel (C57BL/6J×DBA/2J, BXD strains using high-field strength MRI technology. We aligned mouse mapping results for this neuro-anatomical phenotype with genetic data from patients with abnormal corpus callosum (ACC development.From the 61 syndromes which involve an ACC, 51 human candidate genes have been identified. Through interval mapping, we identified a single significant QTL on mouse chromosome 7 for corpus callosum volume with a QTL peak located between 25.5 and 26.7 Mb. Comparing the genes in this mouse QTL region with those associated with human syndromes (involving ACC and those covered by copy number variations (CNV yielded a single overlap, namely HNRPU in humans and Hnrpul1 in mice. Further analysis of corpus callosum volume in BXD strains revealed that the corpus callosum was significantly larger in BXD mice with a B genotype at the Hnrpul1 locus than in BXD mice with a D genotype at Hnrpul1 (F = 22.48, p<9.87*10(-5.This approach that exploits highly diverse mouse strains provides an efficient and effective translational bridge to study the etiology of human developmental disorders, such as autism and schizophrenia.

  8. Genome-Wide Linkage Mapping of QTL for Adult-Plant Resistance to Stripe Rust in a Chinese Wheat Population Linmai 2 × Zhong 892.

    Directory of Open Access Journals (Sweden)

    Jindong Liu

    Full Text Available Stripe rust is one of the most devastating diseases of wheat (Triticum aestivum worldwide. Adult-plant resistance (APR is an efficient approach to provide long-term protection of wheat from the disease. The Chinese winter wheat cultivar Zhong 892 has a moderate level of APR to stripe rust in the field. To determine the inheritance of the APR resistance in this cultivar, 273 F6 recombinant inbred lines (RILs were developed from a cross between Linmai 2 and Zhong 892. The RILs were evaluated for maximum disease severity (MDS in two sites during the 2011-2012, 2012-2013 and 2013-2014 cropping seasons, providing data for five environments. Illumina 90k SNP (single nucleotide polymorphism chips were used to genotype the RILs and their parents. Composite interval mapping (CIM detected eight QTL, namely QYr.caas-2AL, QYr.caas-2BL.3, QYr.caas-3AS, QYr.caas-3BS, QYr.caas-5DL, QYr.caas-6AL, QYr.caas-7AL and QYr.caas-7DS.1, respectively. All except QYr.caas-2BL.3 resistance alleles were contributed by Zhong 892. QYr.caas-3AS and QYr.caas-3BS conferred stable resistance to stripe rust in all environments, explaining 6.2-17.4% and 5.0-11.5% of the phenotypic variances, respectively. The genome scan of SNP sequences tightly linked to QTL for APR against annotated proteins in wheat and related cereals genomes identified two candidate genes (autophagy-related gene and disease resistance gene RGA1, significantly associated with stripe rust resistance. These QTL and their closely linked SNP markers, in combination with kompetitive allele specific PCR (KASP technology, are potentially useful for improving stripe rust resistances in wheat breeding.

  9. Navigating knowledge to action: a conceptual map for facilitating translation of population health risk planning tools into practice.

    Science.gov (United States)

    Peirson, Leslea; Rosella, Laura

    2015-01-01

    A population health risk tool was created that estimates future diabetes risk and provides outputs that can inform practical and meaningful diabetes prevention strategies and support local decision making and planning. A project was designed to inform and understand knowledge translation and application of this novel tool in multiple health-related settings. Lacking published studies in this area, the authors conceived a conceptual map to guide the project that integrates and adapts elements from several planned action theories. This paper describes the rationale and basis for constructing the Population Health Planning Knowledge-to-Action Model and elaborates on the 2 connected structures of the framework: the Tool Creation Path and the Action Cycle. Although created for an express purpose, this model has the potential to inform application of other tools. This work demonstrates how a research team can adapt and integrate existing frameworks to better align with novel real-world knowledge translation issues. Furthermore, the integration of a population risk tool to support health decision making highlights the interaction between continuing education and knowledge translation. © 2015 The Alliance for Continuing Education in the Health Professions, the Society for Academic Continuing Medical Education, and the Council on Continuing Medical Education, Association for Hospital Medical Education.

  10. Prenatal effects of ancestral irradiation in inbred mice

    International Nuclear Information System (INIS)

    Sprackling, L.E.S.

    1975-01-01

    Mice from 13 inbred strains (S, Z, E, Bab, BaB, BrR, C, K, N, Q, G, CFW, CF1) received continuous cobalt 60 irradiation at low dose rates for varying numbers of consecutive generations. Some Bab and BaB mice had received continuous irradiation for from 24 to 31 generations and the other mice had up to six generations of continuous irradiation in their ancestry. At weaning, the mice were removed from the irradiation room and were mated within strains either to sibs or nonsibs. Ancestral and direct irradiation doses were calculated. The ancestral dose was the effective accumulated dose to the progeny of the mated mice. The direct dose was the amount of irradiation received by any mated female from her conception to her weaning. Each irradiated or control female was scored as fertile or sterile and in utero litter counts were made in pregnant females that were dissected past the tenth day of pregnancy; the sum of moles, dead embryos, and live embryos was the total in utero litter size. A ratio of the living embryos to the total number of embryos in utero was determined for each litter. An increase in ancestral or direct irradiation dose significantly decreased fertility in 11 of the 13 strains. The fertility curves for the pooled data were sigmoid in the area of the doses below those that caused complete sterility. Among the controls, there were significant strain differences in total litter size and in the ratio. Strain X--Y plots, with ancestral or direct doses plotted against total litter size or ratio, revealed the tendency for litter size to decrease as dose increased. The only trend shown for ratio was for the litters with ratios of 0.50 or less to appear more frequently among the irradiated mice. The few corpora lutea counts revealed nothing of significance. Generally, there was a definite trend toward fewer mice alive in utero among the irradiated mice

  11. Variation in Taxonomic Composition of the Fecal Microbiota in an Inbred Mouse Strain across Individuals and Time.

    Science.gov (United States)

    Hoy, Yana Emmy; Bik, Elisabeth M; Lawley, Trevor D; Holmes, Susan P; Monack, Denise M; Theriot, Julie A; Relman, David A

    2015-01-01

    Genetics, diet, and other environmental exposures are thought to be major factors in the development and composition of the intestinal microbiota of animals. However, the relative contributions of these factors in adult animals, as well as variation with time in a variety of important settings, are still not fully understood. We studied a population of inbred, female mice fed the same diet and housed under the same conditions. We collected fecal samples from 46 individual mice over two weeks, sampling four of these mice for periods as long as 236 days for a total of 190 samples, and determined the phylogenetic composition of their microbial communities after analyzing 1,849,990 high-quality pyrosequencing reads of the 16S rRNA gene V3 region. Even under these controlled conditions, we found significant inter-individual variation in community composition, as well as variation within an individual over time, including increases in alpha diversity during the first 2 months of co-habitation. Some variation was explained by mouse membership in different cage and vendor shipment groups. The differences among individual mice from the same shipment group and cage were still significant. Overall, we found that 23% of the variation in intestinal microbiota composition was explained by changes within the fecal microbiota of a mouse over time, 12% was explained by persistent differences among individual mice, 14% by cage, and 18% by shipment group. Our findings suggest that the microbiota of controlled populations of inbred laboratory animals may not be as uniform as previously thought, that animal rearing and handling may account for some variation, and that as yet unidentified factors may explain additional components of variation in the composition of the microbiota within populations and individuals over time. These findings have implications for the design and interpretation of experiments involving laboratory animals.

  12. Functional mapping imprinted quantitative trait loci underlying developmental characteristics

    Directory of Open Access Journals (Sweden)

    Li Gengxin

    2008-03-01

    Full Text Available Abstract Background Genomic imprinting, a phenomenon referring to nonequivalent expression of alleles depending on their parental origins, has been widely observed in nature. It has been shown recently that the epigenetic modification of an imprinted gene can be detected through a genetic mapping approach. Such an approach is developed based on traditional quantitative trait loci (QTL mapping focusing on single trait analysis. Recent studies have shown that most imprinted genes in mammals play an important role in controlling embryonic growth and post-natal development. For a developmental character such as growth, current approach is less efficient in dissecting the dynamic genetic effect of imprinted genes during individual ontology. Results Functional mapping has been emerging as a powerful framework for mapping quantitative trait loci underlying complex traits showing developmental characteristics. To understand the genetic architecture of dynamic imprinted traits, we propose a mapping strategy by integrating the functional mapping approach with genomic imprinting. We demonstrate the approach through mapping imprinted QTL controlling growth trajectories in an inbred F2 population. The statistical behavior of the approach is shown through simulation studies, in which the parameters can be estimated with reasonable precision under different simulation scenarios. The utility of the approach is illustrated through real data analysis in an F2 family derived from LG/J and SM/J mouse stains. Three maternally imprinted QTLs are identified as regulating the growth trajectory of mouse body weight. Conclusion The functional iQTL mapping approach developed here provides a quantitative and testable framework for assessing the interplay between imprinted genes and a developmental process, and will have important implications for elucidating the genetic architecture of imprinted traits.

  13. Hierarchical Structure of the Eysenck Personality Inventory in a Large Population Sample: Goldberg's Trait-Tier Mapping Procedure.

    Science.gov (United States)

    Chapman, Benjamin P; Weiss, Alexander; Barrett, Paul; Duberstein, Paul

    2013-03-01

    The structure of the Eysenck Personality Inventory (EPI) is poorly understood, and applications have mostly been confined to the broad Neuroticism, Extraversion, and Lie scales. Using a hierarchical factoring procedure, we mapped the sequential differentiation of EPI scales from broad, molar factors to more specific, molecular factors, in a UK population sample of over 6500 persons. Replicable facets at the lowest tier of Neuroticism included emotional fragility, mood lability, nervous tension, and rumination. The lowest order set of replicable Extraversion facets consisted of social dynamism, sociotropy, decisiveness, jocularity, social information seeking, and impulsivity. The Lie scale consisted of an interpersonal virtue and a behavioral diligence facet. Users of the EPI may be well served in some circumstances by considering its broad Neuroticism, Extraversion, and Lie scales as multifactorial, a feature that was explicitly incorporated into subsequent Eysenck inventories and is consistent with other hierarchical trait structures.

  14. Association mapping in sunflower for sclerotinia head rot resistance

    Directory of Open Access Journals (Sweden)

    Fusari Corina M

    2012-06-01

    Full Text Available Abstract Background Sclerotinia Head Rot (SHR is one of the most damaging diseases of sunflower in Europe, Argentina, and USA, causing average yield reductions of 10 to 20 %, but leading to total production loss under favorable environmental conditions for the pathogen. Association Mapping (AM is a promising choice for Quantitative Trait Locus (QTL mapping, as it detects relationships between phenotypic variation and gene polymorphisms in existing germplasm without development of mapping populations. This article reports the identification of QTL for resistance to SHR based on candidate gene AM. Results A collection of 94 sunflower inbred lines were tested for SHR under field conditions using assisted inoculation with the fungal pathogen Sclerotinia sclerotiorum. Given that no biological mechanisms or biochemical pathways have been clearly identified for SHR, 43 candidate genes were selected based on previous transcript profiling studies in sunflower and Brassica napus infected with S. sclerotiorum. Associations among SHR incidence and haplotype polymorphisms in 16 candidate genes were tested using Mixed Linear Models (MLM that account for population structure and kinship relationships. This approach allowed detection of a significant association between the candidate gene HaRIC_B and SHR incidence (P  Conclusions These results suggest that AM will be useful in dissecting other complex traits in sunflower, thus providing a valuable tool to assist in crop breeding.

  15. Guide for developing an information technology investment road map for population health management.

    Science.gov (United States)

    Hunt, Jacquelyn S; Gibson, Richard F; Whittington, John; Powell, Kitty; Wozney, Brad; Knudson, Susan

    2015-06-01

    Many health systems recovering from a massive investment in electronic health records are now faced with the prospect of maturing into accountable care organizations. This maturation includes the need to cooperate with new partners, involve substantially new data sources, require investment in additional information technology (IT) solutions, and become proficient in managing care from a new perspective. Adding to the confusion, there are hundreds of population health management (PHM) vendors with overlapping product functions. This article proposes an organized approach to investing in PHM IT. The steps include assessing the organization's business and clinical goals, establishing governance, agreeing on business requirements, evaluating the ability of current IT systems to meet those requirements, setting time lines and budgets, rationalizing current and future needs and capabilities, and installing the new systems in the context of a continuously learning organization. This article will help organizations chart their position on the population health readiness spectrum and enhance their chances for a successful transition from volume-based to value-based care.

  16. Linkage mapping of Barley yellow dwarf virus resistance in connected populations of maize.

    Science.gov (United States)

    Horn, Frederike; Habekuss, Antje; Stich, Benjamin

    2015-02-03

    With increasing winter temperatures, Barley yellow dwarf virus (BYDV) is expected to become an increasing problem in maize cultivation in Germany. Earlier studies revealed that BYDV has a negative impact on maize performance. Molecular markers would accelerate the development of BYDV resistant maize. Therefore, the objectives of this study were (i) the identification of quantitative trait loci (QTL) for BYDV resistance in five connected segregating maize populations in a field experiment and (ii) their comparison with the QTL detected under greenhouse conditions. In linkage analyses of the traits virus extinction, infection rate, and the symptom red edges, a highly associated major QTL was identified on chromosome 10. This QTL explained 45% of the phenotypic variance for the traits virus extinction and infection rate and 30% for the symptom red edges. We could show that BYDV resistance traits are oligogenically inherited. The QTL on chromosome 10 could be observed in the connected linkage analyses and in the single population analyses. Furthermore, this QTL could also be confirmed in the greenhouse experiment. Our results let suggest that this QTL is involved in multiple virus resistance and the markers are promising for marker assisted selection.

  17. Association mapping of quantitative disease resistance in a natural population of loblolly pine (Pinus taeda L.).

    Science.gov (United States)

    Quesada, Tania; Gopal, Vikneswaran; Cumbie, W Patrick; Eckert, Andrew J; Wegrzyn, Jill L; Neale, David B; Goldfarb, Barry; Huber, Dudley A; Casella, George; Davis, John M

    2010-10-01

    Genetic resistance to disease incited by necrotrophic pathogens is not well understood in plants. Whereas resistance is often quantitative, there is limited information on the genes that underpin quantitative variation in disease resistance. We used a population genomic approach to identify genes in loblolly pine (Pinus taeda) that are associated with resistance to pitch canker, a disease incited by the necrotrophic pathogen Fusarium circinatum. A set of 498 largely unrelated, clonally propagated genotypes were inoculated with F. circinatum microconidia and lesion length, a measure of disease resistance, data were collected 4, 8, and 12 weeks after inoculation. Best linear unbiased prediction was used to adjust for imbalance in number of observations and to identify highly susceptible and highly resistant genotypes ("tails"). The tails were reinoculated to validate the results of the full population screen. Significant associations were detected in 10 single nucleotide polymorphisms (SNPs) (out of 3938 tested). As hypothesized for genes involved in quantitative resistance, the 10 SNPs had small effects and proposed roles in basal resistance, direct defense, and signal transduction. We also discovered associated genes with unknown function, which would have remained undetected in a candidate gene approach constrained by annotation for disease resistance or stress response.

  18. Mapping the exposure of the Brazilian population to natural background radiation - cosmic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Rochedo, Elaine R.R., E-mail: elaine@ird.gov.br [Instituto de Radioprotecao e Dosimetria (lRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Salles, Krause C.S.; Prado, Nadya M.C., E-mail: krausesalles@yahoo.com.br, E-mail: nadya@ime.ib.br [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    The main objective of this work is to statically and graphically describe the exposure of the Brazilian population to natural background radiation. in this stage, doses due to cosmic rays is being assessed based on sea level dose rates, corrected by latitude and altitude, according to the model recommended by UNSCEAR. In this work, the doses were estimated for ali Brazilian municipalities with more than 100.000 inhabitants. The 253 municipalities selected for this study include about 52% of the Brazilian population. Average dose rate was estimated to be about 50 n Sv/h with a variation coefficient of 31%. The estimated doses have shown a strong influence of altitude on dose rates, with a correlation coefficient of 0,998 for ao exponential fit. This result confirms previous studies that show a large effect of the altitude 00 exposure from cosmic radiation. Considering the same occupation and shielding conditions used by UNSCEAR as global averages, average annual dose was estimated to be 0,37 (0,24 - 0,76) mSv/y, very close to UNSCEAR worldwide average of 0,38 (0,3 - 1,0) mSv/y. (author)

  19. Mapping the exposure of the Brazilian population to natural background radiation - cosmic radiation

    International Nuclear Information System (INIS)

    Rochedo, Elaine R.R.; Salles, Krause C.S.; Prado, Nadya M.C.

    2013-01-01

    The main objective of this work is to statically and graphically describe the exposure of the Brazilian population to natural background radiation. in this stage, doses due to cosmic rays is being assessed based on sea level dose rates, corrected by latitude and altitude, according to the model recommended by UNSCEAR. In this work, the doses were estimated for ali Brazilian municipalities with more than 100.000 inhabitants. The 253 municipalities selected for this study include about 52% of the Brazilian population. Average dose rate was estimated to be about 50 n Sv/h with a variation coefficient of 31%. The estimated doses have shown a strong influence of altitude on dose rates, with a correlation coefficient of 0,998 for ao exponential fit. This result confirms previous studies that show a large effect of the altitude 00 exposure from cosmic radiation. Considering the same occupation and shielding conditions used by UNSCEAR as global averages, average annual dose was estimated to be 0,37 (0,24 - 0,76) mSv/y, very close to UNSCEAR worldwide average of 0,38 (0,3 - 1,0) mSv/y. (author)

  20. Sub-national mapping of population pyramids and dependency ratios in Africa and Asia

    Science.gov (United States)

    Pezzulo, Carla; Hornby, Graeme M.; Sorichetta, Alessandro; Gaughan, Andrea E.; Linard, Catherine; Bird, Tomas J.; Kerr, David; Lloyd, Christopher T.; Tatem, Andrew J.

    2017-07-01

    The age group composition of populations varies substantially across continents and within countries, and is linked to levels of development, health status and poverty. The subnational variability in the shape of the population pyramid as well as the respective dependency ratio are reflective of the different levels of development of a country and are drivers for a country's economic prospects and health burdens. Whether measured as the ratio between those of working age and those young and old who are dependent upon them, or through separate young and old-age metrics, dependency ratios are often highly heterogeneous between and within countries. Assessments of subnational dependency ratio and age structure patterns have been undertaken for specific countries and across high income regions, but to a lesser extent across the low income regions. In the framework of the WorldPop Project, through the assembly of over 100 million records across 6,389 subnational administrative units, subnational dependency ratio and high resolution gridded age/sex group datasets were produced for 87 countries in Africa and Asia.

  1. Using SNA to map participation and non-participation in vulnerable populations

    DEFF Research Database (Denmark)

    Hindhede, Anette Lykke

    change. This approach is based on an understanding of local residential areas as homogeneous (Barnes 1954). There is, however, a lack of knowledge of whether this seems to be the case and on the actual coverage of these health promotion initiatives. Non-participants appear to have greater clinical need...... in health. This has led to the implementation of various health promoting activities within these areas. Community health promotion requires the participation of local leadership and social networks to facilitate the transmission and uptake of interventions for the overall population to achieve social...... or risk factors suggesting that a differential uptake may lead to sub-optimal health gain and contribute to inequalities via the inverse care law (Dryden et al 2012). One of the most striking features of social networks is homophily; the tendency for people to affiliate and associate with others like...

  2. A map of human genome variation from population-scale sequencing.

    Science.gov (United States)

    Abecasis, Gonçalo R; Altshuler, David; Auton, Adam; Brooks, Lisa D; Durbin, Richard M; Gibbs, Richard A; Hurles, Matt E; McVean, Gil A

    2010-10-28

    The 1000 Genomes Project aims to provide a deep characterization of human genome sequence variation as a foundation for investigating the relationship between genotype and phenotype. Here we present results of the pilot phase of the project, designed to develop and compare different strategies for genome-wide sequencing with high-throughput platforms. We undertook three projects: low-coverage whole-genome sequencing of 179 individuals from four populations; high-coverage sequencing of two mother-father-child trios; and exon-targeted sequencing of 697 individuals from seven populations. We describe the location, allele frequency and local haplotype structure of approximately 15 million single nucleotide polymorphisms, 1 million short insertions and deletions, and 20,000 structural variants, most of which were previously undescribed. We show that, because we have catalogued the vast majority of common variation, over 95% of the currently accessible variants found in any individual are present in this data set. On average, each person is found to carry approximately 250 to 300 loss-of-function variants in annotated genes and 50 to 100 variants previously implicated in inherited disorders. We demonstrate how these results can be used to inform association and functional studies. From the two trios, we directly estimate the rate of de novo germline base substitution mutations to be approximately 10(-8) per base pair per generation. We explore the data with regard to signatures of natural selection, and identify a marked reduction of genetic variation in the neighbourhood of genes, due to selection at linked sites. These methods and public data will support the next phase of human genetic research.

  3. Comparative mapping in watermelon [Citrullus lanatus (Thunb.) Matsum. et Nakai].

    Science.gov (United States)

    Sandlin, Katherine; Prothro, Jason; Heesacker, Adam; Khalilian, Nelly; Okashah, Rebecca; Xiang, Wenwen; Bachlava, Eleni; Caldwell, David G; Taylor, Chris A; Seymour, Danelle K; White, Victoria; Chan, Eva; Tolla, Greg; White, Cathy; Safran, Dolores; Graham, Elaine; Knapp, Steven; McGregor, Cecilia

    2012-12-01

    The first single-nucleotide polymorphism (SNP) maps for watermelon [Citrullus lanatus (Thunb.) Matsum. et Nakai] were constructed and compared. Three populations were developed from crosses between two elite cultivars, Klondike Black Seeded × New Hampshire Midget (KBS × NHM), an elite cultivar and wild egusi accession, Strain II × PI 560023 (SII × Egusi) and an elite cultivar and a wild citron accession, ZWRM50 × PI 244019 (ZWRM × Citroides). The SII × Egusi and ZWRM × Citroides F(2) populations consisted of 187 and 182 individuals respectively while the KBS × NHM recombinant inbred line (RIL) population consisted of 164 lines. The length of the genetic maps were 1,438, 1,514 and 1,144 cM with average marker distances of 3.8, 4.2, and 3.4 cM for the KBS × NHM, SII × Egusi and ZWRM × Citroides populations, respectively. Shared markers were used to align the three maps so that the linkage groups (LGs) represented the 11 chromosomes of the species. Marker segregation distortion were observed in all three populations, but was highest (12.7 %) in the ZWRM × Citroides population, where Citroides alleles were favored. The three maps were used to construct a consensus map containing 378 SNP markers with an average distance of 5.1 cM between markers. Phenotypic data was collected for fruit weight (FWT), fruit length (FL), fruit width (FWD), fruit shape index (FSI), rind thickness (RTH) and Brix (BRX) and analyzed for quantitative trait loci (QTL) associated with these traits. A total of 40 QTL were identified in the three populations, including major QTL for fruit size and shape that were stable across genetic backgrounds and environments. The present study reports the first SNP maps for Citrullus and the first map constructed using two elite parents. We also report the first stable QTL associated with fruit size and shape in Citrullus lanatus. These maps, QTL and SNPs should be useful for the watermelon community and represent a significant step towards the

  4. Inbred Strain Variant Database (ISVdb: A Repository for Probabilistically Informed Sequence Differences Among the Collaborative Cross Strains and Their Founders

    Directory of Open Access Journals (Sweden)

    Daniel Oreper

    2017-06-01

    Full Text Available The Collaborative Cross (CC is a panel of recently established multiparental recombinant inbred mouse strains. For the CC, as for any multiparental population (MPP, effective experimental design and analysis benefit from detailed knowledge of the genetic differences between strains. Such differences can be directly determined by sequencing, but until now whole-genome sequencing was not publicly available for individual CC strains. An alternative and complementary approach is to infer genetic differences by combining two pieces of information: probabilistic estimates of the CC haplotype mosaic from a custom genotyping array, and probabilistic variant calls from sequencing of the CC founders. The computation for this inference, especially when performed genome-wide, can be intricate and time-consuming, requiring the researcher to generate nontrivial and potentially error-prone scripts. To provide standardized, easy-to-access CC sequence information, we have developed the Inbred Strain Variant Database (ISVdb. The ISVdb provides, for all the exonic variants from the Sanger Institute mouse sequencing dataset, direct sequence information for CC founders and, critically, the imputed sequence information for CC strains. Notably, the ISVdb also: (1 provides predicted variant consequence metadata; (2 allows rapid simulation of F1 populations; and (3 preserves imputation uncertainty, which will allow imputed data to be refined in the future as additional sequencing and genotyping data are collected. The ISVdb information is housed in an SQL database and is easily accessible through a custom online interface (http://isvdb.unc.edu, reducing the analytic burden on any researcher using the CC.

  5. Mapping Application for Penguin Populations and Projected Dynamics (MAPPPD): Data and Tools for Dynamic Management and Decision Support

    Science.gov (United States)

    Humphries, G. R. W.; Naveen, R.; Schwaller, M.; Che-Castaldo, C.; McDowall, P.; Schrimpf, M.; Schrimpf, Michael; Lynch, H. J.

    2017-01-01

    The Mapping Application for Penguin Populations and Projected Dynamics (MAPPPD) is a web-based, open access, decision-support tool designed to assist scientists, non-governmental organizations and policy-makers working to meet the management objectives as set forth by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) and other components of the Antarctic Treaty System (ATS) (that is, Consultative Meetings and the ATS Committee on Environmental Protection). MAPPPD was designed specifically to complement existing efforts such as the CCAMLR Ecosystem Monitoring Program (CEMP) and the ATS site guidelines for visitors. The database underlying MAPPPD includes all publicly available (published and unpublished) count data on emperor, gentoo, Adelie) and chinstrap penguins in Antarctica. Penguin population models are used to assimilate available data into estimates of abundance for each site and year.Results are easily aggregated across multiple sites to obtain abundance estimates over any user-defined area of interest. A front end web interface located at www.penguinmap.com provides free and ready access to the most recent count and modelled data, and can act as a facilitator for data transfer between scientists and Antarctic stakeholders to help inform management decisions for the continent.

  6. Population resizing on fitness improvement genetic algorithm to optimize promotion visit route based on android and google maps API

    Science.gov (United States)

    Listyorini, Tri; Muzid, Syafiul

    2017-06-01

    The promotion team of Muria Kudus University (UMK) has done annual promotion visit to several senior high schools in Indonesia. The visits were done to numbers of schools in Kudus, Jepara, Demak, Rembang and Purwodadi. To simplify the visit, each visit round is limited to 15 (fifteen) schools. However, the team frequently faces some obstacles during the visit, particularly in determining the route that they should take toward the targeted school. It is due to the long distance or the difficult route to reach the targeted school that leads to elongated travel duration and inefficient fuel cost. To solve these problems, the development of a certain application using heuristic genetic algorithm method based on the dynamic of population size or Population Resizing on Fitness lmprovement Genetic Algorithm (PRoFIGA), was done. This android-based application was developed to make the visit easier and to determine a shorter route for the team, hence, the visiting period will be effective and efficient. The result of this research was an android-based application to determine the shortest route by combining heuristic method and Google Maps Application Programming lnterface (API) that display the route options for the team.

  7. Yield-related salinity tolerance traits identified in a nested association mapping (NAM) population of wild barley

    KAUST Repository

    Saade, Stephanie

    2016-09-02

    Producing sufficient food for nine billion people by 2050 will be constrained by soil salinity, especially in irrigated systems. To improve crop yield, greater understanding of the genetic control of traits contributing to salinity tolerance in the field is needed. Here, we exploit natural variation in exotic germplasm by taking a genome-wide association approach to a new nested association mapping population of barley called HEB-25. The large population (1,336 genotypes) allowed cross-validation of loci, which, along with two years of phenotypic data collected from plants irrigated with fresh and saline water, improved statistical power. We dissect the genetic architecture of flowering time under high salinity and we present genes putatively affecting this trait and salinity tolerance. In addition, we identify a locus on chromosome 2H where, under saline conditions, lines homozygous for the wild allele yielded 30% more than did lines homozygous for the Barke allele. Introgressing this wild allele into elite cultivars could markedly improve yield under saline conditions. © 2016 The Author(s).

  8. QTL analysis of novel genomic regions associated with yield and yield related traits in new plant type based recombinant inbred lines of rice (Oryza sativa L.).

    Science.gov (United States)

    Marathi, Balram; Guleria, Smriti; Mohapatra, Trilochan; Parsad, Rajender; Mariappan, Nagarajan; Kurungara, Vinod Kunnummal; Atwal, Salwandir Singh; Prabhu, Kumble Vinod; Singh, Nagendra Kumar; Singh, Ashok Kumar

    2012-08-09

    Rice is staple food for more than half of the world's population including two billion Asians, who obtain 60-70% of their energy intake from rice and its derivatives. To meet the growing demand from human population, rice varieties with higher yield potential and greater yield stability need to be developed. The favourable alleles for yield and yield contributing traits are distributed among two subspecies i.e., indica and japonica of cultivated rice (Oryza sativa L.). Identification of novel favourable alleles in indica/japonica will pave way to marker-assisted mobilization of these alleles in to a genetic background to break genetic barriers to yield. A new plant type (NPT) based mapping population of 310 recombinant inbred lines (RILs) was used to map novel genomic regions and QTL hotspots influencing yield and eleven yield component traits. We identified major quantitative trait loci (QTLs) for days to 50% flowering (R2 = 25%, LOD = 14.3), panicles per plant (R2 = 19%, LOD = 9.74), flag leaf length (R2 = 22%, LOD = 3.05), flag leaf width (R2 = 53%, LOD = 46.5), spikelets per panicle (R2 = 16%, LOD = 13.8), filled grains per panicle (R2 = 22%, LOD = 15.3), percent spikelet sterility (R2 = 18%, LOD = 14.24), thousand grain weight (R2 = 25%, LOD = 12.9) and spikelet setting density (R2 = 23%, LOD = 15) expressing over two or more locations by using composite interval mapping. The phenotypic variation (R2) ranged from 8 to 53% for eleven QTLs expressing across all three locations. 19 novel QTLs were contributed by the NPT parent, Pusa1266. 15 QTL hotpots on eight chromosomes were identified for the correlated traits. Six epistatic QTLs effecting five traits at two locations were identified. A marker interval (RM3276-RM5709) on chromosome 4 harboring major QTLs for four traits was identified. The present study reveals that favourable alleles for yield and yield contributing traits were

  9. A High Resolution Genetic Map Anchoring Scaffolds of the Sequenced Watermelon Genome

    Science.gov (United States)

    Kou, Qinghe; Jiang, Jiao; Guo, Shaogui; Zhang, Haiying; Hou, Wenju; Zou, Xiaohua; Sun, Honghe; Gong, Guoyi; Levi, Amnon; Xu, Yong

    2012-01-01

    As part of our ongoing efforts to sequence and map the watermelon (Citrullus spp.) genome, we have constructed a high density genetic linkage map. The map positioned 234 watermelon genome sequence scaffolds (an average size of 1.41 Mb) that cover about 330 Mb and account for 93.5% of the 353 Mb of the assembled genomic sequences of the elite Chinese watermelon line 97103 (Citrullus lanatus var. lanatus). The genetic map was constructed using an F8 population of 103 recombinant inbred lines (RILs). The RILs are derived from a cross between the line 97103 and the United States Plant Introduction (PI) 296341-FR (C. lanatus var. citroides) that contains resistance to fusarium wilt (races 0, 1, and 2). The genetic map consists of eleven linkage groups that include 698 simple sequence repeat (SSR), 219 insertion-deletion (InDel) and 36 structure variation (SV) markers and spans ∼800 cM with a mean marker interval of 0.8 cM. Using fluorescent in situ hybridization (FISH) with 11 BACs that produced chromosome-specifc signals, we have depicted watermelon chromosomes that correspond to the eleven linkage groups constructed in this study. The high resolution genetic map developed here should be a useful platform for the assembly of the watermelon genome, for the development of sequence-based markers used in breeding programs, and for the identification of genes associated with important agricultural traits. PMID:22247776

  10. Construction of a dense genetic linkage map and mapping quantitative trait loci for economic traits of a doubled haploid population of Pyropia haitanensis (Bangiales, Rhodophyta).

    Science.gov (United States)

    Xu, Yan; Huang, Long; Ji, Dehua; Chen, Changsheng; Zheng, Hongkun; Xie, Chaotian

    2015-09-21

    Pyropia haitanensis is one of the most economically important mariculture crops in China. A high-density genetic map has not been published yet and quantitative trait locus (QTL) mapping has not been undertaken for P. haitanensis because of a lack of sufficient molecular markers. Specific length amplified fragment sequencing (SLAF-seq) was developed recently for large-scale, high resolution de novo marker discovery and genotyping. In this study, SLAF-seq was used to obtain mass length polymorphic markers to construct a high-density genetic map for P. haitanensis. In total, 120.33 Gb of data containing 75.21 M pair-end reads was obtained after sequencing. The average coverage for each SLAF marker was 75.50-fold in the male parent, 74.02-fold in the female parent, and 6.14-fold average in each double haploid individual. In total, 188,982 SLAFs were detected, of which 6731 were length polymorphic SLAFs that could be used to construct a genetic map. The final map included 4550 length polymorphic markers that were combined into 740 bins on five linkage groups, with a length of 874.33 cM and an average distance of 1.18 cM between adjacent bins. This map was used for QTL mapping to identify chromosomal regions associated with six economically important traits: frond length, width, thickness, fresh weight, growth rates of frond length and growth rates of fresh weight. Fifteen QTLs were identified for these traits. The value of phenotypic variance explained by an individual QTL ranged from 9.59 to 16.61 %, and the confidence interval of each QTL ranged from 0.97 cM to 16.51 cM. The first high-density genetic linkage map for P. haitanensis was constructed, and fifteen QTLs associated with six economically important traits were identified. The results of this study not only provide a platform for gene and QTL fine mapping, map-based gene isolation, and molecular breeding for P. haitanensis, but will also serve as a reference for positioning sequence scaffolds on a physical

  11. Association mapping of insecticide resistance in wild Anopheles gambiae populations: major variants identified in a low-linkage disequilbrium genome.

    Directory of Open Access Journals (Sweden)

    David Weetman

    2010-10-01

    Full Text Available Association studies are a promising way to uncover the genetic basis of complex traits in wild populations. Data on population stratification, linkage disequilibrium and distribution of variant effect-sizes for different trait-types are required to predict study success but are lacking for most taxa. We quantified and investigated the impacts of these key variables in a large-scale association study of a strongly selected trait of medical importance: pyrethroid resistance in the African malaria vector Anopheles gambiae.We genotyped ≈1500 resistance-phenotyped wild mosquitoes from Ghana and Cameroon using a 1536-SNP array enriched for candidate insecticide resistance gene SNPs. Three factors greatly impacted study power. (1 Population stratification, which was attributable to co-occurrence of molecular forms (M and S, and cryptic within-form stratification necessitating both a partitioned analysis and genomic control. (2 All SNPs of substantial effect (odds ratio, OR>2 were rare (minor allele frequency, MAF<0.05. (3 Linkage disequilibrium (LD was very low throughout most of the genome. Nevertheless, locally high LD, consistent with a recent selective sweep, and uniformly high ORs in each subsample facilitated significant direct and indirect detection of the known insecticide target site mutation kdr L1014F (OR≈6; P<10(-6, but with resistance level modified by local haplotypic background.Primarily as a result of very low LD in wild A. Gambiae, LD-based association mapping is challenging, but is feasible at least for major effect variants, especially where LD is enhanced by selective sweeps. Such variants will be of greatest importance for predictive diagnostic screening.

  12. GIS Database and Google Map of the Population at Risk of Cholangiocarcinoma in Mueang Yang District, Nakhon Ratchasima Province of Thailand.

    Science.gov (United States)

    Kaewpitoon, Soraya J; Rujirakul, Ratana; Joosiri, Apinya; Jantakate, Sirinun; Sangkudloa, Amnat; Kaewthani, Sarochinee; Chimplee, Kanokporn; Khemplila, Kritsakorn; Kaewpitoon, Natthawut

    2016-01-01

    Cholangiocarcinoma (CCA) is a serious problem in Thailand, particularly in the northeastern and northern regions. Database of population at risk are need required for monitoring, surveillance, home health care, and home visit. Therefore, this study aimed to develop a geographic information system (GIS) database and Google map of the population at risk of CCA in Mueang Yang district, Nakhon Ratchasima province, northeastern Thailand during June to October 2015. Populations at risk were screened using the Korat CCA verbal screening test (KCVST). Software included Microsoft Excel, ArcGIS, and Google Maps. The secondary data included the point of villages, sub-district boundaries, district boundaries, point of hospital in Mueang Yang district, used for created the spatial databese. The populations at risk for CCA and opisthorchiasis were used to create an arttribute database. Data were tranfered to WGS84 UTM ZONE 48. After the conversion, all of the data were imported into Google Earth using online web pages www.earthpoint.us. Some 222 from a 4,800 population at risk for CCA constituted a high risk group. Geo-visual display available at following www.google.com/maps/d/u/0/ edit?mid=zPxtcHv_iDLo.kvPpxl5mAs90 and hl=th. Geo-visual display 5 layers including: layer 1, village location and number of the population at risk for CCA; layer 2, sub-district health promotion hospital in Mueang Yang district and number of opisthorchiasis; layer 3, sub-district district and the number of population at risk for CCA; layer 4, district hospital and the number of population at risk for CCA and number of opisthorchiasis; and layer 5, district and the number of population at risk for CCA and number of opisthorchiasis. This GIS database and Google map production process is suitable for further monitoring, surveillance, and home health care for CCA sufferers.

  13. Combining abilities of inbred lines for dry matter yield of maize (Zea mays L. Hybrids

    Directory of Open Access Journals (Sweden)

    Sečanski Mile

    2003-01-01

    Full Text Available This study encompass the investigation on combining abilities of six maize inbred lines and their diallel hybrids of F1 generation for dry matter yield of both, the whole plant and the ear. The analysis of combining abilities was performed following Griffing (1956 method 2, model I, without reciprocal crosses, while the analysis the genetic components of variance and the regression analysis were done after the model proposed by Hayman and Jinks (1954 and Mather and Jink (1971. Dominant gene effects in inheritance of dry matter yield of the whole plant and the ear were determined by the analysis of combining abilities. The role of these effects are also observable from the analysis of genetic components of variations and results of the Vr/Wr regression analysis. The inbred line ZPLB 406 was the inbred with the highest GCA effects. .

  14. Advances in sorghum genetic mapping with implications for sorghum improvement

    International Nuclear Information System (INIS)

    Lee, M.

    1998-01-01

    Despite the importance of the sorghum crop, comprehensive genetic characterization has been limited. Therefore, the primary goal of this research program was to develop basic genetic tools to facilitate research in the genetics and breeding of sorghum. The first phase of this project consisted of constructing a genetic map based on restriction fragment length polymorphisms (RFLPs). The ISU sorghum map was created through linkage analysis of 78 F2 plants of an intraspecific cross between inbred CK60 and accession PI229828. Subsequent mapping, efforts in several labs have enriched the sorghum map to the point where it now contains over 1,500 loci defined by RFLPs and many others defined by mutant phenotypes and QTLs. The ISU map consists of 201 loci distributed among 10 linkage groups covering 1299 cM. Comparison of sorghum and maize RFLP maps on the basis of common sets of DNA probes revealed a high degree of conservation as reflected by homology, copy number, and colinearity. Examples of conserved and rearranged locus orders were observed. The same sorghum population was used to map genetic factors (mutants and QTLS) for several traits including vegetative and reproductive morphology, maturity, insect, and disease resistance. Four QTLs for plant height, an important character for sorghum adaptation in temperate latitudes for grain production, were identified in a sample of 152 F2 plants whereas 6 QTLs were detected among their F3 progeny. These observations and assessments of other traits at 4 QTLs common to F2 plants and their F3 progeny indicate some of these regions correspond to loci (dw) previously identified on the basis of alleles with highly qualitative effects. Four of the six sorghum plant height QTLs seem to be orthologous to plant height QTLs in maize. Other possible instances of orthologous QTLs included regions for maturity and tillering. These observations suggest that the conservation of the maize and sorghum genomes encompasses sequence homology

  15. Mapping of a Major QTL for Ceratocystis Wilt Disease in an F1 Population of Theobroma cacao

    Directory of Open Access Journals (Sweden)

    Luciel dos Santos Fernandes

    2018-02-01

    Full Text Available Cacao is an important crop, its beans are key raw materials for the chocolate and cosmetic industries. Ceratocystis wilt of cacao (CWC caused by Ceratocystis cacaofunesta is a lethal disease for the crop. Therefore, the selection of resistant cacao varieties is one of the viable ways to minimize losses in cacao production. In this paper, we described the identification of a major QTL associated with CWC in an F1 mapping population from a cross between a resistant, “TSH 1188,” and a susceptible genotype, “CCN 51.” A set of 266 trees were genotyped using 3,526 single nucleotide polymorphic markers and then multiple QTL mapping analyses were performed. Two QTLs were identified on chromosomes IV and VI. The major QTL was located at 20 cM from the top position of chromosome VI, accounting for more than 60% of the phenotypic variation. The favorable allele T1, with haplotype GTT, came from the “TSH 1188” parent. It was evident that the haplotype combination T1C2 on chromosome VI was the most significant for resistance, since 93% of resistant trees had this haplotype. The major QTL converged to a genomic region of 739.4 kb that harbored nine candidate genes, including two major classes of resistance genes, which would make them the primary candidates involved in the resistance to CWC. The haplotypes detected are now used to improve the efficiency and precision of the selection of resistant trees in cacao breeding.

  16. Inbreeding depression increases susceptibility to bovine tuberculosis in lions: an experimental test using an inbred-outbred contrast through translocation.

    Science.gov (United States)

    Trinkel, Martina; Cooper, Dave; Packer, Craig; Slotow, Rob

    2011-07-01

    Disease can dramatically influence the dynamics of endangered wildlife populations, especially when they are small and isolated, with increased risk of inbreeding. In Hluhluwe-iMfolozi Park (HiP), a small, enclosed reserve in South Africa, a large lion (Panthera leo) population arose from a small founder group in the 1960s and started showing conspicuous signs of inbreeding. To restore the health status of the HiP lion population, outbred lions were translocated into the existing population. In this study, we determined the susceptibility to bovine tuberculosis (bTB), and the prevalence of antibody to feline viruses of native lions, and compared the findings with those from translocated outbred lions and their offspring. Antibodies to feline herpesvirus, feline calicivirus, feline parvovirus, and feline coronavirus were present in the lion population, but there was no significant difference in antibody prevalence between native and translocated lions and their offspring, and these feline viruses did not appear to have an effect on the clinical health of HiP lions. However, feline immunodeficiency virus (FIV), which was previously absent from HiP, appears to have been introduced into the lion population through translocation. Within 7 yr, the prevalence of antibody to FIV increased up to 42%. Bovine tuberculosis posed a major threat to the inbred native lion population, but not to translocated lions and their offspring. More than 30% of the native lion population died from bTB or malnutrition compared with lions and their offspring. We have demonstrated that management of population genetics through supplementation can successfully combat a disease that threatens population persistence. However, great care must be taken not to introduce new diseases into populations through translocation.

  17. Fine-scale mapping of a locus for severe bipolar mood disorder on chromosome 18p11.3 in the Costa Rican population

    Science.gov (United States)

    McInnes, L. Alison; Service, Susan K.; Reus, Victor I.; Barnes, Glenn; Charlat, Olga; Jawahar, Satya; Lewitzky, Steve; Yang, Qing; Duong, Quyen; Spesny, Mitzi; Araya, Carmen; Araya, Xinia; Gallegos, Alvaro; Meza, Luis; Molina, Julio; Ramirez, Rolando; Mendez, Roxana; Silva, Sandra; Fournier, Eduardo; Batki, Steven L.; Mathews, Carol A.; Neylan, Thomas; Glatt, Charles E.; Escamilla, Michael A.; Luo, David; Gajiwala, Paresh; Song, Terry; Crook, Stephen; Nguyen, Jasmine B.; Roche, Erin; Meyer, Joanne M.; Leon, Pedro; Sandkuijl, Lodewijk A.; Freimer, Nelson B.; Chen, Hong

    2001-01-01

    We have searched for genes predisposing to bipolar disorder (BP) by studying individuals with the most extreme form of the affected phenotype, BP-I, ascertained from the genetically isolated population of the Central Valley of Costa Rica (CVCR). The results of a previous linkage analysis on two extended CVCR BP-I pedigrees, CR001 and CR004, and of linkage disequilibrium (LD) analyses of a CVCR population sample of BP-I patients implicated a candidate region on 18p11.3. We further investigated this region by creating a physical map and developing 4 new microsatellite and 26 single-nucleotide polymorphism markers for typing in the pedigree and population samples. We report the results of fine-scale association analyses in the population sample, as well as evaluation of haplotypes in pedigree CR001. Our results suggest a candidate region containing six genes but also highlight the complexities of LD mapping of common disorders. PMID:11572994

  18. Comparative mapping in intraspecific populations uncovers a high degree of macrosynteny between A- and B-genome diploid species of peanut

    Directory of Open Access Journals (Sweden)

    Guo Yufang

    2012-11-01

    Full Text Available Abstract Background Cultivated peanut or groundnut (Arachis hypogaea L. is an important oilseed crop with an allotetraploid genome (AABB, 2n = 4x = 40. Both the low level of genetic variation within the cultivated gene pool and its polyploid nature limit the utilization of molecular markers to explore genome structure and facilitate genetic improvement. Nevertheless, a wealth of genetic diversity exists in diploid Arachis species (2n = 2x = 20, which represent a valuable gene pool for cultivated peanut improvement. Interspecific populations have been used widely for genetic mapping in diploid species of Arachis. However, an intraspecific mapping strategy was essential to detect chromosomal rearrangements among species that could be obscured by mapping in interspecific populations. To develop intraspecific reference linkage maps and gain insights into karyotypic evolution within the genus, we comparatively mapped the A- and B-genome diploid species using intraspecific F2 populations. Exploring genome organization among diploid peanut species by comparative mapping will enhance our understanding of the cultivated tetraploid peanut genome. Moreover, new sources of molecular markers that are highly transferable between species and developed from expressed genes will be required to construct saturated genetic maps for peanut. Results A total of 2,138 EST-SSR (expressed sequence tag-simple sequence repeat markers were developed by mining a tetraploid peanut EST assembly including 101,132 unigenes (37,916 contigs and 63,216 singletons derived from 70,771 long-read (Sanger and 270,957 short-read (454 sequences. A set of 97 SSR markers were also developed by mining 9,517 genomic survey sequences of Arachis. An SSR-based intraspecific linkage map was constructed using an F2 population derived from a cross between K 9484 (PI 298639 and GKBSPSc 30081 (PI 468327 in the B-genome species A. batizocoi. A high degree of macrosynteny was observed

  19. Mapping of quantitative trait loci controlling Orobanche foetida Poir ...

    African Journals Online (AJOL)

    In this study we have identified and map the quantitative trait loci (QTL) controlling resistance to O. foetida in faba bean (Vicia faba) and studied their stability in two different environments. One hundred and forty four Recombinant Inbred Lines (RILs) derived from the cross between a susceptible and a resistant parent were ...

  20. Display of individuality in avoidance behavior and risk assessment of inbred mice

    Directory of Open Access Journals (Sweden)

    Torben eHager

    2014-09-01

    Full Text Available Factors determining individuality are still poorly understood. Rodents are excellent model organisms to study individuality, due to a rich behavioral repertoire and the availability of well-characterized isogenic populations. However, most current behavioral assays for rodents have short test duration in novel test environments and require human interference, which introduce coercion, thereby limiting the assessment of naturally occurring individuality. Thus, we developed an automated behavior system to longitudinally monitor conditioned fear for assessing PTSD-like behavior in individual mice. The system consists of a safe home compartment connected to a risk-prone test compartment (TC. Entry and exploration of the TC is solely based on deliberate choice determined by individual fear responsiveness and fear extinction. In this novel ethological assay, C57BL/6J mice show homogeneous responses after shock exposure (innate fear, but striking variation in long-lasting fear responses based on avoidance and risk assessment (learned fear, including automated stretch-attend posture quantification. TC entry (retention latencies after foot shock differed >24 h and the re-explored TC area differed >50% among inbred mice. Next, we compared two closely related C57BL/6 substrains. Despite substantial individual differences, previously observed higher fear of C57BL/6N versus C57BL/6J mice was reconfirmed, whereas fear extinction was fast and did not differ. The observed variation in fear expression in isogenic mice suggests individual differences in coping style with PTSD-like avoidance. Investigating the assumed epigenetic mechanisms, with reduced interpretational ambiguity and enhanced translational value in this assay, may help improve understanding of personality type-dependent susceptibility and resilience to neuropsychiatric disorders such as PTSD.

  1. Genotype-dependent consequences of traumatic stress in four inbred mouse strains.

    Science.gov (United States)

    Szklarczyk, K; Korostynski, M; Golda, S; Solecki, W; Przewlocki, R

    2012-11-01

    Post-traumatic stress disorder (PTSD) is an anxiety disorder that develops in predisposed individuals following a terrifying event. Studies on isogenic animal populations might explain susceptibility to PTSD by revealing associations between the molecular and behavioural consequences of traumatic stress. Our study employed four inbred mouse strains to search for differences in post-stress response to a 1.5-mA electric foot shock. One day to 6 weeks after the foot shock anxiety, depression and addiction-like phenotypes were assessed. In addition, expression levels of selected stress-related genes were analysed in hippocampus and amygdala. C57BL/6J mice exhibited up-regulation in the expression of Tsc22d3, Nfkbia, Plat and Crhr1 genes in both brain regions. These alterations were associated with an increase of sensitized fear and depressive-like behaviour over time. Traumatic stress induced expression of Tsc22d3, Nfkbia, Plat and Fkbp5 genes and developed social withdrawal in DBA/2J mice. In 129P3/J strain, exposure to stress produced the up-regulation of Tsc22d3 and Nfkbia genes and enhanced sensitivity to the rewarding properties of morphine. Whereas, SWR/J mice displayed increase only in Pdyn expression in the amygdala and had the lowest conditioned fear. Our results reveal a complex genetic background of phenotypic variation in response to stress and indicate the SWR/J strain as a valuable model of stress resistance. We found potential links between the alterations in expression of Tsc22d3, Nfkbia and Pdyn, and different aspects of susceptibility to stress. © 2012 The Authors. Genes, Brain and Behavior © 2012 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

  2. High-throughput behavioral phenotyping of drug and alcohol susceptibility traits in the expanded panel of BXD recombinant inbred strains

    Energy Technology Data Exchange (ETDEWEB)

    Philip, Vivek M [ORNL; Ansah, T [University of Tennessee Health Science Center, Memphis; Blaha, C, [University of Tennessee Health Science Center, Memphis; Cook, Melloni N. [University of Memphis; Hamre, Kristin M. [University of Tennessee Health Science Center, Memphis; Lariviere, William R [University of Pittsburgh; Matthews, Douglas B [Baylor University; Goldowitz, Daniel [University of British Columbia, Vancouver; Chesler, Elissa J [ORNL

    2010-01-01

    Genetic reference populations, particularly the BXD recombinant inbred strains, are a valuable resource for the discovery of the bio-molecular substrates and genetic drivers responsible for trait variation and co- ariation. This approach can be profitably applied in the analysis of susceptibility and mechanisms of drug and alcohol use disorders for which many predisposing behaviors may predict occurrence and manifestation of increased preference for these substances. Many of these traits are modeled by common mouse behavioral assays, facilitating the detection of patterns and sources of genetic co-regulation of predisposing phenotypes and substance consumption. Members of the Tennessee Mouse Genome Consortium have obtained behavioral phenotype data from 260 measures related to multiple behavioral assays across several domains: self-administration, response to, and withdrawal from cocaine, MDMA, morphine and alcohol; novelty seeking; behavioral despair and related neurological phenomena; pain sensitivity; stress sensitivity; anxiety; hyperactivity; and sleep/wake cycles. All traits have been measured in both sexes and the recently expanded panel of 69 additional BXD recombinant inbred strains (N=69). Sex differences and heritability estimates were obtained for each trait, and a comparison of early (N = 32) and recent BXD RI lines was performed. Primary data is publicly available for heritability, sex difference and genetic analyses using www.GeneNetwork.org. These analyses include QTL detection and genetic analysis of gene expression. Stored results from these analyses are available at http://ontologicaldiscovery.org for comparison to other genomic analysis results. Together with the results of related studies, these data form a public resource for integrative systems genetic analysis of neurobehavioral traits.

  3. An improved procedure of mapping a quantitative trait locus via the ...

    Indian Academy of Sciences (India)

    orders (e.g. hypertension, diabetes) are inherently quantita- tive in nature. Therefore, QTL mapping is of considerable interest in human genetics. Many currently used QTL mapping methods, especially those that have been devel- oped in the context of plant genetics or genetics of inbred animals, assume knowledge of ...

  4. A Multidisciplinary Phenotyping and Genotyping Analysis of a Mapping Population Enables Quality to Be Combined with Yield in Rice

    Directory of Open Access Journals (Sweden)

    Mariafe Calingacion

    2017-05-01

    Full Text Available In this study a mapping population (F8 of ca 200 progeny from a cross between the commercial rice varieties Apo and IR64 has been both genotyped and phenotyped. A genotyping-by-sequencing approach was first used to identify 2,681 polymorphic SNP markers which gave dense coverage of the genome with a good distribution across all 12 chromosomes. The coefficient of parentage was also low, at 0.13, confirming that the parents are genetically distant from each other. The progeny, together with both parents, were grown under irrigated and water restricted conditions in a randomised block design. All grain was harvested to determine variation in yield across the population. The grains were then polished following standard procedures prior to performing the phenotyping analyses. A Gas Chromatography—Mass Spectrometry approach was used to determine the volatile biochemical profiles of each line and after data curation and processing, discriminatory metabolites were putatively identified based on in-house and commercial spectral libraries. These data were used to predict the potential role of these metabolites in determining differences in aroma between genotypes. A number of QTLs for yield and for individual metabolites have been identified. Following these combined multi-disciplinary analyses, it proved possible to identify a number of lines which appeared to combine the favourable aroma attributes of IR64 with the favourable (higher yield potential of Apo. As such, these lines are excellent candidates to assess further as potential genotypes to work up into a new variety of rice which has both good yield and good quality, thus meeting the needs of both farmer and consumer alike.

  5. Extensive linkage disequilibrium mapping at HTR2A and DRD3 for schizophrenia susceptibility genes in the Galician population.

    Science.gov (United States)

    Domínguez, Eduardo; Loza, María Isabel; Padín, Fernando; Gesteira, Alejandro; Paz, Eduardo; Páramo, Mario; Brenlla, Julio; Pumar, Estefanía; Iglesias, Fernanda; Cibeira, Alcira; Castro, Marián; Caruncho, Héctor; Carracedo, Angel; Costas, Javier

    2007-02-01

    The serotonin and dopamine neurotransmitter systems are candidate pathways in the development of schizophrenia because of the assumed causal relationship with the observed symptoms as well as effective targeting of the corresponding receptors by antipsychotic drugs. However, genetic association studies have systematically focused on a limited set of genes and single nucleotide polymorphisms (SNPs), including T102C at HTR2A and Ser9Gly at DRD3. Meta-analyses of the associations between these two markers and schizophrenia revealed a true increase in risk, the magnitude of the effect being very low. In the present study we analyzed 260 schizophrenic patients and 354 control subjects from a homogeneous population, the Galician population, using an extensive linkage disequilibrium (LD) mapping approach, genotyping a total of 47 SNPs to test for the existence of additional variants that confer higher risk. We detected nominal significant association with schizophrenia for several haplotype tag SNPs (htSNPs) at HTR2A, although the significance was lost after multiple test corrections. In addition, haplotype analyses involving a sliding window approach, with window size 2 to 4 SNPs, revealed significant differences in frequencies of the DRD3 haplotypes at the 3' half of the gene region. This difference, which remains clearly significant after multiple test corrections (p=0.002, 0.0001, and 0.0025, for window sizes 2, 3, and 4, respectively), was mainly due to over-representation of several rare haplotypes in patients, at the expense of a single common haplotype; this represents interesting evidence of rare haplotypes for susceptibility detected using common htSNPs due to their strong effect.

  6. LA-ICP-MS trace element mapping: insights into the crystallisation history of a metamorphic garnet population

    Science.gov (United States)

    George, Freya; Gaidies, Fred

    2017-04-01

    In comparison to our understanding of major element zoning, relatively little is known about the incorporation of trace elements into metamorphic garnet. Given their extremely slow diffusivities and sensitivity to changing mineral assemblages, the analysis of the distribution of trace elements in garnet has the potential to yield a wealth of information pertaining to interfacial attachment mechanisms during garnet crystallisation, the mobility of trace elements in both garnet and the matrix, and trace element geochronology. Due to advances in the spatial resolution and analytical precision of modern microbeam techniques, small-scale trace element variations can increasingly be documented and used to inform models of metamorphic crystallisation. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) in particular, can be used to rapidly quantify a wide range of elemental masses as a series of laser rasters, producing large volumes of spatially constrained trace element data. In this study, we present LA-ICP-MS maps of trace element concentrations from numerous centrally-sectioned garnets representative of the crystal size-distribution of a single sample's population. The study sample originates from the garnet-grade Barrovian zone of the Lesser Himalayan Sequence in Sikkim, northeast India, and has been shown to have crystallised garnet within a single assemblage between 515 ˚C and 565˚C, with no evidence for accessory phase reaction over the duration of garnet growth. Previous models have indicated that the duration of garnet crystallisation was extremely rapid (growth. In spite of straightforward (i.e. concentrically-zoned) major element garnet zonation, trace elements maps are characterised by significant complexity and variability. Y and the heavy rare earth elements are strongly enriched in crystal cores, where there is overprinting of the observed internal fabric, and exhibit numerous concentric annuli towards crystal rims. Conversely, the

  7. Mapping the Centimeter-Scale Spatial Variability of PAHs and Microbial Populations in the Rhizosphere of Two Plants.

    Directory of Open Access Journals (Sweden)

    Amélia Bourceret

    Full Text Available Rhizoremediation uses root development and exudation to favor microbial activity. Thus it can enhance polycyclic aromatic hydrocarbon (PAH biodegradation in contaminated soils. Spatial heterogeneity of rhizosphere processes, mainly linked to the root development stage and to the plant species, could explain the contrasted rhizoremediation efficiency levels reported in the literature. Aim of the present study was to test if spatial variability in the whole plant rhizosphere, explored at the centimetre-scale, would influence the abundance of microorganisms (bacteria and fungi, and the abundance and activity of PAH-degrading bacteria, leading to spatial variability in PAH concentrations. Two contrasted rhizospheres were compared after 37 days of alfalfa or ryegrass growth in independent rhizotron devices. Almost all spiked PAHs were degraded, and the density of the PAH-degrading bacterial populations increased in both rhizospheres during the incubation period. Mapping of multiparametric data through geostatistical estimation (kriging revealed that although root biomass was spatially structured, PAH distribution was not. However a greater variability of the PAH content was observed in the rhizosphere of alfalfa. Yet, in the ryegrass-planted rhizotron, the Gram-positive PAH-degraders followed a reverse depth gradient to root biomass, but were positively correlated to the soil pH and carbohydrate concentrations. The two rhizospheres structured the microbial community differently: a fungus-to-bacterium depth gradient similar to the root biomass gradient only formed in the alfalfa rhizotron.

  8. Gene-based SNP discovery and genetic mapping in pea.

    Science.gov (United States)

    Sindhu, Anoop; Ramsay, Larissa; Sanderson, Lacey-Anne; Stonehouse, Robert; Li, Rong; Condie, Janet; Shunmugam, Arun S K; Liu, Yong; Jha, Ambuj B; Diapari, Marwan; Burstin, Judith; Aubert, Gregoire; Tar'an, Bunyamin; Bett, Kirstin E; Warkentin, Thomas D; Sharpe, Andrew G

    2014-10-01

    Gene-based SNPs were identified and mapped in pea using five recombinant inbred line populations segregating for traits of agronomic importance. Pea (Pisum sativum L.) is one of the world's oldest domesticated crops and has been a model system in plant biology and genetics since the work of Gregor Mendel. Pea is the second most widely grown pulse crop in the world following common bean. The importance of pea as a food crop is growing due to its combination of moderate protein concentration, slowly digestible starch, high dietary fiber concentration, and its richness in micronutrients; however, pea has lagged behind other major crops in harnessing recent advances in molecular biology, genomics and bioinformatics, partly due to its large genome size with a large proportion of repetitive sequence, and to the relatively limited investment in research in this crop globally. The objective of this research was the development of a genome-wide transcriptome-based pea single-nucleotide polymorphism (SNP) marker platform using next-generation sequencing technology. A total of 1,536 polymorphic SNP loci selected from over 20,000 non-redundant SNPs identified using deep transcriptome sequencing of eight diverse Pisum accessions were used for genotyping in five RIL populations using an Illumina GoldenGate assay. The first high-density pea SNP map defining all seven linkage groups was generated by integrating with previously published anchor markers. Syntenic relationships of this map with the model legume Medicago truncatula and lentil (Lens culinaris Medik.) maps were established. The genic SNP map establishes a foundation for future molecular breeding efforts by enabling both the identification and tracking of introgression of genomic regions harbouring QTLs related to agronomic and seed quality traits.

  9. Genome-wide association mapping for yield and other agronomic traits in an elite breeding population of tropical rice (Oryza sativa).

    Science.gov (United States)

    Begum, Hasina; Spindel, Jennifer E; Lalusin, Antonio; Borromeo, Teresita; Gregorio, Glenn; Hernandez, Jose; Virk, Parminder; Collard, Bertrand; McCouch, Susan R

    2015-01-01

    Genome-wide association mapping studies (GWAS) are frequently used to detect QTL in diverse collections of crop germplasm, based on historic recombination events and linkage disequilibrium across the genome. Generally, diversity panels genotyped with high density SNP panels are utilized in order to assay a wide range of alleles and haplotypes and to monitor recombination breakpoints across the genome. By contrast, GWAS have not generally been performed in breeding populations. In this study we performed association mapping for 19 agronomic traits including yield and yield components in a breeding population of elite irrigated tropical rice breeding lines so that the results would be more directly applicable to breeding than those from a diversity panel. The population was genotyped with 71,710 SNPs using genotyping-by-sequencing (GBS), and GWAS performed with the explicit goal of expediting selection in the breeding program. Using this breeding panel we identified 52 QTL for 11 agronomic traits, including large effect QTLs for flowering time and grain length/grain width/grain-length-breadth ratio. We also identified haplotypes that can be used to select plants in our population for short stature (plant height), early flowering time, and high yield, and thus demonstrate the utility of association mapping in breeding populations for informing breeding decisions. We conclude by exploring how the newly identified significant SNPs and insights into the genetic architecture of these quantitative traits can be leveraged to build genomic-assisted selection models.

  10. Determination of the Heterotic groups of Maize inbred lines and the ...

    African Journals Online (AJOL)

    Maize weevil (Sitophilus zeamais Motschulsky) is a major maize (Zea mays L) storage insect pest in the tropics. Fifty-two inbred lines developed for weevil resistance were crossed to two testers, A and B, to determine their heterotic groups and inheritance of resistance to maize weevil. For 10 testcrosses selected for ...

  11. [Systematically induced effects of Tetranychus cinnabarinus infestation on chemical defense in Zea mays inbred lines].

    Science.gov (United States)

    Zhu, Yu-xi; Yang, Qun-fang; Huang, Yu-bi; Li, Qing

    2015-09-01

    In the present study, we investigated the systematically induced production of defense-related compounds, including DIMBOA, total phenol, trypsin inhibitors (TI) and chymotrypsin inhibitor (CI), by Tetranychus cinnabarinus infestation in Zea mays. The first leaves of two corn in-bred line seedlings, the mite-tolerant line ' H1014168' and the mite-sensitive line 'H1014591', were sucked by T. cinnabarinus adult female for seven days, and then the contents of DIMBOA, total phenol, TI and CI were measured in the second leaf and in the roots, respectively. Results showed that as compared to the unsucked control, all contents of DIMBOA, total phenol, TI and CI induced by T. cinnabarinus sucking were significantly higher in the second leaf of both inbred lines as well as in the roots of the mite-tolerant 'H1014168'. However, in the roots of 'H1014591', these defense compounds had different trends, where there was a higher induction of TI and a lower level of total phenol than that of the healthy control, while had almost no difference in DIMBOA and CI. These findings suggested that the infestation of T. cinnabarinus could systematically induce accumulation of defense-related compounds, and this effect was stronger in the mite-tolerant inbred line than in the mite-sensitive inbred line.

  12. Characterization of phenylpropanoid pathway genes within European maize (Zea mays L.) inbreds

    DEFF Research Database (Denmark)

    Andersen, Jeppe Reitan; Zein, Imad; Wenzel, Gerhard

    2008-01-01

    genomic fragments of six putative phenylpropanoid pathway genes in a panel of elite European inbred lines of maize (Zea mays L.) contrasting in forage quality traits. Six loci, encoding C4H, 4CL1, 4CL2, C3H, F5H, and CAD, displayed different levels of nucleotide diversity and linkage disequilibrium (LD...

  13. TEMPORAL STRUCTURE OF OPEN-FIELD BEHAVIOR IN INBRED STRAINS OF MICE

    NARCIS (Netherlands)

    MAKINO, J; KATO, K; MAES, FW

    1991-01-01

    Behavior of the inbred mouse strains BALB, C3H, DBA and C57BL in an open field was directly observed for 10 min by a multi-event time sampling method. It was coded into nine behavioral items, the occurrence or absence of which in consecutive 5-s time bins was called a behavioral state. Fourteen

  14. Doubled haploid inbred lines USVL048 and USVL131 of heading broccoli

    Science.gov (United States)

    Two inbred lines of heading broccoli (Brassica oleracea L. var. italica), designated USVL048 and USVL131, were released by the Agricultural Research Service of the U.S. Department of Agriculture in 2012. Both of the released lines are doubled haploids originally derived from another culture. As do...

  15. Estimation of genetic variability level in inbred CF1 mouse lines ...

    Indian Academy of Sciences (India)

    3Cátedra de Producción de Bovinos para carne, Facultad de Ciencias Veterinarias, CIC, Universidad Nacional de Rosario,. Argentina, Ov. Lagos y Ruta 33 (2170) Casilda, Argentina. [Renny M., Julio N. B., Bernardi S. F., Gardenal C. N. and Oyarzabal M. I. 2014 Estimation of genetic variability level in inbred CF1 mouse.

  16. Combining ability of maize ( Zea mays L.) inbred lines resistant to ...

    African Journals Online (AJOL)

    Ten inbred parents with varying resistance levels to Chilo partellus and Busseola fusca were crossed in a half diallel mating scheme to generate 45 F1 hybrids. The hybrids and five commercial checks were evaluated across four locations in Kenya under artificial and natural infestation in 2009. Genotype (G) by environment ...

  17. Study of yield and yield components of corn ( Zea mays L.) inbred ...

    African Journals Online (AJOL)

    In order to study the effects of drought stress on yield and yield components of seven corn inbred lines, a field trial was conducted under non-stress and different drought stress conditions (stress at vegetative (6 to 7 leaves), pollination and grain filling stages) at the Agricultural College of Islamic Azad University, Shoushtar ...

  18. USDA 846-1 fractal melon and derived recombinant inbred lines

    Science.gov (United States)

    The Agricultural Research Service, United States Department of Agriculture announces the release of a melon (Cucumis melo L.) breeding line with highly branched, fractal-type architectural growth habit and 81 derived recombinant inbred lines (RIL). The indeterminate, monoecious USDA 846-1 produces 2...

  19. DFT study on the mechanism of InBr3-catalyzed [2+2] cycloaddition ...

    Indian Academy of Sciences (India)

    chemsci

    Abstract. Density functional theory calculations at the M06-2X level were done to study the reaction mech- anism and regioselectivity for the [2+2] cycloaddition of allyltrimethylsilane with alkynones using InBr3 as the catalyst. The solvent effect was described by the single-point calculations with SMD model in 1,2-.

  20. A Multiparent Advanced Generation Inter-Cross to fine-map quantitative traits in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Paula X Kover

    2009-07-01

    Full Text Available Identifying natural allelic variation that underlies quantitative trait variation remains a fundamental problem in genetics. Most studies have employed either simple synthetic populations with restricted allelic variation or performed association mapping on a sample of naturally occurring haplotypes. Both of these approaches have some limitations, therefore alternative resources for the genetic dissection of complex traits continue to be sought. Here we describe one such alternative, the Multiparent Advanced Generation Inter-Cross (MAGIC. This approach is expected to improve the precision with which QTL can be mapped, improving the outlook for QTL cloning. Here, we present the first panel of MAGIC lines developed: a set of 527 recombinant inbred lines (RILs descended from a heterogeneous stock of 19 intermated accessions of the plant Arabidopsis thaliana. These lines and the 19 founders were genotyped with 1,260 single nucleotide polymorphisms and phenotyped for development-related traits. Analytical methods were developed to fine-map quantitative trait loci (QTL in the MAGIC lines by reconstructing the genome of each line as a mosaic of the founders. We show by simulation that QTL explaining 10% of the phenotypic variance will be detected in most situations with an average mapping error of about 300 kb, and that if the number of lines were doubled the mapping error would be under 200 kb. We also show how the power to detect a QTL and the mapping accuracy vary, depending on QTL location. We demonstrate the utility of this new mapping population by mapping several known QTL with high precision and by finding novel QTL for germination data and bolting time. Our results provide strong support for similar ongoing efforts to produce MAGIC lines in other organisms.

  1. Rice genome mapping and its application in rice genetics and breeding

    International Nuclear Information System (INIS)

    Eun, M.Y.; Cho, Y.G.; Hahn, J.H.; Yoon, U.H.; Yi, B.Y.; Chung, T.Y.

    1998-01-01

    An 'MG' recombinant inbred population which consists of 164 F 13 lines has been developed from a cross between a Tongil type variety Milyang 23 and a Japonica type Gihobyeo by single seed descent. A Restriction Fragment Length Polymorphism (RFLP) framework map using this population has been constructed. Morphological markers, isozyme loci, microsatellites, Amplified Fragment Length Polymorphisms (AFLP), and new complementary DNA (cDNA) markers are being integrated in the framework map for a highly saturated comprehensive map. So far, 207 RFLPs, 89 microsatellites, 5 isozymes, 232 AFLPs, and 2 morphological markers have been mapped through international collaboration. The map contains 1,826 cM with an average interval size of 4.5 cM on the framework map and 3.4 cM overall (as of 29 October 1996). The framework map is being used for analyzing, quantitative trait loci (QTL) of agronomic characters and some physico-chemical properties relating to rice quality. The number of significant QTLs affecting each trait ranged from one to five, and 38 QTLs were detected for 17 traits. The percentage of variance explained by each QTL ranged from 5.6 to 66.9%. The isozyme marker, EstI-2, and two RFLP markers, RG109 and RG220, were linked most tightly at a distance less than 1 cM with the semidwarf (sd-1) gene on chromosome 1. These markers could be used for precise in vitro selection of individuals carrying the semidwarf gene using single seeds or very young leaf tissue, before this character is fully expressed. Appropriate application of marker-assisted selection, using EstI-2 and RFLP markers for the semidwarf character, in combination with other markers linked to genes of agronomic importance in rice, holds promise for improving, the efficiency of breeding, and the high-resolution genetic and physical mapping near sd-1, aimed at ultimately cloning this valuable gene

  2. A high-density SNP map for accurate mapping of seed fibre QTL in Brassica napus L.

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    Liezhao Liu

    Full Text Available A high density genetic linkage map for the complex allotetraploid crop species Brassica napus (oilseed rape was constructed in a late-generation recombinant inbred line (RIL population, using genome-wide single nucleotide polymorphism (SNP markers assayed by the Brassica 60 K Infinium BeadChip Array. The linkage map contains 9164 SNP markers covering 1832.9 cM. 1232 bins account for 7648 of the markers. A subset of 2795 SNP markers, with an average distance of 0.66 cM between adjacent markers, was applied for QTL mapping of seed colour and the cell wall fiber components acid detergent lignin (ADL, cellulose and hemicellulose. After phenotypic analyses across four different environments a total of 11 QTL were detected for seed colour and fiber traits. The high-density map considerably improved QTL resolution compared to the previous low-density maps. A previously identified major QTL with very high effects on seed colour and ADL was pinpointed to a narrow genome interval on chromosome A09, while a minor QTL explaining 8.1% to 14.1% of variation for ADL was detected on chromosome C05. Five and three QTL accounting for 4.7% to 21.9% and 7.3% to 16.9% of the phenotypic variation for cellulose and hemicellulose, respectively, were also detected. To our knowledge this is the first description of QTL for seed cellulose and hemicellulose in B. napus, representing interesting new targets for improving oil content. The high density SNP genetic map enables navigation from interesting B. napus QTL to Brassica genome sequences, giving useful new information for understanding the genetics of key seed quality traits in rapeseed.

  3. Genetic Architecture of Atherosclerosis in Mice: A Systems Genetics Analysis of Common Inbred Strains

    Science.gov (United States)

    Bennett, Brian J.; Davis, Richard C.; Civelek, Mete; Orozco, Luz; Wu, Judy; Qi, Hannah; Pan, Calvin; Packard, René R. Sevag; Eskin, Eleazar; Yan, Mujing; Kirchgessner, Todd; Wang, Zeneng; Li, Xinmin; Gregory, Jill C.; Hazen, Stanley L.; Gargalovic, Peter S.; Lusis, Aldons J.

    2015-01-01

    Common forms of atherosclerosis involve multiple genetic and environmental factors. While human genome-wide association studies have identified numerous loci contributing to coronary artery disease and its risk factors, these studies are unable to control environmental factors or examine detailed molecular traits in relevant tissues. We now report a study of natural variations contributing to atherosclerosis and related traits in over 100 inbred strains of mice from the Hybrid Mouse Diversity Panel (HMDP). The mice were made hyperlipidemic by transgenic expression of human apolipoprotein E-Leiden (APOE-Leiden) and human cholesteryl ester transfer protein (CETP). The mice were examined for lesion size and morphology as well as plasma lipid, insulin and glucose levels, and blood cell profiles. A subset of mice was studied for plasma levels of metabolites and cytokines. We also measured global transcript levels in aorta and liver. Finally, the uptake of acetylated LDL by macrophages from HMDP mice was quantitatively examined. Loci contributing to the traits were mapped using association analysis, and relationships among traits were examined using correlation and statistical modeling. A number of conclusions emerged. First, relationships among atherosclerosis and the risk factors in mice resemble those found in humans. Second, a number of trait-loci were identified, including some overlapping with previous human and mouse studies. Third, gene expression data enabled enrichment analysis of pathways contributing to atherosclerosis and prioritization of candidate genes at associated loci in both mice and humans. Fourth, the data provided a number of mechanistic inferences; for example, we detected no association between macrophage uptake of acetylated LDL and atherosclerosis. Fifth, broad sense heritability for atherosclerosis was much larger than narrow sense heritability, indicating an important role for gene-by-gene interactions. Sixth, stepwise linear regression

  4. Genetic Architecture of Atherosclerosis in Mice: A Systems Genetics Analysis of Common Inbred Strains.

    Directory of Open Access Journals (Sweden)

    Brian J Bennett

    2015-12-01

    Full Text Available Common forms of atherosclerosis involve multiple genetic and environmental factors. While human genome-wide association studies have identified numerous loci contributing to coronary artery disease and its risk factors, these studies are unable to control environmental factors or examine detailed molecular traits in relevant tissues. We now report a study of natural variations contributing to atherosclerosis and related traits in over 100 inbred strains of mice from the Hybrid Mouse Diversity Panel (HMDP. The mice were made hyperlipidemic by transgenic expression of human apolipoprotein E-Leiden (APOE-Leiden and human cholesteryl ester transfer protein (CETP. The mice were examined for lesion size and morphology as well as plasma lipid, insulin and glucose levels, and blood cell profiles. A subset of mice was studied for plasma levels of metabolites and cytokines. We also measured global transcript levels in aorta and liver. Finally, the uptake of acetylated LDL by macrophages from HMDP mice was quantitatively examined. Loci contributing to the traits were mapped using association analysis, and relationships among traits were examined using correlation and statistical modeling. A number of conclusions emerged. First, relationships among atherosclerosis and the risk factors in mice resemble those found in humans. Second, a number of trait-loci were identified, including some overlapping with previous human and mouse studies. Third, gene expression data enabled enrichment analysis of pathways contributing to atherosclerosis and prioritization of candidate genes at associated loci in both mice and humans. Fourth, the data provided a number of mechanistic inferences; for example, we detected no association between macrophage uptake of acetylated LDL and atherosclerosis. Fifth, broad sense heritability for atherosclerosis was much larger than narrow sense heritability, indicating an important role for gene-by-gene interactions. Sixth, stepwise linear

  5. Mapping QTLs Controlling Flowering Time and Important Agronomic Traits in Pearl Millet.

    Science.gov (United States)

    Kumar, Sushil; Hash, C Tom; Nepolean, T; Satyavathi, C Tara; Singh, Govind; Mahendrakar, Mahesh D; Yadav, Rattan S; Srivastava, Rakesh K

    2017-01-01

    Pearl millet [ Pennisetum glaucum (L.) R. Br.] is a staple crop for the people of arid and semi-arid regions of the world. It is fast gaining importance as a climate resilient nutricereal. Exploiting the bold seeded, semi-dwarf, and early flowering genotypes in pearl millet is a key breeding strategy to enhance yield, adaptability, and for adequate food in resource-poor zones. Genetic variation for agronomic traits of pearl millet inbreds can be used to dissect complex traits through quantitative trait locus (QTL) mapping. This study was undertaken to map a set of agronomically important traits like flowering time (FT), plant height (PH), panicle length (PL), and grain weight (self and open-pollinated seeds) in the recombinant inbred line (RIL) population of ICMB 841-P3 × 863B-P2 cross. Excluding grain weight (open pollinated), heritabilities for FT, PH, PL, grain weight (selfed) were in high to medium range. A total of six QTLs for FT were detected on five chromosomes, 13 QTLs for PH on six chromosomes, 11 QTLs for PL on five chromosomes, and 14 QTLs for 1,000-grain weight (TGW) spanning five chromosomes. One major QTL on LG3 was common for FT and PH. Three major QTLs for PL, one each on LG1, LG2, and LG6B were detected. The large effect QTL for TGW (self) on LG6B had a phenotypic variance ( R 2 ) of 62.1%. The R 2 for FT, TGW (self), and PL ranged from 22.3 to 59.4%. A total of 21 digenic interactions were discovered for FT ( R 2 = 18-40%) and PL ( R 2 = 13-19%). The epistatic effects did not reveal any significant QTL × QTL × environment (QQE) interactions. The mapped QTLs for flowering time and other agronomic traits in present experiment can be used for marker-assisted selection (MAS) and genomic selection (GS) breeding programs.

  6. Complementation contributes to transcriptome complexity in maize (Zea mays L.) hybrids relative to their inbred parents

    Science.gov (United States)

    Paschold, Anja; Jia, Yi; Marcon, Caroline; Lund, Steve; Larson, Nick B.; Yeh, Cheng-Ting; Ossowski, Stephan; Lanz, Christa; Nettleton, Dan; Schnable, Patrick S.; Hochholdinger, Frank

    2012-01-01

    Typically, F1-hybrids are more vigorous than their homozygous, genetically distinct parents, a phenomenon known as heterosis. In the present study, the transcriptomes of the reciprocal maize (Zea mays L.) hybrids B73×Mo17 and Mo17×B73 and their parental inbred lines B73 and Mo17 were surveyed in primary roots, early in the developmental manifestation of heterotic root traits. The application of statistical methods and a suitable experimental design established that 34,233 (i.e., 86%) of all high-confidence maize genes were expressed in at least one genotype. Nearly 70% of all expressed genes were differentially expressed between the two parents and 42%–55% of expressed genes were differentially expressed between one of the parents and one of the hybrids. In both hybrids, ∼10% of expressed genes exhibited nonadditive gene expression. Consistent with the dominance model (i.e., complementation) for heterosis, 1124 genes that were expressed in the hybrids were expressed in only one of the two parents. For 65 genes, it could be shown that this was a consequence of complementation of genomic presence/absence variation. For dozens of other genes, alleles from the inactive inbred were activated in the hybrid, presumably via interactions with regulatory factors from the active inbred. As a consequence of these types of complementation, both hybrids expressed more genes than did either parental inbred. Finally, in hybrids, ∼14% of expressed genes exhibited allele-specific expression (ASE) levels that differed significantly from the parental-inbred expression ratios, providing further evidence for interactions of regulatory factors from one parental genome with target genes from the other parental genome. PMID:23086286

  7. Development of genetic markers linked to straighthead resistance through fine mapping in rice (Oryza sativa L..

    Directory of Open Access Journals (Sweden)

    Xuhao Pan

    Full Text Available Straighthead, a physiological disorder characterized by sterile florets and distorted spikelets, causes significant yield losses in rice, and occurs in many countries. The current control method of draining paddies early in the season stresses plants, is costly, and wastes water. Development of resistant cultivar is regarded as the most efficient way for its control. We mapped a QTL for straighthead resistance using two recombinant inbred line (RIL F(9 populations that were phenotyped over two years using monosodium methanearsonate (MSMA to induce the symptoms. One population of 170 RILs was genotyped with 136 SSRs and the other population of 91 RILs was genotyped with 159 SSRs. A major QTL qSH-8 was identified in an overlapping region in both populations, and explained 46% of total variation in one and 67% in another population for straighthead resistance. qSH-8 was fine mapped from 1.0 Mbp to 340 kb using 7 SSR markers and further mapped to 290 kb in a population between RM22573 and InDel 27 using 4 InDel markers. SSR AP3858-1 and InDel 11 were within the fine mapped region, and co-segregated with straighthead resistance in both RIL populations, as well as in a collection of diverse global accessions. These results demonstrate that AP3858-1 and InDel 11 can be used for marker-assisted selection (MAS for straighthead resistant cultivars, which is especially important because there is no effective way to directly evaluate straighthead resistance.

  8. Visual cortex in aging and Alzheimer’s disease: Changes in visual field maps and population receptive fields

    Directory of Open Access Journals (Sweden)

    Alyssa A. Brewer

    2014-02-01

    Full Text Available Although several studies have suggested that cortical alterations underlie such age-related visual deficits as decreased acuity, little is known about what changes actually occur in visual cortex during healthy aging. Two recent studies showed changes in primary visual cortex (V1 during normal aging; however, no studies have characterized the effects of aging on visual cortex beyond V1, important measurements both for understanding the aging process and for comparison to changes in age-related diseases. Similarly, there is almost no information about changes in visual cortex in Alzheimer’s disease (AD, the most common form of dementia. Because visual deficits are often reported as one of the first symptoms of AD, measurements of such changes in the visual cortex of AD patients might improve our understanding of how the visual system is affected by neurodegeneration as well as aid early detection, accurate diagnosis and timely treatment of AD. Here we use fMRI to first compare the visual field map (VFM organization and population receptive fields (pRFs between young adults and healthy aging subjects for occipital VFMs V1, V2, V3, and hV4. Healthy aging subjects do not show major VFM organizational deficits, but do have reduced surface area and increased pRF sizes in the foveal representations of V1, V2, and hV4 relative to healthy young control subjects. These measurements are consistent with behavioral deficits seen in healthy aging. We then demonstrate the feasibility and first characterization of these measurements in two patients with mild AD, which reveal potential changes in visual cortex as part of the pathophysiology of AD. Our data aid in our understanding of the changes in the visual processing pathways in normal aging and provide the foundation for future research into earlier and more definitive detection of AD.

  9. QTL identification of grain protein concentration and its genetic correlation with starch concentration and grain weight using two populations in maize (Zea mays L.).

    Science.gov (United States)

    Li, Yuling; Wang, Yanzhao; Wei, Mengguan; Li, Xuehui; Fu, Jiafeng

    2009-04-01

    Protein is one of the three main storage chemical components in maize grains, and is negatively correlated with starch concentration (SC). Our objective was to analyse the influence of genetic backgrounds on QTL detection for protein concentration (PC) and to reveal the molecular genetic associations between PC and both SC and grain weight (GWP). Two hundred and eighty-four (Pop1) and 265 (Pop2) F(2:3) families were developed from two crosses between one high-oil maize inbred GY220 and two normal maize inbreds 8984 and 8622 respectively, and were genotyped with 185 and 173 pairs of SSR markers. PC, SC and GWP were evaluated under two environments. Composite interval mapping (CIM) and multiple interval mapping (MIM) methods were used to detect single-trait QTL for PC, and multiple-trait QTL for PC with both SC and GWP. No common QTL were shared between the two populations for their four and one PC QTL. Common QTL with opposite signs of effects for PC and SCGWP were detected on three marker intervals at bins 6.07-6.08, 8.03 and 8.03-8.04. Multiple-traits QTL mapping showed that tightly-linked QTL, pleiotropic QTL and QTL having effects with opposite directions for PC and SCGWP were all observed in Pop1, while all QTL reflected opposite effects in Pop2.

  10. Comparative Performance of Hybrid and Elite Inbred Rice Varieties with respect to Their Source-Sink Relationship

    Directory of Open Access Journals (Sweden)

    Md Moinul Haque

    2015-01-01

    Full Text Available Hybrid rice varieties have higher yield potential over inbred varieties. This improvement is not always translated to the grain yield and its physiological causes are still unclear. In order to clarify it, two field experiments were conducted including two popular indica hybrids (BRRI hybrid dhan2 and Heera2 and one elite inbred (BRRI dhan45 rice varieties. Leaf area index, chlorophyll status, and photosynthetic rate of flag leaf, postheading crop growth rate, shoot reserve translocation, source-sink relation and yield, and its attributes of each variety were comprehensively analyzed. Both hybrid varieties outyielded the inbred. However, the hybrids and inbred varieties exhibited statistically identical yield in late planting. Both hybrids accumulated higher amount of biomass before heading and exhibited greater remobilization of assimilates to the grain in early plantings compared to the inbred variety. Filled grain (% declined significantly at delayed planting in the hybrids compared to elite inbred due to increased temperature impaired-inefficient transport of assimilates. Flag leaf photosynthesis parameters were higher in the hybrid varieties than those of the inbred variety. Results suggest that greater remobilization of shoot reserves to the grain rendered higher yield of hybrid rice varieties.

  11. Mapping of PARK2 and PACRG overlapping regulatory region reveals LD structure and functional variants in association with leprosy in unrelated indian population groups.

    Science.gov (United States)

    Chopra, Rupali; Ali, Shafat; Srivastava, Amit K; Aggarwal, Shweta; Kumar, Bhupender; Manvati, Siddharth; Kalaiarasan, Ponnusamy; Jena, Mamta; Garg, Vijay K; Bhattacharya, Sambit N; Bamezai, Rameshwar N K

    2013-01-01

    Leprosy is a chronic infectious disease caused by Mycobacterium Leprae, where the host genetic background plays an important role toward the disease pathogenesis. Various studies have identified a number of human genes in association with leprosy or its clinical forms. However, non-replication of results has hinted at the heterogeneity among associations between different population groups, which could be due to differently evolved LD structures and differential frequencies of SNPs within the studied regions of the genome. A need for systematic and saturated mapping of the associated regions with the disease is warranted to unravel the observed heterogeneity in different populations. Mapping of the PARK2 and PACRG gene regulatory region with 96 SNPs, with a resolution of 1 SNP per 1 Kb for PARK2 gene regulatory region in a North Indian population, showed an involvement of 11 SNPs in determining the susceptibility towards leprosy. The association was replicated in a geographically distinct and unrelated population from Orissa in eastern India. In vitro reporter assays revealed that the two significantly associated SNPs, located 63.8 kb upstream of PARK2 gene and represented in a single BIN of 8 SNPs, influenced the gene expression. A comparison of BINs between Indian and Vietnamese populations revealed differences in the BIN structures, explaining the heterogeneity and also the reason for non-replication of the associated genomic region in different populations.

  12. Scanning the landscape of genome architecture of non-O1 and non-O139 Vibrio cholerae by whole genome mapping reveals extensive population genetic diversity.

    Science.gov (United States)

    Chapman, Carol; Henry, Matthew; Bishop-Lilly, Kimberly A; Awosika, Joy; Briska, Adam; Ptashkin, Ryan N; Wagner, Trevor; Rajanna, Chythanya; Tsang, Hsinyi; Johnson, Shannon L; Mokashi, Vishwesh P; Chain, Patrick S G; Sozhamannan, Shanmuga

    2015-01-01

    Historically, cholera outbreaks have been linked to V. cholerae O1 serogroup strains or its derivatives of the O37 and O139 serogroups. A genomic study on the 2010 Haiti cholera outbreak strains highlighted the putative role of non O1/non-O139 V. cholerae in causing cholera and the lack of genomic sequences of such strains from around the world. Here we address these gaps by scanning a global collection of V. cholerae strains as a first step towards understanding the population genetic diversity and epidemic potential of non O1/non-O139 strains. Whole Genome Mapping (Optical Mapping) based bar coding produces a high resolution, ordered restriction map, depicting a complete view of the unique chromosomal architecture of an organism. To assess the genomic diversity of non-O1/non-O139 V. cholerae, we applied a Whole Genome Mapping strategy on a well-defined and geographically and temporally diverse strain collection, the Sakazaki serogroup type strains. Whole Genome Map data on 91 of the 206 serogroup type strains support the hypothesis that V. cholerae has an unprecedented genetic and genomic structural diversity. Interestingly, we discovered chromosomal fusions in two unusual strains that possess a single chromosome instead of the two chromosomes usually found in V. cholerae. We also found pervasive chromosomal rearrangements such as duplications and indels in many strains. The majority of Vibrio genome sequences currently in public databases are unfinished draft sequences. The Whole Genome Mapping approach presented here enables rapid screening of large strain collections to capture genomic complexities that would not have been otherwise revealed by unfinished draft genome sequencing and thus aids in assembling and finishing draft sequences of complex genomes. Furthermore, Whole Genome Mapping allows for prediction of novel V. cholerae non-O1/non-O139 strains that may have the potential to cause future cholera outbreaks.

  13. Discrimination of candidate subgenome-specific loci by linkage map construction with an S1population of octoploid strawberry (Fragaria × ananassa).

    Science.gov (United States)

    Nagano, Soichiro; Shirasawa, Kenta; Hirakawa, Hideki; Maeda, Fumi; Ishikawa, Masami; Isobe, Sachiko N

    2017-05-12

    The strawberry, Fragaria × ananassa, is an allo-octoploid (2n = 8x = 56) and outcrossing species. Although it is the most widely consumed berry crop in the world, its complex genome structure has hindered its genetic and genomic analysis, and thus discrimination of subgenome-specific loci among the homoeologous chromosomes is needed. In the present study, we identified candidate subgenome-specific single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) loci, and constructed a linkage map using an S 1 mapping population of the cultivar 'Reikou' with an IStraw90 Axiom® SNP array and previously published SSR markers. The 'Reikou' linkage map consisted of 11,574 loci (11,002 SNPs and 572 SSR loci) spanning 2816.5 cM of 31 linkage groups. The 11,574 loci were located on 4738 unique positions (bin) on the linkage map. Of the mapped loci, 8999 (8588 SNPs and 411 SSR loci) showed a 1:2:1 segregation ratio of AA:AB:BB allele, which suggested the possibility of deriving loci from candidate subgenome-specific sequences. In addition, 2575 loci (2414 SNPs and 161 SSR loci) showed a 3:1 segregation of AB:BB allele, indicating they were derived from homoeologous genomic sequences. Comparative analysis of the homoeologous linkage groups revealed differences in genome structure among the subgenomes. Our results suggest that candidate subgenome-specific loci are randomly located across the genomes, and that there are small- to large-scale structural variations among the subgenomes. The mapped SNPs and SSR loci on the linkage map are expected to be seed points for the construction of pseudomolecules in the octoploid strawberry.

  14. Genetic Map Construction and Quantitative Trait Locus (QTL Detection of Six Economic Traits Using an F2 Population of the Hybrid from Saccharina longissima and Saccharina japonica.

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    Full Text Available Saccharina (Laminaria is one of the most important economic seaweeds. Previously, four genetic linkage maps of Saccharina have been constructed and five QTLs have been identified. However, they were not enough for its breeding. In this work, Saccharina longissima (♀ and Saccharina japonica (♂, which showed obvious differences in morphology and genetics, were applied in hybridization to yield the F2 mapping population with 102 individuals. Using these 102 F2 hybrids, the genetic linkage map of Saccharina was constructed by MapMaker software based on 37 amplified fragment length polymorphisms (AFLPs, 22 sequence-related amplified polymorphisms (SRAPs and 139 simple sequence repeats (SSRs markers. Meanwhile, QTL analysis was performed for six economic traits. The linkage map constructed in this research consisted of 422 marker loci (137 AFLPs, 57 SRAPs and 228 SSRs, which formed 45 linkage groups (LGs with an average marker space of 7.92 cM; they spanned a total length of 2233.1 cM, covering the whole estimated genome size. A total of 29 QTLs were identified for six economic traits, which explained 1.06 to 64.00% of phenotypic variation, including three QTLs for frond length (FL and raw weight (RW, five QTLs for frond width (FW, two QTLs for frond fascia width (FFW and frond thickness (FT, and fourteen QTLs for base shape (BS. The results of this research will improve the breeding efficiency and be beneficial for marker-assisted selection (MAS schemes in Saccharina breeding.

  15. Genetic diversity for restriction fragment length polymorphisms and heterosis for two diallel sets of maize inbreds.

    Science.gov (United States)

    Melchinger, A E; Lee, M; Lamkey, K R; Hallauer, A R; Woodman, W L

    1990-10-01

    Changes that may have occurred over the past 50 years of hybrid breeding in maize (Zea maize L.) with respect to heterosis for yield and heterozygosity at the molecular level are of interest to both maize breeders and quantitative geneticists. The objectives of this study were twofold: The first, to compare two diallels produced from six older maize inbreds released in the 1950's and earlier and six newer inbreds released during the 1970's with respect to (a) genetic variation for restriction fragment length polymorphisms (RFLPs) and (b) the size of heterosis and epistatic effects, and the second, to evaluate the usefulness of RFLP-based genetic distance measures in predicting heterosis and performance of single-cross hybrids. Five generations (parents, F1; F2, and backcrosses) from the 15 crosses in each diallel were evaluated for grain yield and yield components in four Iowa environments. Genetic effects were estimated from generation means by ordinary diallel analyses and by the Eberhart-Gardner model. Newer lines showed significantly greater yield for inbred generations than did older lines but smaller heterosis estimates. In most cases, estimates of additive x additive epistatic effects for yield and yield components were significantly positive for both groups of lines. RFLP analyses of inbred lines included two restriction enzymes and 82 genomic DNA clones distributed over the maize genome. Eighty-one clones revealed polymorphisms with at least one enzyme. In each set, about three different RFLP variants were typically found per RFLP locus. Genetic distances between inbred lines were estimated from RFLP data as Rogers' distance (RD), which was subdivided into general (GRD) and specific (SRD) Rogers' distances within each diallel. The mean and range of RDs were similar for the older and newer lines, suggesting that the level of heterozygosity at the molecular level had not changed. GRD explained about 50% of the variation among RD values in both sets. Cluster

  16. Identification of candidate genes involved in Witches' broom disease resistance in a segregating mapping population of Theobroma cacao L. in Brazil.

    Science.gov (United States)

    Royaert, Stefan; Jansen, Johannes; da Silva, Daniela Viana; de Jesus Branco, Samuel Martins; Livingstone, Donald S; Mustiga, Guiliana; Marelli, Jean-Philippe; Araújo, Ioná Santos; Corrêa, Ronan Xavier; Motamayor, Juan Carlos

    2016-02-11

    Witches' broom disease (WBD) caused by the fungus Moniliophthora perniciosa is responsible for considerable economic losses for cacao producers. One of the ways to combat WBD is to plant resistant cultivars. Resistance may be governed by a few genetic factors, mainly found in wild germplasm. We developed a dense genetic linkage map with a length of 852.8 cM that contains 3,526 SNPs and is based on the MP01 mapping population, which counts 459 trees from a cross between the resistant 'TSH 1188' and the tolerant 'CCN 51' at the Mars Center for Cocoa Science in Barro Preto, Bahia, Brazil. Seven quantitative trait loci (QTL) that are associated with WBD were identified on five different chromosomes using a multi-trait QTL analysis for outbreeders. Phasing of the haplotypes at the major QTL region on chromosome IX on a diversity panel of genotypes clearly indicates that the major resistance locus comes from a well-known source of WBD resistance, the clone 'SCAVINA 6'. Various potential candidate genes identified within all QTL may be involved in different steps leading to disease resistance. Preliminary expression data indicate that at least three of these candidate genes may play a role during the first 12 h after infection, with clear differences between 'CCN 51' and 'TSH 1188'. We combined the information from a large mapping population with very distinct parents that segregate for WBD, a dense set of mapped markers, rigorous phenotyping capabilities and the availability of a sequenced genome to identify several genomic regions that are involved in WBD resistance. We also identified a novel source of resistance that most likely comes from the 'CCN 51' parent. Thanks to the large population size of the MP01 population, we were able to pick up QTL and markers with relatively small effects that can contribute to the creation and selection of more tolerant/resistant plant material.

  17. QTLs for straw quality characteristics identified in recombinant inbred lines of a Hordeum vulgare x H spontaneum cross in a Mediterranean environment

    DEFF Research Database (Denmark)

    Grando, S.; Baum, M.; Ceccarelli, S.

    2005-01-01

    , difficult to improve with empirical breeding. The objective of this study was to identify molecular markers to facilitate the improvement of straw quality in barley. For this purpose, we have used the genetic linkage map that was already developed for recombinant inbred lines (RILs) of the cross between...... a Hordeum vulgare cultivar (`Arta') and a H. spontaneum line (H. spontaneum 41-1), covering a total of 890 cM. Straw parameters from RILs grown at Tel Hadya and Breda (ICARDA's research stations) in 2 years (1996/1997 and 1997/1998) were analyzed by NIRS for predicted nutritional characteristics including...... neutral detergent fiber, acid detergent fiber, lignin, digestible organic matter in dry matter, voluntary intake, crude protein, and straw morphology (the percentage of blades, sheaths, and stems). Localization of QTLs was performed using Windows QTL Cartographer, version 2.0. Seventy-three QTLs were...

  18. Using Concept Mapping to Develop a Strategy for Self-Management Support for Underserved Populations Living With Chronic Conditions, British Columbia, August 2013-June 2014.

    Science.gov (United States)

    Mills, Susan L; Bergeron, Kim; Pérez, Guillermina

    2015-10-08

    Self-management support (SMS) is an essential component of public health approaches to chronic conditions. Given increasing concerns about health equity, the needs of diverse populations must be considered. This study examined potential solutions for addressing the gaps in self-management support initiatives for underserved populations. Stakeholders representing government, nongovernment organizations, Aboriginal communities, health authorities, medical practices, and research institutions generated, sorted, and rated ideas on what could be done to improve self-management support for underserved populations. Concept mapping was used to facilitate the collection and organization of the data and to generate conceptual maps. Participants generated 92 ideas that were sorted into 11 clusters (foster partnerships, promote integrated community care, enhance health care provider training, shift government policy, support community development, increase community education, enable client engagement, incorporate client support systems, recognize client capacity, tailor self-management support programs, and develop client skills, training, and tools) and grouped into system, community, and individual levels within a partnership framework. The strategy can stimulate public health dialogue and be a roadmap for developing SMS initiatives. It has the potential to address SMS and chronic condition inequities in underserved populations in several ways: 1) by targeting populations that have greater inequities, 2) by advocating for shifts in government policies that create and perpetuate inequities, 3) by promoting partnerships that may increase the number of SMS initiatives for underserved groups, and 4) by promoting training and engagement that increase the relevance, uptake, and overall effectiveness of SMS.

  19. Quantitative trait loci mapping of calving and conformation traits on Bos taurus autosome 18 in the German Holstein population.

    Science.gov (United States)

    Brand, B; Baes, C; Mayer, M; Reinsch, N; Seidenspinner, T; Thaller, G; Kühn, Ch

    2010-03-01

    Linkage, linkage disequilibrium, and combined linkage and linkage disequilibrium analyses were performed to map quantitative trait loci (QTL) affecting calving and conformation traits on Bos taurus autosome 18 (BTA18) in the German Holstein population. Six paternal half-sib families consisting of a total of 1,054 animals were genotyped on 28 genetic markers in the telomeric region on BTA18 spanning approximately 30 Mb. Calving traits, body type traits, and udder type traits were investigated. Using univariately estimated breeding values, maternal and direct effects on calving ease and stillbirth were analyzed separately for first- and further-parity calvings. The QTL initially identified by separate linkage and linkage disequilibrium analyses could be confirmed by a combined linkage and linkage disequilibrium analysis for udder composite index, udder depth, fore udder attachment, front teat placement, body depth, rump angle, and direct effects on calving ease and stillbirth. Concurrence of QTL peaks and a similar shape of restricted log-likelihood ratio profiles were observed between udder type traits and for body depth and calving traits, respectively. Association analyses were performed for markers flanking the most likely QTL positions by applying a mixed model including a fixed allele effect of the maternally inherited allele and a random polygenic effect. Results indicated that microsatellite marker DIK4234 (located at 53.3 Mb) is associated with maternal effects on stillbirth, direct effects on calving ease, and body depth. A comparison of effects for maternally inherited DIK4234 alleles indicated a favorable, positive correlation of maternal and direct effects on calving. Additionally, the association of maternally inherited DIK4234 marker alleles with body depth implied that conformation traits might provide the functional background of the QTL for calving traits. For udder type traits, the strong coincidence of QTL peaks and the position of the QTL in a

  20. Population.

    Science.gov (United States)

    International Planned Parenthood Federation, London (England).

    In an effort to help meet the growing interest and concern about the problems created by the rapid growth of population, The International Planned Parenthood Federation has prepared this booklet with the aim of assisting the study of the history and future trends of population growth and its impact on individual and family welfare, national,…

  1. Study of the epidemiology of type 2 diabetes in inbred populations in Western Algeria

    International Nuclear Information System (INIS)

    Sahi, M. D; Benmansour, A.; Aouar, A.; Karam, N.

    2012-01-01

    The study, conducted in western Algeria on a sample of 1561 individuals, 830 with type 2 diabetes and 731 witnesses, has established a profile of high-risk individuals of type 2 diabetes. The characters studied related significantly to diabetes for the 2 sexes, consanguinity (OR =2.3, 95% CI = 2.36 - 4.34,p< 0.01), the heredity factor (OR = 2.02, 95% CI = 1.41 - 2.88,p< 0.01), the geographic gradient (p< 0.01), the slice age which is between 40 and 54 years (OR = 2.51, 95% CI = 1.48-4.25,p< 0.01)and in 54 years and over (OR = 6.57, 95% CI = 3.92-11.0,p< 0.01), the overweight (OR = 1.57, 95% CI = 1.04-2.36, p = 0.031) and obesity (OR = 1.85, 95% CI = 1.15-2.98, p = 0.011) marital status (OR = 3.68, 95% CI = 1.60-8.45,p < 0.01) and type of housing (individual or collective house, OR = 0.36, 95%, CI = 0.20-0.63, p< 0.01). (author)

  2. Quantitative trait local analysis of growth-related traits in a new Arabidopsis recombinant inbred population

    NARCIS (Netherlands)

    El-Lithy, M.E.M.; Clerkx, E.J.M.; Ruijs, G.J.; Koornneef, M.; Vreugdenhil, D.

    2004-01-01

    Arabidopsis natural variation was used to analyze the genetics of plant growth rate. Screening of 22 accessions revealed a large variation for seed weight, plant dry weight and relative growth rate but not for water content. A positive correlation was observed between seed weight and plant area 10 d

  3. Digital phenotyping for quantification of genetic diversity in inbred guava (Psidium guajava) families.

    Science.gov (United States)

    Krause, W; Viana, A P; Cavalcante, N R; Ambrósio, M; Santos, E A; Vieira, H D

    2017-03-22

    Digital image analysis of seeds has been used for the identification of cultivars, determination of seed color and mechanical damage, and classification of different seed sizes. The aim of the present study was to evaluate the efficiency of digital image analysis of seeds for the quantification of genetic diversity among genotypes of inbred guava (Psidium guajava L.) families. The SAS Mini equipment, which consists of a capture module and a software program for analysis, was employed for the capture and analysis of the seed images. Different genetic diversity quantification strategies were tested using the Ward-Modified Location Model method. The set of variables related to geometry of the seeds was the largest contributor to divergence among the guava genotypes. The use of seed descriptors obtained by digital image analysis via the SAS system was efficient at quantifying the genetic diversity among genotypes of inbred guava families associated with the use of the Ward-Modified Location Model method.

  4. QTL mapping of resistance to gray leaf spot in maize.

    Science.gov (United States)

    Zhang, Yan; Xu, Ling; Fan, Xingming; Tan, Jing; Chen, Wei; Xu, Mingliang

    2012-12-01

    Gray leaf spot (GLS), caused by the causal fungal pathogen Cercospora zeae-maydis, is one of the most serious foliar diseases of maize worldwide. In the current study, a highly resistant inbred line Y32 and a susceptible line Q11 were used to produce segregating populations for both genetic analysis and QTL mapping. The broad-sense heritability (H (2)) for GLS resistance was estimated to be as high as 0.85, indicating that genetic factors played key roles in phenotypic variation. In initial QTL analysis, four QTL, located on chromosomes 1, 2, 5, and 8, were detected to confer GLS resistance. Each QTL could explain 2.53-23.90 % of the total phenotypic variation, predominantly due to additive genetic effects. Two major QTL, qRgls1 and qRgls2 on chromosomes 8 and 5, were consistently detected across different locations and replicates. Compared to the previous results, qRgls2 is located in a 'hotspot' for GLS resistance; while, qRgls1 does not overlap with any other known resistance QTL. Furthermore, the major QTL-qRgls1 was fine-mapped into an interval of 1.4 Mb, flanked by the markers GZ204 and IDP5. The QTL-qRgls1 could enhance the resistance percentages by 19.70-61.28 %, suggesting its usefulness to improve maize resistance to GLS.

  5. Single Nucleotide Polymorphism Identification, Characterization, and Linkage Mapping in Quinoa

    Directory of Open Access Journals (Sweden)

    P. J. Maughan

    2012-11-01

    Full Text Available Quinoa ( Willd. is an important seed crop throughout the Andean region of South America. It is important as a regional food security crop for millions of impoverished rural inhabitants of the Andean Altiplano (high plains. Efforts to improve the crop have led to an increased focus on genetic research. We report the identification of 14,178 putative single nucleotide polymorphisms (SNPs using a genomic reduction protocol as well as the development of 511 functional SNP assays. The SNP assays are based on KASPar genotyping chemistry and were detected using the Fluidigm dynamic array platform. A diversity screen of 113 quinoa accessions showed that the minor allele frequency (MAF of the SNPs ranged from 0.02 to 0.50, with an average MAF of 0.28. Structure analysis of the quinoa diversity panel uncovered the two major subgroups corresponding to the Andean and coastal quinoa ecotypes. Linkage mapping of the SNPs in two recombinant inbred line populations produced an integrated linkage map consisting of 29 linkage groups with 20 large linkage groups, spanning 1404 cM with a marker density of 3.1 cM per SNP marker. The SNPs identified here represent important genomic tools needed in emerging plant breeding programs for advanced genetic analysis of agronomic traits in quinoa.

  6. Linkage Map Construction and Quantitative Trait Locus Analysis of Agronomic and Fiber Quality Traits in Cotton

    Directory of Open Access Journals (Sweden)

    Michael A. Gore

    2014-03-01

    Full Text Available The superior fiber properties of L. serve as a source of novel variation for improving fiber quality in Upland cotton ( L., but introgression from has been largely unsuccessful due to hybrid breakdown and a lack of genetic and genomic resources. In an effort to overcome these limitations, we constructed a linkage map and conducted a quantitative trait locus (QTL analysis of 10 agronomic and fiber quality traits in a recombinant inbred mapping population derived from a cross between TM-1, an Upland cotton line, and NM24016, an elite line with stabilized introgression from . The linkage map consisted of 429 simple-sequence repeat (SSR and 412 genotyping-by-sequencing (GBS-based single-nucleotide polymorphism (SNP marker loci that covered half of the tetraploid cotton genome. Notably, the 841 marker loci were unevenly distributed among the 26 chromosomes of tetraploid cotton. The 10 traits evaluated on the TM-1 × NM24016 population in a multienvironment trial were highly heritable, and most of the fiber traits showed considerable transgressive variation. Through the QTL analysis, we identified a total of 28 QTLs associated with the 10 traits. Our study provides a novel resource that can be used by breeders and geneticists for the genetic improvement of agronomic and fiber quality traits in Upland cotton.

  7. Multi-trait association mapping in sugar beet (Beta vulgaris L.).

    Science.gov (United States)

    Stich, Benjamin; Piepho, Hans-Peter; Schulz, Britta; Melchinger, Albrecht E

    2008-10-01

    Association mapping promises to overcome the limitations of linkage mapping methods. The main objective of this study was to examine the applicability of multivariate association mapping with an empirical data set of sugar beet. A total of 111 diploid sugar beet inbreds was selected from the seed parent heterotic pool to represent a broad diversity with respect to sugar content (SC). The inbreds were genotyped with 26 simple sequence repeat markers chosen according to their map positions in proximity to previously identified quantitative trait loci for SC. For SC and beet yield (BY), the genotypic variances were highly significant (P sugar beet breeding context for detection of marker-phenotype associations. Furthermore, based on our results multivariate association mapping can be recommended as a promising tool to discriminate with a high mapping resolution between pleiotropy and linkage as reasons for co-localization of marker-phenotype associations for different traits.

  8. Seedling growth of maize (Zea mays L.) inbred lines affected by seed treatment with pesticides

    OpenAIRE

    Tamindžić, Gordana D.; Nikolić, Zorica T.; Savić, Jasna Ž.; Milošević, Dragana N.; Petrović, Gordana R.; Ivanović, Dragana D.; Ignjatov, Maja V.

    2016-01-01

    Seed treatment is a common way of fungicide and insecticide use nowadays, since this way of pesticide application can provide the best protection in the vicinity of the future plant. The aim of research was to evaluate the effects of different seed treatments on germination and seedling growth in three maize inbred lines. The research included the seed treatment with several combinations of a fungicide Maxim XL 035-FS (a.i. metalaxil-M + fludioxonil) and ne...

  9. Genetic repairing through storage of gamma irradiated seeds in inbred maize (Zea mays L.)

    OpenAIRE

    KUMAR, Girjesh; RAI, Prashant KUMAR

    2009-01-01

    Gamma irradiation can induce beneficial as well as deleterious impacts on chromosome behavior in crop plants. The cytogenetic changes occurring due to the storage of inbred seeds after gamma irradiation in the somatic and gametic cells of Zea mays L. were investigated in this study. A wide spectrum of chromosomal anomalies was encountered in somatic and gametic cells of maize that are gamma irradiated, stored (aged), and treated with a combination of both of these treatments. Gamma rays and a...

  10. Estimation of genetic variability level in inbred CF1 mouse lines ...

    Indian Academy of Sciences (India)

    Estimation of genetic variability level in inbred CF1 mouse lines selected for body weight. MAURICIO RENNY1, NORMA B. JULIO1, SANDRA F. BERNARDI2, CRISTINA N. GARDENAL1 and MARÍA INÉS OYARZABAL3∗. 1Cátedra de Genética de Poblaciones y Evolución, Facultad de Ciencias Exactas, Físicas y Naturales ...

  11. Agronomic and molecular evaluation of maize inbred lines for drought tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Mikić, S.; Zorić, M.; Stanisavljević, D.; Kondić-Špika, A.; Brbaklić, L.; Kobiljski, B.; Nastasić, A.; Mitrović, B.; Šurlan-Momirović, G.

    2016-07-01

    Drought is a severe threat to maize yield stability in Serbia and other temperate Southeast European countries occurring occasionally but with significant yield losses. The development of resilient genotypes that perform well under drought is one of the main focuses of maize breeding programmes. To test the tolerance of newly developed elite maize inbred lines to drought stress, field trials for grain yield performance and anthesis silk interval (ASI) were set in drought stressed environments in 2011 and 2012. Inbred lines performing well under drought, clustered into a group with short ASI and a smaller group with long ASI, were considered as a potential source for tolerance. The former contained inbreds from different heterotic groups and with a proportion of local germplasm. The latter consisted of genotypes with mixed exotic and Lancaster germplasm, which performed better in more drought-affected environments. Three inbreds were selected for their potential drought tolerance, showing an above-average yield and small ASI in all environments. Association analysis indicated significant correlations between ASI and grain yield and three microsatellites (bnlg1525, bnlg238 and umc1025). Eight alleles were selected for their favourable concurrent effect on yield increase and ASI decrease. The proportion of phenotypic variation explained by the markers varied across environments from 5.7% to 22.4% and from 4.6% to 8.1% for ASI and yield, respectively. The alleles with strongest effect on performance of particular genotypes and their interactions in specific environments were identified by the mean of partial least square interactions analysis indicating potential suitability of the makers for tolerant genotype selection.

  12. Fibre type composition of soleus and extensor digitorum longus muscles in normal female inbred Lewis rats

    Czech Academy of Sciences Publication Activity Database

    Soukup, Tomáš; Zachařová, Gisela; Smerdu, V.

    2002-01-01

    Roč. 104, č. 4 (2002), s. 399-405 ISSN 0065-1281 R&D Projects: GA ČR GA304/00/1653 Grant - others:CZ - SI Czech-Slovenian Intergovernmental S&T Co-operation(XC) - Institutional research plan: CEZ:AV0Z5011922 Keywords : inbred Lewis rats * skeletal muscles * soleus and EDL muscles Subject RIV: FH - Neurology Impact factor: 0.867, year: 2002

  13. Genetic determination of the biological radiation response in inbred mice lines

    International Nuclear Information System (INIS)

    Gomolka, M.; Hornhardt, S.; Jung, T.

    2000-01-01

    Variation in radiation sensitivity and radiation resistance is influenced by the genetic constitution of an individual. Loss of function of genes involved in DNA repair, cell cycle or controlled cell death can have serious consequences on individual radiation sensitivity. For example, individuals suffering on the clinical syndrome of Ataxia telangiectasia exhibit radiation sensitivity in the order of 2-3 magnitudes higher than other cancer patients. For radiation protection it is important to clarify the role of genetic predisposition for radiation sensitivity in clinical healthy people. Therefore, data were collected from the literature describing the genetic variation (heritability) of radiation sensitivity in the mouse model. A heritability of 30-50% was calculated for 27 inbred mice lines by Roderick (1963) based on days of survival after a daily dose of 1 Gy γ-irradiation. The following inbred lines were described in the literature as radiation sensitive (phenotypical markers were e.g., time of survival, mortality, reduction in fertility post exposure): SWR, RIII, NC, K, HLG, DBA, CBA, BALB/c, A, AKR. Radiation resistance was demonstrated in SJL, SEC, RF, MA, C58, C57BR, BDP and 129. Parameter of longevity, some physiological, biochemical and immunological parameters as given in the data bank of the Jackson Laboratory, U.S.A., were compared between radiation sensitive and radiation resistant inbred strains. No correlation was seen for the most of the parameters except for the development of breast cancer. In 6 out of 10 radiosensitive inbred strains breast cancer is described while only 1 of 8 strains exhibits breast cancer. The higher heritability of 30-50% in spite of a very complex phenotype like survival and the correlation between radiosensitivity and tumour incidence show that individual genetic susceptibility is important on the biological radiation reaction. (orig.) [de

  14. Genotypic effects on boron concentrations and response on boron fertilization in maize inbred lines

    OpenAIRE

    Andrić Luka; Kovačević Vlado; Kadar Imre; Jambrović Antun; Plavšić Hrvoje; Šimić Domagoj

    2016-01-01

    Boron (B) deficiency in maize can result in barren cobs attributed to silks being nonreceptive which is particularly important for the female parent in seed production. The objectives of this study were 1) to investigate genotypic differences among nine female inbred lines used in seed production for B concentration in ear-leaf and grain, as well as for grain yield and moisture in a three-year experiment (2006-2008) and 2) to determine response and relation...

  15. Highly efficient generation of GGTA1 biallelic knockout inbred mini-pigs with TALENs.

    Directory of Open Access Journals (Sweden)

    Jige Xin

    Full Text Available Inbred mini-pigs are ideal organ donors for future human xenotransplantations because of their clear genetic background, high homozygosity, and high inbreeding endurance. In this study, we chose fibroblast cells from a highly inbred pig line called Banna mini-pig inbred line (BMI as donor nuclei for nuclear transfer, combining with transcription activator-like effector nucleases (TALENs and successfully generated α-1,3-galactosyltransferase (GGTA1 gene biallelic knockout (KO pigs. To validate the efficiency of TALEN vectors, in vitro-transcribed TALEN mRNAs were microinjected into one-cell stage parthenogenetically activated porcine embryos. The efficiency of indel mutations at the GGTA1-targeting loci was as high as 73.1% (19/26 among the parthenogenetic blastocysts. TALENs were co-transfected into porcine fetal fibroblasts of BMI with a plasmid containing neomycin gene. The targeting efficiency reached 89.5% (187/209 among the survived cell clones after a 10 d selection. More remarkably 27.8% (58/209 of colonies were biallelic KO. Five fibroblast cell lines with biallelic KO were chosen as nuclear donors for somatic cell nuclear transfer (SCNT. Three miniature piglets with biallelic mutations of the GGTA1 gene were achieved. Gal epitopes on the surface of cells from all the three biallelic KO piglets were completely absent. The fibroblasts from the GGTA1 null piglets were more resistant to lysis by pooled complement-preserved normal human serum than those from wild-type pigs. These results indicate that a combination of TALENs technology with SCNT can generate biallelic KO pigs directly with high efficiency. The GGTA1 null piglets with inbred features created in this study can provide a new organ source for xenotransplantation research.

  16. Agronomic and molecular evaluation of maize inbred lines for drought tolerance

    International Nuclear Information System (INIS)

    Mikić, S.; Zorić, M.; Stanisavljević, D.; Kondić-Špika, A.; Brbaklić, L.; Kobiljski, B.; Nastasić, A.; Mitrović, B.; Šurlan-Momirović, G.

    2016-01-01

    Drought is a severe threat to maize yield stability in Serbia and other temperate Southeast European countries occurring occasionally but with significant yield losses. The development of resilient genotypes that perform well under drought is one of the main focuses of maize breeding programmes. To test the tolerance of newly developed elite maize inbred lines to drought stress, field trials for grain yield performance and anthesis silk interval (ASI) were set in drought stressed environments in 2011 and 2012. Inbred lines performing well under drought, clustered into a group with short ASI and a smaller group with long ASI, were considered as a potential source for tolerance. The former contained inbreds from different heterotic groups and with a proportion of local germplasm. The latter consisted of genotypes with mixed exotic and Lancaster germplasm, which performed better in more drought-affected environments. Three inbreds were selected for their potential drought tolerance, showing an above-average yield and small ASI in all environments. Association analysis indicated significant correlations between ASI and grain yield and three microsatellites (bnlg1525, bnlg238 and umc1025). Eight alleles were selected for their favourable concurrent effect on yield increase and ASI decrease. The proportion of phenotypic variation explained by the markers varied across environments from 5.7% to 22.4% and from 4.6% to 8.1% for ASI and yield, respectively. The alleles with strongest effect on performance of particular genotypes and their interactions in specific environments were identified by the mean of partial least square interactions analysis indicating potential suitability of the makers for tolerant genotype selection.

  17. High-resolution linkage map and chromosome-scale genome assembly for cassava (Manihot esculenta Crantz) from 10 populations.

    Science.gov (United States)

    2014-12-11

    Cassava (Manihot esculenta Crantz) is a major staple crop in Africa, Asia, and South America, and its starchy roots provide nourishment for 800 million people worldwide. Although native to South America, cassava was brought to Africa 400-500 years ago and is now widely cultivated across sub-Saharan Africa, but it is subject to biotic and abiotic stresses. To assist in the rapid identification of markers for pathogen resistance and crop traits, and to accelerate breeding programs, we generated a framework map for M. esculenta Crantz from reduced representation sequencing [genotyping-by-sequencing (GBS)]. The composite 2412-cM map integrates 10 biparental maps (comprising 3480 meioses) and organizes 22,403 genetic markers on 18 chromosomes, in agreement with the observed karyotype. We used the map to anchor 71.9% of the draft genome assembly and 90.7% of the predicted protein-coding genes. The chromosome-anchored genome sequence will be useful for breeding improvement by assisting in the rapid identification of markers linked to important traits, and in providing a framework for genomic selection-enhanced breeding of this important crop. Copyright © 2015 International Cassava Genetic Map Consortium (ICGMC).

  18. Development of CACTA transposon derived SCAR markers and their use in population structure analysis in Zea mays.

    Science.gov (United States)

    Roy, Neha Samir; Park, Kyong-Cheul; Lee, Sung-Il; Im, Min-Ji; Ramekar, Rahul Vasudeo; Kim, Nam-Soo

    2018-02-01

    Molecular marker technologies have proven to be an important breakthrough for genetic studies, construction of linkage maps and population genetics analysis. Transposable elements (TEs) constitute major fractions of repetitive sequences in plants and offer a wide range of possible areas to be explored as molecular markers. Sequence characterized amplified region (SCAR) marker development provides us with a simple and time saving alternative approach for marker development. We employed the CACTA-TD to develop SCARs and then integrated them into linkage map and used them for population structure and genetic diversity analysis of corn inbred population. A total of 108 dominant SCAR markers were designed out of which, 32 were successfully integrated in to the linkage map of maize RIL population and the remaining were added to a physical map for references to check the distribution throughout all chromosomes. Moreover, 76 polymorphic SCARs were used for diversity analysis of corn accessions being used in Korean corn breeding program. The overall average polymorphic information content (PIC) was 0.34, expected heterozygosity was 0.324 and Shannon's information index was 0.491 with a percentage of polymorphism of 98.67%. Further analysis by associating with desirable traits may also provide some accurate trait specific tagged SCAR markers. TE linked SCARs can provide an added level of polymorphism as well as improved discriminating ability and therefore can be useful in further breeding programs to develop high yielding germplasm.

  19. Low Elevation Coastal Zone (LECZ) Urban-Rural Population Estimates, Global Rural-Urban Mapping Project (GRUMP), Alpha Version

    Data.gov (United States)

    National Aeronautics and Space Administration — The Low Elevation Coastal Zone (LECZ) Urban-Rural Population Estimates consists of country-level estimates of urban, rural and total population and land area...

  20. Popping volume and grain yield in diallel set of popcorn inbred lines

    Directory of Open Access Journals (Sweden)

    Pajić Zorica

    2008-01-01

    Full Text Available Popping volume and yield are traits caused by several heredity factors. It is difficult to obtain superior genotypes for both traits but it is possible to develop genotypes with good popping volume and satisfactory yield. The hybrid ZPPL2 x ZPPL5 was superior in yield, heterosis and SCA for both yield and popping volume. As inbred ZPPL4 in all combinations has a good value for popping volume could be concluded that this inbred may be used as parent in further crosses. Analysis of variance of the combining ability indicating significant SCA effect for grain yield, and significant both GCA and SCA effects for popping volume. Therefore it can be stated that yield is influenced by non-additive and popping volume by both additive and non- additive gene effects. Analysis of variance of genetic components for popping volume indicates that the additive as well as dominant components significantly affected the inheritance of this trait in popcorn. The objective of this study was to evaluate heteorsis and combing ability for grain yield and popping volume in dialalel set of six maize inbred lines.

  1. Mapping of QTL for tiller number at different stages of growth in wheat using double haploid and immortalized F2 populations.

    Science.gov (United States)

    Li, Zhuokun; Peng, Tao; Xie, Quangang; Han, Shuxiao; Tian, Jichun

    2010-12-01

    Effective tiller number is one of the most important traits for wheat (Triticum aestivum L.) yield, but the inheritance of tillering is poorly understood. A set of 168 doubled haploid (DH) lines derivatives of a cross between two winter wheat cultivars (Huapei 3 and Yumai 57), and an immortalized F(2) (IF(2)) population generated by randomly permutated intermating of these DHs were investigated, and QTLs of tillering related to the maximum tillering of pre-winter (MTW), maximum tillering in spring (MTS), and effective tillering in harvest (ETH) were mapped. Phenotypic data were collected for the two populations from two different environments. Using inclusive composite interval mapping (ICIM), a total of 9 and 18 significant QTL were detected across environments for tillering in the DH and IF(2) populations, respectively. Four QTLs were common between two populations. A major QTL located on the 5D chromosome with the allele originating from Yumai 57 was detected and increased 1.92 and 3.55 tillers in MTW and MTS, respectively. QTLs (QMts6D, QEth6D) having a neighbouring marker interval at Xswes679.1 and Xcfa2129 on chromosome 6D was detected in MTS and ETH. These results provide a better understanding of the genetic factors for selectively expressing the control of tiller number in different growth stages and facilitate marker-assisted selection strategy in breeding.

  2. Linkage Maps of a Mediterranean × Continental Tall Fescue Population and their Comparative Analysis with Other Poaceae Species

    Directory of Open Access Journals (Sweden)

    Ryan Dierking

    2015-03-01

    Full Text Available Temperate grasses belonging to the complex are important throughout the world in pasture and grassland agriculture. Tall fescue ( Schreb. is the predominant species in the United States, covering approximately 15 million ha. Tall fescue has distinctive morphotypes, two of which are Continental (summer active and Mediterranean (summer semidormant. This is the first report of a linkage map created for Mediterranean tall fescue, while updating the Continental map with additional simple sequence repeat and sequence-tagged site markers. Additionally, this is the first time that diversity arrays technology (DArT markers were used in the construction of a tall fescue map. The male parent (Continental, R43-64, map consisted of 594 markers arranged in 22 linkage groups (LGs and covered a total of 1577 cM. The female parent (Mediterranean, 103-2, map was shorter (1258 cM and consisted of only 208 markers arranged in 29 LGs. Marker densities for R43-64 and 103-2 were 2.65 and 6.08 cM per marker, respectively. When compared with the other Poaceae species, meadow fescue ( Huds., annual ryegrass ( Lam., perennial ryegrass ( L., (L. Beauv., and barley ( L., a total of 171 and 98 orthologous or homologous sequences, identified by DArT analysis, were identified in R43-64 and 103-2, respectively. By using genomic in situ hybridization, we aimed to identify potential progenitors of both morphotypes. However, no clear conclusion on genomic constitution was reached. These maps will aid in the search for quantitative trait loci of various traits as well as help define and distinguish genetic differences between the two morphotypes.

  3. Characterization of microbial population of breba and main crops (Ficus carica) during cold storage: Influence of passive modified atmospheres (MAP) and antimicrobial extract application.

    Science.gov (United States)

    Villalobos, María Del Carmen; Serradilla, Manuel Joaquín; Martín, Alberto; Hernández-León, Alejandro; Ruíz-Moyano, Santiago; Córdoba, María de Guía

    2017-05-01

    The purpose of this work was to study the changes of bacterial and fungal population of breba fruits such as 'Banane' and 'San Antonio' as well as 'Cuello Dama Negro', 'Cuello Dama Blanco' and 'San Antonio' fig cultivars stored in passive modified atmospheres (MAP) by the use of three different microperforated films (M10 with 16 holes; M30 with five holes and M50 with three holes). Moreover the effects of the application of aqueous soy polyphenolic antimicrobial extract (APE), alone or combined with MAP, were also studied for 'Cuello Dama Negro' and 'Cuello Dama Blanco' fig cultivars. Bacteria and fungi isolates were identified by PCR-RFLP of 16S rRNA and ITS regions, respectively, and subsequently sequence of the different patterns obtained. The results indicated that Pseudomonas gessardii, Pantoea agglomerans and Enterobacter asburiae were the main species of bacteria found in all the treatments studied. The fungal species identified were Aureobasidium pulullans, Cladosporium cladosporioides and Alternaria alternata, which were found in a lower percentage in fruit stored in MAP and fruits treated with antimicrobial extracts, as this treatments allowed to reduce the microbial growth of moulds and yeasts. Thus, the application of treatments such as M30, M50 or the combination of MAP with antimicrobial extract was highly effective to control fruit spoilage in fig and breba crops. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Evidence should trump intuition by preferring inbred strains to outbred stocks in preclinical research.

    Science.gov (United States)

    Festing, Michael F W

    2014-01-01

    Inbred strains of mice such as C57BL and BALB/c are more widely used in published work than outbred stocks of mice such as ICR and CD-1. In contrast, outbred stocks of rats such as Wistar and Sprague-Dawley are more widely used than inbred strains such as F344 and LEW. The properties of inbred and outbred mice and rats are briefly reviewed, and it is concluded that, with some exceptions, there is a strong case for using inbred strains in most controlled experiments. This is because they are usually more uniform, so that fewer animals are usually needed to detect a specified response and they are more repeatable, because they are genetically defined (i.e., the strain can be identified using genetic markers) and less liable to genetic change. Yet many scientists continue to use outbred animals. In Daniel Kahneman's book "Thinking Fast and Slow" he explains that we can answer questions in 2 ways: "fast" by intuition or "slow" by analytical reasoning. The former method is instantaneous, requires no thought but is not evidence based. Analytical reasoning is evidence based but requires hard work, which we all avoid. He has found that "… when faced with a difficult question, we often answer an easier one instead, usually without noticing the substitution." The target question of whether to choose outbred or inbred strains in controlled experiments is a difficult one requiring knowledge of the characteristics of these strains and the principles of experimental design. A substitute question, "are humans and outbred stocks both genetically heterogeneous," is easily answered in the affirmative. It is likely that many scientists are intuitively answering the substitute question and are assuming that they have answered the target question. If so they may be using the wrong animals in their research. Nor is the fact that humans and outbred stocks are alike in being genetically heterogeneous a reason for using them. The whole concept of a "model" is that it is similar to the

  5. Detailed mapping of a resistance locus against Fusarium wilt in cultivated eggplant (Solanum melongena).

    Science.gov (United States)

    Miyatake, Koji; Saito, Takeo; Negoro, Satomi; Yamaguchi, Hirotaka; Nunome, Tsukasa; Ohyama, Akio; Fukuoka, Hiroyuki

    2016-02-01

    This is the first report on genetic mapping of a resistance locus against Fusarium wilt caused by the plant pathogen Fusarium oxysporum f. sp. melongenae in cultivated eggplant. Fusarium wilt, caused by the plant pathogen Fusarium oxysporum f. sp. melongenae, is a major soil-borne disease threatening stable production in eggplant (Solanum melongena). Although three eggplant germplasms, LS1934, LS174, and LS2436, are known to be highly resistant to the pathogen, their resistance loci have not been mapped. In this study, we performed quantitative trait locus analyses in F2:3 populations and detected a resistance locus, FM1, at the end of chromosome 2, with two alleles, Fm1(L) and Fm1(E), in the F2 populations LWF2 [LS1934 × WCGR112-8 (susceptible)] and EWF2 [EPL-1 (derived from LS174) × WCGR112-8], respectively. The percentage of phenotypic variance explained by Fm1(L) derived from LS1934 was 75.0% [Logarithm of the odds (LOD) = 29.3], and that explained by Fm1(E) derived from EPL-1 was 92.2% (LOD = 65.8). Using backcrossed inbred lines, we mapped FM1 between two simple sequence repeat markers located ~4.881 cM apart from each other. Comparing the location of the above locus to those of previously reported ones, the resistance locus Rfo-sa1 from an eggplant ally (Solanum aethiopicum gr. Gilo) was mapped very close to FM1, whereas another resistance locus, from LS2436, was mapped to the middle of chromosome 4. This is the first report of mapping of a Fusarium resistance locus in cultivated eggplant. The availability of resistance-linked markers will enable the application of marker-assisted selection to overcome problems posed by self-incompatibility and introduction of negative traits because of linkage drag, and will lead to clear understanding of genetic mechanism of Fusarium resistance.

  6. Mapping QTL Contributing to Variation in Posterior Lobe Morphology between Strains of Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Jennifer L Hackett

    Full Text Available Closely-related, and otherwise morphologically similar insect species frequently show striking divergence in the shape and/or size of male genital structures, a phenomenon thought to be driven by sexual selection. Comparative interspecific studies can help elucidate the evolutionary forces acting on genital structures to drive this rapid differentiation. However, genetic dissection of sexual trait divergence between species is frequently hampered by the difficulty generating interspecific recombinants. Intraspecific variation can be leveraged to investigate the genetics of rapidly-evolving sexual traits, and here we carry out a genetic analysis of variation in the posterior lobe within D. melanogaster. The lobe is a male-specific process emerging from the genital arch of D. melanogaster and three closely-related species, is essential for copulation, and shows radical divergence in form across species. There is also abundant variation within species in the shape and size of the lobe, and while this variation is considerably more subtle than that seen among species, it nonetheless provides the raw material for QTL mapping. We created an advanced intercross population from a pair of phenotypically-different inbred strains, and after phenotyping and genotyping-by-sequencing the recombinants, mapped several QTL contributing to various measures of lobe morphology. The additional generations of crossing over in our mapping population led to QTL intervals that are smaller than is typical for an F2 mapping design. The intervals we map overlap with a pair of lobe QTL we previously identified in an independent mapping cross, potentially suggesting a level of shared genetic control of trait variation. Our QTL additionally implicate a suite of genes that have been shown to contribute to the development of the posterior lobe. These loci are strong candidates to harbor naturally-segregating sites contributing to phenotypic variation within D. melanogaster, and

  7. The SAURON project - XI. Stellar populations from absorption-line strength maps of 24 early-type spirals

    NARCIS (Netherlands)

    Peletier, Reynier F.; Falcon-Barroso, Jesus; Bacon, Roland; Cappellari, Michele; Davies, Roger L.; de Zeeuw, P. T.; Emsellem, Eric; Ganda, Katia; Krajnovic, Davor; Kuntschner, Harald; McDermid, Richard M.; Sarzi, Marc; van de Ven, Glenn

    2007-01-01

    We present absorption-line strength maps of a sample of 24 representative early-type spiral galaxies, mostly of type Sa, obtained as part of the SAURON (Spectrographic Areal Unit for Research on Optical Nebulae) survey of nearby galaxies using our custom-built integral-field spectrograph. Using

  8. Novel fluorescent sequence-related amplified polymorphism(FSRAP markers for the construction of a genetic linkage map of wheat(Triticum aestivum L.

    Directory of Open Access Journals (Sweden)

    Zhao Lingbo

    2017-01-01

    Full Text Available Novel fluorescent sequence-related amplified polymorphism (FSRAP markers were developed based on the SRAP molecular marker. Then, the FSRAP markers were used to construct the genetic map of a wheat (Triticum aestivumL. recombinant inbred line population derived from a Chuanmai 42×Chuannong 16 cross. Reproducibility and polymorphism tests indicated that the FSRAP markers have repeatability and better reflect the polymorphism of wheat varieties compared with SRAP markers. A total of 430 polymorphic loci between Chuanmai 42 and Chuannong 16 were detected with 189 FSRAP primer combinations. A total of 281 FSARP markers and 39 SSR markers re classified into 20 linkage groups. The maps spanned a total length of 2499.3cM with an average distance of 7.81cM between markers. A total of 201 markers were mapped on the B genome and covered a distance of 1013cM. On the A genome, 84 markers were mapped and covered a distance of 849.6cM. On the D genome, however, only 35 markers were mapped and covered a distance of 636.7cM. No FSRAP markers were distributed on the 7D chromosome. The results of the present study revealed that the novel FSRAP markers can be used to generate dense, uniform genetic maps of wheat.

  9. QTLs and Potential Candidate Genes for Heat Stress Tolerance Identified from the Mapping Populations Specifically Segregating for Fv/Fm in Wheat

    Directory of Open Access Journals (Sweden)

    Dew Kumari Sharma

    2017-09-01

    Full Text Available Despite the fact that Fv/Fm (maximum quantum efficiency of photosystem II is the most widely used parameter for a rapid non-destructive measure of stress detection in plants, there are barely any studies on the genetic understanding of this trait under heat stress. Our aim was to identify quantitative trait locus (QTL and the potential candidate genes linked to Fv/Fm for improved photosynthesis under heat stress in wheat (Triticum aestivum L.. Three bi-parental F2 mapping populations were generated by crossing three heat tolerant male parents (origin: Afghanistan and Pakistan selected for high Fv/Fm with a common heat susceptible female parent (origin: Germany selected for lowest Fv/Fm out of a pool of 1274 wheat cultivars of diverse geographic origin. Parents together with 140 F2 individuals in each population were phenotyped by Fv/Fm under heat stress (40°C for 3 days around anthesis. The Fv/Fm decreased by 6.3% in the susceptible parent, 1–2.5% in the tolerant parents and intermediately 4–6% in the mapping populations indicating a clear segregation for the trait. The three populations were genotyped with 34,955 DArTseq and 27 simple sequence repeat markers, out of which ca. 1800 polymorphic markers mapped to 27 linkage groups covering all the 21 chromosomes with a total genome length of about 5000 cM. Inclusive composite interval mapping resulted in the identification of one significant and heat-stress driven QTL in each population on day 3 of the heat treatment, two of which were located on chromosome 3B and one on chromosome 1D. These QTLs explained about 13–35% of the phenotypic variation for Fv/Fm with an additive effect of 0.002–0.003 with the positive allele for Fv/Fm originating from the heat tolerant parents. Approximate physical localization of these three QTLs revealed the presence of 12 potential candidate genes having a direct role in photosynthesis and/or heat tolerance. Besides providing an insight into the genetic

  10. Identification of X-linked quantitative trait loci affecting cold tolerance in Drosophila melanogaster and fine mapping by selective sweep analysis.

    Science.gov (United States)

    Svetec, Nicolas; Werzner, Annegret; Wilches, Ricardo; Pavlidis, Pavlos; Alvarez-Castro, José M; Broman, Karl W; Metzler, Dirk; Stephan, Wolfgang

    2011-02-01

    Drosophila melanogaster is a cosmopolitan species that colonizes a great variety of environments. One trait that shows abundant evidence for naturally segregating genetic variance in different populations of D. melanogaster is cold tolerance. Previous work has found quantitative trait loci (QTL) exclusively on the second and the third chromosomes. To gain insight into the genetic architecture of cold tolerance on the X chromosome and to compare the results with our analyses of selective sweeps, a mapping population was derived from a cross between substitution lines that solely differed in the origin of their X chromosome: one originates from a European inbred line and the other one from an African inbred line. We found a total of six QTL for cold tolerance factors on the X chromosome of D. melanogaster. Although the composite interval mapping revealed slightly different QTL profiles between sexes, a coherent model suggests that most QTL overlapped between sexes, and each explained around 5-14% of the genetic variance (which may be slightly overestimated). The allelic effects were largely additive, but we also detected two significant interactions. Taken together, this provides evidence for multiple QTL that are spread along the entire X chromosome and whose effects range from low to intermediate. One detected transgressive QTL influences cold tolerance in different ways for the two sexes. While females benefit from the European allele increasing their cold tolerance, males tend to do better with the African allele. Finally, using selective sweep mapping, the candidate gene CG16700 for cold tolerance colocalizing with a QTL was identified. © 2010 Blackwell Publishing Ltd.

  11. Modelling risk of tick exposure in southern Scandinavia using machine learning techniques, satellite imagery, and human population density maps

    DEFF Research Database (Denmark)

    Kjær, Lene Jung; Korslund, L.; Kjelland, V.

    distribution (probability of presence) in southern Scandinavia. Together with the predicted distribution maps, we used human density maps to determine areas with high risk of exposure to ticks. For nymphs, the predicted distribution found corresponded well with known distributions of ticks in Scandinavia......Vector-borne diseases such as Lyme disease and tick-borne encephalitis have become more common in recent decades and present a real health problem in many parts of Europe. Risk assessment, control, and prevention of these diseases require a better understanding of vector abundance as well as risk...... factors determining human exposure to ticks. There is a great need for analyses and models that can predict how vectors and their associated diseases are distributed and how this relates to high risk areas for human exposure.As a part of the ScandTick Innovation project, we surveyed ticks at approximately...

  12. Data Preparation for West Nile Virus Agent-Based Modelling: Protocol for Processing Bird Population Estimates and Incorporating ArcMap in AnyLogic.

    Science.gov (United States)

    Nasrinpour, Hamid Reza; Reimer, Alexander A; Friesen, Marcia R; McLeod, Robert D

    2017-07-17

    West Nile Virus (WNV) was first isolated in 1937. Since the 1950s, many outbreaks have occurred in various countries. The first appearance of infected birds in Manitoba, Canada was in 2002. This paper describes the data preparation phase of setting up a geographic information system (GIS) simulation environment for WNV Agent-Based Modelling in Manitoba. The main technology used in this protocol is based on AnyLogic and ArcGIS software. A diverse variety of topics and techniques regarding the data collection phase are presented, as modelling WNV has many disparate attributes, including landscape and weather impacts on mosquito population dynamics and birds' roosting locations, population count, and movement patterns. Different maps were combined to create a grid land cover map of Manitoba, Canada in a shapefile format compatible with AnyLogic, in order to modulate mosquito parameters. A significant amount of data regarding 152 bird species, along with their population estimates and locations in Manitoba, were gathered and assembled. Municipality shapefile maps were converted to built-in AnyLogic GIS regions for better compatibility with census data and initial placement of human agents. Accessing shapefiles and their databases in AnyLogic are also discussed. AnyLogic simulation software in combination with Esri ArcGIS provides a powerful toolbox for developers and modellers to simulate almost any GIS-based environment or process. This research should be useful to others working on a variety of mosquito-borne diseases (eg, Zika, dengue, and chikungunya) by demonstrating the importance of data relating to Manitoba and/or introducing procedures to compile such data. ©Hamid Reza Nasrinpour, Alexander A Reimer, Marcia R Friesen, Robert D McLeod. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 17.07.2017.

  13. Fine-mapping of QTLs for individual and total isoflavone content in soybean (Glycine max L.) using a high-density genetic map.

    Science.gov (United States)

    Cai, Zhandong; Cheng, Yanbo; Ma, Zhuwen; Liu, Xinguo; Ma, Qibin; Xia, Qiuju; Zhang, Gengyun; Mu, Yinghui; Nian, Hai

    2018-03-01

    Fifteen stable QTLs were identified using a high-density soybean genetic map across multiple environments. One major QTL, qIF5-1, contributing to total isoflavone content explained phenotypic variance 49.38, 43.27, 46.59, 45.15 and 52.50%, respectively. Soybeans (Glycine max L.) are a major source of dietary isoflavones. To identify novel quantitative trait loci (QTL) underlying isoflavone content, and to improve the accuracy of marker-assisted breeding in soybean, a valuable mapping population comprised of 196 F 7:8-10 recombinant inbred lines (RILs, Huachun 2 × Wayao) was utilized to evaluate individual and total isoflavone content in plants grown in four different environments in Guangdong. A high-density genetic linkage map containing 3469 recombination bin markers based on 0.2 × restriction site-associated DNA tag sequencing (RAD-seq) technology was used to finely map QTLs for both individual and total isoflavone contents. Correlation analyses showed that total isoflavone content, and that of five individual isoflavone, was significantly correlated across the four environments. Based on the high-density genetic linkage map, a total of 15 stable quantitative trait loci (QTLs) associated with isoflavone content across multiple environments were mapped onto chromosomes 02, 05, 07, 09, 10, 11, 13, 16, 17, and 19. Further, one of them, qIF5-1, localized to chromosomes 05 (38,434,171-39,045,620 bp) contributed to almost all isoflavone components across all environments, and explained 6.37-59.95% of the phenotypic variance, especially explained 49.38, 43.27, 46.59, 45.15 and 52.50% for total isoflavone. The results obtained in the present study will pave the way for a better understanding of the genetics of isoflavone accumulation and reveals the scope available for improvement of isoflavone content through marker-assisted selection.

  14. Genomic selection and association mapping in rice (Oryza sativa: effect of trait genetic architecture, training population composition, marker number and statistical model on accuracy of rice genomic selection in elite, tropical rice breeding lines.

    Directory of Open Access Journals (Sweden)

    Jennifer Spindel

    2015-02-01

    Full Text Available Genomic Selection (GS is a new breeding method in which genome-wide markers are used to predict the breeding value of individuals in a breeding population. GS has been shown to improve breeding efficiency in dairy cattle and several crop plant species, and here we evaluate for the first time its efficacy for breeding inbred lines of rice. We performed a genome-wide association study (GWAS in conjunction with five-fold GS cross-validation on a population of 363 elite breeding lines from the International Rice Research Institute's (IRRI irrigated rice breeding program and herein report the GS results. The population was genotyped with 73,147 markers using genotyping-by-sequencing. The training population, statistical method used to build the GS model, number of markers, and trait were varied to determine their effect on prediction accuracy. For all three traits, genomic prediction models outperformed prediction based on pedigree records alone. Prediction accuracies ranged from 0.31 and 0.34 for grain yield and plant height to 0.63 for flowering time. Analyses using subsets of the full marker set suggest that using one marker every 0.2 cM is sufficient for genomic selection in this collection of rice breeding materials. RR-BLUP was the best performing statistical method for grain yield where no large effect QTL were detected by GWAS, while for flowering time, where a single very large effect QTL was detected, the non-GS multiple linear regression method outperformed GS models. For plant height, in which four mid-sized QTL were identified by GWAS, random forest produced the most consistently accurate GS models. Our results suggest that GS, informed by GWAS interpretations of genetic architecture and population structure, could become an effective tool for increasing the efficiency of rice breeding as the costs of genotyping continue to decline.

  15. Genomic selection and association mapping in rice (Oryza sativa): effect of trait genetic architecture, training population composition, marker number and statistical model on accuracy of rice genomic selection in elite, tropical rice breeding lines.

    Science.gov (United States)

    Spindel, Jennifer; Begum, Hasina; Akdemir, Deniz; Virk, Parminder; Collard, Bertrand; Redoña, Edilberto; Atlin, Gary; Jannink, Jean-Luc; McCouch, Susan R

    2015-02-01

    Genomic Selection (GS) is a new breeding method in which genome-wide markers are used to predict the breeding value of individuals in a breeding population. GS has been shown to improve breeding efficiency in dairy cattle and several crop plant species, and here we evaluate for the first time its efficacy for breeding inbred lines of rice. We performed a genome-wide association study (GWAS) in conjunction with five-fold GS cross-validation on a population of 363 elite breeding lines from the International Rice Research Institute's (IRRI) irrigated rice breeding program and herein report the GS results. The population was genotyped with 73,147 markers using genotyping-by-sequencing. The training population, statistical method used to build the GS model, number of markers, and trait were varied to determine their effect on prediction accuracy. For all three traits, genomic prediction models outperformed prediction based on pedigree records alone. Prediction accuracies ranged from 0.31 and 0.34 for grain yield and plant height to 0.63 for flowering time. Analyses using subsets of the full marker set suggest that using one marker every 0.2 cM is sufficient for genomic selection in this collection of rice breeding materials. RR-BLUP was the best performing statistical method for grain yield where no large effect QTL were detected by GWAS, while for flowering time, where a single very large effect QTL was detected, the non-GS multiple linear regression method outperformed GS models. For plant height, in which four mid-sized QTL were identified by GWAS, random forest produced the most consistently accurate GS models. Our results suggest that GS, informed by GWAS interpretations of genetic architecture and population structure, could become an effective tool for increasing the efficiency of rice breeding as the costs of genotyping continue to decline.

  16. Genomic Selection and Association Mapping in Rice (Oryza sativa): Effect of Trait Genetic Architecture, Training Population Composition, Marker Number and Statistical Model on Accuracy of Rice Genomic Selection in Elite, Tropical Rice Breeding Lines

    Science.gov (United States)

    Spindel, Jennifer; Begum, Hasina; Akdemir, Deniz; Virk, Parminder; Collard, Bertrand; Redoña, Edilberto; Atlin, Gary; Jannink, Jean-Luc; McCouch, Susan R.

    2015-01-01

    Genomic Selection (GS) is a new breeding method in which genome-wide markers are used to predict the breeding value of individuals in a breeding population. GS has been shown to improve breeding efficiency in dairy cattle and several crop plant species, and here we evaluate for the first time its efficacy for breeding inbred lines of rice. We performed a genome-wide association study (GWAS) in conjunction with five-fold GS cross-validation on a population of 363 elite breeding lines from the International Rice Research Institute's (IRRI) irrigated rice breeding program and herein report the GS results. The population was genotyped with 73,147 markers using genotyping-by-sequencing. The training population, statistical method used to build the GS model, number of markers, and trait were varied to determine their effect on prediction accuracy. For all three traits, genomic prediction models outperformed prediction based on pedigree records alone. Prediction accuracies ranged from 0.31 and 0.34 for grain yield and plant height to 0.63 for flowering time. Analyses using subsets of the full marker set suggest that using one marker every 0.2 cM is sufficient for genomic selection in this collection of rice breeding materials. RR-BLUP was the best performing statistical method for grain yield where no large effect QTL were detected by GWAS, while for flowering time, where a single very large effect QTL was detected, the non-GS multiple linear regression method outperformed GS models. For plant height, in which four mid-sized QTL were identified by GWAS, random forest produced the most consistently accurate GS models. Our results suggest that GS, informed by GWAS interpretations of genetic architecture and population structure, could become an effective tool for increasing the efficiency of rice breeding as the costs of genotyping continue to decline. PMID:25689273

  17. Combining ability and heterotic grouping of early maturing provitamin A maize inbreds across Striga infested and optimal environments

    Directory of Open Access Journals (Sweden)

    Laban Konate

    2017-06-01

    Full Text Available The development, deployment and production of stress tolerant provitamin A maize is crucial to the fight against vitamin A deficiency in sub-Saharan Africa (SSA where maize is a major staple food crop. Fifteen early maturing provitamin A and two early normal yellow endosperm maize inbreds were crossed using the diallel mating design to generate 136 single-cross hybrids. The hybrids were evaluated during 2015 growing season at three locations under two Striga infested and three optimal growing environments in Nigeria. The objectives were to (i determine the combining ability and heterotic groups of early maturing provitamin A inbreds; (ii examine the performance of the inbreds in hybrid combinations across environments and (iii identify early maturing provitamin A inbred testers for use in tropical maize breeding programs. The general combining ability (GCA and specific combining ability (SCA effects were significant for grain yield and most other traits indicating that additive and non-additive genetic effects were important in the inheritance of these characters. Inbreds TZEI 10, TZEIOR 108, and TZEI 17 had significant positive GCA for grain yield. TZEIOR 108, TZEIOR 42, and TZEI 10 had significant negative GCA for Striga damage while TZEIOR 122, TZEIOR 127, TZEIOR 108, and TZEI 10 had significant negative GCA for number of emerged Striga plants. The inbreds were classified based on heterotic groups’ SCA and GCA of grain yield (HSGCA, SCA and GCA of multiple traits (HGCAMT methods into four, three and five heterotic groups, respectively. The inbreds TZEIOR 108, TZEI 10 and TZEI 17 were identified as testers. Hybrids 8, 3, 5, 10 and 1 were identified as high yielding and most stable across environments.

  18. Epitope mapping of the major allergen from Atlantic cod in Spanish population reveals different IgE-binding patterns.

    Science.gov (United States)

    Perez-Gordo, Marina; Pastor-Vargas, Carlos; Lin, Jing; Bardina, Ludmilla; Cases, Barbara; Ibáñez, Maria Dolores; Vivanco, Fernando; Cuesta-Herranz, Javier; Sampson, Hugh A

    2013-07-01

    IgE-epitope mapping of allergens reveal important information about antigen components involved in allergic reactions. The peptide-based microarray immunoassay has been used to map epitopes of some food allergens. We developed a peptide microarray immunoassay to map allergenic epitopes in parvalbumin from Atlantic cod (Gad m 1), the most consumed cod species in Spain. Sera from 13 fish-allergic patients with specific IgE to cod parvalbumin were used. A library of overlapping peptides was synthesized, representing the primary sequence of Gad m 1. Peptides were used to analyze allergen-specific IgE antibodies in patient sera. 100% of the patients recognized one antigenic region of 15 amino acids in length in Gad m 1. This region only partially correlated with one of the three antigenic determinants of Gad c 1 (Allergen M), parvalbumin from Baltic cod (Gadus callarias). In the 3D model of the protein, this region was located on the surface of the protein. We have identified a relevant antigenic region in Gad m 1. This epitope could be considered as a severity marker and provides additional information to improve fish allergy diagnosis and the design of safe immunotherapeutic tools. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Development of next-generation mapping populations: Multi-parent Advanced Generation Inter-Cross (MAGIC) and Marker-Assisted Recurrent Selection (MARS) populations in peanut

    Science.gov (United States)

    Generation Inter-Cross (MAGIC) and Marker-Assisted Recurrent Selection (MARS) have been proposed and used in many crops to dissect complex traits or QTL. MAGIC allows for dissecting genomic structure, and for improving breeding populations by integrating multiple alleles from different parents. MAR...

  20. SNP-based linkage mapping for validation of QTLs for resistance to ascochyta blight in lentil

    Directory of Open Access Journals (Sweden)

    Shimna Sudheesh

    2016-11-01

    Full Text Available Lentil (Lens culinaris Medik. is a self-pollinating, diploid, annual, cool-season, food legume crop that is cultivated throughout the world. Ascochyta blight (AB, caused by Ascochyta lentis Vassilievsky, is an economically important and widespread disease of lentil. Development of cultivars with high levels of durable resistance provides an environmentally acceptable and economically feasible method for AB control. A detailed understanding of the genetic basis of AB resistance is hence highly desirable, in order to obtain insight into the number and influence of resistance genes. Genetic linkage maps based on single nucleotide polymorphisms (SNP and simple sequence repeat (SSR markers have been developed from three recombinant inbred line (RIL populations. The IH x NF map contained 460 loci across 1461.6 cM, while the IH x DIG map contained 329 loci across 1302.5 cM and the third map, NF x DIG contained 330 loci across 1914.1 cM. Data from these maps were combined with a map from a previously published study through use of bridging markers to generate a consensus linkage map containing 689 loci distributed across 7 linkage groups (LGs, with a cumulative length of 2429.61 cM at an average density of one marker per 3.5 cM. Trait dissection of AB resistance was performed for the RIL populations, identifying totals of two and three quantitative trait loci (QTLs explaining 52% and 69% of phenotypic variation for resistance to infection in the IH x DIG and IH x NF populations, respectively. Presence of common markers in the vicinity of the AB_IH1- and AB_IH2.1/AB_IH2.2-containing regions on both maps supports the inference that a common genomic region is responsible for conferring resistance and is associated with the resistant parent, Indianhead. The third QTL was derived from Northfield. Evaluation of markers associated with AB resistance across a diverse lentil germplasm panel revealed that the identity of alleles associated with AB_IH1 predicted

  1. High-Resolution Genome-Wide Linkage Mapping Identifies Susceptibility Loci for BMI in the Chinese Population

    DEFF Research Database (Denmark)

    Zhang, Dong Feng; Pang, Zengchang; Li, Shuxia

    2012-01-01

    The genetic loci affecting the commonly used BMI have been intensively investigated using linkage approaches in multiple populations. This study aims at performing the first genome-wide linkage scan on BMI in the Chinese population in mainland China with hypothesis that heterogeneity in genetic...... linkage could exist in different ethnic populations. BMI was measured from 126 dizygotic twins in Qingdao municipality who were genotyped using high-resolution Affymetrix Genome-Wide Human SNP arrays containing about 1 million single-nucleotide polymorphisms (SNPs). Nonparametric linkage analysis...... in western countries. Multiple loci showing suggestive linkage were found on chromosome 1 (lod score 2.38 at 242 cM), chromosome 8 (2.48 at 95 cM), and chromosome 14 (2.2 at 89.4 cM). The strong linkage identified in the Chinese subjects that is consistent with that found in populations of European origin...

  2. Low Elevation Coastal Zone (LECZ) Urban-Rural Population Estimates, Global Rural-Urban Mapping Project (GRUMP), Alpha Version

    Data.gov (United States)

    National Aeronautics and Space Administration — The Low Elevation Coastal Zone (LECZ) Urban-Rural Estimates consists of country-level estimates of urban, rural and total population and land area country-wide and...

  3. GIS-Mapping and Statistical Analyses to Identify Climate-Vulnerable Communities and Populations Exposed to Superfund Sites

    Science.gov (United States)

    Climate change-related cumulative health risks are expected to be disproportionately greater for overburdened communities, due to differential proximity and exposures to chemical sources and flood zones. Communities and populations vulnerable to climate change-associated impacts ...

  4. HapMap-based study of the DNA repair gene ERCC2 and lung cancer susceptibility in a Chinese population

    DEFF Research Database (Denmark)

    Yin, Jiaoyang; Vogel, Ulla Birgitte; Ma, Yegang

    2009-01-01

    (NER) pathway. To elucidate whether common ERCC2 variants are associated with lung cancer susceptibility, we conducted a case–control study consisting of 339 cases with primary lung cancer and 358 controls matched on age, gender and ethnicity in a Chinese population. Six haplotype tagging single...... polymorphisms. Our results provide evidence to support a role for ERCC2 in lung cancer development in a Chinese population....

  5. Mapping QTLs associated to germination stability following dry-heat treatment in rice seed.

    Science.gov (United States)

    Lee, Seung-Yeob; Kim, Yong-Hwan; Lee, Gang-Seob

    2017-07-01

    Using 164 recombinant inbred lines (RILs) derived from a cross between Milyang 23 (indica/japonica) and Gihobyeo (japonica) in rice, dry-heat tolerance was evaluated for the seeds of parents and RILs, whose dormancy was naturally broken in six months after harvesting. Mapping QTLs associated to dry-heat tolerance was carried out through interval mapping using Qgene 3.0. Seed germination after dry-heat treatments (90 °C for 24 h) showed a significant difference between the two parents, when evaluated for percentage germination and mean germination time. Milyang 23 was highly tolerant to the dry-heat treatment, while Gihobyeo was sensitive. Three QTLs (qDHT 1, qDHT 5, and qDHT 7) conferring the dry-heat tolerance were mapped to chromosomes 1, 5 and 7, respectively. qDHT 1 on chromosome 1 was tightly linked at 4 cM from ME1-1. The phenotypic variation explained by the three QTLs was 27.18% of the total variance in the 164 RIL populations, and the parental additive effects of three QTLs affected the Milyang 23 allele increased dry-heat tolerance. The detection of new QTLs associated with dry-heat tolerance will provide important information for disease and insect control, using dry-heat treatment in organic or low input sustainable agriculture.

  6. Diallel analysis of leaf disease resistance in inbred Brazilian popcorn cultivars.

    Science.gov (United States)

    Vieira, R A; Scapim, C A; Moterle, L M; Tessmann, D J; Conrado, T V; Amaral Júnior, A T

    2009-12-01

    We estimated general and specific combining abilities and examined resistance to northern leaf blight (Exserohilum turcicum) and to gray leaf spot (Cercospora zeae-maydis) in a set of nine inbred popcorn lines. These inbreds were crossed in a complete diallel scheme without reciprocals, which produced 36 F(1) hybrids. Two experiments with a square lattice design and three replications were conducted during the 2008/2009 crop season, in Maringá, PR, Brazil. The severity of northern leaf blight and gray leaf spot was assessed under natural infestation conditions. Data were examined by individual and joint analysis of variance. Individual and joint Griffing's diallel analyses were carried out for adjusted means. General combining ability and specific combining ability were significant (P < 0.10) by the F-test for northern leaf blight and gray leaf spot infestation levels. This denotes that additive and non-additive gene effects both contributed to resistance to these diseases, but that the additive gene effects were more important. Among the inbred lines, P(8) and P(9) gave the highest resistance to northern leaf blight, and P(3) and P(4.3) gave the highest resistance to gray leaf spot. The hybrids P(7.4) x P(8) and P(4.3) x P(9) could be exploited by reciprocal recurrent selection to provide genotypes with both northern leaf blight and gray leaf spot resistance. Significant interaction between general combining ability and crop season (P < 0.10) denotes the importance of environment, even though the disease levels in the hybrids were quite consistent.

  7. Genotypic effects on boron concentrations and response on boron fertilization in maize inbred lines

    Directory of Open Access Journals (Sweden)

    Andrić Luka

    2016-01-01

    Full Text Available Boron (B deficiency in maize can result in barren cobs attributed to silks being nonreceptive which is particularly important for the female parent in seed production. The objectives of this study were 1 to investigate genotypic differences among nine female inbred lines used in seed production for B concentration in ear-leaf and grain, as well as for grain yield and moisture in a three-year experiment (2006-2008 and 2 to determine response and relations among the traits when four of the female inbred lines are treated by foliar boron fertilization - three times in 10-days interval with 0.5% Solubor solution (17.5% B during one growing season (2008. The investigations were performed on Experimental field of Agricultural Institute Osijek, (soil type: eutrical cambisol. Highly significant differences among the nine female inbred lines were detected for B concentration in ear-leaf (from 14.7 to 46.7 mg B kg-1 and grain (from 1.20 to 2.06 mg B kg-1 as well as for grain yield (from 3.33 to 4.83 t ha-1 and grain moisture (from 14.7% to 26.6%. However, there were also significant effects of growing season and the genotype by environment interaction for all four traits. Positive and moderate correlations were found between the boron status in plant and grain yield. Although B concentrations were considerably increased by foliar boron fertilization (averages 41.7 and 125.3 mg B kg-1 in leaves, 1.79 and 2.80 mg B kg-1 in grain, for control and fertilization, respectively, in general grain yield differences among treatments were non-significant. (averages 5.21 and 5.15 t ha-1, respectively.

  8. Susceptibility of the wild-derived inbred CAST/Ei mouse to infection by orthopoxviruses analyzed by live bioluminescence imaging

    Energy Technology Data Exchange (ETDEWEB)

    Americo, Jeffrey L.; Sood, Cindy L.; Cotter, Catherine A.; Vogel, Jodi L.; Kristie, Thomas M.; Moss, Bernard, E-mail: bmoss@nih.gov; Earl, Patricia L., E-mail: pearl@nih.gov

    2014-01-20

    Classical inbred mice are extensively used for virus research. However, we recently found that some wild-derived inbred mouse strains are more susceptible than classical strains to monkeypox virus. Experiments described here indicated that the 50% lethal dose of vaccinia virus (VACV) and cowpox virus (CPXV) were two logs lower in wild-derived inbred CAST/Ei mice than classical inbred BALB/c mice, whereas there was little difference in the susceptibility of the mouse strains to herpes simplex virus. Live bioluminescence imaging was used to follow spread of pathogenic and attenuated VACV strains and CPXV virus from nasal passages to organs in the chest and abdomen of CAST/Ei mice. Luminescence increased first in the head and then simultaneously in the chest and abdomen in a dose-dependent manner. The spreading kinetics was more rapid with VACV than CPXV although the peak photon flux was similar. These data suggest advantages of CAST/Ei mice for orthopoxvirus studies. - Highlights: • Wild-derived inbred CAST/Ei mice are susceptible to vaccinia virus and cowpox virus. • Morbidity and mortality from orthopoxviruses are greater in CAST/Ei than BALB/c mice. • Morbidity and mortality from herpes simplex virus type 1 are similar in both mice. • Imaging shows virus spread from nose to lungs, abdominal organs and brain. • Vaccinia virus spreads more rapidly than cowpox virus.

  9. Towards developing a genetic linkage map of isabgol (Plantago ovata Forsk., a medicinal plant with potent laxative properties

    Directory of Open Access Journals (Sweden)

    Ponnuchamy, Manivel

    2016-07-01

    Full Text Available Genetic linkage maps facilitate the genetic dissection of complex traits and comparative analyses of genome structure, as well as molecular breeding in species of economic importance. Isabgol [Plantago ovata (Forsk.], a medicinal plant with potent laxative properties is used in several traditional systems of Medicines and cultivated in India. We explored the DNA sequences of Isabgol in the Genbank (NCBI and developed over 1500 simple sequence repeats (SSR markers. Some of them were validated through DNA amplification. Transferability of SSRs from wild Plantago species viz., P. major, P. coronopus, P. lancelolata, P. maritina and P. intermida into Plantago ovata was studied. We developed a genetic linkage map using recombinant inbred lines (RILs population which comprises of 30 random amplified polymorphic DNA (RAPD markers spreading across 11 linkage groups (PO-1 to PO-11 with a total map distance of 75.6 cM. The SSR markers developed will have applications in assessing the functional diversity, comparative mapping and other applications in isabgol.

  10. DFT study on the mechanism of InBr3-catalyzed [2+2] cycloaddition ...

    Indian Academy of Sciences (India)

    chemsci

    anism results in the final product (P1) and regenera- tion of the catalyst (InBr3) through a-TS2. In a-TS2, the C2–C4 bond distance is 1.974 Å. The activation free energy for the last step is 10.7 kcal/mol, and the whole catalytic process is exothermic by −14.1 kcal/mol. The intermediate a-IN1 is easy to obtain the product (P1).

  11. Host Defenses in Experimental Scrub Typhus: Delayed-Type Hypersensitivity Responses of Inbred Mice

    OpenAIRE

    Jerrells, Thomas R.; Osterman, Joseph V.

    1982-01-01

    Delayed-type hypersensitivity responses of inbred mice during the course of lethal and chronic infections with strains of Rickettsia tsutsugamushi were evaluated by using the influx of radiolabeled cells into antigen-injected ears. Congenic strains of C3H mice, which previously have been shown to be resistant (C3H/RV) or sensitive (C3H/HeDub) to lethal intraperitoneal infection with the Gilliam strain of rickettsiae, both expressed delayed-type hypersensitivity early in the course of infectio...

  12. Comparative Study of Histopathologic Characterization of Azoxymethane-induced Colon Tumors in Three Inbred Rat Strains

    DEFF Research Database (Denmark)

    Kobæk Larsen, Morten; Fenger, Claus; Hansen, Ket

    2002-01-01

    To obtain controlled genetic variation, colon cancer was chemically induced by use of four subcutaneous injections of azoxymethane (15 mg/kg of body weight/wk) to rats of 3 inbred strains (BDIX/OrlIco, F344/NHsd, WAG/Rij). The selection was based on the availability of established colon cancer cell...... characteristics should resemble the corresponding human tumors. The size of the tumors should be at about 1 cm in diameter, as these tumor cells were intended to be used in future transplantation studies. The two experiments yielded highly reproducible results: histologic evaluation of all colon tumors in all...

  13. SSR marker analysis on genetic variation of M3 from maize inbred lines 48-2 and R08 after irradiation inducement

    International Nuclear Information System (INIS)

    Li Qi; Shi Haichun; Ke Yongpei; Yuan Jichao; Yu Xuejie

    2011-01-01

    Analyzing the biological effects and the genetic variations of maize mutagenic progenies is important to facilitate effective selections and utilization of the mutants. In this study, the genetic variation of 103 mutagenic progenies of M 3 lines of inbred lines 48-2 and R08 with 60 Co γ-rays inducement were evaluated with SSR molecular markers. The results indicated that, the amplitude of polymorphism information content (PIC) of the 48-2 and R08 M 3 lines ranged 0.307 ∼ 0.948 and 0.108 ∼ 0.955, with an average of 0.762 and 0.701, respectively. The amplitude of genetic diversity indexes (H') ranged 0.552 ∼ 2.830 and 0.254 ∼ 3.309, with an average of 1.830 and 1.777, respectively. The average value of genetic similarity coefficient of the 49 M 3 lines of 48-2 with its check (M673) was 0.8194. However, the average value of genetic similarity coefficient of the M 3 lines of R08 with its check (M487) was 0.8373. Based on the genetic similarity coefficient, inbred lines 48-2, R08 and their 101 M 3 lines were clustered in 7 and 5 populations respectively. This phenomenon indicated that massive genetic variation could appear in progenies due to irradiation. The strengthen of selection and utilization of mutants based on the breeding objectives and in accordance with the feature and regularity on genetic variations of main characteristics of mutant lines in various populations could be enhanced in breeding program, to some extent, which can increase the breeding efficiency of irradiation induced mutation in maize. (authors)

  14. SNP discovery and chromosome anchoring provide the first physically-anchored hexaploid oat map and reveal synteny with model species.

    Directory of Open Access Journals (Sweden)

    Rebekah E Oliver

    Full Text Available A physically anchored consensus map is foundational to modern genomics research; however, construction of such a map in oat (Avena sativa L., 2n = 6x = 42 has been hindered by the size and complexity of the genome, the scarcity of robust molecular markers, and the lack of aneuploid stocks. Resources developed in this study include a modified SNP discovery method for complex genomes, a diverse set of oat SNP markers, and a novel chromosome-deficient SNP anchoring strategy. These resources were applied to build the first complete, physically-anchored consensus map of hexaploid oat. Approximately 11,000 high-confidence in silico SNPs were discovered based on nine million inter-varietal sequence reads of genomic and cDNA origin. GoldenGate genotyping of 3,072 SNP assays yielded 1,311 robust markers, of which 985 were mapped in 390 recombinant-inbred lines from six bi-parental mapping populations ranging in size from 49 to 97 progeny. The consensus map included 985 SNPs and 68 previously-published markers, resolving 21 linkage groups with a total map distance of 1,838.8 cM. Consensus linkage groups were assigned to 21 chromosomes using SNP deletion analysis of chromosome-deficient monosomic hybrid stocks. Alignments with sequenced genomes of rice and Brachypodium provide evidence for extensive conservation of genomic regions, and renewed encouragement for orthology-based genomic discovery in this important hexaploid species. These results also provide a framework for high-resolution genetic analysis in oat, and a model for marker development and map construction in other species with complex genomes and limited resources.

  15. QTLs for Woolly Poplar Aphid (Phloeomyzus passerinii L. Resistance Detected in an Inter-Specific Populus deltoides x P. nigra Mapping Population.

    Directory of Open Access Journals (Sweden)

    Giorgia Carletti

    Full Text Available The genus Populus represents one of the most economically important groups of forest trees. It is composed by approximately 30 species used for wood and non-wood products, phytoremediation and biomass. Poplar is subjected to several biological and environmental threats although, compared to annual crops, we know far less about the genetic bases of biotic stress resistance. Woolly poplar aphid (Phloeomyzus passerinii is considered a main pest of cultivated poplars in European and American countries. In this work we present two high density linkage maps in poplar obtained by a genotyping by sequencing (GBS approach and the identification of QTLs involved in Ph. passerinii resistance. A total of 5,667 polymorphic markers (5,606 SNPs and 61 SSRs identified on expressed sequences have been used to genotype 131 plants of an F1 population P ×canadensis obtained by an interspecific mate between Populus deltoides (resistant to woolly poplar aphid and Populus nigra (susceptible to woolly poplar aphid. The two linkage maps, obtained following the two-way pseudo-testcross mapping strategy, have been used to investigate the genetic bases of woolly poplar aphid resistance. One major QTL and two QTLs with minor effects (mapped on LGV, LGXVI and LG XIX explaining the 65.8% of the genetic variance observed in the progeny in response to Ph. passerinii attack were found. The high density coverage of functional markers allowed the identification of three genes belonging to disease resistance pathway as putative candidates for P. deltoides resistance to woolly poplar aphid. This work is the first report on genetic of woolly poplar aphid genetic resistance and the resistant loci associated markers identified represent a valuable tool in resistance poplar breeding programs.

  16. QTLs for Woolly Poplar Aphid (Phloeomyzus passerinii L.) Resistance Detected in an Inter-Specific Populus deltoides x P. nigra Mapping Population.

    Science.gov (United States)

    Carletti, Giorgia; Carra, Andrea; Allegro, Gianni; Vietto, Lorenzo; Desiderio, Francesca; Bagnaresi, Paolo; Gianinetti, Alberto; Cattivelli, Luigi; Valè, Giampiero; Nervo, Giuseppe

    2016-01-01

    The genus Populus represents one of the most economically important groups of forest trees. It is composed by approximately 30 species used for wood and non-wood products, phytoremediation and biomass. Poplar is subjected to several biological and environmental threats although, compared to annual crops, we know far less about the genetic bases of biotic stress resistance. Woolly poplar aphid (Phloeomyzus passerinii) is considered a main pest of cultivated poplars in European and American countries. In this work we present two high density linkage maps in poplar obtained by a genotyping by sequencing (GBS) approach and the identification of QTLs involved in Ph. passerinii resistance. A total of 5,667 polymorphic markers (5,606 SNPs and 61 SSRs) identified on expressed sequences have been used to genotype 131 plants of an F1 population P ×canadensis obtained by an interspecific mate between Populus deltoides (resistant to woolly poplar aphid) and Populus nigra (susceptible to woolly poplar aphid). The two linkage maps, obtained following the two-way pseudo-testcross mapping strategy, have been used to investigate the genetic bases of woolly poplar aphid resistance. One major QTL and two QTLs with minor effects (mapped on LGV, LGXVI and LG XIX) explaining the 65.8% of the genetic variance observed in the progeny in response to Ph. passerinii attack were found. The high density coverage of functional markers allowed the identification of three genes belonging to disease resistance pathway as putative candidates for P. deltoides resistance to woolly poplar aphid. This work is the first report on genetic of woolly poplar aphid genetic resistance and the resistant loci associated markers identified represent a valuable tool in resistance poplar breeding programs.

  17. An Evaluation of Population Density Mapping and Built up Area Estimates in Sri Lanka Using Multiple Methodologies

    Science.gov (United States)

    Engstrom, R.; Soundararajan, V.; Newhouse, D.

    2017-12-01

    In this study we examine how well multiple population density and built up estimates that utilize satellite data compare in Sri Lanka. The population relationship is examined at the Gram Niladhari (GN) level, the lowest administrative unit in Sri Lanka from the 2011 census. For this study we have two spatial domains, the whole country and a 3,500km2 sub-sample, for which we have complete high spatial resolution imagery coverage. For both the entire country and the sub-sample we examine how consistent are the existing publicly available measures of population constructed from satellite imagery at predicting population density? For just the sub-sample we examine how well do a suite of values derived from high spatial resolution satellite imagery predict population density and how does our built up area estimate compare to other publicly available estimates. Population measures were obtained from the Sri Lankan census, and were downloaded from Facebook, WorldPoP, GPW, and Landscan. Percentage built-up area at the GN level was calculated from three sources: Facebook, Global Urban Footprint (GUF), and the Global Human Settlement Layer (GHSL). For the sub-sample we have derived a variety of indicators from the high spatial resolution imagery. Using deep learning convolutional neural networks, an object oriented, and a non-overlapping block, spatial feature approach. Variables calculated include: cars, shadows (a proxy for building height), built up area, and buildings, roof types, roads, type of agriculture, NDVI, Pantex, and Histogram of Oriented Gradients (HOG) and others. Results indicate that population estimates are accurate at the higher, DS Division level but not necessarily at the GN level. Estimates from Facebook correlated well with census population (GN correlation of 0.91) but measures from GPW and WorldPop are more weakly correlated (0.64 and 0.34). Estimates of built-up area appear to be reliable. In the 32 DSD-subsample, Facebook's built- up area measure

  18. Genome-wide association studies in an isolated founder population from the Pacific Island of Kosrae.

    Directory of Open Access Journals (Sweden)

    Jennifer K Lowe

    2009-02-01

    Full Text Available It has been argued that the limited genetic diversity and reduced allelic heterogeneity observed in isolated founder populations facilitates discovery of loci contributing to both Mendelian and complex disease. A strong founder effect, severe isolation, and substantial inbreeding have dramatically reduced genetic diversity in natives from the island of Kosrae, Federated States of Micronesia, who exhibit a high prevalence of obesity and other metabolic disorders. We hypothesized that genetic drift and possibly natural selection on Kosrae might have increased the frequency of previously rare genetic variants with relatively large effects, making these alleles readily detectable in genome-wide association analysis. However, mapping in large, inbred cohorts introduces analytic challenges, as extensive relatedness between subjects violates the assumptions of independence upon which traditional association test statistics are based. We performed genome-wide association analysis for 15 quantitative traits in 2,906 members of the Kosrae population, using novel approaches to manage the extreme relatedness in the sample. As positive controls, we observe association to known loci for plasma cholesterol, triglycerides, and C-reactive protein and to a compelling candidate loci for thyroid stimulating hormone and fasting plasma glucose. We show that our study is well powered to detect common alleles explaining >/=5% phenotypic variance. However, no such large effects were observed with genome-wide significance, arguing that even in such a severely inbred population, common alleles typically have modest effects. Finally, we show that a majority of common variants discovered in Caucasians have indistinguishable effect sizes on Kosrae, despite the major differences in population genetics and environment.

  19. Inheritance Analysis and QTL Mapping of Rice Starch Viscosity (Rapid Visco Analyzer Profile Characteristics

    Directory of Open Access Journals (Sweden)

    Qiao-feng ZHANG

    2008-09-01

    Full Text Available The rice starch viscosity characteristics, which can be indicated by Rapid Visco Analyzer profile (RVA profile, have been proved useful for the evaluation of cooking and eating quality in rice breeding program. To study the inheritance of the RVA profile, an F2 population of Wuyujing 3/Aichi 106 was used. The results indicated that the peak viscosity (PKV was a typical quantitative character, and the hot paste viscosity (HPV, cool paste viscosity (CPV, setback viscosity (SBV, breakdown viscosity (BDV, and consistence viscosity (CSV might be controlled by one major gene and several minor genes. To elucidate the genetic basis of the paste viscosity characteristics, a recombinant inbred line (RIL population derived from Nikken 2/Milyang 23 and its genetic linkage map were used to map the QTLs controlling RVA profiles in 2005 and 2006. A total of 34 QTLs distributed on chromosomes 1, 2, 3, 4, 6, 7 and 8 were detected, including 19 and 15 QTLs in 2005 and 2006, respectively. Eight QTLs were both detected in the two years, qHPV6, qCPV6, qCSV6, qSBV6, and qBDV6 were located on chromosome 6, while qHPV2, qCSV2, and qCPV2 were on chromosome 2.

  20. Construction of 2 intraspecific linkage maps and identification of resistance QTLs for Phytophthora capsici root-rot and foliar-blight diseases of pepper (Capsicum annuum L.).

    Science.gov (United States)

    Ogundiwin, Ebenezer A; Berke, Terry F; Massoudi, Mark; Black, Lowell L; Huestis, Gordon; Choi, Doil; Lee, Sanghyeob; Prince, James P

    2005-08-01

    Two linkage maps of pepper were constructed and used to identify quantitative trait loci (QTLs) conferring resistance to Phytophthora capsici. Inoculations were done with 7 isolates: 3 from Taiwan, 3 from California, and 1 from New Mexico. The first map was constructed from a set of recombinant inbred lines (RILs) of the PSP-11 (susceptible) x PI201234 (resistant) cross; and the second map was from a set of F(2) lines of the Joe E. Parker' (susceptible) x 'Criollo de Morelos 334' (resistant) cross. The RIL map covered 1466.1 cM of the pepper genome, and it consisted of 144 markers -- 91 amplified fragment length polymorphisms (AFLPs), 34 random amplified polymorphic DNA (RAPDs), 15 simple sequence repeats (SSRs), 1 sequence characterized amplified region (SCAR), and 3 morphological markers -- distributed over 17 linkage groups. The morphological markers mapped on this population were erect fruit habit (up), elongated fruit shape (fs(e)), and fasciculate fruit clusters (fa). The F(2) map consisted of 113 markers (51 AFLPs, 45 RAPDs, 14 SSRs, and 3 SCARs) distributed in 16 linkage groups, covering a total of 1089.2 cM of the pepper genome. Resistance to both root rot and foliar blight were evaluated in the RIL population using the 3 Taiwan isolates; the remaining isolates were used for the root-rot test only. Sixteen chromosomal regions of the RIL map contained single QTLs or clusters of resistance QTLs that had an effect on root rot and (or) foliar blight, revealing a complex set of genetics involved in resistance to P. capsici. Five QTLs were detected in the F(2) map that had an effect on resistance to root rot.

  1. Correlations between the contents of phytic acid and inorganic phosphorous and downy mildew resistance of corn inbred lines

    Directory of Open Access Journals (Sweden)

    Pantipa Na Chiangmai

    2015-10-01

    Full Text Available Seeds of corn inbred lines collected at the National Corn and Sorghum Research Center (NCSRC, Kasetsart University, were analyzed to determine the contents of phytic acid (PA and inorganic phosphorous (InP. These 28 and 29 inbred lines were cultivated at the NCSRC (in the 2008 late rainy season and 2009 early rainy season to evaluate their resistance to corn downy mildew caused by Peronosclerospora sorghi. Results showed that the values of the PA, InP contents and downy mildew infection were statistically different among these inbred lines in both seasons. However, there were no correlations between the contents of either PA or InP and downy mildew infection.

  2. Quantitative trait loci mapping of heat tolerance in a doubled haploid population of broccoli using genotyping-by-sequencing

    Science.gov (United States)

    Broccoli is a cool weather vegetable crop with a vernalization requirement to initiate and maintain floral development. Breeding for heat tolerance in broccoli has the potential to both expand viable production areas and extend the growing season. A doubled haploid (DH) population of broccoli (Bras...

  3. Population bulk segregant mapping uncovers resistance mutations and the mode of action of a chitin synthesis inhibitor in arthropods

    NARCIS (Netherlands)

    Van Leeuwen, T.; Demaeght, P.; Osborne, E.J.; Dermauw, W.; Gohlke, S.; Nauen, R.; Grbić, M.; Tirry, L.; Merzendorfer, H.; Clark, R.M.

    2012-01-01

    Because of its importance to the arthropod exoskeleton, chitin biogenesis is an attractive target for pest control. This point is demonstrated by the economically important benzoylurea compounds that are in wide use as highly specific agents to control insect populations. Nevertheless, the target

  4. Illicit Drug Users in the Tanzanian Hinterland: Population Size Estimation Through Key Informant-Driven Hot Spot Mapping.

    Science.gov (United States)

    Ndayongeje, Joel; Msami, Amani; Laurent, Yovin Ivo; Mwankemwa, Syangu; Makumbuli, Moza; Ngonyani, Alois M; Tiberio, Jenny; Welty, Susie; Said, Christen; Morris, Meghan D; McFarland, Willi

    2018-02-12

    We mapped hot spots and estimated the numbers of people who use drugs (PWUD) and who inject drugs (PWID) in 12 regions of Tanzania. Primary (ie, current and past PWUD) and secondary (eg, police, service providers) key informants identified potential hot spots, which we visited to verify and count the number of PWUD and PWID present. Adjustments to counts and extrapolation to regional estimates were done by local experts through iterative rounds of discussion. Drug use, specifically cocaine and heroin, occurred in all regions. Tanga had the largest numbers of PWUD and PWID (5190 and 540, respectively), followed by Mwanza (3300 and 300, respectively). Findings highlight the need to strengthen awareness of drug use and develop prevention and harm reduction programs with broader reach in Tanzania. This exercise provides a foundation for understanding the extent and locations of drug use, a baseline for future size estimations, and a sampling frame for future research.

  5. Mapping the social network: tracking lice in a wild primate (Microcebus rufus population to infer social contacts and vector potential

    Directory of Open Access Journals (Sweden)

    Zohdy Sarah

    2012-03-01

    Full Text Available Abstract Background Studies of host-parasite interactions have the potential to provide insights into the ecology of both organisms involved. We monitored the movement of sucking lice (Lemurpediculus verruculosus, parasites that require direct host-host contact to be transferred, in their host population of wild mouse lemurs (Microcebus rufus. These lemurs live in the rainforests of Madagascar, are small (40 g, arboreal, nocturnal, solitary foraging primates for which data on population-wide interactions are difficult to obtain. We developed a simple, cost effective method exploiting the intimate relationship between louse and lemur, whereby individual lice were marked, without removal from their host, with an individualized code, and tracked throughout the lemur population. We then tested the hypotheses that 1 the frequency of louse transfers, and thus interactions, would decrease with increasing distance between paired individual lemurs; 2 due to host polygynandry, social interactions and hence louse transfers would increase during the onset of the breeding season; and 3 individual mouse lemurs would vary in their contributions to the spread of lice. Results We show that louse transfers involved 43.75% of the studied lemur population, exclusively males. Louse transfers peaked during the breeding season, perhaps due to increased social interactions between lemurs. Although trap-based individual lemur ranging patterns are restricted, louse transfer rate does not correlate with the distance between lemur trapping locales, indicating wider host ranging behavior and a greater risk of rapid population-wide pathogen transmission than predicted by standard trapping data alone. Furthermore, relatively few lemur individuals contributed disproportionately to the rapid spread of lice throughout the population. Conclusions Using a simple method, we were able to visualize exchanges of lice in a population of cryptic wild primates. This method not only

  6. Mapping the social network: tracking lice in a wild primate (Microcebus rufus) population to infer social contacts and vector potential.

    Science.gov (United States)

    Zohdy, Sarah; Kemp, Addison D; Durden, Lance A; Wright, Patricia C; Jernvall, Jukka

    2012-03-26

    Studies of host-parasite interactions have the potential to provide insights into the ecology of both organisms involved. We monitored the movement of sucking lice (Lemurpediculus verruculosus), parasites that require direct host-host contact to be transferred, in their host population of wild mouse lemurs (Microcebus rufus). These lemurs live in the rainforests of Madagascar, are small (40 g), arboreal, nocturnal, solitary foraging primates for which data on population-wide interactions are difficult to obtain. We developed a simple, cost effective method exploiting the intimate relationship between louse and lemur, whereby individual lice were marked, without removal from their host, with an individualized code, and tracked throughout the lemur population. We then tested the hypotheses that 1) the frequency of louse transfers, and thus interactions, would decrease with increasing distance between paired individual lemurs; 2) due to host polygynandry, social interactions and hence louse transfers would increase during the onset of the breeding season; and 3) individual mouse lemurs would vary in their contributions to the spread of lice. We show that louse transfers involved 43.75% of the studied lemur population, exclusively males. Louse transfers peaked during the breeding season, perhaps due to increased social interactions between lemurs. Although trap-based individual lemur ranging patterns are restricted, louse transfer rate does not correlate with the distance between lemur trapping locales, indicating wider host ranging behavior and a greater risk of rapid population-wide pathogen transmission than predicted by standard trapping data alone. Furthermore, relatively few lemur individuals contributed disproportionately to the rapid spread of lice throughout the population. Using a simple method, we were able to visualize exchanges of lice in a population of cryptic wild primates. This method not only provided insight into the previously unseen parasite

  7. A Maize Inbred Exhibits Resistance Against Western Corn Rootwoorm, Diabrotica virgifera virgifera.

    Science.gov (United States)

    Castano-Duque, Lina; Loades, Kenneth W; Tooker, John F; Brown, Kathleen M; Paul Williams, W; Luthe, Dawn S

    2017-12-01

    Insect resistance against root herbivores like the western corn rootworm (WCR, Diabrotica virgifera virgifera) is not well understood in non-transgenic maize. We studied the responses of two American maize inbreds, Mp708 and Tx601, to WCR infestation using biomechanical, molecular, biochemical analyses, and laser ablation tomography. Previous studies performed on several inbreds indicated that these two maize genotypes differed in resistance to pests including fall armyworm (Spodoptera frugiperda) and WCR. Our data confirmed that Mp708 shows resistance against WCR, and demonstrates that the resistance mechanism is based in a multi-trait phenotype that includes increased resistance to cutting in nodal roots, stable root growth during insect infestation, constitutive and induced expression of known herbivore-defense genes, including ribosomal inhibitor protein 2 (rip2), terpene synthase 23 (tps23) and maize insect resistance cysteine protease-1 (mir1), as well high constitutive levels of jasmonic acid and production of (E)-β-caryophyllene. In contrast, Tx601 is susceptible to WCR. These findings will facilitate the use of Mp708 as a model to explore the wide variety of mechanisms and traits involved in plant defense responses and resistance to herbivory by insects with several different feeding habits.

  8. Proteomic Analysis of Silk Viability in Maize Inbred Lines and Their Corresponding Hybrids.

    Directory of Open Access Journals (Sweden)

    Zhihui Ma

    Full Text Available A long period of silk viability is critical for a good seed setting rate in maize (Zea mays L., especially for inbred lines and hybrids with a long interval between anthesis and silking. To explore the molecular mechanism of silk viability and its heterosis, three inbred lines with different silk viability characteristics (Xun928, Lx9801, and Zong3 and their two hybrids (Xun928×Zong3 and Lx9801×Zong3 were analyzed at different developmental stages by a proteomic method. The differentially accumulated proteins were identified by mass spectrometry and classified into metabolism, protein biosynthesis and folding, signal transduction and hormone homeostasis, stress and defense responses, and cellular processes. Proteins involved in nutrient (methionine and energy (ATP supply, which support the pollen tube growth in the silk, were important for silk viability and its heterosis. The additive and dominant effects at a single locus, as well as complex epistatic interactions at two or more loci in metabolic pathways, were the primary contributors for mid-parent heterosis of silk viability. Additionally, the proteins involved in the metabolism of anthocyanins, which indirectly negatively regulate local hormone accumulation, were also important for the mid-parent heterosis of silk viability. These results also might imply the developmental dependence of heterosis, because many of the differentially accumulated proteins made distinct contributions to the heterosis of silk viability at specific developmental stages.

  9. Unpredictable chronic mild stress differentially impairs social and contextual discrimination learning in two inbred mouse strains.

    Directory of Open Access Journals (Sweden)

    Michiel van Boxelaere

    Full Text Available Alterations in the social and cognitive domain are considered important indicators for increased disability in many stress-related disorders. Similar impairments have been observed in rodents chronically exposed to stress, mimicking potential endophenotypes of stress-related psychopathologies such as major depression disorder (MDD, anxiety, conduct disorder, and posttraumatic stress disorder (PTSD. Data from numerous studies suggest that deficient plasticity mechanisms in hippocampus (HC and prefrontal cortex (PFC might underlie these social and cognitive deficits. Specifically, stress-induced deficiencies in neural plasticity have been associated with a hypodopaminergic state and reduced neural plasticity persistence. Here we assessed the effects of unpredictable chronic mild stress (UCMS on exploratory, social and cognitive behavior of females of two inbred mouse strains (C57BL/6J and DBA/2J that differ in their dopaminergic profile. Exposure to chronic stress resulted in impaired circadian rhythmicity, sociability and social cognition in both inbred strains, but differentially affected activity patterns and contextual discrimination performance. These stress-induced behavioral impairments were accompanied by reduced expression levels of brain derived neurotrophic factor (BDNF in the prefrontal cortex. The strain-specific cognitive impairment was coexistent with enhanced plasma corticosterone levels and reduced expression of genes related to dopamine signaling in hippocampus. These results underline the importance of assessing different strains with multiple test batteries to elucidate the neural and genetic basis of social and cognitive impairments related to chronic stress.

  10. Agrobacterium- and Biolistic-Mediated Transformation of Maize B104 Inbred.

    Science.gov (United States)

    Raji, Jennifer A; Frame, Bronwyn; Little, Daniel; Santoso, Tri Joko; Wang, Kan

    2018-01-01

    Genetic transformation of maize inbred genotypes remains non-routine for many laboratories due to variations in cell competency to induce embryogenic callus, as well as the cell's ability to receive and incorporate transgenes into the genome. This chapter describes two transformation protocols using Agrobacterium- and biolistic-mediated methods for gene delivery. Immature zygotic embryos of maize inbred B104, excised from ears harvested 10-14 days post pollination, are used as starting explant material. Disarmed Agrobacterium strains harboring standard binary vectors and the biolistic gun system Bio-Rad PDS-1000/He are used as gene delivery systems. The herbicide resistant bar gene and selection agent bialaphos are used for identifying putative transgenic type I callus events. Using the step-by-step protocols described here, average transformation frequencies (number of bialaphos resistant T 0 callus events per 100 explants infected or bombarded) of 4% and 8% can be achieved using the Agrobacterium- and biolistic-mediated methods, respectively. An estimated duration of 16-21 weeks is needed using either protocol from the start of transformation experiments to obtaining putative transgenic plantlets with established roots. In addition to laboratory in vitro procedures, detailed greenhouse protocols for producing immature ears as transformation starting material and caring for transgenic plants for seed production are also described.

  11. Cocaine locomotor activation, sensitization and place preference in six inbred strains of mice

    Directory of Open Access Journals (Sweden)

    Grabowski-Boase Laura

    2011-08-01

    Full Text Available Abstract Background The expanding set of genomics tools available for inbred mouse strains has renewed interest in phenotyping larger sets of strains. The present study aims to explore phenotypic variability among six commonly-used inbred mouse strains to both the rewarding and locomotor stimulating effects of cocaine in a place conditioning task, including several strains or substrains that have not yet been characterized for some or all of these behaviors. Methods C57BL/6J (B6, BALB/cJ (BALB, C3H/HeJ (C3H, DBA/2J (D2, FVB/NJ (FVB and 129S1/SvImJ (129 mice were tested for conditioned place preference to 20 mg/kg cocaine. Results Place preference was observed in most strains with the exception of D2 and 129. All strains showed a marked increase in locomotor activity in response to cocaine. In BALB mice, however, locomotor activation was context-dependent. Locomotor sensitization to repeated exposure to cocaine was most significant in 129 and D2 mice but was absent in FVB mice. Conclusions Genetic correlations suggest that no significant correlation between conditioned place preference, acute locomotor activation, and locomotor sensitization exists among these strains indicating that separate mechanisms underlie the psychomotor and rewarding effects of cocaine.

  12. Profiling polyphenols of two diploid strawberry (Fragaria vesca) inbred lines using UHPLC-HRMS(n.).

    Science.gov (United States)

    Sun, Jianghao; Liu, Xianjin; Yang, Tianbao; Slovin, Janet; Chen, Pei

    2014-03-01

    Phenolic compounds in the fruits of two diploid strawberries (Fragaria vesca f. semperflorens) inbred lines-Ruegen F7-4 (a red-fruited genotype) and YW5AF7 (a yellow-fruited genotype) were characterised using ultra-high-performance liquid chromatography coupled with tandem high-resolution mass spectrometry (UHPLC-HRMS(n)). The changes of anthocyanin composition during fruit development and between Ruegen F7-4 and YW5AF7 were studied. About 67 phenolic compounds, including taxifolin 3-O-arabinoside, glycosides of quercetin, kaempferol, cyanidin, pelargonidin, peonidin, ellagic acid derivatives, and other flavonols were identified in these two inbred lines. Compared to the regular octoploid strawberry, unique phenolic compounds were found in F. vesca fruits, such as taxifolin 3-O-arabinoside (both) and peonidin 3-O-malonylglucoside (Ruegen F7-4). The results provide the basis for comparative analysis of polyphenolic compounds in yellow and red diploid strawberries, as well as with the cultivated octoploid strawberries. Published by Elsevier Ltd.

  13. Myelogenous leukemia in adult inbred MHC-defined miniature swine: a model for human myeloid leukemias.

    Science.gov (United States)

    Duran-Struuck, Raimon; Cho, Patricia S; Teague, Alexander G S; Fishman, Brian; Fishman, Aaron S; Hanekamp, John S; Moran, Shannon G; Wikiel, Krzysztof J; Ferguson, Kelly K; Lo, Diana P; Duggan, Michael; Arn, J Scott; Billiter, Bob; Horner, Ben; Houser, Stuart; Yeap, Beow Yong; Westmoreland, Susan V; Spitzer, Thomas R; McMorrow, Isabel M; Sachs, David H; Bronson, Roderick T; Huang, Christene A

    2010-06-15

    This manuscript reports on five cases of spontaneous myelogenous leukemia, similar to human disease, occurring within highly inbred, histocompatible sublines of Massachusetts General Hospital (MGH) MHC-defined miniature swine. In cases where a neoplasm was suspected based on clinical observations, samples were obtained for complete blood count, peripheral blood smear, and flow cytometric analysis. Animals confirmed to have neoplasms were euthanized and underwent necropsy. Histological samples were obtained from abnormal tissues and suspect lesions. The phenotype of the malignancies was assessed by flow cytometric analysis of processed peripheral blood mononuclear cells and affected tissues. Five cases of spontaneous myeloid leukemia were identified in adult animals older than 30 months of age. All animals presented with symptoms of weight loss, lethargy, and marked leukocytosis. At autopsy, all animals had systemic disease involvement and presented with severe hepatosplenomegaly. Three of the five myelogenous leukemias have successfully been expanded in vitro. The clustered incidence of disease in this closed herd suggests that genetic factors may be contributing to disease development. Myelogenous leukemia cell lines established from inbred sublines of MGH MHC-defined miniature swine have the potential to be utilized as a model to evaluate therapies of human leukemia. Copyright 2009 Elsevier B.V. All rights reserved.

  14. Unpredictable chronic mild stress differentially impairs social and contextual discrimination learning in two inbred mouse strains.

    Science.gov (United States)

    van Boxelaere, Michiel; Clements, Jason; Callaerts, Patrick; D'Hooge, Rudi; Callaerts-Vegh, Zsuzsanna

    2017-01-01

    Alterations in the social and cognitive domain are considered important indicators for increased disability in many stress-related disorders. Similar impairments have been observed in rodents chronically exposed to stress, mimicking potential endophenotypes of stress-related psychopathologies such as major depression disorder (MDD), anxiety, conduct disorder, and posttraumatic stress disorder (PTSD). Data from numerous studies suggest that deficient plasticity mechanisms in hippocampus (HC) and prefrontal cortex (PFC) might underlie these social and cognitive deficits. Specifically, stress-induced deficiencies in neural plasticity have been associated with a hypodopaminergic state and reduced neural plasticity persistence. Here we assessed the effects of unpredictable chronic mild stress (UCMS) on exploratory, social and cognitive behavior of females of two inbred mouse strains (C57BL/6J and DBA/2J) that differ in their dopaminergic profile. Exposure to chronic stress resulted in impaired circadian rhythmicity, sociability and social cognition in both inbred strains, but differentially affected activity patterns and contextual discrimination performance. These stress-induced behavioral impairments were accompanied by reduced expression levels of brain derived neurotrophic factor (BDNF) in the prefrontal cortex. The strain-specific cognitive impairment was coexistent with enhanced plasma corticosterone levels and reduced expression of genes related to dopamine signaling in hippocampus. These results underline the importance of assessing different strains with multiple test batteries to elucidate the neural and genetic basis of social and cognitive impairments related to chronic stress.

  15. Genetic analysis of arsenic accumulation in maize using QTL mapping

    Science.gov (United States)

    Fu, Zhongjun; Li, Weihua; Xing, Xiaolong; Xu, Mengmeng; Liu, Xiaoyang; Li, Haochuan; Xue, Yadong; Liu, Zonghua; Tang, Jihua

    2016-02-01

    Arsenic (As) is a toxic heavy metal that can accumulate in crops and poses a threat to human health. The genetic mechanism of As accumulation is unclear. Herein, we used quantitative trait locus (QTL) mapping to unravel the genetic basis of As accumulation in a maize recombinant inbred line population derived from the Chinese crossbred variety Yuyu22. The kernels had the lowest As content among the different maize tissues, followed by the axes, stems, bracts and leaves. Fourteen QTLs were identified at each location. Some of these QTLs were identified in different environments and were also detected by joint analysis. Compared with the B73 RefGen v2 reference genome, the distributions and effects of some QTLs were closely linked to those of QTLs detected in a previous study; the QTLs were likely in strong linkage disequilibrium. Our findings could be used to help maintain maize production to satisfy the demand for edible corn and to decrease the As content in As-contaminated soil through the selection and breeding of As pollution-safe cultivars.

  16. Confirmation and fine-mapping of a major QTL for resistance to infectious pancreatic necrosis in Atlantic salmon (Salmo salar: population-level associations between markers and trait

    Directory of Open Access Journals (Sweden)

    Moen Thomas

    2009-08-01

    Full Text Available Abstract Background Infectious pancreatic necrosis (IPN is one of the most prevalent and economically devastating diseases in Atlantic salmon (Salmo salar farming worldwide. The disease causes large mortalities at both the fry- and post-smolt stages. Family selection for increased IPN resistance is performed through the use of controlled challenge tests, where survival rates of sib-groups are recorded. However, since challenge-tested animals cannot be used as breeding candidates, within-family selection is not performed and only half of the genetic variation for IPN resistance is being exploited. DNA markers linked to quantitative trait loci (QTL affecting IPN resistance would therefore be a powerful selection tool. The aim of this study was to identify and fine-map QTL for IPN-resistance in Atlantic salmon, for use in marker-assisted selection to increase the rate of genetic improvement for this trait. Results A genome scan was carried out using 10 large full-sib families of challenge-tested Atlantic salmon post-smolts and microsatellite markers distributed across the genome. One major QTL for IPN-resistance was detected, explaining 29% and 83% of the phenotypic and genetic variances, respectively. This QTL mapped to the same location as a QTL recently detected in a Scottish Atlantic salmon population. The QTL was found to be segregating in 10 out of 20 mapping parents, and subsequent fine-mapping with additional markers narrowed the QTL peak to a 4 cM region on linkage group 21. Challenge-tested fry were used to show that the QTL had the same effect on fry as on post-smolt, with the confidence interval for QTL position in fry overlapping the confidence interval found in post-smolts. A total of 178 parents were tested for segregation of the QTL, identifying 72 QTL-heterozygous parents. Genotypes at QTL-heterozygous parents were used to determine linkage phases between alleles at the underlying DNA polymorphism and alleles at single markers or

  17. Fine mapping and replication of QTL in outbred chicken advanced intercross lines

    Directory of Open Access Journals (Sweden)

    Andersson Leif

    2011-01-01

    Full Text Available Abstract Background Linkage mapping is used to identify genomic regions affecting the expression of complex traits. However, when experimental crosses such as F2 populations or backcrosses are used to map regions containing a Quantitative Trait Locus (QTL, the size of the regions identified remains quite large, i.e. 10 or more Mb. Thus, other experimental strategies are needed to refine the QTL locations. Advanced Intercross Lines (AIL are produced by repeated intercrossing of F2 animals and successive generations, which decrease linkage disequilibrium in a controlled manner. Although this approach is seen as promising, both to replicate QTL analyses and fine-map QTL, only a few AIL datasets, all originating from inbred founders, have been reported in the literature. Methods We have produced a nine-generation AIL pedigree (n = 1529 from two outbred chicken lines divergently selected for body weight at eight weeks of age. All animals were weighed at eight weeks of age and genotyped for SNP located in nine genomic regions where significant or suggestive QTL had previously been detected in the F2 population. In parallel, we have developed a novel strategy to analyse the data that uses both genotype and pedigree information of all AIL individuals to replicate the detection of and fine-map QTL affecting juvenile body weight. Results Five of the nine QTL detected with the original F2 population were confirmed and fine-mapped with the AIL, while for the remaining four, only suggestive evidence of their existence was obtained. All original QTL were confirmed as a single locus, except for one, which split into two linked QTL. Conclusions Our results indicate that many of the QTL, which are genome-wide significant or suggestive in the analyses of large intercross populations, are true effects that can be replicated and fine-mapped using AIL. Key factors for success are the use of large populations and powerful statistical tools. Moreover, we believe that

  18. Fine mapping and replication of QTL in outbred chicken advanced intercross lines.

    Science.gov (United States)

    Besnier, Francois; Wahlberg, Per; Rönnegård, Lars; Ek, Weronica; Andersson, Leif; Siegel, Paul B; Carlborg, Orjan

    2011-01-17

    Linkage mapping is used to identify genomic regions affecting the expression of complex traits. However, when experimental crosses such as F(2) populations or backcrosses are used to map regions containing a Quantitative Trait Locus (QTL), the size of the regions identified remains quite large, i.e. 10 or more Mb. Thus, other experimental strategies are needed to refine the QTL locations. Advanced Intercross Lines (AIL) are produced by repeated intercrossing of F(2) animals and successive generations, which decrease linkage disequilibrium in a controlled manner. Although this approach is seen as promising, both to replicate QTL analyses and fine-map QTL, only a few AIL datasets, all originating from inbred founders, have been reported in the literature. We have produced a nine-generation AIL pedigree (n = 1529) from two outbred chicken lines divergently selected for body weight at eight weeks of age. All animals were weighed at eight weeks of age and genotyped for SNP located in nine genomic regions where significant or suggestive QTL had previously been detected in the F(2) population. In parallel, we have developed a novel strategy to analyse the data that uses both genotype and pedigree information of all AIL individuals to replicate the detection of and fine-map QTL affecting juvenile body weight. Five of the nine QTL detected with the original F(2) population were confirmed and fine-mapped with the AIL, while for the remaining four, only suggestive evidence of their existence was obtained. All original QTL were confirmed as a single locus, except for one, which split into two linked QTL. Our results indicate that many of the QTL, which are genome-wide significant or suggestive in the analyses of large intercross populations, are true effects that can be replicated and fine-mapped using AIL. Key factors for success are the use of large populations and powerful statistical tools. Moreover, we believe that the statistical methods we have developed to efficiently

  19. Genetic architecture of the F7 gene in a Spanish population: implication for mapping complex diseases and for functional assays.

    Science.gov (United States)

    Sabater-Lleal, M; Almasy, L; Martínez-Marchán, E; Martínez-Sánchez, E; Souto, R; Blangero, J; Souto, Jc; Fontcuberta, J; Soria, J M

    2006-05-01

    Delineating the genetic variability of loci coding for complex diseases helps to understand the individual variation in disease susceptibility and drug response. We present the allelic architecture of the F7 gene. This gene is the major determinant of FVII plasma levels, and these plasma levels constitute an important intermediate risk factor for cardiovascular disease. As part of the Genetic Analysis of Idiopathic Thrombophila Project, we completely re-sequenced the F7 locus (promoter, exons, introns, and 3'-untranslated region) in 40 unrelated individuals. We found 49 polymorphisms with only two amino acid changes suggesting that regulatory non-coding and intronic variants are responsible for the FVII variability. These results are important for mapping susceptibility alleles of complex diseases, because differences in pair-wise linkage disequilibrium patterns between DNA variants and haplotype frequency distributions may help to detect disease-associated alleles. In addition, we present the results of an in silico search that established genomic comparisons among different species. In conclusion, our study of the F7 DNA sequence variations is an example of a strategy for analyzing the genetic architecture of a quantitative trait locus. Furthermore, it provides a model for future analyses of genetic factors that contribute to the susceptibility of complex diseases in humans.

  20. Statistical Parametric Mapping of HR-pQCT Images: A Tool for Population-Based Local Comparisons of Micro-Scale Bone Features.

    Science.gov (United States)

    Carballido-Gamio, Julio; Bonaretti, Serena; Kazakia, Galateia J; Khosla, Sundeep; Majumdar, Sharmila; Lang, Thomas F; Burghardt, Andrew J

    2017-04-01

    HR-pQCT enables in vivo multi-parametric assessments of bone microstructure in the distal radius and distal tibia. Conventional HR-pQCT image analysis approaches summarize bone parameters into global scalars, discarding relevant spatial information. In this work, we demonstrate the feasibility and reliability of statistical parametric mapping (SPM) techniques for HR-pQCT studies, which enable population-based local comparisons of bone properties. We present voxel-based morphometry (VBM) to assess trabecular and cortical bone voxel-based features, and a surface-based framework to assess cortical bone features both in cross-sectional and longitudinal studies. In addition, we present tensor-based morphometry (TBM) to assess trabecular and cortical bone structural changes. The SPM techniques were evaluated based on scan-rescan HR-pQCT acquisitions with repositioning of the distal radius and distal tibia of 30 subjects. For VBM and surface-based SPM purposes, all scans were spatially normalized to common radial and tibial templates, while for TBM purposes, rescans (follow-up) were spatially normalized to their corresponding scans (baseline). VBM was evaluated based on maps of local bone volume fraction (BV/TV), homogenized volumetric bone mineral density (vBMD), and homogenized strain energy density (SED) derived from micro-finite element analysis; while the cortical bone framework was evaluated based on surface maps of cortical bone thickness, vBMD, and SED. Voxel-wise and vertex-wise comparisons of bone features were done between the groups of baseline and follow-up scans. TBM was evaluated based on mean square errors of determinants of Jacobians at baseline bone voxels. In both anatomical sites, voxel- and vertex-wise uni- and multi-parametric comparisons yielded non-significant differences, and TBM showed no artefactual bone loss or apposition. The presented SPM techniques demonstrated robust specificity thus warranting their application in future clinical HR

  1. Mapping the Human Planet: Integrating Settlement, Infrastructure, and Population Data to Support Sustainable Development, Climate, and Disaster Data Needs

    Science.gov (United States)

    Chen, R. S.; de Sherbinin, A. M.; Yetman, G.; Downs, R. R.

    2017-12-01

    A central issue in international efforts to address climate change, large-scale disaster risk, and overall sustainable development is the exposure of human settlements and population to changing climate patterns and a range of geological, climatological, technological, and other hazards. The present and future location of human activities is also important in mitigation and adaptation to climate change, and to ensuring that we "leave no one behind" in achieving the Sustainable Development Goals adopted by the international community in September 2015. The extent and quality of built infrastructure are key factors in the mortality, morbidity, and economic impacts of disasters, and are simultaneously essential to sustainable development. Earth observations have great potential to improve the coverage, consistency, timeliness, and richness of data on settlements, infrastructure, and population, in ways that complement existing and emerging forms of socioeconomic data collection such as censuses, surveys, and cell phone and Internet traffic. Night-time lights from the Suomi-NPP satellite may be able to provide near real-time data on occupance and economic activity. New "big data" capabilities make it possible to rapidly process high-resolution (50-cm) imagery to detect structures and changes in structures, especially in rural areas where other data are limited. A key challenge is to ensure that these types of data can be translated into forms useful in a range of applications and for diverse user communities, including national statistical offices, local government planners, development and humanitarian organizations, community groups, and the private sector. We report here on efforts, in coordination with the GEO Human Planet Initiative, to develop new data on settlements, infrastructure, and population, together with open data services and tools, to support disaster risk assessment, climate vulnerability analysis, and sustainable development decision making.

  2. Molecular Mapping of QTLs for Yield and Yield-Related Traits in Oryza sativa cv Swarna × O. nivara (IRGC81848 Backcross Population

    Directory of Open Access Journals (Sweden)

    B.P. MALLIKARJUNA SWAMY

    2011-09-01

    Full Text Available Advanced backcross QTL analysis was used to identify QTLs for seven yield and yield-related traits in a BC2F2 population from the cross between a popular Oryza sativa cv Swarna and O. nivara IRGC81848. Transgressive segregants with more than 15% increased effect over Swarna were observed for all the traits except days to heading and days to 50% flowering. Thirty QTLs were detected for seven yield and yield-related traits using interval and composite interval mapping. Enhancing alleles at 13 (45% of these QTLs were derived from O. nivara, and enhancing alleles at all the QTLs for stem diameter and rachis diameter were derived from O. nivara. Three stem diameter QTLs, two rachis diameter QTLs and one number of secondary branches QTL identified by both Interval and composite interval mapping contributed more than 15% of the total phenotypic variance. The QTL epistasis was significant for stem diameter and plot yield. The most significant QTLs qSD7.2, qSD8.1 and qSD9.1 for stem diameter, qRD9.1 for rachis diameter and qNSB1.1 for number of secondary branches are good targets to evaluate their use in marker-assisted selection. O. nivara is a good source of novel alleles for yield related traits and reveals major effect QTLs suitable for marker-assisted selection.

  3. A donor-specific QTL, exhibiting allelic variation for leaf sheath hairiness in a nested association mapping population, is located on barley chromosome 4H

    KAUST Repository

    Saade, Stephanie

    2017-12-07

    Leaf sheath hairiness is a morphological trait associated with various advantages, including tolerance to both abiotic and biotic stresses, thereby increasing yield. Understanding the genetic basis of this trait in barley can therefore improve the agronomic performance of this economically important crop. We scored leaf sheath hairiness in a two-year field trial in 1,420 BC1S3 lines from the wild barley nested association mapping (NAM) population HEB-25. Leaf sheath hairiness segregated in six out of 25 families with the reference parent Barke being glabrous. We detected the major hairy leaf sheath locus Hs (syn. Hsh) on chromosome 4H (111.3 cM) with high precision. The effects of the locus varied across the six different wild barley donors, with donor of HEB family 11 conferring the highest score of leaf sheath hairiness. Due to the high mapping resolution present in HEB-25, we were able to discuss physically linked pentatricopeptide repeat genes and subtilisin-like proteases as potential candidate genes underlying this locus. In this study, we proved that HEB-25 provides an appropriate tool to further understand the genetic control of leaf sheath hairiness in barley. Furthermore, our work represents a perfect starting position to clone the gene responsible for the 4H locus observed.

  4. A donor-specific QTL, exhibiting allelic variation for leaf sheath hairiness in a nested association mapping population, is located on barley chromosome 4H.

    Directory of Open Access Journals (Sweden)

    Stephanie Saade

    Full Text Available Leaf sheath hairiness is a morphological trait associated with various advantages, including tolerance to both abiotic and biotic stresses, thereby increasing yield. Understanding the genetic basis of this trait in barley can therefore improve the agronomic performance of this economically important crop. We scored leaf sheath hairiness in a two-year field trial in 1,420 BC1S3 lines from the wild barley nested association mapping (NAM population HEB-25. Leaf sheath hairiness segregated in six out of 25 families with the reference parent Barke being glabrous. We detected the major hairy leaf sheath locus Hs (syn. Hsh on chromosome 4H (111.3 cM with high precision. The effects of the locus varied across the six different wild barley donors, with donor of HEB family 11 conferring the highest score of leaf sheath hairiness. Due to the high mapping resolution present in HEB-25, we were able to discuss physically linked pentatricopeptide repeat genes and subtilisin-like proteases as potential candidate genes underlying this locus. In this study, we proved that HEB-25 provides an appropriate tool to further understand the genetic control of leaf sheath hairiness in barley. Furthermore, our work represents a perfect starting position to clone the gene responsible for the 4H locus observed.

  5. Physiological factors affecting intrinsic water use efficiency of potato clones within a dihaploid mapping population under well-watered and drought-stressed conditions

    DEFF Research Database (Denmark)

    Topbjerg, Henrik Bak; Kaminski, Kacper Piotr; Markussen, Bo

    2014-01-01

    Optimizing crops water use is essential for ensuring food production under future climate scenarios. Therefore, new cultivars that are capable of maintaining production under limited water resource are needed. This study screened for clonal differences in intrinsic water use efficiency (WUEi......) within a dihaploid potato (Solanum tuberosum L.) mapping population under well-watered (WW) and drought-stress (DS) conditions. The factorial dependency of WUEi on several plant bio-physiological traits was analyzed, and clonal difference of WUEi was compared. Significant differences in WUEi were found...... with high WUEi could be potentially used as material in future breeding programs. Furthermore CCI seemed to be a reliable tool in estimating the clonal An and thereby WUEi....

  6. Evaluation of the capacity for direct regeneration of maize inbreds of the Lancaster selection group

    Directory of Open Access Journals (Sweden)

    K. V. Derkach

    2013-11-01

    Full Text Available In connection with the necessity of bringing elite maize inbreds of the Lancaster germplasm group, which have potential for cultivation in Ukraine, into the system of genetic tranformation, the aim of this investigation is to identify the ability of maize inbreds of this group to regenerate by direct organogenesis and to determine the optimal mineral basis for their nutritional environment using segments of the node area of shoots. As explantats we used sterile 4-day old seedlings of 4 maize inbreds of Lancaster germplasm and model inbred Chi31 exotic germplasm. The seedlings were obtained by germination of sterile seeds in Petri dishes between two layers of moist sterile filter paper at a temperature of 27 ºC in dark conditions. A single 1 cmlong segment was cut from each from each seedling, running from 0.5 cmbefore the node to 0.5 cmafter the node. A cut was made in each segment of the node in order to create a wounded surface. Explantats were planted in a nutrient environment with mineral bases of MS or N6, modified by the addition of 10 mg/l silver nitrate, 100 mg/l casein hydrolyzate, 690 mg/l L-proline, 30 g/l sucrose, 1.0 mg/l 2,4-dychlorphenoksiacetic acid and 0,1 mg/l abscisic acid. Cultivation was carried out at 25–27 ºC in the light. Direct hemogenesis in this environment on the 14th day of cultivation in vitro reached 100% for each line. This meant that all researched lines of Lancaster germplasm and the model line showed a high capacity for direct regeneration through direct hemogenesis, which does not depend on the composition of the mineral content of their nutritional environment. Callus formation was observed in all genotypes on the 14th day of cultivation in vitro and the extent of its formation increased during the following month of cultivation. The callus formation was observed only at the site of the wounded surface. The calluses were transparent. Although green areas appeared in these calluses, they were

  7. Mapping socio-environmentally vulnerable populations access and exposure to ecosystem services at the U.S.-Mexico borderlands

    Science.gov (United States)

    Norman, Laura M.; Villarreal, Miguel L.; Lara-Valencia, Francisco; Yuan, Yongping; Nie, Wenming; Wilson, Sylvia; Amaya, Gladys; Sleeter, Rachel

    2012-01-01

    Socio-environmental vulnerable populations are often unrepresented in land-use planning yet have great potential for loss when exposed to changes in ecosystem services. Administrative boundaries, cultural differences, and language barriers increase the disassociation between land-use management and marginalized populations living in the U.S.–Mexico borderlands. This paper describes the development of a Modified Socio-Environmental Vulnerability Index (M-SEVI), using determinants from binational census and neighborhood data that describe levels of education, access to resources, migratory status, housing, and number of dependents, to provide a simplified snapshot of the region's populace that can be used in binational planning efforts. We apply this index at the SCW, located on the border between Arizona, USA and Sonora, Mexico. For comparison, the Soil and Water Assessment Tool is concurrently applied to assess the provision of erosion- and flood control services over a 9-year period. We describe how this coupling of data can form the base for an ecosystem services assessment across political boundaries that can be used by land-use planners. Results reveal potential disparities in environmental risks and burdens throughout the binational watershed in residential districts surrounding and between urban centers. The M-SEVI can be used as an important first step in addressing environmental justice for binational decision-making.

  8. Dissection of Recombination Attributes for Multiple Maize Populations Using a Common SNP Assay

    Directory of Open Access Journals (Sweden)

    Haiying Guan

    2017-11-01

    Full Text Available Recombination is a vital characteristic for quantitative trait loci mapping and breeding to enhance the yield potential of maize. However, recombination characteristics in globally used segregating populations have never been evaluated at similar genetic marker densities. This study aimed to divulge the characteristics of recombination events, recombinant chromosomal segments, and recombination frequency for four dissimilar populations. These populations were doubled haploid (DH, recombination inbred line (RIL, intermated B73xMo17 (IBM, and multi-parent advanced generation inter-cross (MAGIC, using the Illumina MaizeSNP50 BeadChip to provide markers. Our results revealed that the average number of recombination events was 16, 41, 72, and 86 per line in DH, RIL, IBM, and MAGIC populations, respectively. Accordingly, the average length of recombinant chromosomal segments was 84.8, 47.3, 29.2, and 20.4 Mb in DH, RIL, IBM, and MAGIC populations, respectively. Furtherly, the recombination frequency varied in different genomic regions and population types [DH (0–12.7 cM/Mb, RIL (0–15.5 cM/Mb, IBM (0–24.1 cM/Mb, MAGIC (0–42.3 cM/Mb]. Utilizing different sub-sets of lines, the recombination bin number and size were analyzed in each population. Additionally, different sub-sets of markers and lines were employed to estimate the recombination bin number and size via formulas for relationship in these populations. The relationship between recombination events and recombination bin length was also examined. Our results contribute to determining the most suitable number of genetic markers, lines in each population, and population type for successful mapping and breeding.

  9. Whole genome re-sequencing reveals genome-wide variations among parental lines of 16 mapping populations in chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Thudi, Mahendar; Khan, Aamir W; Kumar, Vinay; Gaur, Pooran M; Katta, Krishnamohan; Garg, Vanika; Roorkiwal, Manish; Samineni, Srinivasan; Varshney, Rajeev K

    2016-01-27

    Chickpea (Cicer arietinum L.) is the second most important grain legume cultivated by resource poor farmers in South Asia and Sub-Saharan Africa. In order to harness the untapped genetic potential available for chickpea improvement, we re-sequenced 35 chickpea genotypes representing parental lines of 16 mapping populations segregating for abiotic (drought, heat, salinity), biotic stresses (Fusarium wilt, Ascochyta blight, Botrytis grey mould, Helicoverpa armigera) and nutritionally important (protein content) traits using whole genome re-sequencing approach. A total of 192.19 Gb data, generated on 35 genotypes of chickpea, comprising 973.13 million reads, with an average sequencing depth of ~10 X for each line. On an average 92.18 % reads from each genotype were aligned to the chickpea reference genome with 82.17 % coverage. A total of 2,058,566 unique single nucleotide polymorphisms (SNPs) and 292,588 Indels were detected while comparing with the reference chickpea genome. Highest number of SNPs were identified on the Ca4 pseudomolecule. In addition, copy number variations (CNVs) such as gene deletions and duplications were identified across the chickpea parental genotypes, which were minimum in PI 489777 (1 gene deletion) and maximum in JG 74 (1,497). A total of 164,856 line specific variations (144,888 SNPs and 19,968 Indels) with the highest percentage were identified in coding regions in ICC 1496 (21 %) followed by ICCV 97105 (12 %). Of 539 miscellaneous variations, 339, 138 and 62 were inter-chromosomal variations (CTX), intra-chromosomal variations (ITX) and inversions (INV) respectively. Genome-wide SNPs, Indels, CNVs, PAVs, and miscellaneous variations identified in different mapping populations are a valuable resource in genetic research and helpful in locating genes/genomic segments responsible for economically important traits. Further, the genome-wide variations identified in the present study can be used for developing high density SNP arrays for

  10. Quantitative Trait Loci Mapping of Western Corn Rootworm (Coleoptera: Chrysomelidae) Host Plant Resistance in Two Populations of Doubled Haploid Lines in Maize (Zea mays L.).

    Science.gov (United States)

    Bohn, Martin O; Marroquin, Juan J; Flint-Garcia, Sherry; Dashiell, Kenton; Willmot, David B; Hibbard, Bruce E

    2018-02-09

    Over the last 70 yr, more than 12,000 maize accessions have been screened for their level of resistance to western corn rootworm, Diabrotica virgifera virgifera (LeConte; Coleoptera: Chrysomelidae), larval feeding. Less than 1% of this germplasm was selected for initiating recurrent selection or other breeding programs. Selected genotypes were mostly characterized by large root systems and superior root regrowth after root damage caused by western corn rootworm larvae. However, no hybrids claiming native (i.e., host plant) resistance to western corn rootworm larval feeding are currently commercially available. We investigated the genetic basis of western corn rootworm resistance in maize materials with improved levels of resistance using linkage disequilibrium mapping approaches. Two populations of topcrossed doubled haploid maize lines (DHLs) derived from crosses between resistant and susceptible maize lines were evaluated for their level of resistance in three to four different environments. For each DHL topcross an average root damage score was estimated and used for quantitative trait loci (QTL) analysis. We found genomic regions contributing to western corn rootworm resistance on all maize chromosomes, except for chromosome 4. Models fitting all QTL simultaneously explained about 30 to 50% of the genotypic variance for root damage scores in both mapping populations. Our findings confirm the complex genetic structure of host plant resistance against western corn rootworm larval feeding in maize. Interestingly, three of these QTL regions also carry genes involved in ascorbate biosynthesis, a key compound we hypothesize is involved in the expression of western corn rootworm resistance. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Sequence-Based Introgression Mapping Identifies Candidate White Mold Tolerance Genes in Common Bean

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    Sujan Mamidi

    2016-07-01

    Full Text Available White mold, caused by the necrotrophic fungus (Lib. de Bary, is a major disease of common bean ( L.. WM7.1 and WM8.3 are two quantitative trait loci (QTL with major effects on tolerance to the pathogen. Advanced backcross populations segregating individually for either of the two QTL, and a recombinant inbred (RI population segregating for both QTL were used to fine map and confirm the genetic location of the QTL. The QTL intervals were physically mapped using the reference common bean genome sequence, and the physical intervals for each QTL were further confirmed by sequence-based introgression mapping. Using whole-genome sequence data from susceptible and tolerant DNA pools, introgressed regions were identified as those with significantly higher numbers of single-nucleotide polymorphisms (SNPs relative to the whole genome. By combining the QTL and SNP data, WM7.1 was located to a 660-kb region that contained 41 gene models on the proximal end of chromosome Pv07, while the WM8.3 introgression was narrowed to a 1.36-Mb region containing 70 gene models. The most polymorphic candidate gene in the WM7.1 region encodes a BEACH-domain protein associated with apoptosis. Within the WM8.3 interval, a receptor-like protein with the potential to recognize pathogen effectors was the most polymorphic gene. The use of gene and sequence-based mapping identified two candidate genes whose putative functions are consistent with the current model of pathogenicity.

  12. A consensus genetic map for Pinus taeda and Pinus elliottii and extent of linkage disequilibrium in two genotype-phenotype discovery populations of Pinua taeda

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    Jared W. Westbrook; Vikram E. Chhatre; Le-Shin Wu; Srikar Chamala; Leandro Gomide Neves; Patricio Munoz; Pedro J. Martinez-Garcia; David B. Neale; Matias Kirst; Keithanne Mockaitis; C. Dana Nelson; Gary F. Peter; John M. Davis; Craig S. Echt

    2015-01-01

    A consensus genetic map for Pinus taeda (loblolly pine) and Pinus elliottii (slash pine) was constructed by merging three previously published P. taeda maps with a map from a pseudo-backcross between P. elliottii and P. taeda. The consensus map positioned 3856 markers via...

  13. Combining abilities of maize inbred lines for grain yield and yield components

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    Živanović Tomislav

    2010-01-01

    Full Text Available Diallel mating design experiment with reciprocal crosses was used to determine combining abilities of five maize inbred lines and their hybrid combinations for grain yield, ear length, ear diameter, number of kernel rows per ear, number of kernels per row in 2005. and 2006. year. GCA and SCA significant values were observed for all traits under study in both years. GCA/SCA relation showed that dominant gene effect had prevalent influence in the inheritance of grain yield, ear length and ear diameter. Additive gene effect had larger importance in the inheritance of number of kernel rows per ear. NS-1445 inbred line showed best GCA effect for grain yield, ear length and number of kernels per row, but worst GCA effect for number of kernel rows per ear. Best GCA effect for ear diameter achieved inbred line F-7R. Line BL-47 showed best GCA effect for number of kernel rows per ear in both years, but also the worst GCA effect for grain yield and number of kernels per row. Hybrid combination NS-1445 x BL-47 showed largest SCA effect for grain yield in both years and also showed, like hybrid combination F-7R x NS-1445, significant SCA effects for all other traits, except ear diameter. This cross also proved that hybrid combinations that include one parent with good GCA effect and the other parent with bad GCA effect can have very successful performance. It will be useful during selection material testing, to keep also genotypes which show bad GCA effect, but have phenotypic favorable trait values. Reciprocity effect was significant for SCA effects of all traits but ear diameter. It is the conformation of involvement of plasmagenes in maize quantitative traits inheritance. The largest reciprocity effect for grain yield achieved F-7R x BL-47 in both years. Significantly higher grain yield in this hybrid combination was achieved when line F-7R was used as a female parent and significantly higher number of kernel rows per ear was achieved when line BL-47 was

  14. Evaluation of ear rot (Fusarium verticillioides resistance and fumonisin accumulation in Italian maize inbred lines

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    Carlotta BALCONI

    2014-05-01

    Full Text Available Mycotoxin contamination of maize (Zea mays L. grain is a global threat to the safety of both human food and animal feed. Hence, the development of maize genotypes with reduced mycotoxin accumulation in grain is of major importance. In order to find maize germplasm sources of resistance to Fusarium ear rot, 34 Italian and six public inbred lines were evaluated by means of artificial inoculation in field experiments during 2009 and 2010. Relationships between ear rot and fumonisin concentration in the ears were investigated. Primary ears were challenged with a mixture of two Fusarium verticillioides isolates from Northern Italy, through kernel inoculation, and ear rot severity was assessed.The average number of visibly infected kernels per ear, after inoculation, ranged from 2 to 68 in 2009 and from 0 to 120 in 2010. Fumonisin concentrations in the inoculated ears were greater than in the experimental controls for both years. Variability was found between the inbred lines: fumonisin accumulation ranged from 0.56 to 240.83 mg kg-1 in 2009 and from 1.09 to 190.60 mg kg-1 in 2010. In both years, six inbred lines showed high fumonisin content (≥100 mg kg-1, while the other genotypes were almost equally split into two groups, low (≤10 mg kg-1 and medium (from 11 to 100 mg kg-1 fumonisin content. The number of infected kernels after artificial inoculation correlated with fumonisin concentration both in 2009 (r = 0.94; P≤0.01 and 2010 (r = 0.67; P≤0.01. Additionally, the percentage of internally infected kernels correlated positively with fumonisin concentration (r = 0.37; P≤0.01 and with the number of infected kernels (r = 0.29; P≤0.05. This research has demonstrated that Italian maize germplasm is a valid source of resistance to Fusarium ear rot. Furthermore, there is a strong association of visible Fusarium symptoms with fumonisin concentration, suggesting that selection in maize for reduced visible moulds should reduce the risk of

  15. In-silico QTL mapping of postpubertal mammary ductal development in the mouse uncovers potential human breast cancer risk loci

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    Genetic background plays a dominant role in mammary gland development and breast cancer (BrCa). Despite this, the role of genetics is only partially understood. This study used strain-dependent variation in an inbred mouse mapping panel, to identify quantitative trait loci (QTL) underlying structura...

  16. Anopheles darlingi polytene chromosomes: revised maps including newly described inversions and evidence for population structure in Manaus.

    Science.gov (United States)

    Cornel, Anthony J; Brisco, Katherine K; Tadei, Wanderli P; Secundino, Nágila Fc; Rafael, Miriam S; Galardo, Allan Kr; Medeiros, Jansen F; Pessoa, Felipe Ac; Ríos-Velásquez, Claudia M; Lee, Yoosook; Pimenta, Paulo Fp; Lanzaro, Gregory C

    2016-05-01

    Salivary gland polytene chromosomes of 4th instar Anopheles darlingi Root were examined from multiple locations in the Brazilian Amazon. Minor modifications were made to existing polytene photomaps. These included changes to the breakpoint positions of several previously described paracentric inversions and descriptions of four new paracentric inversions, two on the right arm of chromosome 3 and two on the left arm of chromosome 3 that were found in multiple locations. A total of 18 inversions on the X (n = 1) chromosome, chromosome 2 (n = 7) and 3 (n = 11) were scored for 83 individuals from Manaus, Macapá and Porto Velho municipalities. The frequency of 2Ra inversion karyotypes in Manaus shows significant deficiency of heterozygotes (p < 0.0009). No significant linkage disequilibrium was found between inversions on chromosome 2 and 3. We hypothesize that at least two sympatric subpopulations exist within the An. darlingi population at Manaus based on inversion frequencies.

  17. Differential equilibration and intergranular diffusion of trace elements during rapid regional metamorphism: constraints from LA-ICP-MS mapping of a garnet population

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    George, F. R.; Gaidies, F.

    2017-12-01

    Trace element zoning contained within a metapelitic garnet population yields information pertaining to a more complex prograde reaction history than is evident in major element zoning patterns and other conventional analyses. In particular, while trace elements may not act as a rate-limiting component for garnet crystallization, their incorporation into garnet growth surfaces provides a nuanced insight into the crystallization history of the population, and the extent of equilibration of trace elements in the matrix. In this study, we present LA-ICP-MS raster maps of trace element concentrations from several population-representative, centrally sectioned garnets from a garnet-grade metapelite of the Sikkim Himalaya, India. Equilibrium forward modeling of garnet crystallization and simulation of diffusional modification indicates that the garnet population crystallized rapidly over <1 Myr between 515 °C/4.5 kbar and 565 °C/5.5 kbar, as a consequence of high heating rates during regional amphibolite-facies metamorphism. While the rate of diffusional homogenization of major divalent cations is interpreted to have exceeded the rate of interfacial advance (yielding simple prograde growth zoning), trace element distributions record a more complex transport history. In particular, yttrium and the heavy rare earth elements (HREE) document a transition from an overprinted sigmoidal core to concentric repeated HREE and yttrium annuli in all crystals. This suggests that there was a discrete increase in the length scale of equilibration along the advancing garnet interface at some point in the growth history. However, there is no evidence for a coeval change in HREE transport thorough the intergranular network. Conversely, spiral core-to-rim zoning of chromium indicates the element remains almost completely immobile in the matrix over the duration of garnet growth.

  18. Using remote sensing to map larval and adult populations of Anopheles hyrcanus (Diptera: Culicidae a potential malaria vector in Southern France

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    Roger François

    2008-02-01

    Full Text Available Abstract Background Although malaria disappeared from southern France more than 60 years ago, suspicions of recent autochthonous transmission in the French Mediterranean coast support the idea that the area could still be subject to malaria transmission. The main potential vector of malaria in the Camargue area, the largest river delta in southern France, is the mosquito Anopheles hyrcanus (Diptera: Culicidae. In the context of recent climatic and landscape changes, the evaluation of the risk of emergence or re-emergence of such a major disease is of great importance in Europe. When assessing the risk of emergence of vector-borne diseases, it is crucial to be able to characterize the arthropod vector's spatial distribution. Given that remote sensing techniques can describe some of the environmental parameters which drive this distribution, satellite imagery or aerial photographs could be used for vector mapping. Results In this study, we propose a method to map larval and adult populations of An. hyrcanus based on environmental indices derived from high spatial resolution imagery. The analysis of the link between entomological field data on An. hyrcanus larvae and environmental indices (biotopes, distance to the nearest main productive breeding sites of this species i.e., rice fields led to the definition of a larval index, defined as the probability of observing An. hyrcanus larvae in a given site at least once over a year. Independent accuracy assessments showed a good agreement between observed and predicted values (sensitivity and specificity of the logistic regression model being 0.76 and 0.78, respectively. An adult index was derived from the larval index by averaging the larval index within a buffer around the trap location. This index was highly correlated with observed adult abundance values (Pearson r = 0.97, p An. hyrcanus larval and adult populations from the landscape indices. Conclusion This work shows that it is possible to use

  19. Fine-mapping the MHC region in Asian populations identified novel variants modifying susceptibility to lung cancer.

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    Qin, Na; Wang, Cheng; Zhu, Meng; Lu, Qun; Ma, Zijian; Huang, Mingtao; Dai, Juncheng; Ma, Hongxia; Jin, Guangfu; Hu, Zhibin; Shen, Hongbing

    2017-10-01

    The polymorphic major histocompatibility complex (MHC) plays a vital role in the immune system and drives predisposition to multiple cancers. A number of lung cancer-related genetic variants in the MHC have been identified in recent genome-wide association studies; however, the causal variants remain unclear. In the present study, we conducted a large-scale fine-mapping study of lung cancer in the MHC region of 13,945 unrelated Asian individuals to search for potential causal variants. We used the recently constructed Pan-Asian panel as the reference and imputed eight HLA genes (HLA-A, HLC-B, HLA-C, HLA-DRB1, HLA-DQA1, HLA-DQB1, HLA-DPA1, and HLA-DPB1) using SNP2HLA software. We identified one single nucleotide polymorphism, rs12333226 (OR=1.41, P=3.97×10 -7 ), five HLA amino acid polymorphisms in HLA-DRB1 (OR=0.89, P=7.51×10 -6 -8.57×10 -6 ), and one two-digit classic HLA allele HLA-A*11 (OR=0.87, P=9.68×10 -6 ) that were strongly associated with the risk of lung cancer. Rs12333226 was an expression quantitative trait locus of HLA-A and HLA-H in circulating monocytes, and exerted effect on lung cancer risk especially in the younger. HLA-DRβ1 positions 10, 16, and 25 drove the effect of one reported SNP rs2395185. The peptide position analysis identified additional lung cancer susceptibility amino acid positions, including HLA-DRβ1 position 30 and 11 (P omnibus =6.11×10 -5 and 6.91×10 -5 ), HLA-DQa1 47 and 76 (P omnibus =3.96×10 -4 and 1.41×10 -2 ) and HLA-A 152 (P omnibus =4.86×10 -4 ). Most of the peptide positions were located in the peptide-binding grooves and seemed to affect antigen presentation. All the existing and novel variants explained approximately 2.37% of the phenotypic variances, while 21.10% was attributed to the variants identified in this study. We identified seven novel bi-allelic variants and five polymorphic amino acid positions in HLA-DRβ1, HLA-DQα1, and HLA-A that confer a risk of lung cancer. This finding provides evidence for

  20. Agrobacterium-mediated high-frequency transformation of an elite commercial maize (Zea mays L.) inbred line.

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    Cho, Myeong-Je; Wu, Emily; Kwan, Jackie; Yu, Maryanne; Banh, Jenny; Linn, Wutt; Anand, Ajith; Li, Zhi; TeRonde, Susan; Register, James C; Jones, Todd J; Zhao, Zuo-Yu

    2014-10-01

    An improved Agrobacterium -mediated transformation protocol is described for a recalcitrant commercial maize elite inbred with optimized media modifications and AGL1. These improvements can be applied to other commercial inbreds. This study describes a significantly improved Agrobacterium-mediated transformation protocol in a recalcitrant commercial maize elite inbred, PHR03, using optimal co-cultivation, resting and selection media. The use of green regenerative tissue medium components, high copper and 6-benzylaminopurine, in resting and selection media dramatically increased the transformation frequency. The use of glucose in resting medium further increased transformation frequency by improving the tissue induction rate, tissue survival and tissue proliferation from immature embryos. Consequently, an optimal combination of glucose, copper and cytokinin in the co-cultivation, resting and selection media resulted in significant improvement from 2.6 % up to tenfold at the T0 plant level using Agrobacterium strain LBA4404 in transformation of PHR03. Furthermore, we evaluated four different Agrobacterium strains, LBA4404, AGL1, EHA105, and GV3101 for transformation frequency and event quality. AGL1 had the highest transformation frequency with up to 57.1 % at the T0 plant level. However, AGL1 resulted in lower quality events (defined as single copy for transgenes without Agrobacterium T-DNA backbone) when compared to LBA4404 (30.1 vs 25.6 %). We propose that these improvements can be applied to other recalcitrant commercial maize inbreds.

  1. Carotenoid accumulation and carotenogenic gene expression during fruit development in novel interspecific inbred squash lines and their parents.

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    Nakkanong, Korakot; Yang, Jing Hua; Zhang, Ming Fang

    2012-06-13

    Carotenoid levels and composition during squash fruit development were compared in Cucurbita moschata , Cucurbita maxima , and two lines of their interspecific inbred lines, namely, Maxchata1 and Maxchata2. Eight genes associated with carotenoid biosynthesis were analyzed by quantitative RT-PCR. The two squash species and their interspecific inbred lines exhibited different qualitative and quantitative carotenoid profiles and regulatory mechanisms. C. moschata had the lowest total carotenoid content and mainly accumulated α-carotene and β-carotene, as expected in a fruit with pale-orange flesh. Low carotenoid content in this species was probably due to the comparatively low expression of all genes investigated, especially PSY1 gene, compared to the other squashes. The predominant carotenoids in C. maxima were violaxanthin and lutein, which produced a corresponding yellow flesh color in mature fruit. The relationship between the expression of the CHYB and ZEP genes may result in almost equal concentrations of violaxanthin and lutein in C. maxima at fruit ripening. In contrast, their interspecific inbred lines principally accumulated lutein and β-carotene, leading to orange flesh color. The PSY1 gene exhibited higher expression levels at earlier stages of fruit development in the Maxchata lines, potentially triggering the increased carotenoid accumulation seen in these fruits. Likewise, the higher transcription level of CHYB gene observed in the two interspecific inbred lines might be correlated with high lutein in these hybrids. However, this study could not explain the observed β-carotene accumulation on the basis of gene expression.

  2. Worm burdens in outbred and inbred laboratory rats with morphometric data on Syphacia muris (Yamaguti, 1935 Yamaguti, 1941 (Nematoda, Oxyuroidea

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    Roberto Magalhães Pinto

    2001-01-01

    Full Text Available Syphacia muris worm burdens were evaluated in the rat Rattus norvegicus of the strains Wistar (outbred, Low/M and AM/2/Torr (inbred, maintained conventionally in institutional animal houses in Brazil. Morphometrics and illustration data for S. muris recovered from Brazilian laboratory rats are provided for the first time since its proposition in 1935.

  3. Draft assembly of elite inbred line PH207 provides insights into genomic and transcriptome diversity in maize

    Science.gov (United States)

    Intense artificial selection over the last 100 years has produced elite maize (Zea mays) inbred lines that combine to produce high-yielding hybrids. To further our understanding of how genome and transcriptome variation contribute to the production of high-yielding hybrids, we generated a draft geno...

  4. Potencial de híbridos simples de milho para extração de linhagens Potential of maize single hybrids to generate inbred lines

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    Odair Bison

    2003-04-01

    Full Text Available A utilização de híbridos simples comerciais de milho é uma das opções de populações para a extração de linhagens, porque são adaptados e provavelmente concentram alta freqüência de alelos favoráveis já fixados. Mesmo nos locos que estão segregando, a freqüência de alelos favoráveis é 0,5. Assim, a identificação de populações promissoras, derivadas de híbridos simples superiores, é uma boa estratégia para aumentar a eficiência dos programas de melhoramento. As populações derivadas dos híbridos simples comerciais AG9012 e C333 foram avaliadas com o objetivo de verificar o potencial dessas para extração de linhagens superiores, por meio das estimativas de parâmetros genéticos e fenotípicos, da estimativa de m+a e a metodologia proposta por Jinks & Pooni (1976. Foram avaliadas 169 famílias S1 de cada população, durante a safra agrícola de 1999/2000, na área experimental do Departamento de Biologia da UFLA, em Lavras - MG, em látice simples 13x13, sendo as parcelas constituídas por uma linha de 3 m. As características analisadas foram incidência de Phaeosphaeria maydis em duas épocas, altura de plantas, altura de espigas e produtividade de espigas despalhadas. Foi constatado que há possibilidade de se obterem linhagens com bom desempenho per se, sendo a população derivada do C333 a mais promissora, por associar resistência a Phaeosphaeria maydis e possuir média mais alta e maior probabilidade de obtenção de linhagens superiores. A metodologia proposta por Jinks & Pooni (1976 mostrou-se mais informativa do que a estimativa de m+a para a escolha de populações, mas, quando possível, as duas podem ser utilizadas simultaneamente para auxiliar na decisão dos melhoristas.Populations derived from commercial single hybrids are one of the breeder options for inbred line extraction because of their adaptation and probable high frequency of loci with fixed favorable alleles. Even the segregating loci carry

  5. Sunflower inbred lines screening for tolerance to white rot on stalk

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    Dedić Boško

    2011-01-01

    Full Text Available Seventy sunflower (Helianthus annuus L inbred lines were screened for tolerance to white rot on stalk. Plants were inoculated at the budding stage with 4-day old Sclerotinia mycelium grown on PDA medium. Mycelium was placed on the leaf top and covered with tin foil, and the leaf was put into transparent nylon bag in order to maintain high humidity. Spot length on leaf was measured and plant tolerance was determined at the full flowering stage. Obtained results were analyzed by analysis of variance. Tested lines showed significant variability in response to disease. Eleven lines had lesion length less than 50% compared to susceptible control, so they could be considered tolerant and potentially interesting for breeding program.

  6. Diallel analysis of maize inbred lines for grain yield, oil and protein content

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    Amir José Klein Werle

    2014-03-01

    Full Text Available This study aimed to investigate the combining ability and heterotic effects on grain yield (GY, oil content (OC and crude protein (CP in tropical and temperate maize lines. Hybrids and inbred lines were evaluated in a complete diallel scheme without reciprocals, in two experiments in randomized blocks with three replications. The partitioning of the sum of squares for general (GCA and specific (SCA combining ability indicated that both additive and non-additive effects were involved in the genetic control of the studied traits. The estimates of the quadratic components showed predominance of non-additive genetic effects in the trait control. However, for OC and CP, the non-additive effect had a clearly negative influenc

  7. Nocardia infections in congenitally athymic (nude) mice and in other inbred mouse strains.

    Science.gov (United States)

    Folb, P I; Timme, A; Horowitz, A

    1977-01-01

    The mortality rate and histopathological features of Nocardia asteroides and Nocardia brasiliensis infections in congenitally athymic (nude) mice of ICR and C3H/eB origins were quite different from what we found for Swiss white mice and other inbred mouse strains (namely, C57/BL/6J, New Zealand Black, BALB/c, CBA/LAC, and C3H/eB). The immunocompetent littermates of the congenitally athymic mice occupied an intermediate position between their athymic siblings and Swiss white mice in terms of their responses to both these organisms. Macrophage ingestion and destruction of N. brasiliensis, as demonstrated by electron microscopy, was found to occur. The T-lymphocyte appears to be an essential component in normal mouse resistance to infection by both N. asteroides and N. brasiliensis. Images PMID:336547

  8. Comparison of statistical methods for genetic similarity evaluation of maize inbred lines

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    Nikolić Ana

    2017-01-01

    Full Text Available Conventional breeding methods have been aided by molecular genetic techniques giving the chance for efficient improvement in creation of maize hybrids. Proper choice of statistical methods for data analysis is very important because it ensures greater reliability. The aim of this study was to determine the most suitable statistical approach for molecular marker data analysis. SSR markers were used for the analysis of 10 maize inbreds. Genetic similarity/distance was calculated using three types of data: binary, allele frequency based on densitometry and allele frequency according to band size data applying Simple matching, Jaccard's and Rogers' coefficient. Cluster analysis was performed in NTSYS, 2.11a software. The highest value for Spearman's rank of correlation (0.95 was detected between distance matrices based on binary data. The results showed that binary data Jaccard's coefficient and allele frequency data based on fragment sizes (Rogers' coefficient gave identical clusters by visual inspection and according to CIc index.

  9. [Anatomy of heart in banna mini-pig inbred-lines].

    Science.gov (United States)

    Zhang, Wei; Ying, Da-jun; Sun, Jian-sen

    2003-01-01

    To observe the heart anatomic and histological structure of the Banna mini-pig inbred-lined and to provide the morphological data for heart xenotransplantation and breeding transgens pig. Ten Banna mini-pigs (12-18 months old) were affused and fixed by common coratid artery. The heart were observed and measured by gross anatomy and histology. There were many similarities between the Banna pig heart and the human heart in anatomy and histology. However, the following differences were observed in the Banna pig heart: 1. Azygos vein directly drew into right atrium cordis. 2. The intercalated disk of cardiac muscle was less than that of human. 3. The Purkinje's fibre was bigger than that of human. On the morphology and histology, the structure of Banna pig heart is similar to the heart of human being. It is possible that Banna minipig heart becomes organ donors for xenotransplantation.

  10. Correlation between DNA repair of embryonic fibroblasts and different life span of 3 inbred mouse strains

    Energy Technology Data Exchange (ETDEWEB)

    Paffenholz, V.

    1978-02-01

    Primary mouse fibroblast cultures were established from 10 day old embryos of 3 inbred strains with a genetically determined different life expectancy. The capacity for unscheduled DNA synthesis following uv irradiation was studied in these cells at various passage levels of the in vitro ageing process. The mouse fibroblasts show considerable repair synthesis corresponding to the duration of exposure time. The capacity for induction of unscheduled DNA synthesis was different in the cells of each strain and correlated to the natural life span of the animal. In each case, however, the ability to perform repair synthesis was subjected to an age-associated decline, although semiconservative DNA synthesis and proliferative potential of the cell was not changed until the cultures entered phase III passages.

  11. Variation in anti-predator behavior among five strains of inbred guppies, Poecilia reticulata.

    Science.gov (United States)

    Bleakley, Bronwyn H; Martell, Christopher M; Brodie, Edmund D

    2006-09-01

    Quantitative genetic studies frequently utilize inbred strains of animals as tools for partitioning the direct and indirect effects of genes from environmental effects in generating an observed phenotype, however, this approach is rarely applied to behavioral studies. Guppies, Poecilia reticulata, perform a set of anti-predator behaviors that may provide an ideal system to study how complex behavioral traits are generated. To assess the utility of ornamental guppies in quantitative genetics studies of behavior, we assayed five morphologically distinct strains of ornamental guppies for response to predator cues and for variation in response among strains. Despite individual variation, all five strains responded to predator cues and differences among strains were found for all assayed behaviors, including measures of boldness and predator avoidance.

  12. Mapping in an apple (Malus x domestica) F1 segregating population based on physical clustering of differentially expressed genes.

    Science.gov (United States)

    Jensen, Philip J; Fazio, Gennaro; Altman, Naomi; Praul, Craig; McNellis, Timothy W

    2014-04-04

    Apple tree breeding is slow and difficult due to long generation times, self-incompatibility, and complex genetics. The identification of molecular markers linked to traits of interest is a way to expedite the breeding process. In the present study, we aimed to identify genes whose steady-state transcript abundance was associated with inheritance of specific traits segregating in an apple (Malus × domestica) rootstock F1 breeding population, including resistance to powdery mildew (Podosphaera leucotricha) disease and woolly apple aphid (Eriosoma lanigerum). Transcription profiling was performed for 48 individual F1 apple trees from a cross of two highly heterozygous parents, using RNA isolated from healthy, actively-growing shoot tips and a custom apple DNA oligonucleotide microarray representing 26,000 unique transcripts. Genome-wide expression profiles were not clear indicators of powdery mildew or woolly apple aphid resistance phenotype. However, standard differential gene expression analysis between phenotypic groups of trees revealed relatively small sets of genes with trait-associated expression levels. For example, thirty genes were identified that were differentially expressed between trees resistant and susceptible to powdery mildew. Interestingly, the genes encoding twenty-four of these transcripts were physically clustered on chromosome 12. Similarly, seven genes were identified that were differentially expressed between trees resistant and susceptible to woolly apple aphid, and the genes encoding five of these transcripts were also clustered, this time on chromosome 17. In each case, the gene clusters were in the vicinity of previously identified major quantitative trait loci for the corresponding trait. Similar results were obtained for a series of molecular traits. Several of the differentially expressed genes were used to develop DNA polymorphism markers linked to powdery mildew disease and woolly apple aphid resistance. Gene expression profiling

  13. Comparison of inbred mouse substrains reveals segregation of maladaptive fear phenotypes

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    Stephanie J Temme

    2014-08-01

    Full Text Available Maladaptive fear, such as fear that is persistent or easily generalized to a nonthreatening stimuli, is associated with anxiety-related disorders in humans. In the laboratory, maladaptive fear can be modeled in rodents using Pavlovian fear conditioning. Recently, an inbred mouse strain known as 129S1/SvImJ, or 129S1 have been reported as exhibiting impairments in fear extinction and enhanced fear generalization. With a long-term goal of identifying segregating genetic markers of maladaptive fear, we used Pavlovian fear conditioning to characterize a closely related substrain designated as 129S6/SvEvTac, or 129S6. Here we report that, like 129S1 animals, 129S6 mice exhibit appropriate levels of fear upon conditioning, but are unable to extinguish fear memories once they are consolidated. Importantly, the maladaptive fear phenotype in this inbred stain can be segregated by sub-strain when probed using conditioning protocols designed to assess generalized fear. We find that unlike the 129S1 substrain, mice from the 129S6 sub-strain do not generalize conditioned fear to previously novel contexts and can learn to discriminate between two similar contexts when trained using a discrimination protocol. These results suggest that at least two forms of maladaptive fear (deficits in fear extinction and fear generalization can be can be functionally segregated, further suggesting that the underlying neurobiology is heritable. Given the observation that two closely related sub-strains can exhibit different constellations of maladaptive fear suggests that these findings could be exploited to facilitate the identification of candidate genes for anxiety-related disorders.

  14. Transcriptome Analyses of Mosaic (MSC Mitochondrial Mutants of Cucumber in a Highly Inbred Nuclear Background

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    Tomasz L. Mróz

    2018-03-01

    Full Text Available Cucumber (Cucumis sativus L. has a large, paternally transmitted mitochondrial genome. Cucumber plants regenerated from cell cultures occasionally show paternally transmitted mosaic (MSC phenotypes, characterized by slower growth, chlorotic patterns on the leaves and fruit, lower fertility, and rearrangements in their mitochondrial DNAs (mtDNAs. MSC lines 3, 12, and 16 originated from different cell cultures all established using the highly inbred, wild-type line B. These MSC lines possess different rearrangements and under-represented regions in their mtDNAs. We completed RNA-seq on normalized and non-normalized cDNA libraries from MSC3, MSC12, and MSC16 to study their nuclear gene-expression profiles relative to inbred B. Results from both libraries indicated that gene expression in MSC12 and MSC16 were more similar to each other than MSC3. Forty-one differentially expressed genes (DEGs were upregulated and one downregulated in the MSC lines relative to B. Gene functional classifications revealed that more than half of these DEGs are associated with stress-response pathways. Consistent with this observation, we detected elevated levels of hydrogen peroxide throughout leaf tissue in all MSC lines compared to wild-type line B. These results demonstrate that independently produced MSC lines with different mitochondrial polymorphisms show unique and shared nuclear responses. This study revealed genes associated with stress response that could become selection targets to develop cucumber cultivars with increased stress tolerance, and further support of cucumber as a model plant to study nuclear-mitochondrial interactions.

  15. Enriching an intraspecific genetic map and identifying QTL for fiber quality and yield component traits across multiple environments in Upland cotton (Gossypium hirsutum L.).

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    Liu, Xueying; Teng, Zhonghua; Wang, Jinxia; Wu, Tiantian; Zhang, Zhiqin; Deng, Xianping; Fang, Xiaomei; Tan, Zhaoyun; Ali, Iftikhar; Liu, Dexin; Zhang, Jian; Liu, Dajun; Liu, Fang; Zhang, Zhengsheng

    2017-12-01

    Cotton is a significant commercial crop that plays an indispensable role in many domains. Constructing high-density genetic maps and identifying stable quantitative trait locus (QTL) controlling agronomic traits are necessary prerequisites for marker-assisted selection (MAS). A total of 14,899 SSR primer pairs designed from the genome sequence of G. raimondii were screened for polymorphic markers between mapping parents CCRI 35 and Yumian 1, and 712 SSR markers showing polymorphism were used to genotype 180 lines from a (CCRI 35 × Yumian 1) recombinant inbred line (RIL) population. Genetic linkage analysis was conducted on 726 loci obtained from the 712 polymorphic SSR markers, along with 1379 SSR loci obtained in our previous study, and a high-density genetic map with 2051 loci was constructed, which spanned 3508.29 cM with an average distance of 1.71 cM between adjacent markers. Marker orders on the linkage map are highly consistent with the corresponding physical orders on a G. hirsutum genome sequence. Based on fiber quality and yield component trait data collected from six environments, 113 QTLs were identified through two analytical methods. Among these 113 QTLs, 50 were considered stable (detected in multiple environments or for which phenotypic variance explained by additive effect was greater than environment effect), and 18 of these 50 were identified with stability by both methods. These 18 QTLs, including eleven for fiber quality and seven for yield component traits, could be priorities for MAS.

  16. Neoplastic and nonneoplastic lesions in aging mice of unique and common inbred strains contribution to modeling of human neoplastic diseases.

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    Szymanska, H; Lechowska-Piskorowska, J; Krysiak, E; Strzalkowska, A; Unrug-Bielawska, K; Grygalewicz, B; Skurzak, H M; Pienkowska-Grela, B; Gajewska, M

    2014-05-01

    The evaluation of spontaneous lesions in classical inbred strains of mice has become increasingly important because genetically engineered mice (GEMs) are created on these backgrounds. Novel inbred strains-genetically diverse from classic strains-are valuable both as a new background for GEM mice and to increase the genetic variation found in laboratory mice. Newly arising spontaneous genetic alterations in commonly used strains may also lead to new and valuable mouse models of disease. This report evaluates gross and histological lesions in relatively new, classic, and rarely explored mouse inbred strains. Pathological lesions of 1273 mice from 12 inbred strains (129S1/SvW, A.CA-H2(f) /W, AKR/W, BALB/cW, BN/aW, C57BL/6 W, C57BL/10 W, C3H/W, C3H (wad) /W, CBA/W, DBA/2 W, and WOM/W) are reported. BN/aW, WOM/W, and C3H (wad) /W are novel inbred strains produced and maintained in the Department of Genetics and Laboratory Animal Breeding at the Center of Oncology, Warsaw, Poland. Both neoplastic and nonneoplastic lesions were examined. The prevalence of lung neoplasms was significantly higher in A.CA-H2(f) /W (33.3%) and BALB/cW (33.8%) mice (P WOM/W mice developed T-cell lymphoblastic lymphoma with high frequency (110/121 [90.9%] and 159/175 [90.9%], respectively) before 1 year of age. The occurrence of nonneoplastic lesions in the kidneys of BN/aW mice was increased (P < .01).

  17. Fine-mapping qFS07.1 controlling fiber strength in upland cotton (Gossypium hirsutum L.).

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    Fang, Xiaomei; Liu, Xueying; Wang, Xiaoqin; Wang, Wenwen; Liu, Dexin; Zhang, Jian; Liu, Dajun; Teng, Zhonghua; Tan, Zhaoyun; Liu, Fang; Zhang, Fengjiao; Jiang, Maochao; Jia, Xiuling; Zhong, Jianwei; Yang, Jinghong; Zhang, Zhengsheng

    2017-04-01

    KEY MESSAGE: qFS07.1 controlling fiber strength was fine-mapped to a 62.6-kb region containing four annotated genes. RT-qPCR and sequence of candidate genes identified an LRR RLK gene as the most likely candidate. Fiber strength is an important component of cotton fiber quality and is associated with other properties, such as fiber maturity, fineness, and length. Stable QTL qFS07.1, controlling fiber strength, had been identified on chromosome 7 in an upland cotton recombinant inbred line (RIL) population from a cross (CCRI35 × Yumian1) described in our previous studies. To fine-map qFS07.1, an F 2 population with 2484 individual plants from a cross between recombinant line RIL014 and CCRI35 was established. A total of 1518 SSR primer pairs, including 1062, designed from chromosome 1 of the Gossypium raimondii genome and 456 from chromosome 1 of the G. arboreum genome (corresponding to the QTL region) were used to fine-map qFS07.1, and qFS07.1 was mapped into a 62.6-kb genome region which contained four annotated genes on chromosome A07 of G. hirsutum. RT-qPCR and comparative analysis of candidate genes revealed a leucine-rich repeat protein kinase (LRR RLK) family protein to be a promising candidate gene for qFS07.1. Fine mapping and identification of the candidate gene for qFS07.1 will play a vital role in marker-assisted selection (MAS) and the study of mechanism of cotton fiber development.

  18. High Resolution Consensus Mapping of Quantitative Trait Loci for Fiber Strength, Length and Micronaire on Chromosome 25 of the Upland Cotton (Gossypium hirsutum L..

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    Zhen Zhang

    Full Text Available Cotton (Gossypium hirsutum L. is an important agricultural crop that provides renewable natural fiber resources for the global textile industry. Technological developments in the textile industry and improvements in human living standards have increased the requirement for supplies and better quality cotton. Upland cotton 0-153 is an elite cultivar harboring strong fiber strength genes. To conduct quantitative trait locus (QTL mapping for fiber quality in 0-153, we developed a population of 196 recombinant inbred lines (RILs from a cross between 0-153 and sGK9708. The fiber quality traits in 11 environments were measured and a genetic linkage map of chromosome 25 comprising 210 loci was constructed using this RIL population, mainly using simple sequence repeat markers and single nucleotide polymorphism markers. QTLs were identified across diverse environments using the composite interval mapping method. A total of 37 QTLs for fiber quality traits were identified on chromosome 25, of which 17 were stably expressed in at least in two environments. A stable fiber strength QTL, qFS-chr25-4, which was detected in seven environments and was located in the marker interval between CRI-SNP120491 and BNL2572, could explain 6.53%-11.83% of the observed phenotypic variations. Meta-analysis also confirmed the above QTLs with previous reports. Application of these QTLs could contribute to improving fiber quality and provide information for marker-assisted selection.

  19. High Resolution Consensus Mapping of Quantitative Trait Loci for Fiber Strength, Length and Micronaire on Chromosome 25 of the Upland Cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Zhang, Zhen; Li, Junwen; Muhammad, Jamshed; Cai, Juan; Jia, Fei; Shi, Yuzhen; Gong, Juwu; Shang, Haihong; Liu, Aiying; Chen, Tingting; Ge, Qun; Palanga, Koffi Kibalou; Lu, Quanwei; Deng, Xiaoying; Tan, Yunna; Li, Wei; Sun, Linyang; Gong, Wankui; Yuan, Youlu

    2015-01-01

    Cotton (Gossypium hirsutum L.) is an important agricultural crop that provides renewable natural fiber resources for the global textile industry. Technological developments in the textile industry and improvements in human living standards have increased the requirement for supplies and better quality cotton. Upland cotton 0-153 is an elite cultivar harboring strong fiber strength genes. To conduct quantitative trait locus (QTL) mapping for fiber quality in 0-153, we developed a population of 196 recombinant inbred lines (RILs) from a cross between 0-153 and sGK9708. The fiber quality traits in 11 environments were measured and a genetic linkage map of chromosome 25 comprising 210 loci was constructed using this RIL population, mainly using simple sequence repeat markers and single nucleotide polymorphism markers. QTLs were identified across diverse environments using the composite interval mapping method. A total of 37 QTLs for fiber quality traits were identified on chromosome 25, of which 17 were stably expressed in at least in two environments. A stable fiber strength QTL, qFS-chr25-4, which was detected in seven environments and was located in the marker interval between CRI-SNP120491 and BNL2572, could explain 6.53%-11.83% of the observed phenotypic variations. Meta-analysis also confirmed the above QTLs with previous reports. Application of these QTLs could contribute to improving fiber quality and provide information for marker-assisted selection.

  20. Multiple sex-associated regions and a putative sex chromosome in zebrafish revealed by RAD mapping and population genomics.

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    Jennifer L Anderson

    Full Text Available Within vertebrates, major sex determining genes can differ among taxa and even within species. In zebrafish (Danio rerio, neither heteromorphic sex chromosomes nor single sex determination genes of large effect, like Sry in mammals, have yet been identified. Furthermore, environmental factors can influence zebrafish sex determination. Although progress has been made in understanding zebrafish gonad differentiation (e.g. the influence of germ cells on gonad fate, the primary genetic basis of zebrafish sex determination remains poorly understood. To identify genetic loci associated with sex, we analyzed F(2 offspring of reciprocal crosses between Oregon *AB and Nadia (NA wild-type zebrafish stocks. Genome-wide linkage analysis, using more than 5,000 sequence-based polymorphic restriction site associated (RAD-tag markers and population genomic analysis of more than 30,000 single nucleotide polymorphisms in our *ABxNA crosses revealed a sex-associated locus on the end of the long arm of chr-4 for both cross families, and an additional locus in the middle of chr-3 in one cross family. Additional sequencing showed that two SNPs in dmrt1 previously suggested to be functional candidates for sex determination in a cross of ABxIndia wild-type zebrafish, are not associated with sex in our AB fish. Our data show that sex determination in zebrafish is polygenic and that different genes may influence sex determination in different strains or that different genes become more important under different environmental conditions. The association of the end of chr-4 with sex is remarkable because, unique in the karyotype, this chromosome arm shares features with known sex chromosomes: it is highly heterochromatic, repetitive, late replicating, and has reduced recombination. Our results reveal that chr-4 has functional and structural properties expected of a sex chromosome.

  1. Local genealogies in a linear mixed model for genome-wide association mapping in complex pedigreed populations.

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    Goutam Sahana

    Full Text Available INTRODUCTION: The state-of-the-art for dealing with multiple levels of relationship among the samples in genome-wide association studies (GWAS is unified mixed model analysis (MMA. This approach is very flexible, can be applied to both family-based and population-based samples, and can be extended to incorporate other effects in a straightforward and rigorous fashion. Here, we present a complementary approach, called 'GENMIX (genealogy based mixed model' which combines advantages from two powerful GWAS methods: genealogy-based haplotype grouping and MMA. SUBJECTS AND METHODS: We validated GENMIX using genotyping data of Danish Jersey cattle and simulated phenotype and compared to the MMA. We simulated scenarios for three levels of heritability (0.21, 0.34, and 0.64, seven levels of MAF (0.05, 0.10, 0.15, 0.20, 0.25, 0.35, and 0.45 and five levels of QTL effect (0.1, 0.2, 0.5, 0.7 and 1.0 in phenotypic standard deviation unit. Each of these 105 possible combinations (3 h(2 x 7 MAF x 5 effects of scenarios was replicated 25 times. RESULTS: GENMIX provides a better ranking of markers close to the causative locus' location. GENMIX outperformed MMA when the QTL effect was small and the MAF at the QTL was low. In scenarios where MAF was high or the QTL affecting the trait had a large effect both GENMIX and MMA performed similarly. CONCLUSION: In discovery studies, where high-ranking markers are identified and later examined in validation studies, we therefore expect GENMIX to enrich candidates brought to follow-up studies with true positives over false positives more than the MMA would.

  2. High resolution spatio-temporal mapping of NO2 pollution for estimating personal exposures of the Dutch population

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    Soenario, Ivan; Helbich, Marco; Schmitz, Oliver; Strak, Maciek; Hoek, Gerard; Karssenberg, Derek

    2017-04-01

    Air pollution has been associated with adverse health effects (e.g., cardiovascular and respiration diseases) in the urban environments. Therefore, the assessment of people's exposure to air pollution is central in epidemiological studies. The estimation of exposures on an individual level can be done by combining location information across space and over time with spatio-temporal data on air pollution concentrations. When detailed information on peoples' space-time paths (e.g. commuting patterns calculated by means of spatial routing algorithms or tracked through GPS) and peoples' major activity locations (e.g. home location, work location) are available, it is possible to calculate more precise personal exposure levels depending on peoples' individual space-time mobility patterns. This requires air pollution values not only at a high level of spatial accuracy and high temporal granularity but such data also needs to be available on a nation-wide scale. As current data is seriously limited in this respect, we introduce a novel data set of NO2 levels across the Netherlands. The provided NO2 concentrations are accessible on hourly timestamps on a 5 meter grid cell resolution for weekdays and weekends, and each month of the year. We modeled a single Land Use Regression model using a five year average of NO2 data from the Dutch NO2 measurement network consisting of N=46 sampling locations distributed over the country. Predictor variables for this model were selected in a data-driven manner using an Elastic Net and Best Subset Selection procedure from 70 candidate predictors including traffic, industry, infrastructure and population-based variables. Subsequently, to model NO2 for each time scale (hour, week, month), the LUR coefficients were fitted using the NO2 data, aggregated per time scale. Model validation was grounded on independent data collected in an ad hoc measurement campaign. Our results show a considerable difference in urban concentrations between

  3. A RAD-Based Genetic Map for Anchoring Scaffold Sequences and Identifying QTLs in Bitter Gourd (Momordica charantia

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    Junjie Cui

    2018-04-01

    Full Text Available Genetic mapping is a basic tool necessary for anchoring assembled scaffold sequences and for identifying QTLs controlling important traits. Though bitter gourd (Momordica charantia is both consumed and used as a medicinal, research on its genomics and genetic mapping is severely limited. Here, we report the construction of a restriction site associated DNA (RAD-based genetic map for bitter gourd using an F2 mapping population comprising 423 individuals derived from two cultivated inbred lines, the gynoecious line ‘K44’ and the monoecious line ‘Dali-11.’ This map comprised 1,009 SNP markers and spanned a total genetic distance of 2,203.95 cM across the 11 linkage groups. It anchored a total of 113 assembled scaffolds that covered about 251.32 Mb (85.48% of the 294.01 Mb assembled genome. In addition, three horticulturally important traits including sex expression, fruit epidermal structure, and immature fruit color were evaluated using a combination of qualitative and quantitative data. As a result, we identified three QTL/gene loci responsible for these traits in three environments. The QTL/gene gy/fffn/ffn, controlling sex expression involved in gynoecy, first female flower node, and female flower number was detected in the reported region. Particularly, two QTLs/genes, Fwa/Wr and w, were found to be responsible for fruit epidermal structure and white immature fruit color, respectively. This RAD-based genetic map promotes the assembly of the bitter gourd genome and the identified genetic loci will accelerate the cloning of relevant genes in the future.

  4. A Novel Phytophthora sojae Resistance Rps12 Gene Mapped to a Genomic Region That Contains Several Rps Genes.

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    Sahoo, Dipak K; Abeysekara, Nilwala S; Cianzio, Silvia R; Robertson, Alison E; Bhattacharyya, Madan K

    2017-01-01

    Phytophthora sojae Kaufmann and Gerdemann, which causes Phytophthora root rot, is a widespread pathogen that limits soybean production worldwide. Development of Phytophthora resistant cultivars carrying Phytophthora resistance Rps genes is a cost-effective approach in controlling this disease. For this mapping study of a novel Rps gene, 290 recombinant inbred lines (RILs) (F7 families) were developed by crossing the P. sojae resistant cultivar PI399036 with the P. sojae susceptible AR2 line, and were phenotyped for responses to a mixture of three P. sojae isolates that overcome most of the known Rps genes. Of these 290 RILs, 130 were homozygous resistant, 12 heterzygous and segregating for Phytophthora resistance, and 148 were recessive homozygous and susceptible. From this population, 59 RILs homozygous for Phytophthora sojae resistance and 61 susceptible to a mixture of P. sojae isolates R17 and Val12-11 or P7074 that overcome resistance encoded by known Rps genes mapped to Chromosome 18 were selected for mapping novel Rps gene. A single gene accounted for the 1:1 segregation of resistance and susceptibility among the RILs. The gene encoding the Phytophthora resistance mapped to a 5.8 cM interval between the SSR markers BARCSOYSSR_18_1840 and Sat_064 located in the lower arm of Chromosome 18. The gene is mapped 2.2 cM proximal to the NBSRps4/6-like sequence that was reported to co-segregate with the Phytophthora resistance genes Rps4 and Rps6. The gene is mapped to a highly recombinogenic, gene-rich genomic region carrying several nucleotide binding site-leucine rich repeat (NBS-LRR)-like genes. We named this novel gene as Rps12, which is expected to be an invaluable resource in breeding soybeans for Phytophthora resistance.

  5. A Novel Phytophthora sojae Resistance Rps12 Gene Mapped to a Genomic Region That Contains Several Rps Genes.

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    Dipak K Sahoo

    Full Text Available Phytophthora sojae Kaufmann and Gerdemann, which causes Phytophthora root rot, is a widespread pathogen that limits soybean production worldwide. Development of Phytophthora resistant cultivars carrying Phytophthora resistance Rps genes is a cost-effective approach in controlling this disease. For this mapping study of a novel Rps gene, 290 recombinant inbred lines (RILs (F7 families were developed by crossing the P. sojae resistant cultivar PI399036 with the P. sojae susceptible AR2 line, and were phenotyped for responses to a mixture of three P. sojae isolates that overcome most of the known Rps genes. Of these 290 RILs, 130 were homozygous resistant, 12 heterzygous and segregating for Phytophthora resistance, and 148 were recessive homozygous and susceptible. From this population, 59 RILs homozygous for Phytophthora sojae resistance and 61 susceptible to a mixture of P. sojae isolates R17 and Val12-11 or P7074 that overcome resistance encoded by known Rps genes mapped to Chromosome 18 were selected for mapping novel Rps gene. A single gene accounted for the 1:1 segregation of resistance and susceptibility among the RILs. The gene encoding the Phytophthora resistance mapped to a 5.8 cM interval between the SSR markers BARCSOYSSR_18_1840 and Sat_064 located in the lower arm of Chromosome 18. The gene is mapped 2.2 cM proximal to the NBSRps4/6-like sequence that was reported to co-segregate with the Phytophthora resistance genes Rps4 and Rps6. The gene is mapped to a highly recombinogenic, gene-rich genomic region carrying several nucleotide binding site-leucine rich repeat (NBS-LRR-like genes. We named this novel gene as Rps12, which is expected to be an invaluable resource in breeding soybeans for Phytophthora resistance.

  6. Gene-based single nucleotide polymorphism markers for genetic and association mapping in common bean.

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    Galeano, Carlos H; Cortés, Andrés J; Fernández, Andrea C; Soler, Álvaro; Franco-Herrera, Natalia; Makunde, Godwill; Vanderleyden, Jos; Blair, Matthew W

    2012-06-26

    In common bean, expressed sequence tags (ESTs) are an underestimated source of gene-based markers such as insertion-deletions (Indels) or single-nucleotide polymorphisms (SNPs). However, due to the nature of these conserved sequences, detection of markers is difficult and portrays low levels of polymorphism. Therefore, development of intron-spanning EST-SNP markers can be a valuable resource for genetic experiments such as genetic mapping and association studies. In this study, a total of 313 new gene-based markers were developed at target genes. Intronic variation was deeply explored in order to capture more polymorphism. Introns were putatively identified after comparing the common bean ESTs with the soybean genome, and the primers were designed over intron-flanking regions. The intronic regions were evaluated for parental polymorphisms using the single strand conformational polymorphism (SSCP) technique and Sequenom MassARRAY system. A total of 53 new marker loci were placed on an integrated molecular map in the DOR364 × G19833 recombinant inbred line (RIL) population. The new linkage map was used to build a consensus map, merging the linkage maps of the BAT93 × JALO EEP558 and DOR364 × BAT477 populations. A total of 1,060 markers were mapped, with a total map length of 2,041 cM across 11 linkage groups. As a second application of the generated resource, a diversity panel with 93 genotypes was evaluated with 173 SNP markers using the MassARRAY-platform and KASPar technology. These results were coupled with previous SSR evaluations and drought tolerance assays carried out on the same individuals. This agglomerative dataset was examined, in order to discover marker-trait associations, using general linear model (GLM) and mixed linear model (MLM). Some significant associations with yield components were identified, and were consistent with previous findings. In short, this study illustrates the power of intron-based markers for linkage and association mapping in

  7. Funnel plots and choropleth maps in cancer risk communication: a comparison of tools for disseminating population-based incidence data to stakeholders.

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    Mazzucco, Walter; Cusimano, Rosanna; Zarcone, Maurizio; Mazzola, Sergio; Vitale, Francesco

    2017-03-30

    Population-based cancer registries provide epidemiological cancer information, but the indicators are often too complex to be interpreted by local authorities and communities, due to numeracy and literacy limitations. The aim of this paper is to compare the commonly used visual formats to funnel plots to enable local public health authorities and communities to access valid and understandable cancer incidence data obtained at the municipal level. A funnel plot representation of standardised incidence ratio (SIR) was generated for the 82 municipalities of the Palermo Province with the 2003-2011 data from the Palermo Province Cancer Registry (Sicily, Italy). The properties of the funnel plot and choropleth map methodologies were compared within the context of disseminating epidemiological data to stakeholders. The SIRs of all the municipalities remained within the control limits, except for Palermo city area (SIR=1.12), which was sited outside the upper control limit line of 99.8%. The Palermo Province SIRs funnel plot representation was congruent with the choropleth map generated from the same data, but the former resulted more informative as shown by the comparisons of the weaknesses and strengths of the 2 visual formats. Funnel plot should be used as a complementary valuable tool to communicate epidemiological data of cancer registries to communities and local authorities, visually conveying an efficient and simple way to interpret cancer incidence data. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  8. Identification and fine-mapping of a QTL, qMrdd1, that confers recessive resistance to maize rough dwarf disease.

    Science.gov (United States)

    Tao, Yongfu; Liu, Qingcai; Wang, Honghong; Zhang, Yanjun; Huang, Xinyi; Wang, Baobao; Lai, Jinsheng; Ye, Jianrong; Liu, Baoshen; Xu, Mingliang

    2013-09-30

    Maize rough dwarf disease (MRDD) is a devastating viral disease that results in considerable yield losses worldwide. Three major strains of virus cause MRDD, including maize rough dwarf virus in Europe, Mal de Río Cuarto virus in South America, and rice black-streaked dwarf virus in East Asia. These viral pathogens belong to the genus fijivirus in the family Reoviridae. Resistance against MRDD is a complex trait that involves a number of quantitative trait loci (QTL). The primary approach used to minimize yield losses from these viruses is to breed and deploy resistant maize hybrids. Of the 50 heterogeneous inbred families (HIFs), 24 showed consistent responses to MRDD across different years and locations, in which 9 were resistant and 15 were susceptible. We performed trait-marker association analysis on the 24 HIFs and found six chromosomal regions which were putatively associated with MRDD resistance. We then conducted QTL analysis and detected a major resistance QTL, qMrdd1, on chromosome 8. By applying recombinant-derived progeny testing to self-pollinated backcrossed families, we fine-mapped the qMrdd1 locus into a 1.2-Mb region flanked by markers M103-4 and M105-3. The qMrdd1 locus acted in a recessive manner to reduce the disease-severity index (DSI) by 24.2-39.3%. The genetic effect of qMrdd1 was validated using another F6 recombinant inbred line (RIL) population in which MRDD resistance was segregating and two genotypes at the qMrdd1 locus differed significantly in DSI values. The qMrdd1 locus is a major resistance QTL, acting in a recessive manner to increase maize resistance to MRDD. We mapped qMrdd1 to a 1.2-Mb region, which will enable the introgression of qMrdd1-based resistance into elite maize hybrids and reduce MRDD-related crop losses.

  9. Development of two major resources for pea genomics: the GenoPea 13.2K SNP Array and a high-density, high-resolution consensus genetic map.