A fifth major genetic group among honeybees revealed in Syria.

Science.gov (United States)

Alburaki, Mohamed; Bertrand, Bénédicte; Legout, Hélène; Moulin, Sibyle; Alburaki, Ali; Sheppard, Walter Steven; Garnery, Lionel

2013-12-06

Apiculture has been practiced in North Africa and the Middle-East from antiquity. Several thousand years of selective breeding have left a mosaic of Apis mellifera subspecies in the Middle-East, many uniquely adapted and survived to local environmental conditions. In this study we explore the genetic diversity of A. mellifera from Syria (n = 1258), Lebanon (n = 169) and Iraq (n = 35) based on 14 short tandem repeat (STR) loci in the context of reference populations from throughout the Old World (n = 732). Our data suggest that the Syrian honeybee Apis mellifera syriaca occurs in both Syrian and Lebanese territories, with no significant genetic variability between respective populations from Syria and Lebanon. All studied populations clustered within a new fifth independent nuclear cluster, congruent with an mtDNA Z haplotype identified in a previous study. Syrian honeybee populations are not associated with Oriental lineage O, except for sporadic introgression into some populations close to the Turkish and Iraqi borders. Southern Syrian and Lebanese populations demonstrated high levels of genetic diversity compared to the northern populations. This study revealed the effects of foreign queen importations on Syrian bee populations, especially for the region of Tartus, where extensive introgression of A. m. anatolica and/or A. m. caucasica alleles were identified. The policy of creating genetic conservation centers for the Syrian subspecies should take into consideration the influence of the oriental lineage O from the northern Syrian border and the large population of genetically divergent indigenous honeybees located in southern Syria.

Multilocus genotypic data reveal high genetic diversity and low population genetic structure of Iranian indigenous sheep

International Nuclear Information System (INIS)

Vahidi, S.M.F.; Faruque, M.O.; Falahati Anbaran, M.; Afraz, F.; Mousavi, S.M.; Boettcher, P.; Joost, S.; Han, J.L.; Colli, L.; Periasamy, K.; Negrini, R.; Ajmone-Marsan, P.

2016-01-01

Full text: Iranian livestock diversity is still largely unexplored, in spite of the interest in the populations historically reared in this country located near the Fertile Crescent, a major livestock domestication centre. In this investigation, the genetic diversity and differentiation of 10 Iranian indigenous fat-tailed sheep breeds were investigated using 18 microsatellite markers. Iranian breeds were found to host a high level of diversity. This conclusion is substantiated by the large number of alleles observed across loci (average 13.83, range 7–22) and by the high within-breed expected heterozygosity (average 0.75, range 0.72–0.76). Iranian sheep have a low level of genetic differentiation, as indicated by the analysis of molecular variance, which allocated a very small proportion (1.67%) of total variation to the between-population component, and by the small fixation index (FST = 0.02). Both Bayesian clustering and principal coordinates analysis revealed the absence of a detectable genetic structure. Also, no isolation by distance was observed through comparison of genetic and geographical distances. In spite of high within-breed variation, signatures of inbreeding were detected by the FIS indices, which were positive in all and statistically significant in three breeds. Possible factors explaining the patterns observed, such as considerable gene flow and inbreeding probably due to anthropogenic activities in the light of population management and conservation programmes are discussed. (author)

Phylogeographic analysis reveals significant spatial genetic structure of Incarvillea sinensis as a product of mountain building

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Chen Shaotian

2012-04-01

Full Text Available Abstract Background Incarvillea sinensis is widely distributed from Southwest China to Northeast China and in the Russian Far East. The distribution of this species was thought to be influenced by the uplift of the Qinghai-Tibet Plateau and Quaternary glaciation. To reveal the imprints of geological events on the spatial genetic structure of Incarvillea sinensis, we examined two cpDNA segments ( trnH- psbA and trnS- trnfM in 705 individuals from 47 localities. Results A total of 16 haplotypes was identified, and significant genetic differentiation was revealed (GST =0.843, NST = 0.975, P  Conclusions The results revealed that the uplift of the Qinghai-Tibet Plateau likely resulted in the significant divergence between the lineage in the eastern Qinghai-Tibet Plateau and the other one outside this area. The diverse niches in the eastern Qinghai-Tibet Plateau created a wide spectrum of habitats to accumulate and accommodate new mutations. The features of genetic diversity of populations outside the eastern Qinghai-Tibet Plateau seemed to reveal the imprints of extinction during the Glacial and the interglacial and postglacial recolonization. Our study is a typical case of the significance of the uplift of the Qinghai-Tibet Plateau and the Quaternary Glacial in spatial genetic structure of eastern Asian plants, and sheds new light on the evolution of biodiversity in the Qinghai-Tibet Plateau at the intraspecies level.

Genetic structure of South African Nguni (Zulu) sheep populations reveals admixture with exotic breeds.

Science.gov (United States)

Selepe, Mokhethi Matthews; Ceccobelli, Simone; Lasagna, Emiliano; Kunene, Nokuthula Winfred

2018-01-01

The population of Zulu sheep is reported to have declined by 7.4% between 2007 and 2011 due to crossbreeding. There is insufficient information on the genetic diversity of the Zulu sheep populations in the different area of KwaZulu Natal where they are reared. The study investigated genetic variation and genetic structure within and among eight Zulu sheep populations using 26 microsatellite markers. In addition, Damara, Dorper and South African Merino breeds were included to assess the genetic relationship between these breeds and the Zulu sheep. The results showed that there is considerable genetic diversity among the Zulu sheep populations (expected heterozygosity ranging from 0.57 to 0.69) and the level of inbreeding was not remarkable. The structure analysis results revealed that Makhathini Research Station and UNIZULU research station share common genetic structure, while three populations (Nongoma, Ulundi and Nquthu) had some admixture with the exotic Dorper breed. Thus, there is a need for sustainable breeding and conservation programmes to control the gene flow, in order to stop possible genetic dilution of the Zulu sheep.

Genetic structure of South African Nguni (Zulu sheep populations reveals admixture with exotic breeds.

Directory of Open Access Journals (Sweden)

Mokhethi Matthews Selepe

Full Text Available The population of Zulu sheep is reported to have declined by 7.4% between 2007 and 2011 due to crossbreeding. There is insufficient information on the genetic diversity of the Zulu sheep populations in the different area of KwaZulu Natal where they are reared. The study investigated genetic variation and genetic structure within and among eight Zulu sheep populations using 26 microsatellite markers. In addition, Damara, Dorper and South African Merino breeds were included to assess the genetic relationship between these breeds and the Zulu sheep. The results showed that there is considerable genetic diversity among the Zulu sheep populations (expected heterozygosity ranging from 0.57 to 0.69 and the level of inbreeding was not remarkable. The structure analysis results revealed that Makhathini Research Station and UNIZULU research station share common genetic structure, while three populations (Nongoma, Ulundi and Nquthu had some admixture with the exotic Dorper breed. Thus, there is a need for sustainable breeding and conservation programmes to control the gene flow, in order to stop possible genetic dilution of the Zulu sheep.

Is the Experience of Thermal Pain Genetics Dependent?

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Emilia Horjales-Araujo

2015-01-01

Full Text Available It is suggested that genetic variations explain a significant portion of the variability in pain perception; therefore, increased understanding of pain-related genetic influences may identify new targets for therapies and treatments. The relative contribution of the different genes to the variance in clinical and experimental pain responses remains unknown. It is suggested that the genetic contributions to pain perception vary across pain modalities. For example, it has been suggested that more than 60% of the variance in cold pressor responses can be explained by genetic factors; in comparison, only 26% of the variance in heat pain responses is explained by these variations. Thus, the selection of pain model might markedly influence the magnitude of the association between the pain phenotype and genetic variability. Thermal pain sensation is complex with multiple molecular and cellular mechanisms operating alone and in combination within the peripheral and central nervous system. It is thus highly probable that the thermal pain experience is affected by genetic variants in one or more of the pathways involved in the thermal pain signaling. This review aims to present and discuss some of the genetic variations that have previously been associated with different experimental thermal pain models.

Genetic Diversity of Aromatic Rice Germplasm Revealed By SSR Markers

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Saba Jasim Aljumaili

2018-01-01

Full Text Available Aromatic rice cultivars constitute a small but special group of rice and are considered the best in terms of quality and aroma. Aroma is one of the most significant quality traits of rice, and variety with aroma has a higher price in the market. This research was carried out to study the genetic diversity among the 50 aromatic rice accessions from three regions (Peninsular Malaysia, Sabah, and Sarawak with 3 released varieties as a control using the 32 simple sequence repeat (SSR markers. The objectives of this research were to quantify the genetic divergence of aromatic rice accessions using SSR markers and to identify the potential accessions for introgression into the existing rice breeding program. Genetic diversity index among the three populations such as Shannon information index (I ranged from 0.25 in control to 0.98 in Sabah population. The mean numbers of effective alleles and Shannon’s information index were 0.36 and 64.90%, respectively. Similarly, the allelic diversity was very high with mean expected heterozygosity (He of 0.60 and mean Nei’s gene diversity index of 0.36. The dendrogram based on UPGMA and Nei’s genetic distance classified the 53 rice accessions into 10 clusters. Analysis of molecular variance (AMOVA revealed that 89% of the total variation observed in this germplasm came from within the populations, while 11% of the variation emanated among the populations. These results reflect the high genetic differentiation existing in this aromatic rice germplasm. Using all these criteria and indices, seven accessions (Acc9993, Acc6288, Acc6893, Acc7580, Acc6009, Acc9956, and Acc11816 from three populations have been identified and selected for further evaluation before introgression into the existing breeding program and for future aromatic rice varietal development.

Genetic Diversity of Aromatic Rice Germplasm Revealed By SSR Markers.

Science.gov (United States)

Jasim Aljumaili, Saba; Rafii, M Y; Latif, M A; Sakimin, Siti Zaharah; Arolu, Ibrahim Wasiu; Miah, Gous

2018-01-01

Aromatic rice cultivars constitute a small but special group of rice and are considered the best in terms of quality and aroma. Aroma is one of the most significant quality traits of rice, and variety with aroma has a higher price in the market. This research was carried out to study the genetic diversity among the 50 aromatic rice accessions from three regions (Peninsular Malaysia, Sabah, and Sarawak) with 3 released varieties as a control using the 32 simple sequence repeat (SSR) markers. The objectives of this research were to quantify the genetic divergence of aromatic rice accessions using SSR markers and to identify the potential accessions for introgression into the existing rice breeding program. Genetic diversity index among the three populations such as Shannon information index ( I ) ranged from 0.25 in control to 0.98 in Sabah population. The mean numbers of effective alleles and Shannon's information index were 0.36 and 64.90%, respectively. Similarly, the allelic diversity was very high with mean expected heterozygosity ( H e ) of 0.60 and mean Nei's gene diversity index of 0.36. The dendrogram based on UPGMA and Nei's genetic distance classified the 53 rice accessions into 10 clusters. Analysis of molecular variance (AMOVA) revealed that 89% of the total variation observed in this germplasm came from within the populations, while 11% of the variation emanated among the populations. These results reflect the high genetic differentiation existing in this aromatic rice germplasm. Using all these criteria and indices, seven accessions (Acc9993, Acc6288, Acc6893, Acc7580, Acc6009, Acc9956, and Acc11816) from three populations have been identified and selected for further evaluation before introgression into the existing breeding program and for future aromatic rice varietal development.

Genetic Diversity of Aromatic Rice Germplasm Revealed By SSR Markers

Science.gov (United States)

Jasim Aljumaili, Saba; Sakimin, Siti Zaharah; Arolu, Ibrahim Wasiu; Miah, Gous

2018-01-01

Aromatic rice cultivars constitute a small but special group of rice and are considered the best in terms of quality and aroma. Aroma is one of the most significant quality traits of rice, and variety with aroma has a higher price in the market. This research was carried out to study the genetic diversity among the 50 aromatic rice accessions from three regions (Peninsular Malaysia, Sabah, and Sarawak) with 3 released varieties as a control using the 32 simple sequence repeat (SSR) markers. The objectives of this research were to quantify the genetic divergence of aromatic rice accessions using SSR markers and to identify the potential accessions for introgression into the existing rice breeding program. Genetic diversity index among the three populations such as Shannon information index (I) ranged from 0.25 in control to 0.98 in Sabah population. The mean numbers of effective alleles and Shannon's information index were 0.36 and 64.90%, respectively. Similarly, the allelic diversity was very high with mean expected heterozygosity (He) of 0.60 and mean Nei's gene diversity index of 0.36. The dendrogram based on UPGMA and Nei's genetic distance classified the 53 rice accessions into 10 clusters. Analysis of molecular variance (AMOVA) revealed that 89% of the total variation observed in this germplasm came from within the populations, while 11% of the variation emanated among the populations. These results reflect the high genetic differentiation existing in this aromatic rice germplasm. Using all these criteria and indices, seven accessions (Acc9993, Acc6288, Acc6893, Acc7580, Acc6009, Acc9956, and Acc11816) from three populations have been identified and selected for further evaluation before introgression into the existing breeding program and for future aromatic rice varietal development. PMID:29736396

Geographical gradients in selection can reveal genetic constraints for evolutionary responses to ocean acidification.

Science.gov (United States)

Gaitán-Espitia, Juan Diego; Marshall, Dustin; Dupont, Sam; Bacigalupe, Leonardo D; Bodrossy, Levente; Hobday, Alistair J

2017-02-01

Geographical gradients in selection can shape different genetic architectures in natural populations, reflecting potential genetic constraints for adaptive evolution under climate change. Investigation of natural pH/pCO 2 variation in upwelling regions reveals different spatio-temporal patterns of natural selection, generating genetic and phenotypic clines in populations, and potentially leading to local adaptation, relevant to understanding effects of ocean acidification (OA). Strong directional selection, associated with intense and continuous upwellings, may have depleted genetic variation in populations within these upwelling regions, favouring increased tolerances to low pH but with an associated cost in other traits. In contrast, diversifying or weak directional selection in populations with seasonal upwellings or outside major upwelling regions may have resulted in higher genetic variances and the lack of genetic correlations among traits. Testing this hypothesis in geographical regions with similar environmental conditions to those predicted under climate change will build insights into how selection may act in the future and how populations may respond to stressors such as OA. © 2017 The Author(s).

Dual gene activation and knockout screen reveals directional dependencies in genetic networks. | Office of Cancer Genomics

Science.gov (United States)

Understanding the direction of information flow is essential for characterizing how genetic networks affect phenotypes. However, methods to find genetic interactions largely fail to reveal directional dependencies. We combine two orthogonal Cas9 proteins from Streptococcus pyogenes and Staphylococcus aureus to carry out a dual screen in which one gene is activated while a second gene is deleted in the same cell. We analyze the quantitative effects of activation and knockout to calculate genetic interaction and directionality scores for each gene pair.

Matrilineal Heritage in Southern Iberia Reveals Deep Genetic Links between Continents.

Science.gov (United States)

Hernández, Candela L; Calderón, Rosario

2017-03-01

Within the Mediterranean Basin, the Iberian Peninsula has been a focus of attraction for several cultures and civilizations from its prehistory and history, making it a target territory for studying human migration patterns and peopling processes using a wide and heterogeneous spectrum of genomic markers. While its Cantabrian fringe represents the most regularly analysed area in terms of its mitochondrial diversity, the absence of monographic surveys on the maternal genetic composition of southern Iberians (i.e., Andalusians) is striking. In this work, we present a comprehensive view of various aspects of the human maternal heritage of the autochthonous Andalusian population regarding specific mitochondrial haplogroups considered key candidates to determine the genetic relationship between Europe and Africa. Data reveal that southern Iberian populations do not have genetically homogeneous mitochondrial DNA profiles, and their observed genetic affinity with north-western African populations represents strong signals of old, sustained and bidirectional human movements between the northern and southern shores of the western Mediterranean. Thorough analyses of African mtDNA haplogroups have shown that the most relevant African contribution within Iberian Peninsula could be explained as a consequence of prehistoric events. The subsequent historic episodes helped to strengthen the ties between both shores. In southern Iberia, mitochondrial and other genetic markers show that the Strait of Gibraltar together with its surrounding maritime areas should be considered a bridge between continents. More broadly, the Mediterranean Sea has acted as a transport surface, that is, as a permeable barrier to human migrations from prehistoric and historic times. In conclusion, this research contributes to our knowledge of processes that have shaped the recent human genetic history in the Mediterranean and, more specifically, of the population dynamics that the inhabitants of southern

Genetic variation architecture of mitochondrial genome reveals the differentiation in Korean landrace and weedy rice

OpenAIRE

Wei Tong; Qiang He; Yong-Jin Park

2017-01-01

Mitochondrial genome variations have been detected despite the overall conservation of this gene content, which has been valuable for plant population genetics and evolutionary studies. Here, we describe mitochondrial variation architecture and our performance of a phylogenetic dissection of Korean landrace and weedy rice. A total of 4,717 variations across the mitochondrial genome were identified adjunct with 10 wild rice. Genetic diversity assessment revealed that wild rice has higher nucle...

Homozygosity mapping and targeted sanger sequencing reveal genetic defects underlying inherited retinal disease in families from pakistan.

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Maleeha Maria

Full Text Available Homozygosity mapping has facilitated the identification of the genetic causes underlying inherited diseases, particularly in consanguineous families with multiple affected individuals. This knowledge has also resulted in a mutation dataset that can be used in a cost and time effective manner to screen frequent population-specific genetic variations associated with diseases such as inherited retinal disease (IRD.We genetically screened 13 families from a cohort of 81 Pakistani IRD families diagnosed with Leber congenital amaurosis (LCA, retinitis pigmentosa (RP, congenital stationary night blindness (CSNB, or cone dystrophy (CD. We employed genome-wide single nucleotide polymorphism (SNP array analysis to identify homozygous regions shared by affected individuals and performed Sanger sequencing of IRD-associated genes located in the sizeable homozygous regions. In addition, based on population specific mutation data we performed targeted Sanger sequencing (TSS of frequent variants in AIPL1, CEP290, CRB1, GUCY2D, LCA5, RPGRIP1 and TULP1, in probands from 28 LCA families.Homozygosity mapping and Sanger sequencing of IRD-associated genes revealed the underlying mutations in 10 families. TSS revealed causative variants in three families. In these 13 families four novel mutations were identified in CNGA1, CNGB1, GUCY2D, and RPGRIP1.Homozygosity mapping and TSS revealed the underlying genetic cause in 13 IRD families, which is useful for genetic counseling as well as therapeutic interventions that are likely to become available in the near future.

Genetic Counseling Supervisors' Self-Efficacy for Select Clinical Supervision Competencies.

Science.gov (United States)

Finley, Sabra Ledare; Veach, Pat McCarthy; MacFarlane, Ian M; LeRoy, Bonnie S; Callanan, Nancy

2016-04-01

Supervision is a primary instructional vehicle for genetic counseling student clinical training. Approximately two-thirds of genetic counselors report teaching and education roles, which include supervisory roles. Recently, Eubanks Higgins and colleagues published the first comprehensive list of empirically-derived genetic counseling supervisor competencies. Studies have yet to evaluate whether supervisors possess these competencies and whether their competencies differ as a function of experience. This study investigated three research questions: (1) What are genetic counselor supervisors' perceptions of their capabilities (self-efficacy) for a select group of supervisor competencies?, (2) Are there differences in self-efficacy as a function of their supervision experience or their genetic counseling experience, and 3) What training methods do they use and prefer to develop supervision skills? One-hundred thirty-one genetic counselor supervisors completed an anonymous online survey assessing demographics, self-efficacy (self-perceived capability) for 12 goal setting and 16 feedback competencies (Scale: 0-100), competencies that are personally challenging, and supervision training experiences and preferences (open-ended). A MANOVA revealed significant positive effects of supervision experience but not genetic counseling experience on participants' self-efficacy. Although mean self-efficacy ratings were high (>83.7), participant comments revealed several challenging competencies (e.g., incorporating student's report of feedback from previous supervisors into goal setting, and providing feedback about student behavior rather than personal traits). Commonly preferred supervision training methods included consultation with colleagues, peer discussion, and workshops/seminars.

Whole Exome Sequencing Reveals Genetic Predisposition in a Large Family with Retinitis Pigmentosa

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Juan Wu

2014-01-01

Full Text Available Next-generation sequencing has become more widely used to reveal genetic defect in monogenic disorders. Retinitis pigmentosa (RP, the leading cause of hereditary blindness worldwide, has been attributed to more than 67 disease-causing genes. Due to the extreme genetic heterogeneity, using general molecular screening alone is inadequate for identifying genetic predispositions in susceptible individuals. In order to identify underlying mutation rapidly, we utilized next-generation sequencing in a four-generation Chinese family with RP. Two affected patients and an unaffected sibling were subjected to whole exome sequencing. Through bioinformatics analysis and direct sequencing confirmation, we identified p.R135W transition in the rhodopsin gene. The mutation was subsequently confirmed to cosegregate with the disease in the family. In this study, our results suggest that whole exome sequencing is a robust method in diagnosing familial hereditary disease.

Genetic variation and geographical differentiation revealed using ...

Indian Academy of Sciences (India)

there are a few reports on the genetic evaluation of tung tree germplasm. .... bES, Enshi in Hubei province; SN, Suining in Sichuan province. Journal of Genetics Vol. 94, Online Resources e6 ... gene diversity. Journal of Genetics Vol. 94, Online Resources e7 .... Pan Y., Pan L., Chen L., Zhang L. L., Nevo E. and Peng J. H..

The genetic basis of evolutionary change

National Research Council Canada - National Science Library

Lewontin, Richard C

1974-01-01

In this volume the author surveys the many experiments using new molecular techniques that have revealed the enormous wealth of hereditary variation among individuals and have quantified the genetic...

Genetic Diversity of Selected Mangifera Species Revealed by Inter Simple Sequence Repeats Markers

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Zulhairil Ariffin

2015-01-01

Full Text Available ISSR markers were employed to reveal genetic diversity and genetic relatedness among 28 Mangifera accessions collected from Yan (Kedah, Bukit Gantang (Perak, Sibuti (Sarawak, and Papar (Sabah. A total of 198 markers were generated using nine anchored primers and one nonanchored primer. Genetic variation among the 28 accessions of Mangifera species including wild relatives, landraces, and clonal varieties is high, with an average degree of polymorphism of 98% and mean Shannon index, H0=7.50. Analysis on 18 Mangifera indica accessions also showed high degree of polymorphism of 99% and mean Shannon index, H0=5.74. Dice index of genetic similarity ranged from 0.0938 to 0.8046 among the Mangifera species. The dendrogram showed that the Mangifera species were grouped into three main divergent clusters. Cluster 1 comprised 14 accessions from Kedah and Perak. Cluster II and cluster III comprised 14 accessions from Sarawak and Sabah. Meanwhile, the Dice index of genetic similarity for 18 accessions of Mangifera indica ranged from 0.2588 to 0.7742. The dendrogram also showed the 18 accessions of Mangifera indica were grouped into three main clusters. Cluster I comprised 10 landraces of Mangifera indica from Kedah. Cluster II comprised 7 landraces of Mangifera indica followed by Chokanan to form Cluster III.

Genetic Diversity of the Critically Endangered Thuja sutchuenensis Revealed by ISSR Markers and the Implications for Conservation

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Zeping Jiang

2013-07-01

Full Text Available Thuja sutchuenensis Franch. is a critically endangered plant endemic to the North-East Chongqing, China. Genetic variation was studied to assess the distribution of genetic diversity within and among seven populations from the single remnant locations, using inter-simple sequence repeat (ISSR markers. A total of 15 primers generated 310 well defined bands, with an average of 20.7 bands per primer. The seven populations revealed a relatively high level of genetic diversity in the species. The percentage of polymorphic bands, Nei’s gene diversity and Shannon’s information index at the population and species level were 76.1%, 0.155, 0.252 and 100%, 0.165, 0.295, respectively. A low level of genetic differentiation among populations (GST = 0.102, in line with the results of Analyses of Molecular Variance (AMOVA, and a high level of gene flow (Nm = 4.407 were observed. Both the Unweighted Pair Group Method with Arithmatic Mean (UPGMA cluster analysis and Principal Coordinates Analysis (PCoA supported the grouping of all seven populations into two groups. In addition, Mantel test revealed no significant correlation between genetic and geographical distances (r = 0.329, p = 0.100. The low genetic differentiation among populations implies that the conservation efforts should aim to preserve all the extant populations of this endangered species.

Fine-scale genetic structure and cryptic associations reveal evidence of kin-based sociality in the African forest elephant.

Science.gov (United States)

Schuttler, Stephanie G; Philbrick, Jessica A; Jeffery, Kathryn J; Eggert, Lori S

2014-01-01

Spatial patterns of relatedness within animal populations are important in the evolution of mating and social systems, and have the potential to reveal information on species that are difficult to observe in the wild. This study examines the fine-scale genetic structure and connectivity of groups within African forest elephants, Loxodonta cyclotis, which are often difficult to observe due to forest habitat. We tested the hypothesis that genetic similarity will decline with increasing geographic distance, as we expect kin to be in closer proximity, using spatial autocorrelation analyses and Tau K(r) tests. Associations between individuals were investigated through a non-invasive genetic capture-recapture approach using network models, and were predicted to be more extensive than the small groups found in observational studies, similar to fission-fusion sociality found in African savanna (Loxodonta africana) and Asian (Elephas maximus) species. Dung samples were collected in Lopé National Park, Gabon in 2008 and 2010 and genotyped at 10 microsatellite loci, genetically sexed, and sequenced at the mitochondrial DNA control region. We conducted analyses on samples collected at three different temporal scales: a day, within six-day sampling sessions, and within each year. Spatial autocorrelation and Tau K(r) tests revealed genetic structure, but results were weak and inconsistent between sampling sessions. Positive spatial autocorrelation was found in distance classes of 0-5 km, and was strongest for the single day session. Despite weak genetic structure, individuals within groups were significantly more related to each other than to individuals between groups. Social networks revealed some components to have large, extensive groups of up to 22 individuals, and most groups were composed of individuals of the same matriline. Although fine-scale population genetic structure was weak, forest elephants are typically found in groups consisting of kin and based on matrilines

Genetic variation in Phoca vitulina (the harbour seal) revealed by DNA fingerprinting and RAPDs

NARCIS (Netherlands)

Kappe, A.L.; van de Zande, L.; Vedder, E.J.; Bijlsma, R.; van Delden, Wilke

Genetic variation in two harbour seal (Phoca vitulina) populations from the Dutch Wadden Sea and Scotland was examined by RAPD analysis and DNA fingerprinting. For comparison a population of grey seals (Halichoerus grypus) was studied. The RAPD method revealed a very low number of polymorphic bands.

Genetic Risk by Experience Interaction for Childhood Internalizing Problems: Converging Evidence across Multiple Methods

Science.gov (United States)

Vendlinski, Matthew K.; Lemery-Chalfant, Kathryn; Essex, Marilyn J.; Goldsmith, H. Hill

2011-01-01

Background: Identifying how genetic risk interacts with experience to predict psychopathology is an important step toward understanding the etiology of mental health problems. Few studies have examined genetic risk by experience interaction (GxE) in the development of childhood psychopathology. Methods: We used both co-twin and parent mental…

Genetic diversity of worldwide Jerusalem artichoke (Helianthus tuberosus) germplasm as revealed by RAPD markers.

Science.gov (United States)

Wangsomnuk, P P; Khampa, S; Wangsomnuk, P; Jogloy, S; Mornkham, T; Ruttawat, B; Patanothai, A; Fu, Y B

2011-12-12

Jerusalem artichoke (Helianthus tuberosus) is a wild relative of the cultivated sunflower (H. annuus); it is an old tuber crop that has recently received renewed interest. We used RAPD markers to characterize 147 Jerusalem artichoke accessions from nine countries. Thirty RAPD primers were screened; 13 of them detected 357 reproducible RAPD bands, of which 337 were polymorphic. Various diversity analyses revealed several different patterns of RAPD variation. More than 93% of the RAPD variation was found within accessions of a country. Weak genetic differentiation was observed between wild and cultivated accessions. Six groups were detected in this germplasm set. Four ancestral groups were found for the Canadian germplasm. The most genetically distinct accessions were identified. These findings provide useful diversity information for understanding the Jerusalem artichoke gene pool, for conserving Jerusalem artichoke germplasm, and for choosing germplasm for genetic improvement.

Mitochondrial DNA reveals genetic structuring of Pinna nobilis across the Mediterranean Sea.

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Daria Sanna

Full Text Available Pinna nobilis is the largest endemic Mediterranean marine bivalve. During past centuries, various human activities have promoted the regression of its populations. As a consequence of stringent standards of protection, demographic expansions are currently reported in many sites. The aim of this study was to provide the first large broad-scale insight into the genetic variability of P. nobilis in the area that encompasses the western Mediterranean, Ionian Sea, and Adriatic Sea marine ecoregions. To accomplish this objective twenty-five populations from this area were surveyed using two mitochondrial DNA markers (COI and 16S. Our dataset was then merged with those obtained in other studies for the Aegean and Tunisian populations (eastern Mediterranean, and statistical analyses (Bayesian model-based clustering, median-joining network, AMOVA, mismatch distribution, Tajima's and Fu's neutrality tests and Bayesian skyline plots were performed. The results revealed genetic divergence among three distinguishable areas: (1 western Mediterranean and Ionian Sea; (2 Adriatic Sea; and (3 Aegean Sea and Tunisian coastal areas. From a conservational point of view, populations from the three genetically divergent groups found may be considered as different management units.

Gregor Mendel's Genetic Experiments: A Statistical Analysis after 150 Years

Czech Academy of Sciences Publication Activity Database

Kalina, Jan

2016-01-01

Roč. 12, č. 2 (2016), s. 20-26 ISSN 1801-5603 Institutional support: RVO:67985807 Keywords : genetics * history of science * biostatistics * design of experiments Subject RIV: BB - Applied Statistics, Operational Research

Simplification of genotyping techniques of the ABO blood type experiment and exploration of population genetics.

Science.gov (United States)

Hu, Jian; Zhou, Yi-ren; Ding, Jia-lin; Wang, Zhi-yuan; Liu, Ling; Wang, Ye-kai; Lou, Hui-ling; Qiao, Shou-yi; Wu, Yan-hua

2017-05-20

The ABO blood type is one of the most common and widely used genetic traits in humans. Three glycosyltransferase-encoding gene alleles, I A , I B and i, produce three red blood cell surface antigens, by which the ABO blood type is classified. By using the ABO blood type experiment as an ideal case for genetics teaching, we can easily introduce to the students several genetic concepts, including multiple alleles, gene interaction, single nucleotide polymorphism (SNP) and gene evolution. Herein we have innovated and integrated our ABO blood type genetics experiments. First, in the section of Molecular Genetics, a new method of ABO blood genotyping was established: specific primers based on SNP sites were designed to distinguish three alleles through quantitative real-time PCR. Next, the experimental teaching method of Gene Evolution was innovated in the Population Genetics section: a gene-evolution software was developed to simulate the evolutionary tendency of the ABO genotype encoding alleles under diverse conditions. Our reform aims to extend the contents of genetics experiments, to provide additional teaching approaches, and to improve the learning efficiency of our students eventually.

"Am I carrier?" The patient's lived experience of thrombophilia genetic screening and its outcome.

Science.gov (United States)

Graffigna, Guendalina; Leone, Daniela; Vegni, Elena

2014-01-01

How do patients with thrombophilia experience a physician's request to undergo a genetic test? How do they experience the test outcome? To answer these questions, we conducted an interpretative phenomenological analysis study, based on 10 in-depth interviews with patients who underwent genetic testing for thrombophilia in Italy, half with positive and half with negative results. The experience of undergoing genetic screening for thrombophilia plays an important role in reconfiguring patients' signification of their illness experience. A positive outcome becomes a cue to reorganize in a more adaptive way the illness meaning at the cognitive and emotive levels, whereas a negative outcome appears more distressing and confusing. As a clinical implication of the study, clinicians should consider communicating carefully with the patients regardless from the positive/negative test results and they should explore the patient's specific reaction and understanding of test result.

Fine-scale genetic structure and cryptic associations reveal evidence of kin-based sociality in the African forest elephant.

Directory of Open Access Journals (Sweden)

Stephanie G Schuttler

Full Text Available Spatial patterns of relatedness within animal populations are important in the evolution of mating and social systems, and have the potential to reveal information on species that are difficult to observe in the wild. This study examines the fine-scale genetic structure and connectivity of groups within African forest elephants, Loxodonta cyclotis, which are often difficult to observe due to forest habitat. We tested the hypothesis that genetic similarity will decline with increasing geographic distance, as we expect kin to be in closer proximity, using spatial autocorrelation analyses and Tau K(r tests. Associations between individuals were investigated through a non-invasive genetic capture-recapture approach using network models, and were predicted to be more extensive than the small groups found in observational studies, similar to fission-fusion sociality found in African savanna (Loxodonta africana and Asian (Elephas maximus species. Dung samples were collected in Lopé National Park, Gabon in 2008 and 2010 and genotyped at 10 microsatellite loci, genetically sexed, and sequenced at the mitochondrial DNA control region. We conducted analyses on samples collected at three different temporal scales: a day, within six-day sampling sessions, and within each year. Spatial autocorrelation and Tau K(r tests revealed genetic structure, but results were weak and inconsistent between sampling sessions. Positive spatial autocorrelation was found in distance classes of 0-5 km, and was strongest for the single day session. Despite weak genetic structure, individuals within groups were significantly more related to each other than to individuals between groups. Social networks revealed some components to have large, extensive groups of up to 22 individuals, and most groups were composed of individuals of the same matriline. Although fine-scale population genetic structure was weak, forest elephants are typically found in groups consisting of kin and

Genetic diversity of Nostoc microsymbionts from Gunnera tinctoria revealed by PCR-STRR fingerprinting.

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Guevara, R; Armesto, J J; Caru, M

2002-08-01

The cyanobacteria belonging to the genus Nostoc fix atmospheric nitrogen, both as free-living organisms and in symbiotic associations with a wide range of hosts, including bryophytes, gymnosperms (cycads), the small water fern Azolla (Pteridophyte), the angiosperm genus Gunnera, and fungi (lichens). The Gunnera-Nostoc symbiosis is the only one that involves a flowering plant. In Chile, 12 species of Gunnera have been described with a broad distribution in the temperate region. We examined the genetic diversity of Nostoc symbionts from three populations of Gunnera tinctoria from Abtao, Chiloé Island, southern Chile, and microsymbionts from other two species of Gunnera from southern Chile, using PCR amplification of STRR (short tandemly repeated repetitive) sequences of the Nostoc infected tissue. To our knowledge, this is the first report of PCR fingerprinting obtained directly from symbiotic tissue of Gunnera. Genetic analyses revealed that Nostoc symbionts exhibit important genetic diversity among host plants, both within and between Gunnera populations. It was also found that only one Nostoc strain, or closely related strains, established symbiosis with an individual plant host.

Market organization and animal genetic resource management: a revealed preference analysis of sheep pricing.

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Tindano, K; Moula, N; Leroy, P; Traoré, A; Antoine-Moussiaux, N

2017-10-01

Farm animal genetic resources are threatened worldwide. Participation in markets, while representing a crucial way out of poverty for many smallholders, affects genetic management choices with associated sustainability concerns. This paper proposes a contextualized study of the interactions between markets and animal genetic resources management, in the case of sheep markets in Ouagadougou, Burkina Faso. It focusses on the organization of marketing chains and the valuation of genetic characteristics by value chain actors. Marketing chain characterization was tackled through semi-structured interviews with 25 exporters and 15 butchers, both specialized in sheep. Moreover, revealed preference methods were applied to analyse the impact of animals' attributes on market pricing. Data were collected from 338 transactions during three different periods: Eid al-Adha, Christmas and New Year period, and a neutral period. The neutral period is understood as a period not close to any event likely to influence the demand for sheep. The results show that physical characteristics such as live weight, height at withers and coat colour have a strong influence on the animals' prices. Live weight has also had an increasing marginal impact on price. The different markets (local butcher, feasts, export market, sacrifices) represent distinct demands for genetic characteristics, entailing interesting consequences for animal genetic resource management. Any breeding programme should therefore take this diversity into account to allow this sector to contribute better to a sustainable development of the country.

Genetic Interaction Maps in Escherichia coli Reveal Functional Crosstalk among Cell Envelope Biogenesis Pathways

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Vlasblom, James; Gagarinova, Alla; Phanse, Sadhna; Graham, Chris; Yousif, Fouad; Ding, Huiming; Xiong, Xuejian; Nazarians-Armavil, Anaies; Alamgir, Md; Ali, Mehrab; Pogoutse, Oxana; Pe'er, Asaf; Arnold, Roland; Michaut, Magali; Parkinson, John; Golshani, Ashkan; Whitfield, Chris; Wodak, Shoshana J.; Moreno-Hagelsieb, Gabriel; Greenblatt, Jack F.; Emili, Andrew

2011-01-01

As the interface between a microbe and its environment, the bacterial cell envelope has broad biological and clinical significance. While numerous biosynthesis genes and pathways have been identified and studied in isolation, how these intersect functionally to ensure envelope integrity during adaptive responses to environmental challenge remains unclear. To this end, we performed high-density synthetic genetic screens to generate quantitative functional association maps encompassing virtually the entire cell envelope biosynthetic machinery of Escherichia coli under both auxotrophic (rich medium) and prototrophic (minimal medium) culture conditions. The differential patterns of genetic interactions detected among >235,000 digenic mutant combinations tested reveal unexpected condition-specific functional crosstalk and genetic backup mechanisms that ensure stress-resistant envelope assembly and maintenance. These networks also provide insights into the global systems connectivity and dynamic functional reorganization of a universal bacterial structure that is both broadly conserved among eubacteria (including pathogens) and an important target. PMID:22125496

Genetic interaction maps in Escherichia coli reveal functional crosstalk among cell envelope biogenesis pathways.

Directory of Open Access Journals (Sweden)

Mohan Babu

2011-11-01

Full Text Available As the interface between a microbe and its environment, the bacterial cell envelope has broad biological and clinical significance. While numerous biosynthesis genes and pathways have been identified and studied in isolation, how these intersect functionally to ensure envelope integrity during adaptive responses to environmental challenge remains unclear. To this end, we performed high-density synthetic genetic screens to generate quantitative functional association maps encompassing virtually the entire cell envelope biosynthetic machinery of Escherichia coli under both auxotrophic (rich medium and prototrophic (minimal medium culture conditions. The differential patterns of genetic interactions detected among > 235,000 digenic mutant combinations tested reveal unexpected condition-specific functional crosstalk and genetic backup mechanisms that ensure stress-resistant envelope assembly and maintenance. These networks also provide insights into the global systems connectivity and dynamic functional reorganization of a universal bacterial structure that is both broadly conserved among eubacteria (including pathogens and an important target.

High-Throughput Phenotyping and QTL Mapping Reveals the Genetic Architecture of Maize Plant Growth.

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Zhang, Xuehai; Huang, Chenglong; Wu, Di; Qiao, Feng; Li, Wenqiang; Duan, Lingfeng; Wang, Ke; Xiao, Yingjie; Chen, Guoxing; Liu, Qian; Xiong, Lizhong; Yang, Wanneng; Yan, Jianbing

2017-03-01

With increasing demand for novel traits in crop breeding, the plant research community faces the challenge of quantitatively analyzing the structure and function of large numbers of plants. A clear goal of high-throughput phenotyping is to bridge the gap between genomics and phenomics. In this study, we quantified 106 traits from a maize ( Zea mays ) recombinant inbred line population ( n = 167) across 16 developmental stages using the automatic phenotyping platform. Quantitative trait locus (QTL) mapping with a high-density genetic linkage map, including 2,496 recombinant bins, was used to uncover the genetic basis of these complex agronomic traits, and 988 QTLs have been identified for all investigated traits, including three QTL hotspots. Biomass accumulation and final yield were predicted using a combination of dissected traits in the early growth stage. These results reveal the dynamic genetic architecture of maize plant growth and enhance ideotype-based maize breeding and prediction. © 2017 American Society of Plant Biologists. All Rights Reserved.

Genetic diversity and substantial population differentiation in Crassostrea hongkongensis revealed by mitochondrial DNA.

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Li, Lu; Wu, Xiangyun; Yu, Ziniu

2013-09-01

The Hong Kong oyster, Crassostrea hongkongensis, is an important fisheries resource that is cultivated in the coastal waters of the South China Sea. Despite significant advances in understanding biological and taxonomic aspects of this species, no detailed study of its population genetic diversity in regions of extensive cultivation are available. Direct sequencing of the mtDNA cox1 gene region was used to investigate genetic variation within and between eleven C. hongkongensis populations collected from typical habitats. Sixty-two haplotypes were identified; only haplotype 2 (21.74% of total haplotypes) was shared among all the eleven populations, and most of the observed haplotypes were restricted to individual populations. Both AMOVA and FST analyses revealed significant population structure, and the isolation by distance (IBD) was confirmed. The highest local differentiation was observed between the sample pools from Guangxi versus Guangdong and Fujian, which are separated by a geographic barrier, the Leizhou Peninsula. Current knowledge from seed management suggests that seed transfer from Guangxi province has likely reduced the divergence that somewhat naturally exists between these pools. The findings from the present study could be useful for genetic management and may serve as a baseline by which to monitor future changes in genetic diversity, either due to natural or anthropogenic impacts. Copyright © 2013 Elsevier B.V. All rights reserved.

Disability Experiences and Perspectives Regarding Reproductive Decisions, Parenting, and the Utility of Genetic Services: a Qualitative Study.

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Roadhouse, C; Shuman, C; Anstey, K; Sappleton, K; Chitayat, D; Ignagni, E

2018-06-16

Genetic counselors adopt seemingly contradictory roles: advocating for individuals with genetic conditions while offering prenatal diagnosis and the option of selective termination to prevent the birth of a child with a disability. This duality contributes to the tension between the disability and clinical genetics communities. Varying opinions exist amongst the disability community: some value genetic services while others are opposed. However, there is limited research exploring the opinions of individuals with a disability regarding issues related to reproduction and genetic services in the context of personal experience. This exploratory qualitative study involved interviews with seven women and three men who self-identify as having a disability. We sought to gain their perspectives on experiences with disability, thoughts about reproduction and parenting, and perceptions of genetic services. Transcripts of the interviews were analyzed thematically using qualitative content analysis. Data analysis showed that societal views of disability affected the lived experience and impacted reproductive decision-making for those with a disability. It also showed differing interest in genetic services. Concerns about the perceived collective implications of genetic services were also raised. These findings contribute to the understanding of the disability perspective toward reproductive decision-making and genetic services. A further goal is to promote a meaningful dialogue between the genetics and disability communities, with the potential to enhance the genetic and reproductive care provided to individuals with disabilities.

Genetic and epigenetic divergence between disturbed and undisturbed subpopulations of a Mediterranean shrub: a 20-year field experiment.

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Herrera, Carlos M; Bazaga, Pilar

2016-06-01

Little is known on the potential of ecological disturbance to cause genetic and epigenetic changes in plant populations. We take advantage of a long-term field experiment initiated in 1986 to study the demography of the shrub Lavandula latifolia , and compare genetic and epigenetic characteristics of plants in two adjacent subplots, one experimentally disturbed and one left undisturbed, 20 years after disturbance. Experimental setup was comparable to an unreplicated 'Before-After-Control-Impact' (BACI) design where a single pair of perturbed and control areas were compared. When sampled in 2005, plants in the two subplots had roughly similar ages, but they had established in contrasting environments: dense conspecific population ('Undisturbed' subpopulation) versus open area with all conspecifics removed ('Disturbed' subpopulation). Plants were characterized genetically and epigenetically using amplified fragment length polymorphism (AFLP) and two classes of methylation-sensitive AFLP (MSAP) markers. Subpopulations were similar in genetic diversity but differed in epigenetic diversity and multilocus genetic and epigenetic characteristics. Epigenetic divergence between subpopulations was statistically unrelated to genetic divergence. Bayesian clustering revealed an abrupt linear boundary between subpopulations closely coincident with the arbitrary demarcation line between subplots drawn 20 years back, which supports that genetic and epigenetic divergence between subpopulations was caused by artificial disturbance. There was significant fine-scale spatial structuring of MSAP markers in both subpopulations, which in the Undisturbed one was indistinguishable from that of AFLP markers. Genetic differences between subpopulations could be explained by divergent selection alone, while the concerted action of divergent selection and disturbance-driven appearance of new methylation variants in the Disturbed subpopulation is proposed to explain epigenetic differences. This

University Students’ Reflections on Representations in Genetics and Stereochemistry Revealed by a Focus Group Approach

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Inger Edfors

2015-05-01

Full Text Available Genetics and organic chemistry are areas of science that students regard as difficult to learn. Part of this difficulty is derived from the disciplines having representations as part of their discourses. In order to optimally support students’ meaning-making, teachers need to use representations to structure the meaning-making experience in thoughtful ways that consider the variation in students’ prior knowledge. Using a focus group setting, we explored 43 university students’ reasoning on representations in introductory chemistry and genetics courses. Our analysis of eight focus group discussions revealed how students can construct somewhat bewildered relations with disciplinary-specific representations. The students stated that they preferred familiar representations, but without asserting the meaning-making affordances of those representations. Also, the students were highly aware of the affordances of certain representations, but nonetheless chose not to use those representations in their problem solving. We suggest that an effective representation is one that, to some degree, is familiar to the students, but at the same time is challenging and not too closely related to “the usual one”. The focus group discussions led the students to become more aware of their own and others ways of interpreting different representations. Furthermore, feedback from the students’ focus group discussions enhanced the teachers’ awareness of the students’ prior knowledge and limitations in students’ representational literacy. Consequently, we posit that a focus group setting can be used in a university context to promote both student meaning-making and teacher professional development in a fruitful way.

Attitudes Toward Pre-implantation Genetic Diagnosis (PGD) for Genetic Disorders Among Potential Users in Malaysia.

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Olesen, Angelina Patrick; Nor, Siti Nurani Mohd; Amin, Latifah

2016-02-01

While pre-implantation genetic diagnosis (PGD) is available and legal in Malaysia, there is an ongoing controversy debate about its use. There are few studies available on individuals' attitudes toward PGD, particularly among those who have a genetic disease, or whose children have a genetic disease. To the best of our knowledge, this is, in fact, the first study of its kind in Malaysia. We conducted in-depth interviews, using semi-structured questionnaires, with seven selected potential PGD users regarding their knowledge, attitudes and decisions relating to the use PGD. The criteria for selecting potential PGD users were that they or their children had a genetic disease, and they desired to have another child who would be free of genetic disease. All participants had heard of PGD and five of them were considering its use. The participants' attitudes toward PGD were based on several different considerations that were influenced by various factors. These included: the benefit-risk balance of PGD, personal experiences of having a genetic disease, religious beliefs, personal values and cost. The study's findings suggest that the selected Malaysian participants, as potential PGD users, were supportive but cautious regarding the use of PGD for medical purposes, particularly in relation to others whose experiences were similar. More broadly, the paper highlights the link between the participants' personal experiences and their beliefs regarding the appropriateness, for others, of individual decision-making on PGD, which has not been revealed by previous studies.

Genetic Diversity and Population Structure of the Critically Endangered Yangtze Finless Porpoise (Neophocaena asiaeorientalis asiaeorientalis as Revealed by Mitochondrial and Microsatellite DNA

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Minmin Chen

2014-06-01

Full Text Available Ecological surveys have indicated that the population of the critically endangered Yangtze finless porpoise (YFP, Neophocaena asiaeorientalis asiaeorientalis is becoming increasingly small and fragmented, and will be at high risk of extinction in the near future. Genetic conservation of this population will be an important component of the long-term conservation effort. We used a 597 base pair mitochondrial DNA (mtDNA control region and 11 microsatellite loci to analyze the genetic diversity and population structure of the YFP. The analysis of both mtDNA and microsatellite loci suggested that the genetic diversity of the YFP will possibly decrease in the future if the population keeps declining at a rapid rate, even though these two types of markers revealed different levels of genetic diversity. In addition, mtDNA revealed strong genetic differentiation between one local population, Xingchang–Shishou (XCSS, and the other five downstream local populations; furthermore, microsatellite DNA unveiled fine but significant genetic differentiation between three of the local populations (not only XCSS but also Poyang Lake (PY and Tongling (TL and the other local populations. With an increasing number of distribution gaps appearing in the Yangtze main steam, the genetic differentiation of local populations will likely intensify in the future. The YFP is becoming a genetically fragmented population. Therefore, we recommend attention should be paid to the genetic conservation of the YFP.

Genetic Diversity and Population Structure of the Critically Endangered Yangtze Finless Porpoise (Neophocaena asiaeorientalis asiaeorientalis) as Revealed by Mitochondrial and Microsatellite DNA

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Chen, Minmin; Zheng, Jinsong; Wu, Min; Ruan, Rui; Zhao, Qingzhong; Wang, Ding

2014-01-01

Ecological surveys have indicated that the population of the critically endangered Yangtze finless porpoise (YFP, Neophocaena asiaeorientalis asiaeorientalis) is becoming increasingly small and fragmented, and will be at high risk of extinction in the near future. Genetic conservation of this population will be an important component of the long-term conservation effort. We used a 597 base pair mitochondrial DNA (mtDNA) control region and 11 microsatellite loci to analyze the genetic diversity and population structure of the YFP. The analysis of both mtDNA and microsatellite loci suggested that the genetic diversity of the YFP will possibly decrease in the future if the population keeps declining at a rapid rate, even though these two types of markers revealed different levels of genetic diversity. In addition, mtDNA revealed strong genetic differentiation between one local population, Xingchang–Shishou (XCSS), and the other five downstream local populations; furthermore, microsatellite DNA unveiled fine but significant genetic differentiation between three of the local populations (not only XCSS but also Poyang Lake (PY) and Tongling (TL)) and the other local populations. With an increasing number of distribution gaps appearing in the Yangtze main steam, the genetic differentiation of local populations will likely intensify in the future. The YFP is becoming a genetically fragmented population. Therefore, we recommend attention should be paid to the genetic conservation of the YFP. PMID:24968271

Vantage Sensitivity: Environmental Sensitivity to Positive Experiences as a Function of Genetic Differences.

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Pluess, Michael

2017-02-01

A large number of gene-environment interaction studies provide evidence that some people are more likely to be negatively affected by adverse experiences as a function of specific genetic variants. However, such "risk" variants are surprisingly frequent in the population. Evolutionary analysis suggests that genetic variants associated with increased risk for maladaptive development under adverse environmental conditions are maintained in the population because they are also associated with advantages in response to different contextual conditions. These advantages may include (a) coexisting genetic resilience pertaining to other adverse influences, (b) a general genetic susceptibility to both low and high environmental quality, and (c) a coexisting propensity to benefit disproportionately from positive and supportive exposures, as reflected in the recent framework of vantage sensitivity. After introducing the basic properties of vantage sensitivity and highlighting conceptual similarities and differences with diathesis-stress and differential susceptibility patterns of gene-environment interaction, selected and recent empirical evidence for the notion of vantage sensitivity as a function of genetic differences is reviewed. The unique contribution that the new perspective of vantage sensitivity may make to our understanding of social inequality will be discussed after suggesting neurocognitive and molecular mechanisms hypothesized to underlie the propensity to benefit disproportionately from benevolent experiences. © 2015 Wiley Periodicals, Inc.

Genetic classes and genetic categories : Protecting genetic groups through data protection law

NARCIS (Netherlands)

Hallinan, Dara; de Hert, Paul; Taylor, L.; Floridi, L.; van der Sloot, B.

2017-01-01

Each person shares genetic code with others. Thus, one individual’s genome can reveal information about other individuals. When multiple individuals share aspects of genetic architecture, they form a ‘genetic group’. From a social and legal perspective, two types of genetic group exist: Those which

Preferences of newborn mice for odours indicating closer genetic relatedness: is experience necessary?

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Todrank, Josephine; Busquet, Nicolas; Baudoin, Claude; Heth, Giora

2005-10-07

Evidence from studies with adult rodents indicates that individual recognition enables distinctions between familiar individuals irrespective of relatedness (but including close kin) and a separate mechanism enables discriminations based on genetic relatedness without prior familiarity. For example, adult mice could assess the extent of their genetic relatedness to unfamiliar individuals using perceptual similarities between their individual odours. The ontogeny of this genetic relatedness assessment mechanism, however, had not been investigated. Here, in two-choice tests, newborn mice differentially preferred odours of more genetically similar lactating females (paternal aunts to unrelated conspecific and conspecific to heterospecific) even without prior direct exposure to adults with the tested genotypes. The results provide a direct demonstration of genetic relatedness assessment abilities in newborns and show that experience with parental odours is not necessary for genetic relatedness distinctions. Future studies will be necessary to determine whether exposure to odours of other foetuses in the womb or littermates shortly after birth affects this genetic relatedness assessment process.

Microsatellite genotyping reveals high genetic diversity but low ...

African Journals Online (AJOL)

JMwacharos

2016-03-16

Mar 16, 2016 ... diversity and (2) Investigate population structure and extent of admixture .... to estimate and partition genetic variation within and ... K between 1 and 40 and inferred its most optimal value ... populations of 0.84 ± 0.021 with the lowest mean in ..... on population stratification and the distribution of genetic.

U.S. Adults with Agricultural Experience Report More Genetic Engineering Familiarity than Those Without

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Stofer, Kathryn A.; Schiebel, Tracee M.

2017-01-01

Researchers and pollsters still debate the acceptance of genetic engineering technology among U.S. adults, and continue to assess their knowledge as part of this research. While decision-making may not rely entirely on knowledge, querying opinions and perceptions rely on public understanding of genetic engineering terms. Experience with…

Friendship Experiences and Anxiety Among Children: A Genetically Informed Study.

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Poirier, Catherine Serra; Brendgen, Mara; Girard, Alain; Vitaro, Frank; Dionne, Ginette; Boivin, Michel

2016-01-01

This study examined (a) whether, in line with a gene-environment correlation (rGE), a genetic disposition for anxiety puts children at risk of having anxious friends or having no reciprocal friends; (b) to what extent these friendship experiences are related to anxiety symptoms, when controlling for sex and genetic disposition for this trait; and (c) the additive and interactive predictive links of the reciprocal best friend's anxiety symptoms and of friendship quality with children's anxiety symptoms. Using a genetically informed design based on 521 monozygotic and ic twins (264 girls; 87% of European descent) assessed in Grade 4 (M age = 10.04 years, SD = .26), anxiety symptoms and perceived friendship quality were measured with self-report questionnaires. Results indicated that, in line with rGE, children with a strong genetic disposition for anxiety were more likely to have anxious friends than nonanxious friends. Moreover, controlling for their genetic risk for anxiety, children with anxious friends showed higher levels of anxiety symptoms than children with nonanxious friends but did not differ from those without reciprocal friends. Additional analyses suggested a possible contagion of anxiety symptoms between reciprocal best friends when perceived negative features of friendship were high. These results underline the importance of teaching strategies such as problem solving that enhance friendship quality to limit the potential social contagion of anxiety symptoms.

Genetic Diversity of Pinus nigra Arn. Populations in Southern Spain and Northern Morocco Revealed By Inter-Simple Sequence Repeat Profiles

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Oussama Ahrazem

2012-05-01

Full Text Available Eight Pinus nigra Arn. populations from Southern Spain and Northern Morocco were examined using inter-simple sequence repeat markers to characterize the genetic variability amongst populations. Pair-wise population genetic distance ranged from 0.031 to 0.283, with a mean of 0.150 between populations. The highest inter-population average distance was between PaCU from Cuenca and YeCA from Cazorla, while the lowest distance was between TaMO from Morocco and MA Sierra Mágina populations. Analysis of molecular variance (AMOVA and Nei’s genetic diversity analyses revealed higher genetic variation within the same population than among different populations. Genetic differentiation (Gst was 0.233. Cuenca showed the highest Nei’s genetic diversity followed by the Moroccan region, Sierra Mágina, and Cazorla region. However, clustering of populations was not in accordance with their geographical locations. Principal component analysis showed the presence of two major groups—Group 1 contained all populations from Cuenca while Group 2 contained populations from Cazorla, Sierra Mágina and Morocco—while Bayesian analysis revealed the presence of three clusters. The low genetic diversity observed in PaCU and YeCA is probably a consequence of inappropriate management since no estimation of genetic variability was performed before the silvicultural treatments. Data indicates that the inter-simple sequence repeat (ISSR method is sufficiently informative and powerful to assess genetic variability among populations of P. nigra.

RAPID-COMMUNICATION Genetic diversity and differentiation in natural populations of Arapaima gigas from lower Amazon revealed by microsatellites.

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Fazzi-Gomes, P F; Melo, N; Palheta, G; Guerreiro, S; Amador, M; Ribeiro-Dos-Santos, A K; Santos, S; Hamoy, I

2017-02-08

Genetic variability is one of the important criteria for species conservation decisions. This study aimed to analyze the genetic diversity and the population differentiation of two natural populations of Arapaima gigas, a species with a long history of being commercially exploited. We collected 87 samples of A. gigas from Grande Curuai Lake and Paru Lake, located in the Lower Amazon region of Amazônia, Brazil, and genotyped these samples using a multiplex panel of microsatellite markers. Our results showed that the populations of A. gigas analyzed had high levels of genetic variability, which were similar to those described in previous studies. These two populations had a significant population differentiation supported by the estimates of F ST and R ST (0.06), by Bayesian analysis (K = 2), and by population assignment tests, which revealed a moderate genetic distance.

Association genetics and transcriptome analysis reveal a gibberellin-responsive pathway involved in regulating photosynthesis.

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Xie, Jianbo; Tian, Jiaxing; Du, Qingzhang; Chen, Jinhui; Li, Ying; Yang, Xiaohui; Li, Bailian; Zhang, Deqiang

2016-05-01

Gibberellins (GAs) regulate a wide range of important processes in plant growth and development, including photosynthesis. However, the mechanism by which GAs regulate photosynthesis remains to be understood. Here, we used multi-gene association to investigate the effect of genes in the GA-responsive pathway, as constructed by RNA sequencing, on photosynthesis, growth, and wood property traits, in a population of 435 Populus tomentosa By analyzing changes in the transcriptome following GA treatment, we identified many key photosynthetic genes, in agreement with the observed increase in measurements of photosynthesis. Regulatory motif enrichment analysis revealed that 37 differentially expressed genes related to photosynthesis shared two essential GA-related cis-regulatory elements, the GA response element and the pyrimidine box. Thus, we constructed a GA-responsive pathway consisting of 47 genes involved in regulating photosynthesis, including GID1, RGA, GID2, MYBGa, and 37 photosynthetic differentially expressed genes. Single nucleotide polymorphism (SNP)-based association analysis showed that 142 SNPs, representing 40 candidate genes in this pathway, were significantly associated with photosynthesis, growth, and wood property traits. Epistasis analysis uncovered interactions between 310 SNP-SNP pairs from 37 genes in this pathway, revealing possible genetic interactions. Moreover, a structural gene-gene matrix based on a time-course of transcript abundances provided a better understanding of the multi-gene pathway affecting photosynthesis. The results imply a functional role for these genes in mediating photosynthesis, growth, and wood properties, demonstrating the potential of combining transcriptome-based regulatory pathway construction and genetic association approaches to detect the complex genetic networks underlying quantitative traits. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights

The Genetic Relationship between Leishmania aethiopica and Leishmania tropica Revealed by Comparing Microsatellite Profiles.

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Krayter, Lena; Schnur, Lionel F; Schönian, Gabriele

2015-01-01

Leishmania (Leishmania) aethiopica and L. (L.) tropica cause cutaneous leishmaniases and appear to be related. L. aethiopica is geographically restricted to Ethiopia and Kenya; L. tropica is widely dispersed from the Eastern Mediterranean, through the Middle East into eastern India and in north, east and south Africa. Their phylogenetic inter-relationship is only partially revealed. Some studies indicate a close relationship. Here, eight strains of L. aethiopica were characterized genetically and compared with 156 strains of L. tropica from most of the latter species' geographical range to discern the closeness. Twelve unlinked microsatellite markers previously used to genotype strains of L. tropica were successfully applied to the eight strains of L. aethiopica and their microsatellite profiles were compared to those of 156 strains of L. tropica from various geographical locations that were isolated from human cases of cutaneous and visceral leishmaniasis, hyraxes and sand fly vectors. All the microsatellite profiles were subjected to various analytical algorithms: Bayesian statistics, distance-based and factorial correspondence analysis, revealing: (i) the species L. aethiopica, though geographically restricted, is genetically very heterogeneous; (ii) the strains of L. aethiopica formed a distinct genetic cluster; and (iii) strains of L. aethiopica are closely related to strains of L. tropica and more so to the African ones, although, by factorial correspondence analysis, clearly separate from them. The successful application of the 12 microsatellite markers, originally considered species-specific for the species L. tropica, to strains of L. aethiopica confirmed the close relationship between these two species. The Bayesian and distance-based methods clustered the strains of L. aethiopica among African strains of L. tropica, while the factorial correspondence analysis indicated a clear separation between the two species. There was no correlation between

A complex scenario of tuberculosis transmission is revealed through genetic and epidemiological surveys in Porto.

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Rito, Teresa; Matos, Carlos; Carvalho, Carlos; Machado, Henrique; Rodrigues, Gabriela; Oliveira, Olena; Ferreira, Eduarda; Gonçalves, Jorge; Maio, Lurdes; Morais, Clara; Ramos, Helena; Guimarães, João Tiago; Santos, Catarina L; Duarte, Raquel; Correia-Neves, Margarida

2018-01-25

Tuberculosis (TB) incidence is decreasing worldwide and eradication is becoming plausible. In low-incidence countries, intervention on migrant populations is considered one of the most important strategies for elimination. However, such measures are inappropriate in European areas where TB is largely endemic, such as Porto in Portugal. We aim to understand transmission chains in Porto through a genetic characterization of Mycobacterium tuberculosis strains and through a detailed epidemiological evaluation of cases. We genotyped the M. tuberculosis strains using the MIRU-VNTR system. We performed an evolutionary reconstruction of the genotypes with median networks, used in this context for the first time. TB cases from a period of two years were evaluated combining genetic, epidemiological and georeferencing information. The data reveal a unique complex scenario in Porto where the autochthonous population acts as a genetic reservoir of M. tuberculosis diversity with discreet episodes of transmission, mostly undetected using classical epidemiology alone. Although control policies have been successful in decreasing incidence in Porto, the discerned complexity suggests that, for elimination to be a realistic goal, strategies need to be adjusted and coupled with a continuous genetic characterization of strains and detailed epidemiological evaluation, in order to successfully identify and interrupt transmission chains.

Genetic and environmental contributions to the inverse association between specific autistic traits and experience seeking in adults.

Science.gov (United States)

Romero-Martínez, Ángel; Moya-Albiol, Luís; Vinkhuyzen, Anna A E; Polderman, Tinca J C

2016-12-01

Autistic traits are characterized by social and communication problems, restricted, repetitive and stereotyped patterns of behavior, interests and activities. The relation between autistic traits and personality characteristics is largely unknown. This study focused on the relation between five specific autistic traits measured with the abridged version of the Autism Spectrum Quotient ("social problems," "preference for routine," "attentional switching difficulties," "imagination impairments," "fascination for numbers and patterns") and Experience Seeking (ES) in a general population sample of adults, and subsequently investigated the genetic and environmental etiology between these traits. Self-reported data on autistic traits and ES were collected in a population sample (n = 559) of unrelated individuals, and in a population based family sample of twins and siblings (n = 560). Phenotypic, genetic and environmental associations between traits were examined in a bivariate model, accounting for sex and age differences. Phenotypically, ES correlated significantly with "preference for routine" and "imagination impairments" in both samples but was unrelated to the other autistic traits. Genetic analyses in the family sample revealed that the association between ES and "preference for routine" and "imagination impairments" could largely be explained by a shared genetic factor (89% and 70%, respectively). Our analyses demonstrated at a phenotypic and genetic level an inverse relationship between ES and specific autistic traits in adults. ES is associated with risk taking behavior such as substance abuse, antisocial behavior and financial problems. Future research could investigate whether autistic traits, in particular strong routine preference and impaired imagination skills, serve as protective factors for such risky behaviors. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Farmers' valuation of incentives to produce genetically modified organism-free milk: Insights from a discrete choice experiment in Germany.

Science.gov (United States)

Schreiner, J A; Latacz-Lohmann, U

2015-11-01

This paper investigates farmers' willingness to participate in a genetically modified organism (GMO)-free milk production scheme offered by some German dairy companies. The empirical analysis is based upon discrete choice experiments with 151 dairy farmers from 2 regions in Germany. A conditional logit estimation reveals a strong positive effect of the price premium on offer. Reliable feed monitoring and free technical support increase the likelihood of scheme adoption, the latter however only in farms that have been receiving technical support in other fields. By contrast, any interference with the entrepreneurial autonomy of farmers, through pre-arranged feed procurement or prescriptive advice on the part of the dairy company, lowers acceptance probabilities. Farmers' attitudes toward cultivation of genetically modified soy, their assessment of the market potential of GMO-free milk and future feed prices were found to be significant determinants of adoption, as are farmer age, educational status, and current feeding regimens. Respondents requested on average a mark-up of 0.80 eurocents per kilogram of milk to accept a contract. Comparison of the estimates for the 2 regions suggests that farmers in northern Germany are, on average, more likely to convert to genetically modified-free production; however, farmers in the south are, ceteris paribus, more responsive to an increase in the price premium offered. A latent class model reveals significant differences in the valuation of scheme attributes between 2 latent classes of adopters and nonadopters. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Population genetics of Sargassum horneri (Fucales, Phaeophyta) in China revealed by ISSR and SRAP markers

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Yu, Shenhui; Chong, Zhuo; Zhao, Fengjuan; Yao, Jianting; Duan, Delin

2013-05-01

Sargassum horneri is a common brown macro-alga that is found in the inter-tidal ecosystems of China. To investigate the current status of seaweed resources and provide basic data for its sustainable development, ISSR (inter simple sequence repeat) and SRAP (sequence related amplified polymorphism) markers were used to analyze the population genetics among nine natural populations of S. horneri. The nine studied populations were distributed over 2 000 km from northeast to south China. The percentage of polymorphic loci P % (ISSR, 99.44%; SRAP, 100.00%), Nei's genetic diversity H (ISSR, 0.107-0.199; SRAP, 0.100-0.153), and Shannon's information index I (ISSR, 0.157-0.291; SRAP, 0.148-0.219) indicated a fair amount of genetic variability among the nine populations. Moreover, the high degree of gene differentiation G st (ISSR, 0.654; SRAP, 0.718) and low gene flow N m (ISSR, 0.265; SRAP, 0.196) implied that there was significant among-population differentiation, possibly as a result of habitat fragmentation. The matrices of genetic distances and fixation indices ( F st) among the populations correlated well with their geographical distribution (Mantel test R =0.541 5, 0.541 8; P =0.005 0, 0.002 0 and R =0.728 6, 0.641 2; P =0.001 0, 0.001 0, respectively); the Rongcheng population in the Shandong peninsula was the only exception. Overall, the genetic differentiation agreed with the geographic isolation. The fair amount of genetic diversity that was revealed in the S. horneri populations in China indicated that the seaweed resources had not been seriously affected by external factors.

High-Throughput Phenotyping and QTL Mapping Reveals the Genetic Architecture of Maize Plant Growth1[OPEN

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Huang, Chenglong; Wu, Di; Qiao, Feng; Li, Wenqiang; Duan, Lingfeng; Wang, Ke; Xiao, Yingjie; Chen, Guoxing; Liu, Qian; Yang, Wanneng

2017-01-01

With increasing demand for novel traits in crop breeding, the plant research community faces the challenge of quantitatively analyzing the structure and function of large numbers of plants. A clear goal of high-throughput phenotyping is to bridge the gap between genomics and phenomics. In this study, we quantified 106 traits from a maize (Zea mays) recombinant inbred line population (n = 167) across 16 developmental stages using the automatic phenotyping platform. Quantitative trait locus (QTL) mapping with a high-density genetic linkage map, including 2,496 recombinant bins, was used to uncover the genetic basis of these complex agronomic traits, and 988 QTLs have been identified for all investigated traits, including three QTL hotspots. Biomass accumulation and final yield were predicted using a combination of dissected traits in the early growth stage. These results reveal the dynamic genetic architecture of maize plant growth and enhance ideotype-based maize breeding and prediction. PMID:28153923

Genetic diversity of grape germplasm as revealed by microsatellite ...

African Journals Online (AJOL)

aghomotsegin

In this work, cluster analysis and principal component analysis (PCA) were used to study the genetic ... Key words: Vitis vinifera L., simple sequence repeat (SSR), genetic diversity, .... The data were used for the following statistical analyses.

Genetics, morphology and ecology reveal a cryptic pika lineage in the Sikkim Himalaya.

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Dahal, Nishma; Lissovsky, Andrey A; Lin, Zhenzhen; Solari, Katherine; Hadly, Elizabeth A; Zhan, Xiangjiang; Ramakrishnan, Uma

2017-01-01

Asian pika species are morphologically ∼similar and have overlapping ranges. This leads to uncertainty and species misidentification in the field. Phylogenetic analyses of such misidentified samples leads to taxonomic ambiguity. The ecology of many pika species remains understudied, particularly in the Himalaya, where sympatric species could be separated by elevation and/or substrate. We sampled, measured, and acquired genetic data from pikas in the Sikkim Himalaya. Our analyses revealed a cryptic lineage, Ochotona sikimaria, previously reported as a subspecies of O. thibetana. The results support the elevation of this lineage to the species level, as it is genetically divergent from O. thibetana, as well as sister species, O. cansus (endemic to central China) and O. curzoniae (endemic to the Tibetan plateau). The Sikkim lineage diverged from its sister species' about 1.7-0.8myrago, coincident with uplift events in the Himalaya. Our results add to the recent spate of cryptic diversity identified from the eastern Himalaya and highlight the need for further study within the Ochotonidae. Copyright © 2016 Elsevier Inc. All rights reserved.

Inter-embodiment and the experience of genetic testing for familial hypercholesterolaemia.

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Jenkins, Nicholas; Lawton, Julia; Douglas, Margaret; Hallowell, Nina

2013-05-01

In this article we explore the concept of inter-embodiment and its potential for advancing sociological research into illness biography and genetic identity. Inter-embodiment theory views embodied knowledge as produced through relations between bodies, as opposed to originating from within the body or as the product of relations between disembodied selves. Drawing on a qualitative study in which we interviewed 38 individuals about their experiences of discovering they had high cholesterol and undergoing genetic testing for familial hypercholesterolaemia (FH), we discuss how their narratives may be understood from an inter-embodiment perspective. The participants frequently talked at length about their family histories of high cholesterol and cardiovascular disease. Through these accounts, we develop the concept of the family corpus in order to highlight the role body networks play in shaping lay constructions of genetic identity and a familial disease biography. The notion of a family corpus, we argue, is useful in understanding why genetic testing for FH was experienced as either biographical re-enforcement or as biographical disruption. We conclude by discussing the implications of our findings for future sociological research into illness biography and genetic identity. © 2012 The Authors. Sociology of Health & Illness © 2012 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.

Molecular Characterization and Genetic Diversity of the Macaw Palm Ex Situ Germplasm Collection Revealed by Microsatellite Markers

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Fekadu G. Mengistu

2016-10-01

Full Text Available Macaw palm (Acrocomia aculeata is native to tropical forests in South America and highly abundant in Brazil. It is cited as a highly productive oleaginous palm tree presenting high potential for biodiesel production. The aim of this work was to characterize and study the genetic diversity of A. aculeata ex situ collections from different geographical states in Brazil using microsatellite (Simple Sequence Repeats, SSR markers. A total of 192 accessions from 10 provenances were analyzed with 10 SSR, and variations were detected in allelic diversity, polymorphism, and heterozygosity in the collections. Three major groups of accessions were formed using PCoA—principal coordinate analysis, UPGMA—unweighted pair-group method with arithmetic mean, and Tocher. The Mantel test revealed a weak correlation (r = 0.07 between genetic and geographic distances among the provenances reaffirming the result of the grouping. Reduced average heterozygosity (Ho < 50% per locus (or provenance confirmed the predominance of endogamy (or inbreeding in the germplasm collections as evidenced by positive inbreeding coefficient (F > 0 per locus (or per provenance. AMOVA—Analysis of Molecular Variance revealed higher (48.2% genetic variation within population than among populations (36.5%. SSR are useful molecular markers in characterizing A. aculeata germplasm and could facilitate the process of identifying, grouping, and selecting genotypes. Present results could be used to formulate appropriate conservation strategies in the genebank.

Comparative riverscape genetics reveals reservoirs of genetic diversity for conservation and restoration of Great Plains fishes.

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Osborne, Megan J; Perkin, Joshuah S; Gido, Keith B; Turner, Thomas F

2014-12-01

We used comparative landscape genetics to examine the relative roles of historical events, intrinsic traits and landscape factors in determining the distribution of genetic diversity of river fishes across the North American Great Plains. Spatial patterns of diversity were overlaid on a patch-based graphical model and then compared within and among three species that co-occurred across five Great Plains watersheds. Species differing in reproductive strategy (benthic vs. pelagic-spawning) were hypothesized to have different patterns of genetic diversity, but the overriding factor shaping contemporary patterns of diversity was the signature of past climates and geological history. Allelic diversity was significantly higher at southern latitudes for Cyprinella lutrensis and Hybognathus placitus, consistent with northward expansion from southern Pleistocene refugia. Within the historical context, all species exhibited lowered occupancy and abundance in heavily fragmented and drier upstream reaches, particularly H. placitus; a pelagic-spawning species, suggesting rates of extirpation have outpaced losses of genetic diversity in this species. Within most tributary basins, genetically diverse populations of each species persisted. Hence, reconnecting genetically diverse populations with those characterized by reduced diversity (regardless of their position within the riverine network) would provide populations with greater genetic and demographic resilience. We discuss cases where cross-basin transfer may be appropriate to enhance genetic diversity and mitigate negative effects of climate change. Overall, striking similarities in genetic patterns and in response to fragmentation and dewatering suggest a common strategy for genetic resource management in this unique riverine fish assemblage. © 2014 John Wiley & Sons Ltd.

Genetic differences among Haplorchis taichui populations in Indochina revealed by mitochondrial COX1 sequences.

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Thaenkham, U; Phuphisut, O; Nuamtanong, S; Yoonuan, T; Sa-Nguankiat, S; Vonghachack, Y; Belizario, V Y; Dung, D T; Dekumyoy, P; Waikagul, J

2017-09-01

Haplorchis taichui is an intestinal heterophyid fluke that is pathogenic to humans. It is widely distributed in Asia, with a particularly high prevalence in Indochina. Previous work revealed that the lack of gene flow between three distinct populations of Vietnamese H. taichui can be attributed to their geographic isolation with no interconnected river basins. To test the hypothesis that interconnected river basins allow gene flow between otherwise isolated populations of H. taichui, as previously demonstrated for another trematode, Opisthorchis viverrini, we compared the genetic structures of seven populations of H. taichui from various localities in the lower Mekong Basin, in Thailand and Laos, with those in Vietnam, using the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene. To determine the gene flow between these H. taichui populations, we calculated their phylogenetic relationships, genetic distances and haplotype diversity. Each population showed very low nucleotide diversity at this locus. However, high levels of genetic differentiation between the populations indicated very little gene flow. A phylogenetic analysis divided the populations into four clusters that correlated with the country of origin. The negligible gene flow between the Thai and Laos populations, despite sharing the Mekong Basin, caused us to reject our hypothesis. Our data suggest that the distribution of H. taichui populations was incidentally associated with national borders.

What do consumer surveys and experiments reveal and conceal about consumer preferences for genetically modified foods?

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Colson, Gregory; Rousu, Matthew C

2013-01-01

Assessing consumer perceptions and willingness to pay for genetically modified (GM) foods has been one of the most active areas of empirical research in agricultural economics. Researchers over the past 15 years have delivered well over 100 estimates of consumers' willingness to pay for GM foods using surveys and experimental methods. In this review, we explore a number of unresolved issues related to three questions that are critical when considering the sum of the individual contributions that constitute the evidence on consumer preferences for GM foods.

Genetic similarity of soybean genotypes revealed by seed protein

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Nikolić Ana

2005-01-01

Full Text Available More accurate and complete descriptions of genotypes could help determinate future breeding strategies and facilitate introgression of new genotypes in current soybean genetic pool. The objective of this study was to characterize 20 soybean genotypes from the Maize Research Institute "Zemun Polje" collection, which have good agronomic performances, high yield, lodging and drought resistance, and low shuttering by seed proteins as biochemical markers. Seed proteins were isolated and separated by PAA electrophoresis. On the basis of the presence/absence of protein fractions coefficients of similarity were calculated as Dice and Roger and Tanamoto coefficient between pairs of genotypes. The similarity matrix was submitted for hierarchical cluster analysis of un weighted pair group using arithmetic average (UPGMA method and necessary computation were performed using NTSYS-pc program. Protein seed analysis confirmed low level of genetic diversity in soybean. The highest genetic similarity was between genotypes P9272 and Kador. According to obtained results, soybean genotypes were assigned in two larger groups and coefficients of similarity showed similar results. Because of the lack of pedigree data for analyzed genotypes, correspondence with marker data could not be determined. In plant with a narrow genetic base in their gene pool, such as soybean, protein markers may not be sufficient for characterization and study of genetic diversity.

Genetic variation and comparison of orchardgrass (Dactylis glomerata L.) cultivars and wild accessions as revealed by SSR markers.

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Xie, W G; Lu, X F; Zhang, X Q; Huang, L K; Cheng, L

2012-02-24

Orchardgrass is a highly variable, perennial forage grass that is cultivated throughout temperate and subtropical regions of the world. Despite its economic importance, the genetic relationship and distance among and within cultivars are largely unknown but would be of great interest for breeding programs. We investigated the molecular variation and structure of cultivar populations, compared the level of genetic diversity among cultivars (Baoxing, Anba, Bote, and Kaimo), subspecies (Dactylis glomerata ssp Woronowii) and advanced breeding line (YA02-116) to determine whether there is still sufficient genetic diversity within presently used cultivars for future breeding progress in China. Twenty individuals were analyzed from each of six accessions using SSR markers; 114 easily scored bands were generated from 15 SSR primer pairs, with an average of 7.6 alleles per locus. The polymorphic rate was 100% among the 120 individuals, reflecting a high degree of genetic diversity. Among the six accessions, the highest genetic diversity was observed in Kaimo (H = 0.2518; I = 0.3916; P = 87.3%) and 02-116 had a lower level of genetic diversity (H = 0.1806; I = 0.2788; P = 58.73%) compared with other cultivars tested. An of molecular variance revealed a much larger genetic variation within accessions (65%) than between them (35%). This observation suggests that these cultivars have potential for providing rich genetic resource for further breeding program. Furthermore, the study also indicated that Chinese orchardgrass breeding has involved strong selection for adaptation to forage production, which may result in restricted genetic base of orchardgrass cultivar.

Microsatellite markers reveal low genetic differentiation among ...

African Journals Online (AJOL)

Ben

Assignment. 1* Khai Apple Game Reserve, Kathu, Northern Cape ... Previous genetic studies on Camelidae in Dubai, Germany, Australia, Kenya and Ethiopia mainly reporting the ... All the biological samples were deposited in the Bio-Bank at.

Genetic Divergence in Sugarcane Genotypes

OpenAIRE

Tahir, Mohammad; Rahman, Hidayatur; Gul, Rahmani; Ali, Amjad; Khalid, Muhammad

2012-01-01

To assess genetic divergence of sugarcane germplasm, an experiment comprising 25 sugarcane genotypes was conducted at Sugar Crops Research Institute (SCRI), Mardan, Khyber Pakhtunkhwa, Pakistan, in quadruple lattice design during 2008-09. Among the 14 parameters evaluated, majority exhibited significant differences while some showed nonsignificant mean squares. The initial correlation matrix revealed medium to high correlations. Principal Component Analysis (PCA) showed that there were two pr...

Genetic diversity and differentiation in reef-building Millepora species, as revealed by cross-species amplification of fifteen novel microsatellite loci

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Caroline E. Dubé

2017-02-01

Full Text Available Quantifying the genetic diversity in natural populations is crucial to address ecological and evolutionary questions. Despite recent advances in whole-genome sequencing, microsatellite markers have remained one of the most powerful tools for a myriad of population genetic approaches. Here, we used the 454 sequencing technique to develop microsatellite loci in the fire coral Millepora platyphylla, an important reef-builder of Indo-Pacific reefs. We tested the cross-species amplification of these loci in five other species of the genus Millepora and analysed its success in correlation with the genetic distances between species using mitochondrial 16S sequences. We succeeded in discovering fifteen microsatellite loci in our target species M. platyphylla, among which twelve were polymorphic with 2–13 alleles and a mean observed heterozygosity of 0.411. Cross-species amplification in the five other Millepora species revealed a high probability of amplification success (71% and polymorphism (59% of the loci. Our results show no evidence of decreased heterozygosity with increasing genetic distance. However, only one locus enabled measures of genetic diversity in the Caribbean species M. complanata due to high proportions of null alleles for most of the microsatellites. This result indicates that our novel markers may only be useful for the Indo-Pacific species of Millepora. Measures of genetic diversity revealed significant linkage disequilibrium, moderate levels of observed heterozygosity (0.323–0.496 and heterozygote deficiencies for the Indo-Pacific species. The accessibility to new polymorphic microsatellite markers for hydrozoan Millepora species creates new opportunities for future research on processes driving the complexity of their colonisation success on many Indo-Pacific reefs.

Comparative genomic analysis of Lactobacillus plantarum ZJ316 reveals its genetic adaptation and potential probiotic profiles.

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Li, Ping; Li, Xuan; Gu, Qing; Lou, Xiu-Yu; Zhang, Xiao-Mei; Song, Da-Feng; Zhang, Chen

2016-08-01

In previous studies, Lactobacillus plantarum ZJ316 showed probiotic properties, such as antimicrobial activity against various pathogens and the capacity to significantly improve pig growth and pork quality. The purpose of this study was to reveal the genes potentially related to its genetic adaptation and probiotic profiles based on comparative genomic analysis. The genome sequence of L. plantarum ZJ316 was compared with those of eight L. plantarum strains deposited in GenBank. BLASTN, Mauve, and MUMmer programs were used for genome alignment and comparison. CRISPRFinder was applied for searching the clustered regularly interspaced short palindromic repeats (CRISPRs). We identified genes that encode proteins related to genetic adaptation and probiotic profiles, including carbohydrate transport and metabolism, proteolytic enzyme systems and amino acid biosynthesis, CRISPR adaptive immunity, stress responses, bile salt resistance, ability to adhere to the host intestinal wall, exopolysaccharide (EPS) biosynthesis, and bacteriocin biosynthesis. Comparative characterization of the L. plantarum ZJ316 genome provided the genetic basis for further elucidating the functional mechanisms of its probiotic properties. ZJ316 could be considered a potential probiotic candidate.

Comparative genomic analysis of Lactobacillus plantarum ZJ316 reveals its genetic adaptation and potential probiotic profiles* #

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Li, Ping; Li, Xuan; Gu, Qing; Lou, Xiu-yu; Zhang, Xiao-mei; Song, Da-feng; Zhang, Chen

2016-01-01

Objective: In previous studies, Lactobacillus plantarum ZJ316 showed probiotic properties, such as antimicrobial activity against various pathogens and the capacity to significantly improve pig growth and pork quality. The purpose of this study was to reveal the genes potentially related to its genetic adaptation and probiotic profiles based on comparative genomic analysis. Methods: The genome sequence of L. plantarum ZJ316 was compared with those of eight L. plantarum strains deposited in GenBank. BLASTN, Mauve, and MUMmer programs were used for genome alignment and comparison. CRISPRFinder was applied for searching the clustered regularly interspaced short palindromic repeats (CRISPRs). Results: We identified genes that encode proteins related to genetic adaptation and probiotic profiles, including carbohydrate transport and metabolism, proteolytic enzyme systems and amino acid biosynthesis, CRISPR adaptive immunity, stress responses, bile salt resistance, ability to adhere to the host intestinal wall, exopolysaccharide (EPS) biosynthesis, and bacteriocin biosynthesis. Conclusions: Comparative characterization of the L. plantarum ZJ316 genome provided the genetic basis for further elucidating the functional mechanisms of its probiotic properties. ZJ316 could be considered a potential probiotic candidate. PMID:27487802

The Laboratory of the Dramaturge and Studies on Theatrical Genetics: experiments

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Maria de Lourdes Rabetti

2011-11-01

Full Text Available This study is situated in the field of Theatrical Genetics and deals with the presence of the dramaturge in action. It assesses the relevance and uniqueness of the process of textual migration toward the theatrical scene caused by the combined exercises of translation and dramaturgy developed between the years 1985 and 1991 by Companhia de Encenação Teatral from the city of Rio de Janeiro. It updates and comments on accumulated experiences in the creation of a number of spectacles as a result of a long and continuous creative process. Theoretically, therefore, this text aims to understand Theatrical Genetics through the eyes of the dramaturge, the theatre historian.

A Comprehensive Genomic Analysis Reveals the Genetic Landscape of Mitochondrial Respiratory Chain Complex Deficiencies.

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Masakazu Kohda

2016-01-01

Full Text Available Mitochondrial disorders have the highest incidence among congenital metabolic disorders characterized by biochemical respiratory chain complex deficiencies. It occurs at a rate of 1 in 5,000 births, and has phenotypic and genetic heterogeneity. Mutations in about 1,500 nuclear encoded mitochondrial proteins may cause mitochondrial dysfunction of energy production and mitochondrial disorders. More than 250 genes that cause mitochondrial disorders have been reported to date. However exact genetic diagnosis for patients still remained largely unknown. To reveal this heterogeneity, we performed comprehensive genomic analyses for 142 patients with childhood-onset mitochondrial respiratory chain complex deficiencies. The approach includes whole mtDNA and exome analyses using high-throughput sequencing, and chromosomal aberration analyses using high-density oligonucleotide arrays. We identified 37 novel mutations in known mitochondrial disease genes and 3 mitochondria-related genes (MRPS23, QRSL1, and PNPLA4 as novel causative genes. We also identified 2 genes known to cause monogenic diseases (MECP2 and TNNI3 and 3 chromosomal aberrations (6q24.3-q25.1, 17p12, and 22q11.21 as causes in this cohort. Our approaches enhance the ability to identify pathogenic gene mutations in patients with biochemically defined mitochondrial respiratory chain complex deficiencies in clinical settings. They also underscore clinical and genetic heterogeneity and will improve patient care of this complex disorder.

Molecular typing of canine distemper virus strains reveals the presence of a new genetic variant in South America.

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Sarute, Nicolás; Pérez, Ruben; Aldaz, Jaime; Alfieri, Amauri A; Alfieri, Alice F; Name, Daniela; Llanes, Jessika; Hernández, Martín; Francia, Lourdes; Panzera, Yanina

2014-06-01

Canine distemper virus (CDV, Paramyxoviridae, Morbillivirus) is the causative agent of a severe infectious disease affecting terrestrial and marine carnivores worldwide. Phylogenetic relationships and the genetic variability of the hemagglutinin (H) protein and the fusion protein signal-peptide (Fsp) allow for the classification of field strains into genetic lineages. Currently, there are nine CDV lineages worldwide, two of them co-circulating in South America. Using the Fsp-coding region, we analyzed the genetic variability of strains from Uruguay, Brazil, and Ecuador, and compared them with those described previously in South America and other geographical areas. The results revealed that the Brazilian and Uruguayan strains belong to the already described South America lineage (EU1/SA1), whereas the Ecuadorian strains cluster in a new clade, here named South America 3, which may represent the third CDV lineage described in South America.

Medical privacy and the disclosure of personal medical information: the beliefs and experiences of those with genetic and other clinical conditions.

Science.gov (United States)

Kass, Nancy E; Hull, Sara Chandros; Natowicz, Marvin R; Faden, Ruth R; Plantinga, Laura; Gostin, Lawrence O; Slutsman, Julia

2004-07-30

There has been heightened legislative attention to medical privacy and to protections from genetic discrimination, without large-scale studies to document privacy concerns or analysis of whether experiences differ by whether the condition is genetic (defined here as a single-gene disorder) or non-genetic. To determine whether experiences regarding privacy, disclosure, and consequences of disclosure differ by whether one's medical condition is genetic, we conducted a descriptive study with one-time, structured quantitative and qualitative interviews. We interviewed approximately 100 adults or parents of children with each of the following medical conditions: sickle cell disease, cystic fibrosis, diabetes, and HIV, and 200 adults with or at risk for breast cancer or colon cancer. The percentages of the total 597 respondents experiencing positive or negative consequences of disclosure and the degree to which experiences differed by whether the condition was genetic were the outcomes of interest. Seventy-four percent were glad and 13% regretted others knew about their condition; these findings did not differ significantly by genetic vs. non-genetic condition. Reports of job and health insurance discrimination were not uncommon for the overall study population (19 and 27%, respectively) but were more likely among those with genetic conditions (30 and 37%, respectively). Legislation and other policy-making should target the needs of persons with all conditions and not focus exclusively on genetic discrimination, given that experiences and concerns generally do not differ based on the genetic etiology of the condition. Copyright 2004 Wiley-Liss, Inc.

Genetic dissection reveals two separate retinal substrates for polarization vision in Drosophila.

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Wernet, Mathias F; Velez, Mariel M; Clark, Damon A; Baumann-Klausener, Franziska; Brown, Julian R; Klovstad, Martha; Labhart, Thomas; Clandinin, Thomas R

2012-01-10

Linearly polarized light originates from atmospheric scattering or surface reflections and is perceived by insects, spiders, cephalopods, crustaceans, and some vertebrates. Thus, the neural basis underlying how this fundamental quality of light is detected is of broad interest. Morphologically unique, polarization-sensitive ommatidia exist in the dorsal periphery of many insect retinas, forming the dorsal rim area (DRA). However, much less is known about the retinal substrates of behavioral responses to polarized reflections. Drosophila exhibits polarotactic behavior, spontaneously aligning with the e-vector of linearly polarized light, when stimuli are presented either dorsally or ventrally. By combining behavioral experiments with genetic dissection and ultrastructural analyses, we show that distinct photoreceptors mediate the two behaviors: inner photoreceptors R7+R8 of DRA ommatidia are necessary and sufficient for dorsal polarotaxis, whereas ventral responses are mediated by combinations of outer and inner photoreceptors, both of which manifest previously unknown features that render them polarization sensitive. Drosophila uses separate retinal pathways for the detection of linearly polarized light emanating from the sky or from shiny surfaces. This work establishes a behavioral paradigm that will enable genetic dissection of the circuits underlying polarization vision. Copyright © 2012 Elsevier Ltd. All rights reserved.

Teaching practice and experiences of verifying the three laws of genetics based on the SSLP marker analysis.

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Huang, Xue-Ying; Fan, Kai; Ye, Yan-Fang; Wang, Bin; Wu, Wei-Ren; Lan, Tao

2017-09-20

We explored the practical effect of the genetic analysis of simple sequence length polymorphism (SSLP) molecular markers in rice in the genetics lab course. Two parents and their F 2 population were analyzed and detected with three SSLP molecular markers that located on two chromosomes of the rice genome. The markers' genotype data were used to verify the three laws of genetics, including segregation, independent assortment and linkage and crossing-over. Our practice has proved not only beneficial to deepen students' understandings about the three laws of genetics, but also conducive to cultivate students' interests in research and innovation and improve their skills and comprehensive analysis abilities. At the same time, the application scope of the experiment was discussed. This comprehensive experiment is also useful for the transformation of scientific research achievements into undergraduate experimental teaching.

Genetic relationships among wild and cultivated accessions of curry leaf plant (Murraya koenigii (L.) Spreng.), as revealed by DNA fingerprinting methods.

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Verma, Sushma; Rana, T S

2013-02-01

Murraya koenigii (L.) Spreng. (Rutaceae), is an aromatic plant and much valued for its flavor, nutritive and medicinal properties. In this study, three DNA fingerprinting methods viz., random amplification of polymorphic DNA (RAPD), directed amplification of minisatellite DNA (DAMD), and inter-simple sequence repeat (ISSR), were used to unravel the genetic variability and relationships across 92 wild and cultivated M. koenigii accessions. A total of 310, 102, and 184, DNA fragments were amplified using 20 RAPD, 5 DAMD, and 13 ISSR primers, revealing 95.80, 96.07, and 96.73% polymorphism, respectively, across all accessions. The average polymorphic information content value obtained with RAPD, DAMD, and ISSR markers was 0.244, 0.250, and 0.281, respectively. The UPGMA tree, based on Jaccard's similarity coefficient generated from the cumulative (RAPD, DAMD, and ISSR) band data showed two distinct clusters, clearly separating wild and cultivated accessions in the dendrogram. Percentage polymorphism, gene diversity (H), and Shannon information index (I) estimates were higher in cultivated accessions compared to wild accessions. The overall high level of polymorphism and varied range of genetic distances revealed a wide genetic base in M. koenigii accessions. The study suggests that RAPD, DAMD, and ISSR markers are highly useful to unravel the genetic variability in wild and cultivated accessions of M. koenigii.

Genetic characterization of Toxoplasma gondii from Brazilian wildlife revealed abundant new genotypes.

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Vitaliano, S N; Soares, H S; Minervino, A H H; Santos, A L Q; Werther, K; Marvulo, M F V; Siqueira, D B; Pena, H F J; Soares, R M; Su, C; Gennari, S M

2014-12-01

This study aimed to isolate and genotype T. gondii from Brazilian wildlife. For this purpose, 226 samples were submitted to mice bioassay and screened by PCR based on 18S rRNA sequences. A total of 15 T. gondii isolates were obtained, including samples from four armadillos (three Dasypus novemcinctus, one Euphractus sexcinctus), three collared anteaters (Tamandua tetradactyla), three whited-lipped peccaries (Tayassu pecari), one spotted paca (Cuniculus paca), one oncilla (Leopardus tigrinus), one hoary fox (Pseudalopex vetulus), one lineated woodpecker (Dryocopus lineatus) and one maned wolf (Chrysocyon brachyurus). DNA from the isolates, originated from mice bioassay, and from the tissues of the wild animal, designated as "primary samples", were genotyped by PCR-restriction fragment length polymorphism (PCR/RFLP), using 12 genetic markers (SAG1, SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L258, PK1, CS3 and Apico). A total of 17 genotypes were identified, with 13 identified for the first time and four already reported in published literature. Results herein obtained corroborate previous studies in Brazil, confirming high diversity and revealing unique genotypes in this region. Given most of genotypes here identified are different from previous studies in domestic animals, future studies on T. gondii from wildlife is of interest to understand population genetics and structure of this parasite.

Genetic characterization of Toxoplasma gondii from Brazilian wildlife revealed abundant new genotypes

Directory of Open Access Journals (Sweden)

S.N. Vitaliano

2014-12-01

Full Text Available This study aimed to isolate and genotype T. gondii from Brazilian wildlife. For this purpose, 226 samples were submitted to mice bioassay and screened by PCR based on 18S rRNA sequences. A total of 15 T. gondii isolates were obtained, including samples from four armadillos (three Dasypus novemcinctus, one Euphractus sexcinctus, three collared anteaters (Tamandua tetradactyla, three whited-lipped peccaries (Tayassu pecari, one spotted paca (Cuniculus paca, one oncilla (Leopardus tigrinus, one hoary fox (Pseudalopex vetulus, one lineated woodpecker (Dryocopus lineatus and one maned wolf (Chrysocyon brachyurus. DNA from the isolates, originated from mice bioassay, and from the tissues of the wild animal, designated as “primary samples”, were genotyped by PCR–restriction fragment length polymorphism (PCR/RFLP, using 12 genetic markers (SAG1, SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L258, PK1, CS3 and Apico. A total of 17 genotypes were identified, with 13 identified for the first time and four already reported in published literature. Results herein obtained corroborate previous studies in Brazil, confirming high diversity and revealing unique genotypes in this region. Given most of genotypes here identified are different from previous studies in domestic animals, future studies on T. gondii from wildlife is of interest to understand population genetics and structure of this parasite.

Computational dissection of human episodic memory reveals mental process-specific genetic profiles.

Science.gov (United States)

Luksys, Gediminas; Fastenrath, Matthias; Coynel, David; Freytag, Virginie; Gschwind, Leo; Heck, Angela; Jessen, Frank; Maier, Wolfgang; Milnik, Annette; Riedel-Heller, Steffi G; Scherer, Martin; Spalek, Klara; Vogler, Christian; Wagner, Michael; Wolfsgruber, Steffen; Papassotiropoulos, Andreas; de Quervain, Dominique J-F

2015-09-01

Episodic memory performance is the result of distinct mental processes, such as learning, memory maintenance, and emotional modulation of memory strength. Such processes can be effectively dissociated using computational models. Here we performed gene set enrichment analyses of model parameters estimated from the episodic memory performance of 1,765 healthy young adults. We report robust and replicated associations of the amine compound SLC (solute-carrier) transporters gene set with the learning rate, of the collagen formation and transmembrane receptor protein tyrosine kinase activity gene sets with the modulation of memory strength by negative emotional arousal, and of the L1 cell adhesion molecule (L1CAM) interactions gene set with the repetition-based memory improvement. Furthermore, in a large functional MRI sample of 795 subjects we found that the association between L1CAM interactions and memory maintenance revealed large clusters of differences in brain activity in frontal cortical areas. Our findings provide converging evidence that distinct genetic profiles underlie specific mental processes of human episodic memory. They also provide empirical support to previous theoretical and neurobiological studies linking specific neuromodulators to the learning rate and linking neural cell adhesion molecules to memory maintenance. Furthermore, our study suggests additional memory-related genetic pathways, which may contribute to a better understanding of the neurobiology of human memory.

Computational dissection of human episodic memory reveals mental process-specific genetic profiles

Science.gov (United States)

Luksys, Gediminas; Fastenrath, Matthias; Coynel, David; Freytag, Virginie; Gschwind, Leo; Heck, Angela; Jessen, Frank; Maier, Wolfgang; Milnik, Annette; Riedel-Heller, Steffi G.; Scherer, Martin; Spalek, Klara; Vogler, Christian; Wagner, Michael; Wolfsgruber, Steffen; Papassotiropoulos, Andreas; de Quervain, Dominique J.-F.

2015-01-01

Episodic memory performance is the result of distinct mental processes, such as learning, memory maintenance, and emotional modulation of memory strength. Such processes can be effectively dissociated using computational models. Here we performed gene set enrichment analyses of model parameters estimated from the episodic memory performance of 1,765 healthy young adults. We report robust and replicated associations of the amine compound SLC (solute-carrier) transporters gene set with the learning rate, of the collagen formation and transmembrane receptor protein tyrosine kinase activity gene sets with the modulation of memory strength by negative emotional arousal, and of the L1 cell adhesion molecule (L1CAM) interactions gene set with the repetition-based memory improvement. Furthermore, in a large functional MRI sample of 795 subjects we found that the association between L1CAM interactions and memory maintenance revealed large clusters of differences in brain activity in frontal cortical areas. Our findings provide converging evidence that distinct genetic profiles underlie specific mental processes of human episodic memory. They also provide empirical support to previous theoretical and neurobiological studies linking specific neuromodulators to the learning rate and linking neural cell adhesion molecules to memory maintenance. Furthermore, our study suggests additional memory-related genetic pathways, which may contribute to a better understanding of the neurobiology of human memory. PMID:26261317

Genetic relationship among Musa genotypes revealed by ...

African Journals Online (AJOL)

enoh

2012-03-29

Mar 29, 2012 ... A banana germplasm was established containing 44 Musa genotypes collected from various locations in Malaysia. To detect their genetic variation and to rule out duplicates among cultivar, microsatellite markers were used in their analysis. The microsatellite profiles of 44 Musa genotypes of various origins.

Differential network analysis reveals genetic effects on catalepsy modules.

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Ovidiu D Iancu

Full Text Available We performed short-term bi-directional selective breeding for haloperidol-induced catalepsy, starting from three mouse populations of increasingly complex genetic structure: an F2 intercross, a heterogeneous stock (HS formed by crossing four inbred strains (HS4 and a heterogeneous stock (HS-CC formed from the inbred strain founders of the Collaborative Cross (CC. All three selections were successful, with large differences in haloperidol response emerging within three generations. Using a custom differential network analysis procedure, we found that gene coexpression patterns changed significantly; importantly, a number of these changes were concordant across genetic backgrounds. In contrast, absolute gene-expression changes were modest and not concordant across genetic backgrounds, in spite of the large and similar phenotypic differences. By inferring strain contributions from the parental lines, we are able to identify significant differences in allelic content between the selected lines concurrent with large changes in transcript connectivity. Importantly, this observation implies that genetic polymorphisms can affect transcript and module connectivity without large changes in absolute expression levels. We conclude that, in this case, selective breeding acts at the subnetwork level, with the same modules but not the same transcripts affected across the three selections.

Alu polymorphic insertions reveal genetic structure of north Indian populations.

Science.gov (United States)

Tripathi, Manorama; Tripathi, Piyush; Chauhan, Ugam Kumari; Herrera, Rene J; Agrawal, Suraksha

2008-10-01

The Indian subcontinent is characterized by the ancestral and cultural diversity of its people. Genetic input from several unique source populations and from the unique social architecture provided by the caste system has shaped the current genetic landscape of India. In the present study 200 individuals each from three upper-caste and four middle-caste Hindu groups and from two Muslim populations in North India were examined for 10 polymorphic Alu insertions (PAIs). The investigated PAIs exhibit high levels of polymorphism and average heterozygosity. Limited interpopulation variance and genetic flow in the present study suggest admixture. The results of this study demonstrate that, contrary to common belief, the caste system has not provided an impermeable barrier to genetic exchange among Indian groups.

Spatial genetic analyses reveal cryptic population structure and migration patterns in a continuously harvested grey wolf (Canis lupus population in north-eastern Europe.

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Maris Hindrikson

Full Text Available Spatial genetics is a relatively new field in wildlife and conservation biology that is becoming an essential tool for unravelling the complexities of animal population processes, and for designing effective strategies for conservation and management. Conceptual and methodological developments in this field are therefore critical. Here we present two novel methodological approaches that further the analytical possibilities of STRUCTURE and DResD. Using these approaches we analyse structure and migrations in a grey wolf (Canislupus population in north-eastern Europe. We genotyped 16 microsatellite loci in 166 individuals sampled from the wolf population in Estonia and Latvia that has been under strong and continuous hunting pressure for decades. Our analysis demonstrated that this relatively small wolf population is represented by four genetic groups. We also used a novel methodological approach that uses linear interpolation to statistically test the spatial separation of genetic groups. The new method, which is capable of using program STRUCTURE output, can be applied widely in population genetics to reveal both core areas and areas of low significance for genetic groups. We also used a recently developed spatially explicit individual-based method DResD, and applied it for the first time to microsatellite data, revealing a migration corridor and barriers, and several contact zones.

Genomic view of bipolar disorder revealed by whole genome sequencing in a genetic isolate.

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Benjamin Georgi

2014-03-01

Full Text Available Bipolar disorder is a common, heritable mental illness characterized by recurrent episodes of mania and depression. Despite considerable effort to elucidate the genetic underpinnings of bipolar disorder, causative genetic risk factors remain elusive. We conducted a comprehensive genomic analysis of bipolar disorder in a large Old Order Amish pedigree. Microsatellite genotypes and high-density SNP-array genotypes of 388 family members were combined with whole genome sequence data for 50 of these subjects, comprising 18 parent-child trios. This study design permitted evaluation of candidate variants within the context of haplotype structure by resolving the phase in sequenced parent-child trios and by imputation of variants into multiple unsequenced siblings. Non-parametric and parametric linkage analysis of the entire pedigree as well as on smaller clusters of families identified several nominally significant linkage peaks, each of which included dozens of predicted deleterious variants. Close inspection of exonic and regulatory variants in genes under the linkage peaks using family-based association tests revealed additional credible candidate genes for functional studies and further replication in population-based cohorts. However, despite the in-depth genomic characterization of this unique, large and multigenerational pedigree from a genetic isolate, there was no convergence of evidence implicating a particular set of risk loci or common pathways. The striking haplotype and locus heterogeneity we observed has profound implications for the design of studies of bipolar and other related disorders.

Genomic View of Bipolar Disorder Revealed by Whole Genome Sequencing in a Genetic Isolate

Science.gov (United States)

Georgi, Benjamin; Craig, David; Kember, Rachel L.; Liu, Wencheng; Lindquist, Ingrid; Nasser, Sara; Brown, Christopher; Egeland, Janice A.; Paul, Steven M.; Bućan, Maja

2014-01-01

Bipolar disorder is a common, heritable mental illness characterized by recurrent episodes of mania and depression. Despite considerable effort to elucidate the genetic underpinnings of bipolar disorder, causative genetic risk factors remain elusive. We conducted a comprehensive genomic analysis of bipolar disorder in a large Old Order Amish pedigree. Microsatellite genotypes and high-density SNP-array genotypes of 388 family members were combined with whole genome sequence data for 50 of these subjects, comprising 18 parent-child trios. This study design permitted evaluation of candidate variants within the context of haplotype structure by resolving the phase in sequenced parent-child trios and by imputation of variants into multiple unsequenced siblings. Non-parametric and parametric linkage analysis of the entire pedigree as well as on smaller clusters of families identified several nominally significant linkage peaks, each of which included dozens of predicted deleterious variants. Close inspection of exonic and regulatory variants in genes under the linkage peaks using family-based association tests revealed additional credible candidate genes for functional studies and further replication in population-based cohorts. However, despite the in-depth genomic characterization of this unique, large and multigenerational pedigree from a genetic isolate, there was no convergence of evidence implicating a particular set of risk loci or common pathways. The striking haplotype and locus heterogeneity we observed has profound implications for the design of studies of bipolar and other related disorders. PMID:24625924

Complete genomes reveal signatures of demographic and genetic declines in the woolly mammoth

Science.gov (United States)

Palkopoulou, Eleftheria; Mallick, Swapan; Skoglund, Pontus; Enk, Jacob; Rohland, Nadin; Li, Heng; Omrak, Ayça; Vartanyan, Sergey; Poinar, Hendrik; Götherström, Anders; Reich, David; Dalén, Love

2015-01-01

Summary The processes leading up to species extinctions are typically characterized by prolonged declines in population size and geographic distribution, followed by a phase in which populations are very small and may be subject to intrinsic threats, including loss of genetic diversity and inbreeding [1]. However, whether such genetic factors have had an impact on species prior to their extinction is unclear [2, 3]; examining this would require a detailed reconstruction of a species’ demographic history as well as changes in genome-wide diversity leading up to its extinction. Here, we present high-quality complete genome sequences from two woolly mammoths (Mammuthus primigenius). The first mammoth was sequenced at 17.1-fold coverage, and dates to ~4,300 years before present, constituting one of the last surviving individuals on Wrangel Island. The second mammoth, sequenced at 11.2-fold coverage, was obtained from a ~44,800 year old specimen from the Late Pleistocene population in northeastern Siberia. The demographic trajectories inferred from the two genomes are qualitatively similar and reveal a population bottleneck during the Middle or Early Pleistocene, and a more recent severe decline in the ancestors of the Wrangel mammoth at the end of the last glaciation. A comparison of the two genomes shows that the Wrangel mammoth has a 20% reduction in heterozygosity as well as a 28-fold increase in the fraction of the genome that is comprised of runs of homozygosity. We conclude that the population on Wrangel Island, which was the last surviving woolly mammoth population, was subject to reduced genetic diversity shortly before it became extinct. PMID:25913407

Genetic variation in Rhodomyrtus tomentosa (Kemunting) populations from Malaysia as revealed by inter-simple sequence repeat markers.

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Hue, T S; Abdullah, T L; Abdullah, N A P; Sinniah, U R

2015-12-14

Kemunting (Rhodomyrtus tomentosa) from the Myrtaceae family, is native to Malaysia. It is widely used in traditional medicine to treat various illnesses and possesses significant antibacterial properties. In addition, it has great potential as ornamental in landscape design. Genetic variability studies are important for the rational management and conservation of genetic material. In the present study, inter-simple sequence repeat markers were used to assess the genetic diversity of 18 R. tomentosa populations collected from ten states of Peninsular Malaysia. The 11 primers selected generated 173 bands that ranged in size from 1.6 kb to 130 bp, which corresponded to an average of 15.73 bands per primer. Of these bands, 97.69% (169 in total) were polymorphic. High genetic diversity was documented at the species level (H(T) = 0.2705; I = 0.3973; PPB = 97.69%) but there was a low diversity at population level (H(S) = 0.0073; I = 0 .1085; PPB = 20.14%). The high level of genetic differentiation revealed by G(ST) (73%) and analysis of molecular variance (63%), together with the limited gene flow among population (N(m) = 0.1851), suggests that the populations examined are isolated. Results from an unweighted pair group method with arithmetic mean dendrogram and principal coordinate analysis clearly grouped the populations into two geographic groups. This clear grouping can also be demonstrated by the significant Mantel test (r = 0.581, P = 0.001). We recommend that all the R. tomentosa populations be preserved in conservation program.

A replicated climate change field experiment reveals rapid evolutionary response in an ecologically important soil invertebrate

DEFF Research Database (Denmark)

Bataillon, Thomas; Galtier, Nicolas; Bernard, Aurelien

2016-01-01

to climate change in a common annelid worm using a controlled replicated experiment where climatic conditions were manipulated in a natural setting. Analyzing the transcribed genome of 15 local populations, we found that about 12% of the genetic polymorphisms exhibit differences in allele frequencies......Whether species can respond evolutionarily to current climate change is crucial for the persistence of many species. Yet, very few studies have examined genetic responses to climate change in manipulated experiments carried out innatural field conditions. We examined the evolutionary response...... associated to changes in soil temperature and soil moisture. This shows an evolutionaryresponse to realistic climate change happening over short-time scale, and calls for incorporating evolution into modelspredicting future response of species to climate change. It also shows that designed climate change...

Genetic technologies for extremely thermophilic microorganisms of Sulfolobus, the only genetically tractable genus of crenarchaea.

Science.gov (United States)

Peng, Nan; Han, Wenyuan; Li, Yingjun; Liang, Yunxiang; She, Qunxin

2017-04-01

Archaea represents the third domain of life, with the information-processing machineries more closely resembling those of eukaryotes than the machineries of the bacterial counterparts but sharing metabolic pathways with organisms of Bacteria, the sister prokaryotic phylum. Archaeal organisms also possess unique features as revealed by genomics and genome comparisons and by biochemical characterization of prominent enzymes. Nevertheless, diverse genetic tools are required for in vivo experiments to verify these interesting discoveries. Considerable efforts have been devoted to the development of genetic tools for archaea ever since their discovery, and great progress has been made in the creation of archaeal genetic tools in the past decade. Versatile genetic toolboxes are now available for several archaeal models, among which Sulfolobus microorganisms are the only genus representing Crenarchaeota because all the remaining genera are from Euryarchaeota. Nevertheless, genetic tools developed for Sulfolobus are probably the most versatile among all archaeal models, and these include viral and plasmid shuttle vectors, conventional and novel genetic manipulation methods, CRISPR-based gene deletion and mutagenesis, and gene silencing, among which CRISPR tools have been reported only for Sulfolobus thus far. In this review, we summarize recent developments in all these useful genetic tools and discuss their possible application to research into archaeal biology by means of Sulfolobus models.

Start Codon Targeted (SCoT) marker reveals genetic diversity of Dendrobium nobile Lindl., an endangered medicinal orchid species.

Science.gov (United States)

Bhattacharyya, Paromik; Kumaria, Suman; Kumar, Shrawan; Tandon, Pramod

2013-10-15

Genetic variability in the wild genotypes of Dendrobium nobile Lindl. collected from different parts of Northeast India, was analyzed using a Start Codon Targeted (SCoT) marker system. A total of sixty individuals comprising of six natural populations were investigated for the existing natural genetic diversity. One hundred and thirty two (132) amplicons were produced by SCoT marker generating 96.21% polymorphism. The PIC value of the SCoT marker system was 0.78 and the Rp values of the primers ranged between 4.43 and 7.50. The percentage of polymorphic loci (Pp) ranging from 25% to 56.82%, Nei's gene diversity (h) from 0.08 to 0.15 with mean Nei's gene diversity of 0.28, and Shannon's information index (I) values ranging from 0.13 to 0.24 with an average value of 0.43 were recorded. The gene flow value (0.37) and the diversity among populations (0.57) demonstrated higher genetic variation among the populations. Analysis of molecular variance (AMOVA) showed 43.37% of variation within the populations, whereas 56.63% variation was recorded among the populations. Cluster analysis also reveals high genetic variation among the genotypes. Present investigation suggests the effectiveness of SCoT marker system to estimate the genetic diversity of D. nobile and that it can be seen as a preliminary point for future research on the population and evolutionary genetics of this endangered orchid species of medicinal importance. © 2013.

Genetic regulation of salt stress tolerance revealed by RNA-Seq in cotton diploid wild species, Gossypium davidsonii.

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Zhang, Feng; Zhu, Guozhong; Du, Lei; Shang, Xiaoguang; Cheng, Chaoze; Yang, Bing; Hu, Yan; Cai, Caiping; Guo, Wangzhen

2016-02-03

Cotton is an economically important crop throughout the world, and is a pioneer crop in salt stress tolerance research. Investigation of the genetic regulation of salinity tolerance will provide information for salt stress-resistant breeding. Here, we employed next-generation RNA-Seq technology to elucidate the salt-tolerant mechanisms in cotton using the diploid cotton species Gossypium davidsonii which has superior stress tolerance. A total of 4744 and 5337 differentially expressed genes (DEGs) were found to be involved in salt stress tolerance in roots and leaves, respectively. Gene function annotation elucidated salt overly sensitive (SOS) and reactive oxygen species (ROS) signaling pathways. Furthermore, we found that photosynthesis pathways and metabolism play important roles in ion homeostasis and oxidation balance. Moreover, our studies revealed that alternative splicing also contributes to salt-stress responses at the posttranscriptional level, implying its functional role in response to salinity stress. This study not only provides a valuable resource for understanding the genetic control of salt stress in cotton, but also lays a substantial foundation for the genetic improvement of crop resistance to salt stress.

The alliance between genetic biobanks and patient organisations: the experience of the telethon network of genetic biobanks.

Science.gov (United States)

Baldo, Chiara; Casareto, Lorena; Renieri, Alessandra; Merla, Giuseppe; Garavaglia, Barbara; Goldwurm, Stefano; Pegoraro, Elena; Moggio, Maurizio; Mora, Marina; Politano, Luisa; Sangiorgi, Luca; Mazzotti, Raffaella; Viotti, Valeria; Meloni, Ilaria; Pellico, Maria Teresa; Barzaghi, Chiara; Wang, Chiuhui Mary; Monaco, Lucia; Filocamo, Mirella

2016-10-24

Rare diseases (RDs) are often neglected because they affect a small percentage of the population (6-8 %), which makes research and development of new therapies challenging processes. Easy access to high-quality samples and associated clinical data is therefore a key prerequisite for biomedical research. In this context, Genetic Biobanks are critical to developing basic, translational and clinical research on RDs. The Telethon Network of Genetic Biobanks (TNGB) is aware of the importance of biobanking as a service for patients and has started a dialogue with RD-Patient Organisations via promotion of dedicated meetings and round-tables, as well as by including their representatives on the TNGB Advisory Board. This has enabled the active involvement of POs in drafting biobank policies and procedures, including those concerning ethical issues. Here, we report on our experience with RD-Patient Organisations who have requested the services of existing biobanks belonging to TNGB and describe how these relationships were established, formalised and maintained. The process of patient engagement has proven to be successful both for lay members, who increased their understanding of the complex processes of biobanking, and for professionals, who gained awareness of the needs and expectations of the people involved. This collaboration has resulted in a real interest on the part of Patient Organisations in the biobanking service, which has led to 13 written agreements designed to formalise this process. These agreements enabled the centralisation of rare genetic disease biospecimens and their related data, thus making them available to the scientific community. The TNGB experience has proven to be an example of good practice with regard to patient engagement in biobanking and may serve as a model of collaboration between disease-oriented Biobanks and Patient Organisations. Such collaboration serves to enhance awareness and trust and to encourage the scientific community to

Systems Genetics Reveals the Functional Context of PCOS Loci and Identifies Genetic and Molecular Mechanisms of Disease Heterogeneity

Science.gov (United States)

Xu, Ning; Cui, Jinrui; Mengesha, Emebet; Chen, Yii-Der I.; Taylor, Kent D.; Azziz, Ricardo; Goodarzi, Mark O.

2015-01-01

Genome wide association studies (GWAS) have revealed 11 independent risk loci for polycystic ovary syndrome (PCOS), a common disorder in young women characterized by androgen excess and oligomenorrhea. To put these risk loci and the single nucleotide polymorphisms (SNPs) therein into functional context, we measured DNA methylation and gene expression in subcutaneous adipose tissue biopsies to identify PCOS-specific alterations. Two genes from the LHCGR region, STON1-GTF2A1L and LHCGR, were overexpressed in PCOS. In analysis stratified by obesity, LHCGR was overexpressed only in non-obese PCOS women. Although not differentially expressed in the entire PCOS group, INSR was underexpressed in obese PCOS subjects only. Alterations in gene expression in the LHCGR, RAB5B and INSR regions suggest that SNPs in these loci may be functional and could affect gene expression directly or indirectly via epigenetic alterations. We identified reduced methylation in the LHCGR locus and increased methylation in the INSR locus, changes that are concordant with the altered gene expression profiles. Complex patterns of meQTL and eQTL were identified in these loci, suggesting that local genetic variation plays an important role in gene regulation. We propose that non-obese PCOS women possess significant alterations in LH receptor expression, which drives excess androgen secretion from the ovary. Alternatively, obese women with PCOS possess alterations in insulin receptor expression, with underexpression in metabolic tissues and overexpression in the ovary, resulting in peripheral insulin resistance and excess ovarian androgen production. These studies provide a genetic and molecular basis for the reported clinical heterogeneity of PCOS. PMID:26305227

Systems Genetics Reveals the Functional Context of PCOS Loci and Identifies Genetic and Molecular Mechanisms of Disease Heterogeneity.

Science.gov (United States)

Jones, Michelle R; Brower, Meredith A; Xu, Ning; Cui, Jinrui; Mengesha, Emebet; Chen, Yii-Der I; Taylor, Kent D; Azziz, Ricardo; Goodarzi, Mark O

2015-08-01

Genome wide association studies (GWAS) have revealed 11 independent risk loci for polycystic ovary syndrome (PCOS), a common disorder in young women characterized by androgen excess and oligomenorrhea. To put these risk loci and the single nucleotide polymorphisms (SNPs) therein into functional context, we measured DNA methylation and gene expression in subcutaneous adipose tissue biopsies to identify PCOS-specific alterations. Two genes from the LHCGR region, STON1-GTF2A1L and LHCGR, were overexpressed in PCOS. In analysis stratified by obesity, LHCGR was overexpressed only in non-obese PCOS women. Although not differentially expressed in the entire PCOS group, INSR was underexpressed in obese PCOS subjects only. Alterations in gene expression in the LHCGR, RAB5B and INSR regions suggest that SNPs in these loci may be functional and could affect gene expression directly or indirectly via epigenetic alterations. We identified reduced methylation in the LHCGR locus and increased methylation in the INSR locus, changes that are concordant with the altered gene expression profiles. Complex patterns of meQTL and eQTL were identified in these loci, suggesting that local genetic variation plays an important role in gene regulation. We propose that non-obese PCOS women possess significant alterations in LH receptor expression, which drives excess androgen secretion from the ovary. Alternatively, obese women with PCOS possess alterations in insulin receptor expression, with underexpression in metabolic tissues and overexpression in the ovary, resulting in peripheral insulin resistance and excess ovarian androgen production. These studies provide a genetic and molecular basis for the reported clinical heterogeneity of PCOS.

Quantitative genome-wide genetic interaction screens reveal global epistatic relationships of protein complexes in Escherichia coli.

Directory of Open Access Journals (Sweden)

Mohan Babu

2014-02-01

Full Text Available Large-scale proteomic analyses in Escherichia coli have documented the composition and physical relationships of multiprotein complexes, but not their functional organization into biological pathways and processes. Conversely, genetic interaction (GI screens can provide insights into the biological role(s of individual gene and higher order associations. Combining the information from both approaches should elucidate how complexes and pathways intersect functionally at a systems level. However, such integrative analysis has been hindered due to the lack of relevant GI data. Here we present a systematic, unbiased, and quantitative synthetic genetic array screen in E. coli describing the genetic dependencies and functional cross-talk among over 600,000 digenic mutant combinations. Combining this epistasis information with putative functional modules derived from previous proteomic data and genomic context-based methods revealed unexpected associations, including new components required for the biogenesis of iron-sulphur and ribosome integrity, and the interplay between molecular chaperones and proteases. We find that functionally-linked genes co-conserved among γ-proteobacteria are far more likely to have correlated GI profiles than genes with divergent patterns of evolution. Overall, examining bacterial GIs in the context of protein complexes provides avenues for a deeper mechanistic understanding of core microbial systems.

Genomewide mapping reveals a combination of different genetic ...

Indian Academy of Sciences (India)

could not investigate all kinds of genetic effects, especially epistatic effects, simultaneously on the whole genome. ... consistent with different loci affecting heterosis for different ...... Jones D. F. 1917 Dominance of linked factors as a means of.

Pathophysiological Significance of Dermatan Sulfate Proteoglycans Revealed by Human Genetic Disorders

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Shuji Mizumoto

2017-03-01

Full Text Available The indispensable roles of dermatan sulfate-proteoglycans (DS-PGs have been demonstrated in various biological events including construction of the extracellular matrix and cell signaling through interactions with collagen and transforming growth factor-β, respectively. Defects in the core proteins of DS-PGs such as decorin and biglycan cause congenital stromal dystrophy of the cornea, spondyloepimetaphyseal dysplasia, and Meester-Loeys syndrome. Furthermore, mutations in human genes encoding the glycosyltransferases, epimerases, and sulfotransferases responsible for the biosynthesis of DS chains cause connective tissue disorders including Ehlers-Danlos syndrome and spondyloepimetaphyseal dysplasia with joint laxity characterized by skin hyperextensibility, joint hypermobility, and tissue fragility, and by severe skeletal disorders such as kyphoscoliosis, short trunk, dislocation, and joint laxity. Glycobiological approaches revealed that mutations in DS-biosynthetic enzymes cause reductions in enzymatic activities and in the amount of synthesized DS and also disrupt the formation of collagen bundles. This review focused on the growing number of glycobiological studies on recently reported genetic diseases caused by defects in the biosynthesis of DS and DS-PGs.

Approximate Quantum Adders with Genetic Algorithms: An IBM Quantum Experience

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Li Rui

2017-07-01

Full Text Available It has been proven that quantum adders are forbidden by the laws of quantum mechanics. We analyze theoretical proposals for the implementation of approximate quantum adders and optimize them by means of genetic algorithms, improving previous protocols in terms of efficiency and fidelity. Furthermore, we experimentally realize a suitable approximate quantum adder with the cloud quantum computing facilities provided by IBM Quantum Experience. The development of approximate quantum adders enhances the toolbox of quantum information protocols, paving the way for novel applications in quantum technologies.

Partitioning the heritability of Tourette syndrome and obsessive compulsive disorder reveals differences in genetic architecture.

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Lea K Davis

2013-10-01

Full Text Available The direct estimation of heritability from genome-wide common variant data as implemented in the program Genome-wide Complex Trait Analysis (GCTA has provided a means to quantify heritability attributable to all interrogated variants. We have quantified the variance in liability to disease explained by all SNPs for two phenotypically-related neurobehavioral disorders, obsessive-compulsive disorder (OCD and Tourette Syndrome (TS, using GCTA. Our analysis yielded a heritability point estimate of 0.58 (se = 0.09, p = 5.64e-12 for TS, and 0.37 (se = 0.07, p = 1.5e-07 for OCD. In addition, we conducted multiple genomic partitioning analyses to identify genomic elements that concentrate this heritability. We examined genomic architectures of TS and OCD by chromosome, MAF bin, and functional annotations. In addition, we assessed heritability for early onset and adult onset OCD. Among other notable results, we found that SNPs with a minor allele frequency of less than 5% accounted for 21% of the TS heritability and 0% of the OCD heritability. Additionally, we identified a significant contribution to TS and OCD heritability by variants significantly associated with gene expression in two regions of the brain (parietal cortex and cerebellum for which we had available expression quantitative trait loci (eQTLs. Finally we analyzed the genetic correlation between TS and OCD, revealing a genetic correlation of 0.41 (se = 0.15, p = 0.002. These results are very close to previous heritability estimates for TS and OCD based on twin and family studies, suggesting that very little, if any, heritability is truly missing (i.e., unassayed from TS and OCD GWAS studies of common variation. The results also indicate that there is some genetic overlap between these two phenotypically-related neuropsychiatric disorders, but suggest that the two disorders have distinct genetic architectures.

Rangewide genetic analysis of Lesser Prairie-Chicken reveals population structure, range expansion, and possible introgression

Science.gov (United States)

Oyler-McCance, Sara J.; DeYoung, Randall W; Fike, Jennifer; Hagen, Christian A.; Johnson, Jeff A.; Larsson, Lena C.; Patten, Michael

2016-01-01

The distribution of the Lesser Prairie-Chicken (Tympanuchus pallidicinctus) has been markedly reduced due to loss and fragmentation of habitat. Portions of the historical range, however, have been recolonized and even expanded due to planting of conservation reserve program (CRP) fields that provide favorable vegetation structure for Lesser Prairie-Chickens. The source population(s) feeding the range expansion is unknown, yet has resulted in overlap between Lesser and Greater Prairie-Chickens (T. cupido) increasing the potential for hybridization. Our objectives were to characterize connectivity and genetic diversity among populations, identify source population(s) of recent range expansion, and examine hybridization with the Greater Prairie-Chicken. We analyzed 640 samples from across the range using 13 microsatellites. We identified three to four populations corresponding largely to ecoregions. The Shinnery Oak Prairie and Sand Sagebrush Prairie represented genetically distinct populations (F ST > 0.034 and F ST > 0.023 respectively). The Shortgrass/CRP Mosaic and Mixed Grass ecoregions appeared admixed (F ST = 0.009). Genetic diversity was similar among ecoregions and N e ranged from 142 (95 % CI 99–236) for the Shortgrass/CRP Mosaic to 296 (95 % CI 233–396) in the Mixed Grass Prairie. No recent migration was detected among ecoregions, except asymmetric dispersal from both the Mixed Grass Prairie and to a lesser extent the Sand Sagebrush Prairie north into adjacent Shortgrass/CRP Mosaic (m = 0.207, 95 % CI 0.116–0.298, m = 0.097, 95 % CI 0.010–0.183, respectively). Indices investigating potential hybridization in the Shortgrass/CRP Mosaic revealed that six of the 13 individuals with hybrid phenotypes were significantly admixed suggesting hybridization. Continued monitoring of diversity within and among ecoregions is warranted as are actions promoting genetic connectivity and range expansion.

Random amplified polymorphic DNA (RAPD) markers reveal genetic ...

African Journals Online (AJOL)

The present study evaluated genetic variability of superior bael genotypes collected from different parts of Andaman Islands, India using fruit characters and random amplified polymorphic DNA (RAPD) markers. Genomic DNA extracted from leaf material using cetyl trimethyl ammonium bromide (CTAB) method was ...

Eliciting preferences for priority setting in genetic testing: a pilot study comparing best-worst scaling and discrete-choice experiments.

Science.gov (United States)

Severin, Franziska; Schmidtke, Jörg; Mühlbacher, Axel; Rogowski, Wolf H

2013-11-01

Given the increasing number of genetic tests available, decisions have to be made on how to allocate limited health-care resources to them. Different criteria have been proposed to guide priority setting. However, their relative importance is unclear. Discrete-choice experiments (DCEs) and best-worst scaling experiments (BWSs) are methods used to identify and weight various criteria that influence orders of priority. This study tests whether these preference eliciting techniques can be used for prioritising genetic tests and compares the empirical findings resulting from these two approaches. Pilot DCE and BWS questionnaires were developed for the same criteria: prevalence, severity, clinical utility, alternatives to genetic testing available, infrastructure for testing and care established, and urgency of care. Interview-style experiments were carried out among different genetics professionals (mainly clinical geneticists, researchers and biologists). A total of 31 respondents completed the DCE and 26 completed the BWS experiment. Weights for the levels of the six attributes were estimated by conditional logit models. Although the results derived from the DCE and BWS experiments differed in detail, we found similar valuation patterns in the DCE and BWS experiments. The respondents attached greatest value to tests with high clinical utility (defined by the availability of treatments that reduce mortality and morbidity) and to testing for highly prevalent conditions. The findings from this study exemplify how decision makers can use quantitative preference eliciting methods to measure aggregated preferences in order to prioritise alternative clinical interventions. Further research is necessary to confirm the survey results.

The alliance between genetic biobanks and patient organisations: the experience of the telethon network of genetic biobanks

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Chiara Baldo

2016-10-01

Full Text Available Abstract Background Rare diseases (RDs are often neglected because they affect a small percentage of the population (6–8 %, which makes research and development of new therapies challenging processes. Easy access to high-quality samples and associated clinical data is therefore a key prerequisite for biomedical research. In this context, Genetic Biobanks are critical to developing basic, translational and clinical research on RDs. The Telethon Network of Genetic Biobanks (TNGB is aware of the importance of biobanking as a service for patients and has started a dialogue with RD-Patient Organisations via promotion of dedicated meetings and round-tables, as well as by including their representatives on the TNGB Advisory Board. This has enabled the active involvement of POs in drafting biobank policies and procedures, including those concerning ethical issues. Here, we report on our experience with RD-Patient Organisations who have requested the services of existing biobanks belonging to TNGB and describe how these relationships were established, formalised and maintained. Results The process of patient engagement has proven to be successful both for lay members, who increased their understanding of the complex processes of biobanking, and for professionals, who gained awareness of the needs and expectations of the people involved. This collaboration has resulted in a real interest on the part of Patient Organisations in the biobanking service, which has led to 13 written agreements designed to formalise this process. These agreements enabled the centralisation of rare genetic disease biospecimens and their related data, thus making them available to the scientific community. Conclusions The TNGB experience has proven to be an example of good practice with regard to patient engagement in biobanking and may serve as a model of collaboration between disease-oriented Biobanks and Patient Organisations. Such collaboration serves to enhance awareness

Systems Genetics Reveals the Functional Context of PCOS Loci and Identifies Genetic and Molecular Mechanisms of Disease Heterogeneity.

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Michelle R Jones

2015-08-01

Full Text Available Genome wide association studies (GWAS have revealed 11 independent risk loci for polycystic ovary syndrome (PCOS, a common disorder in young women characterized by androgen excess and oligomenorrhea. To put these risk loci and the single nucleotide polymorphisms (SNPs therein into functional context, we measured DNA methylation and gene expression in subcutaneous adipose tissue biopsies to identify PCOS-specific alterations. Two genes from the LHCGR region, STON1-GTF2A1L and LHCGR, were overexpressed in PCOS. In analysis stratified by obesity, LHCGR was overexpressed only in non-obese PCOS women. Although not differentially expressed in the entire PCOS group, INSR was underexpressed in obese PCOS subjects only. Alterations in gene expression in the LHCGR, RAB5B and INSR regions suggest that SNPs in these loci may be functional and could affect gene expression directly or indirectly via epigenetic alterations. We identified reduced methylation in the LHCGR locus and increased methylation in the INSR locus, changes that are concordant with the altered gene expression profiles. Complex patterns of meQTL and eQTL were identified in these loci, suggesting that local genetic variation plays an important role in gene regulation. We propose that non-obese PCOS women possess significant alterations in LH receptor expression, which drives excess androgen secretion from the ovary. Alternatively, obese women with PCOS possess alterations in insulin receptor expression, with underexpression in metabolic tissues and overexpression in the ovary, resulting in peripheral insulin resistance and excess ovarian androgen production. These studies provide a genetic and molecular basis for the reported clinical heterogeneity of PCOS.

Genetic and Environmental Basis of the Relationship Between Dissociative Experiences and Cloninger’s Temperament and Character Dimensions – Pilot Study

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Domozych Wojciech

2016-12-01

Full Text Available Dissociation is commonly regarded as a disruption in the normally integrated functions of memory, knowledge, affect, sensation or behavior. The present study utilized behavioral genetics’ methodology to investigate genetic and environmental basis of the relationship between dissociation and Cloninger’s temperament and character traits. A sample of 83 monozygotic and 65 dizygotic twins were administered self-report measures which assessed dissociative experiences along with personality dimensions. Significant correlations and high loads of common genetic variance between dissociative experiences and personality traits of novelty seeking, self-directedness, cooperativeness and self-transcendence were identified. Heritability of dissociative experiences was estimated at 62%. The study shows that there exists a considerable amount of genetic variance overlap between dissociation and personality dimensions. It also supports the hypothesis that propensity to dissociate is highly heritable

Perception, experience, and response to genetic discrimination in Huntington's disease: the Australian results of The International RESPOND-HD study.

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Goh, Anita M Y; Chiu, Edmond; Yastrubetskaya, Olga; Erwin, Cheryl; Williams, Janet K; Juhl, Andrew R; Paulsen, Jane S

2013-02-01

This study examines elements of genetic discrimination among an at-risk, clinically undiagnosed Huntington's disease (HD) population. Sixty at-risk individuals, either positive or negative for the HD genetic mutation, completed a survey regarding their experiences of genetic discrimination, adverse and unfair treatment, and knowledge about existing laws and policies surrounding genetic discrimination. Sixty eight percent of participants reported feeling "Great benefit" from knowing their genetic test results. Reported benefits of knowledge included planning for the future, making decisions, and many individuals found meaning in active participation in the HD community and in advocating for themselves or families at risk for HD. Many individuals found personal meaning and a sense of community from knowledge of this information and from the ability to participate in research. Despite these positive feelings toward gene testing, results demonstrated that 33% of participants perceived experiences of genetic discrimination, which occurred repeatedly and caused great self-reported distress. Significantly, more gene-positive respondents reported experiencing incidents of genetic discrimination, compared to gene-negative respondents. At least 58 separate incidents of discrimination were reported, the number of incidents ranged from 1 to 10, with 45% of individuals (9/20 respondents) indicating more than one event. Of the most significant events of discrimination, 58% were related to insurance, 21% to employment, 16% to transactions of daily life, and 5% to relationships. Results contribute toward validation of empirical data regarding genetic discrimination.

Genetic relationships between clinical and non-clinical strains of Yersinia enterocolitica biovar 1A as revealed by multilocus enzyme electrophoresis and multilocus restriction typing

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Virdi Jugsharan S

2010-05-01

Full Text Available Abstract Background Genetic relationships among 81 strains of Y. enterocolitica biovar 1A isolated from clinical and non-clinical sources were discerned by multilocus enzyme electrophoresis (MLEE and multilocus restriction typing (MLRT using six loci each. Such studies may reveal associations between the genotypes of the strains and their sources of isolation. Results All loci were polymorphic and generated 62 electrophoretic types (ETs and 12 restriction types (RTs. The mean genetic diversity (H of the strains by MLEE and MLRT was 0.566 and 0.441 respectively. MLEE (DI = 0.98 was more discriminatory and clustered Y. enterocolitica biovar 1A strains into four groups, while MLRT (DI = 0.77 identified two distinct groups. BURST (Based Upon Related Sequence Types analysis of the MLRT data suggested aquatic serotype O:6,30-6,31 isolates to be the ancestral strains from which, clinical O:6,30-6,31 strains might have originated by host adaptation and genetic change. Conclusion MLEE revealed greater genetic diversity among strains of Y. enterocolitica biovar 1A and clustered strains in four groups, while MLRT grouped the strains into two groups. BURST analysis of MLRT data nevertheless provided newer insights into the probable evolution of clinical strains from aquatic strains.

Genetic patterns in European geometrid moths revealed by the Barcode Index Number (BIN system.

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Axel Hausmann

Full Text Available BACKGROUND: The geometrid moths of Europe are one of the best investigated insect groups in traditional taxonomy making them an ideal model group to test the accuracy of the Barcode Index Number (BIN system of BOLD (Barcode of Life Datasystems, a method that supports automated, rapid species delineation and identification. METHODOLOGY/PRINCIPAL FINDINGS: This study provides a DNA barcode library for 219 of the 249 European geometrid moth species (88% in five selected subfamilies. The data set includes COI sequences for 2130 specimens. Most species (93% were found to possess diagnostic barcode sequences at the European level while only three species pairs (3% were genetically indistinguishable in areas of sympatry. As a consequence, 97% of the European species we examined were unequivocally discriminated by barcodes within their natural areas of distribution. We found a 1:1 correspondence between BINs and traditionally recognized species for 67% of these species. Another 17% of the species (15 pairs, three triads shared BINs, while specimens from the remaining species (18% were divided among two or more BINs. Five of these species are mixtures, both sharing and splitting BINs. For 82% of the species with two or more BINs, the genetic splits involved allopatric populations, many of which have previously been hypothesized to represent distinct species or subspecies. CONCLUSIONS/SIGNIFICANCE: This study confirms the effectiveness of DNA barcoding as a tool for species identification and illustrates the potential of the BIN system to characterize formal genetic units independently of an existing classification. This suggests the system can be used to efficiently assess the biodiversity of large, poorly known assemblages of organisms. For the moths examined in this study, cases of discordance between traditionally recognized species and BINs arose from several causes including overlooked species, synonymy, and cases where DNA barcodes revealed

Genetic diversity revealed by AFLP markers in Albanian goat breeds

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Hoda Anila

2012-01-01

Full Text Available The amplified fragment length polymorphism (AFLP technique with three EcoRI/TaqI primer combinations was used in 185 unrelated individuals, representative of 6 local goat breeds of Albania, and 107 markers were generated. The mean Nei’s expected heterozygosity value for the whole population was 0.199 and the mean Shannon index was 0.249, indicating a high level of within-breed diversity. Wright’s FST index, Nei’s unbiased genetic distance and Reynolds’ genetic distance were calculated. Pairwise Fst values among the populations ranged from 0.019 to 0.047. A highly significant average FST of 0.031 was estimated, showing a low level of breed subdivision. Most of the variation is accounted for by differences among individuals. Cluster analysis based on Reynolds’ genetic distance between breeds and PCA were performed. An individual UPGMA tree based on Jaccard’s similarity index showed clusters with individuals from all goat breeds. Analysis of population structure points to a high level of admixture among breeds.

A forward genetic screen reveals essential and non-essential RNAi factors in Paramecium tetraurelia

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Marker, Simone; Carradec, Quentin; Tanty, Véronique; Arnaiz, Olivier; Meyer, Eric

2014-01-01

In most eukaryotes, small RNA-mediated gene silencing pathways form complex interacting networks. In the ciliate Paramecium tetraurelia, at least two RNA interference (RNAi) mechanisms coexist, involving distinct but overlapping sets of protein factors and producing different types of short interfering RNAs (siRNAs). One is specifically triggered by high-copy transgenes, and the other by feeding cells with double-stranded RNA (dsRNA)-producing bacteria. In this study, we designed a forward genetic screen for mutants deficient in dsRNA-induced silencing, and a powerful method to identify the relevant mutations by whole-genome sequencing. We present a set of 47 mutant alleles for five genes, revealing two previously unknown RNAi factors: a novel Paramecium-specific protein (Pds1) and a Cid1-like nucleotidyl transferase. Analyses of allelic diversity distinguish non-essential and essential genes and suggest that the screen is saturated for non-essential, single-copy genes. We show that non-essential genes are specifically involved in dsRNA-induced RNAi while essential ones are also involved in transgene-induced RNAi. One of the latter, the RNA-dependent RNA polymerase RDR2, is further shown to be required for all known types of siRNAs, as well as for sexual reproduction. These results open the way for the dissection of the genetic complexity, interconnection, mechanisms and natural functions of RNAi pathways in P. tetraurelia. PMID:24860163

Whole-Genome Analysis of Three Yeast Strains Used for Production of Sherry-Like Wines Revealed Genetic Traits Specific to Flor Yeasts

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Eldarov, Mikhail A.; Beletsky, Alexey V.; Tanashchuk, Tatiana N.; Kishkovskaya, Svetlana A.; Ravin, Nikolai V.; Mardanov, Andrey V.

2018-01-01

Flor yeast strains represent a specialized group of Saccharomyces cerevisiae yeasts used for biological wine aging. We have sequenced the genomes of three flor strains originated from different geographic regions and used for production of sherry-like wines in Russia. According to the obtained phylogeny of 118 yeast strains, flor strains form very tight cluster adjacent to the main wine clade. SNP analysis versus available genomes of wine and flor strains revealed 2,270 genetic variants in 1,337 loci specific to flor strains. Gene ontology analysis in combination with gene content evaluation revealed a complex landscape of possibly adaptive genetic changes in flor yeast, related to genes associated with cell morphology, mitotic cell cycle, ion homeostasis, DNA repair, carbohydrate metabolism, lipid metabolism, and cell wall biogenesis. Pangenomic analysis discovered the presence of several well-known “non-reference” loci of potential industrial importance. Events of gene loss included deletions of asparaginase genes, maltose utilization locus, and FRE-FIT locus involved in iron transport. The latter in combination with a flor-yeast-specific mutation in the Aft1 transcription factor gene is likely to be responsible for the discovered phenotype of increased iron sensitivity and improved iron uptake of analyzed strains. Expansion of the coding region of the FLO11 flocullin gene and alteration of the balance between members of the FLO gene family are likely to positively affect the well-known propensity of flor strains for velum formation. Our study provides new insights in the nature of genetic variation in flor yeast strains and demonstrates that different adaptive properties of flor yeast strains could have evolved through different mechanisms of genetic variation. PMID:29867869

Mitochondrial DNA analyses revealed low genetic diversity in the endangered Indian wild ass Equus hemionus khur.

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Khaire, Devendra; Atkulwar, Ashwin; Farah, Sameera; Baig, Mumtaz

2017-09-01

The Indian wild ass Equus hemionus khur, belonging to ass-like equid branch, inhabits the dry and arid desert of the Little Rann of Kutch, Gujarat. The E. h. khur is the sole survivor of Asiatic wild ass species/subspecies in South Asia. To provide first ever insights into the genetic diversity, phylogeny, and demography of the endangered Indian wild ass, we sampled 52 free-ranging individuals from the Little Rann of Kutch by using a non-invasive methodology. The sequencing of 230 bp in cytochrome b (Cyt b) and displacement loop (D-loop) region revealed that current ∼4000 extant population of Indian wild ass harbours low genetic diversity. Phylogenetic analyses confirmed that E. h. khur, E. h. onager, and E. h. kulan belong to a single strict monophyletic clade. Therefore, we suggest the delimitation of the five E. hemionus subspecies in vogue to a single species E. hemionus. The application of molecular clock confirmed that the Asiatic wild ass had undergone diversification 0.65 Million years ago. Demographic measurements assessed using a Bayesian skyline plot demonstrated decline in the maternal effective population size of the Indian wild ass during different periods; these periods coincided with the origin and rise of the Indus civilization in the northwest of the Indian subcontinent during the Neolithic. In conclusion, maintaining high genetic diversity in the existing isolated population of 4000 Indian wild asses inhabiting the wild ass sanctuary is important compared with subspecies preservation alone.

A genetic analysis of segregation distortion revealed by molecular ...

Indian Academy of Sciences (India)

Journal of Genetics, Vol. 90, No. ... Segregation analysis was based on 64 molecular markers, including 26 .... FHB of RIL populations was controlled by quantitative trait ... The authors acknowledge financial support by the National Basic.

Phylogenetic Studies of the Three RNA Silencing Suppressor Genes of South American CTV Isolates Reveal the Circulation of a Novel Genetic Lineage

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María José Benítez-Galeano

2015-07-01

Full Text Available Citrus Tristeza Virus (CTV is the most economically important virus of citrus worldwide. Genetic diversity and population structure of CTV isolates from all citrus growing areas from Uruguay were analyzed by RT-PCR and cloning of the three RNA silencing suppressor genes (p25, p20 and p23. Bayesian phylogenetic analysis revealed the circulation of three known genotypes (VT, T3, T36 in the country, and the presence of a new genetic lineage composed by isolates from around the world, mainly from South America. Nucleotide and amino acid identity values for this new genetic lineage were both higher than 97% for the three analyzed regions. Due to incongruent phylogenetic relationships, recombination analysis was performed using Genetic Algorithms for Recombination Detection (GARD and SimPlot software. Recombination events between previously described CTV isolates were detected. High intra-sample variation was found, confirming the co-existence of different genotypes into the same plant. This is the first report describing: (1 the genetic diversity of Uruguayan CTV isolates circulating in the country and (2 the circulation of a novel CTV genetic lineage, highly present in the South American region. This information may provide assistance to develop an effective cross-protection program.

Genetic origin of goat populations in Oman revealed by mitochondrial DNA analysis

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Gaafar, Osman Mahgoub; Costa, Vânia; Neira, Agusto Luzuriaga; Al-Atiyat, Raed Mahmoud; Beja-Pereira, Albano

2017-01-01

The Sultanate of Oman has a complex mosaic of livestock species and production systems, but the genetic diversity, demographic history or origins of these Omani animals has not been expensively studied. Goats might constitute one of the most abundant and important domestic livestock species since the Neolithic transition. Here, we examined the genetic diversity, origin, population structure and demographic history of Omani goats. Specifically, we analyzed a 525-bp fragment of the first hypervariable region of the mitochondrial DNA (mtDNA) control region from 69 Omani individuals and compared this fragment with 17 mtDNA sequences from Somalia and Yemen as well as 18 wild goat species and 1,198 previously published goat sequences from neighboring countries. The studied goat breeds show substantial diversity. The haplotype and nucleotide diversities of Omani goats were found equal to 0.983 ± 0.006 and 0.0284 ± 0.014, respectively. The phylogenetic analyses allowed us to classify Omani goats into three mtDNA haplogroups (A, B and G): haplogroup A was found to be predominant and widely distributed and accounted for 80% of all samples, and haplogroups B and G exhibited low frequencies. Phylogenetic comparisons with wild goats revealed that five of the native Omani goat populations originate from Capra aegagrus. Furthermore, most comparisons of pairwise population FST values within and between these five Omani goat breeds as well as between Omani goats and nine populations from nearby countries were not significant. These results suggest strong gene flow among goat populations caused by the extensive transport of goats and the frequent movements of human populations in ancient Arabia. The findings improve our understanding of the migration routes of modern goats from their region of domestication into southeastern Arabia and thereby shed light on human migratory and commercial networks during historical times. PMID:29281717

Genetic origin of goat populations in Oman revealed by mitochondrial DNA analysis.

Science.gov (United States)

Al-Araimi, Nasser Ali; Gaafar, Osman Mahgoub; Costa, Vânia; Neira, Agusto Luzuriaga; Al-Atiyat, Raed Mahmoud; Beja-Pereira, Albano

2017-01-01

The Sultanate of Oman has a complex mosaic of livestock species and production systems, but the genetic diversity, demographic history or origins of these Omani animals has not been expensively studied. Goats might constitute one of the most abundant and important domestic livestock species since the Neolithic transition. Here, we examined the genetic diversity, origin, population structure and demographic history of Omani goats. Specifically, we analyzed a 525-bp fragment of the first hypervariable region of the mitochondrial DNA (mtDNA) control region from 69 Omani individuals and compared this fragment with 17 mtDNA sequences from Somalia and Yemen as well as 18 wild goat species and 1,198 previously published goat sequences from neighboring countries. The studied goat breeds show substantial diversity. The haplotype and nucleotide diversities of Omani goats were found equal to 0.983 ± 0.006 and 0.0284 ± 0.014, respectively. The phylogenetic analyses allowed us to classify Omani goats into three mtDNA haplogroups (A, B and G): haplogroup A was found to be predominant and widely distributed and accounted for 80% of all samples, and haplogroups B and G exhibited low frequencies. Phylogenetic comparisons with wild goats revealed that five of the native Omani goat populations originate from Capra aegagrus. Furthermore, most comparisons of pairwise population FST values within and between these five Omani goat breeds as well as between Omani goats and nine populations from nearby countries were not significant. These results suggest strong gene flow among goat populations caused by the extensive transport of goats and the frequent movements of human populations in ancient Arabia. The findings improve our understanding of the migration routes of modern goats from their region of domestication into southeastern Arabia and thereby shed light on human migratory and commercial networks during historical times.

AFLP marker analysis revealing genetic structure of the tree Parapiptadenia rigida (Benth. Brenan (Leguminosae-Mimosoideae in the southern Brazilian Tropical Rainforest

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Laís Bérgamo de Souza

2013-01-01

Full Text Available Parapiptadenia rigida is a tropical early secondary succession tree characteristic of the Tropical Atlantic Rainforest. This species is of great ecological importance in the recovery of degraded areas. In this study we investigated the variability and population genetic structure of eight populations of P. rigida. Five AFLP primer combinations were used in a sample of 159 individuals representing these eight populations, rendering a total of 126 polymorphic fragments. The averages of percentage of polymorphic loci, gene diversity, and Shannon index were 60.45%, 0.217, and 0.322, respectively. A significant correlation between the population genetic variability and the population sizes was observed. The genetic variability within populations (72.20% was higher than between these (22.80%. No perfect correlation was observed between geographic and genetic distances, which might be explained by differences in deforestation intensities that occurred in these areas. A dendrogram constructed by the UPGMA method revealed the formation of two clusters, these also confirmed by Bayesian analysis for the number of K cluster. These results show that it is necessary to develop urgent management strategies for the conservation of certain populations of P. rigida, while other populations still preserve reasonably high levels of genetic variability.

A genetic screen for vascular mutants in zebrafish reveals dynamic roles for Vegf/Plcg1 signaling during artery development.

Science.gov (United States)

Covassin, L D; Siekmann, A F; Kacergis, M C; Laver, E; Moore, J C; Villefranc, J A; Weinstein, B M; Lawson, N D

2009-05-15

In this work we describe a forward genetic approach to identify mutations that affect blood vessel development in the zebrafish. By applying a haploid screening strategy in a transgenic background that allows direct visualization of blood vessels, it was possible to identify several classes of mutant vascular phenotypes. Subsequent characterization of mutant lines revealed that defects in Vascular endothelial growth factor (Vegf) signaling specifically affected artery development. Comparison of phenotypes associated with different mutations within a functional zebrafish Vegf receptor-2 ortholog (referred to as kdr-like, kdrl) revealed surprisingly varied effects on vascular development. In parallel, we identified an allelic series of mutations in phospholipase c gamma 1 (plcg1). Together with in vivo structure-function analysis, our results suggest a requirement for Plcg1 catalytic activity downstream of receptor tyrosine kinases. We further find that embryos lacking both maternal and zygotic plcg1 display more severe defects in artery differentiation but are otherwise similar to zygotic mutants. Finally, we demonstrate through mosaic analysis that plcg1 functions autonomously in endothelial cells. Together our genetic analyses suggest that Vegf/Plcg1 signaling acts at multiple time points and in different signaling contexts to mediate distinct aspects of artery development.

Identification of Lygus hesperus by DNA barcoding reveals insignificant levels of genetic structure among distant and habitat diverse populations.

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Changqing Zhou

Full Text Available BACKGROUND: The western tarnished plant bug Lygus hesperus is an economically important pest that belongs to a complex of morphologically similar species that makes identification problematic. The present study provides evidence for the use of DNA barcodes from populations of L. hesperus from the western United States of America for accurate identification. METHODOLOGY/PRINCIPAL FINDINGS: This study reports DNA barcodes for 134 individuals of the western tarnished plant bug from alfalfa and strawberry agricultural fields in the western United States of America. Sequence divergence estimates of <3% reveal that morphologically variable individuals presumed to be L. hesperus were accurately identified. Paired estimates of F(st and subsequent estimates of gene flow show that geographically distinct populations of L. hesperus are genetically similar. Therefore, our results support and reinforce the relatively recent (<100 years migration of the western tarnished plant bug into agricultural habitats across the western United States. CONCLUSIONS/SIGNIFICANCE: This study reveals that despite wide host plant usage and phenotypically plastic morphological traits, the commonly recognized western tarnished plant bug belongs to a single species, Lygus hesperus. In addition, no significant genetic structure was found for the geographically diverse populations of western tarnished plant bug used in this study.

"It's challenging on a personal level"--exploring the 'lived experience' of Australian and Canadian prenatal genetic counselors.

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Menezes, Melody A; Hodgson, Jan M; Sahhar, Margaret A; Aitken, Maryanne; Metcalfe, Sylvia A

2010-12-01

Prenatal genetic counselors work with clients who are at risk of having a child with a fetal anomaly, or who have been diagnosed with a fetal anomaly. This can raise challenging ethical, moral and legal issues for both clients and counselors. Few studies have explored whether this type of work impacts on genetic counselors themselves. Interviews were conducted with 15 prenatal genetic counselors, five from Toronto, Canada and ten from Melbourne, Australia. A qualitative approach was used to allow for an in-depth exploration of the experiences of genetic counselors working in the prenatal setting. While participants reported that working in a prenatal setting affected them in several ways, this paper focuses on one particular unanticipated finding--that of the impact experienced by counselors from both countries while working when pregnant.

Conservation of eelgrass (Zostera marina) genetic diversity in a mesocosm-based restoration experiment.

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Ort, Brian S; Cohen, C Sarah; Boyer, Katharyn E; Reynolds, Laura K; Tam, Sheh May; Wyllie-Echeverria, Sandy

2014-01-01

Eelgrass (Zostera marina) forms the foundation of an important shallow coastal community in protected estuaries and bays. Widespread population declines have stimulated restoration efforts, but these have often overlooked the importance of maintaining the evolutionary potential of restored populations by minimizing the reduction in genetic diversity that typically accompanies restoration. In an experiment simulating a small-scale restoration, we tested the effectiveness of a buoy-deployed seeding technique to maintain genetic diversity comparable to the seed source populations. Seeds from three extant source populations in San Francisco Bay were introduced into eighteen flow-through baywater mesocosms. Following seedling establishment, we used seven polymorphic microsatellite loci to compare genetic diversity indices from 128 shoots to those found in the source populations. Importantly, allelic richness and expected heterozygosity were not significantly reduced in the mesocosms, which also preserved the strong population differentiation present among source populations. However, the inbreeding coefficient F IS was elevated in two of the three sets of mesocosms when they were grouped according to their source population. This is probably a Wahlund effect from confining all half-siblings within each spathe to a single mesocosm, elevating F IS when the mesocosms were considered together. The conservation of most alleles and preservation of expected heterozygosity suggests that this seeding technique is an improvement over whole-shoot transplantation in the conservation of genetic diversity in eelgrass restoration efforts.

Conservation of eelgrass (Zostera marina genetic diversity in a mesocosm-based restoration experiment.

Directory of Open Access Journals (Sweden)

Brian S Ort

Full Text Available Eelgrass (Zostera marina forms the foundation of an important shallow coastal community in protected estuaries and bays. Widespread population declines have stimulated restoration efforts, but these have often overlooked the importance of maintaining the evolutionary potential of restored populations by minimizing the reduction in genetic diversity that typically accompanies restoration. In an experiment simulating a small-scale restoration, we tested the effectiveness of a buoy-deployed seeding technique to maintain genetic diversity comparable to the seed source populations. Seeds from three extant source populations in San Francisco Bay were introduced into eighteen flow-through baywater mesocosms. Following seedling establishment, we used seven polymorphic microsatellite loci to compare genetic diversity indices from 128 shoots to those found in the source populations. Importantly, allelic richness and expected heterozygosity were not significantly reduced in the mesocosms, which also preserved the strong population differentiation present among source populations. However, the inbreeding coefficient F IS was elevated in two of the three sets of mesocosms when they were grouped according to their source population. This is probably a Wahlund effect from confining all half-siblings within each spathe to a single mesocosm, elevating F IS when the mesocosms were considered together. The conservation of most alleles and preservation of expected heterozygosity suggests that this seeding technique is an improvement over whole-shoot transplantation in the conservation of genetic diversity in eelgrass restoration efforts.

Mitochondrial and nuclear markers reveal a lack of genetic structure in the entocommensal nemertean Malacobdella arrokeana in the Patagonian gulfs

Science.gov (United States)

Alfaya, José E. F.; Bigatti, Gregorio; Machordom, Annie

2013-06-01

Malacobdella arrokeana is an entocommensal nemertean exclusively found in the bivalve geoduck Panopea abbreviata, and it is the only representative of the genus in the southern hemisphere. To characterize its genetic diversity, population structure and recent demographic history, we conducted the first genetic survey on this species, using sequence data for the cytochrome oxidase I gene (COI), 16S rRNA (16S) and the internal transcribed spacer (ITS2). Only four different ITS2 genotypes were found in the whole sample, and the two main haplotypes identified in the mitochondrial dataset were present among all localities with a diversity ranging from 0.583 to 0.939. Nucleotide diversity was low (π = 0.001-0.002). No significant genetic structure was detected between populations, and mismatch distribution patterns and neutrality tests results are consistent with a population in expansion or under selection. Analysis of molecular variance (AMOVA) revealed that the largest level of variance observed was due to intrapopulation variation (100, 100 and 94.39 % for 16S, COI and ITS2, respectively). F st values were also non-significant. The observed lack of population structure is likely due to high levels of genetic connectivity in combination with the lack or permeability of biogeographic barriers and episodes of habitat modification.

Detection of Genetically Modified Food: Has Your Food Been Genetically Modified?

Science.gov (United States)

Brandner, Diana L.

2002-01-01

Explains the benefits and risks of genetically-modified foods and describes methods for genetically modifying food. Presents a laboratory experiment using a polymerase chain reaction (PCR) test to detect foreign DNA in genetically-modified food. (Contains 18 references.) (YDS)

Whole-exome sequencing reveals genetic variants associated with chronic kidney disease characterized by tubulointerstitial damages in North Central Region, Sri Lanka.

Science.gov (United States)

Nanayakkara, Shanika; Senevirathna, S T M L D; Parahitiyawa, Nipuna B; Abeysekera, Tilak; Chandrajith, Rohana; Ratnatunga, Neelakanthi; Hitomi, Toshiaki; Kobayashi, Hatasu; Harada, Kouji H; Koizumi, Akio

2015-09-01

The familial clustering observed in chronic kidney disease of uncertain etiology (CKDu) characterized by tubulointerstitial damages in the North Central Region of Sri Lanka strongly suggests the involvement of genetic factors in its pathogenesis. The objective of the present study is to use whole-exome sequencing to identify the genetic variants associated with CKDu. Whole-exome sequencing of eight CKDu cases and eight controls was performed, followed by direct sequencing of candidate loci in 301 CKDu cases and 276 controls. Association study revealed rs34970857 (c.658G > A/p.V220M) located in the KCNA10 gene encoding a voltage-gated K channel as the most promising SNP with the highest odds ratio of 1.74. Four rare variants were identified in gene encoding Laminin beta2 (LAMB2) which is known to cause congenital nephrotic syndrome. Three out of four variants in LAMB2 were novel variants found exclusively in cases. Genetic investigations provide strong evidence on the presence of genetic susceptibility for CKDu. Possibility of presence of several rare variants associated with CKDu in this population is also suggested.

Genetic Structure and Demographic History Reveal Migration of the Diamondback Moth Plutella xylostella (Lepidoptera: Plutellidae) from the Southern to Northern Regions of China

Science.gov (United States)

Wei, Shu-Jun; Shi, Bao-Cai; Gong, Ya-Jun; Jin, Gui-Hua; Chen, Xue-Xin; Meng, Xiang-Feng

2013-01-01

The diamondback moth Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae) is one of the most destructive insect pests of cruciferous plants worldwide. Biological, ecological and genetic studies have indicated that this moth is migratory in many regions around the world. Although outbreaks of this pest occur annually in China and cause heavy damage, little is known concerning its migration. To better understand its migration pattern, we investigated the population genetic structure and demographic history of the diamondback moth by analyzing 27 geographical populations across China using four mitochondrial genes and nine microsatellite loci. The results showed that high haplotype diversity and low nucleotide diversity occurred in the diamondback moth populations, a finding that is typical for migratory species. No genetic differentiation among all populations and no correlation between genetic and geographical distance were found. However, pairwise analysis of the mitochondrial genes has indicated that populations from the southern region were more differentiated than those from the northern region. Gene flow analysis revealed that the effective number of migrants per generation into populations of the northern region is very high, whereas that into populations of the southern region is quite low. Neutrality testing, mismatch distribution and Bayesian Skyline Plot analyses based on mitochondrial genes all revealed that deviation from Hardy-Weinberg equilibrium and sudden expansion of the effective population size were present in populations from the northern region but not in those from the southern region. In conclusion, all our analyses strongly demonstrated that the diamondback moth migrates within China from the southern to northern regions with rare effective migration in the reverse direction. Our research provides a successful example of using population genetic approaches to resolve the seasonal migration of insects. PMID:23565158

Is the experience of thermal pain genetics dependent?

DEFF Research Database (Denmark)

Horjales-Araujo, Emilia; Dahl, Joergen B

2015-01-01

It is suggested that genetic variations explain a significant portion of the variability in pain perception; therefore, increased understanding of pain-related genetic influences may identify new targets for therapies and treatments. The relative contribution of the different genes to the varianc...

Genetic and environmental variance in content dimensions of the MMPI.

Science.gov (United States)

Rose, R J

1988-08-01

To evaluate genetic and environmental variance in the Minnesota Multiphasic Personality Inventory (MMPI), I studied nine factor scales identified in the first item factor analysis of normal adult MMPIs in a sample of 820 adolescent and young adult co-twins. Conventional twin comparisons documented heritable variance in six of the nine MMPI factors (Neuroticism, Psychoticism, Extraversion, Somatic Complaints, Inadequacy, and Cynicism), whereas significant influence from shared environmental experience was found for four factors (Masculinity versus Femininity, Extraversion, Religious Orthodoxy, and Intellectual Interests). Genetic variance in the nine factors was more evident in results from twin sisters than those of twin brothers, and a developmental-genetic analysis, using hierarchical multiple regressions of double-entry matrixes of the twins' raw data, revealed that in four MMPI factor scales, genetic effects were significantly modulated by age or gender or their interaction during the developmental period from early adolescence to early adulthood.

Experiencing the genetic body: parents' encounters with pediatric clinical genetics.

Science.gov (United States)

Raspberry, Kelly; Skinner, Debra

2007-01-01

Because of advancements in genetic research and technologies, the clinical practice of genetics is becoming a prevalent component of biomedicine. As the genetic basis for more and more diseases are found, it is possible that ways of experiencing health, illness, identity, kin relations, and the body are becoming geneticized, or understood within a genetic model of disease. Yet, other models and relations that go beyond genetic explanations also shape interpretations of health and disease. This article explores how one group of individuals for whom genetic disorder is highly relevant formulates their views of the body in light of genetic knowledge. Using data from an ethnographic study of 106 parents or potential parents of children with known or suspected genetic disorders who were referred to a pediatric genetic counseling and evaluation clinic in the southeastern United States, we find that these parents do, to some degree, perceive of their children's disorders in terms of a genetic body that encompasses two principal qualities: a sense of predetermined health and illness and an awareness of a profound historicity that reaches into the past and extends into the present and future. They experience this genetic body as both fixed and historical, but they also express ideas of a genetic body made less deterministic by their own efforts and future possibilities. This account of parents' experiences with genetics and clinical practice contributes to a growing body of work on the ways in which genetic information and technologies are transforming popular and medical notions of the body, and with it, health, illness, kinship relations, and personal and social identities.

Application of case teaching in genetics courses to students majoring in forestry.

Science.gov (United States)

Wang, Qin-Mei; Cui, Jian-Guo; Yu, Chang-Zhi; Zhang, Zhi; Wu, Yue-Liang; Zhang, Li-Jie; Lin, Mei

2017-10-20

Undergraduate students majoring in forestry generally reflect that genetics is one of the most difficult compul-sory courses, because the traditional teaching method is difficult to satisfy their needs. According to the theoretical charac-teristics of forestry and actual demands of the students, in the light of teaching and research experience in recent years, we adopted a series of typical genetic cases such as 'opening coffin to identify relatives', stem-throne of Lycium ruthenicum Murr, and magic powers in Harry Potter. Our practices revealed that the case teaching in genetics could train good personality traits, learning abilities and creativity of the students, stimulate their interests and initiatives in learning, and increase systematic learning.

Effects of Freshwater Pollution on the Genetics of Zebra Mussels (Dreissena polymorpha at the Molecular and Population Level

Directory of Open Access Journals (Sweden)

Emilia G. Thomas

2014-01-01

Full Text Available Revealing long-term effects of contaminants on the genetic structure of organisms inhabiting polluted environments should encompass analyses at the population, molecular, and cellular level. Following this concept, we studied the genetic constitution of zebra mussel populations from a polluted (Dp and reference sites (Cl at the river Drava, Croatia, and applied microsatellite and DNA damage analyses (Comet assay, micronucleus test (MNT. Additionally, mussels from both populations were exposed to polluted wastewater in the laboratory for three days, and DNA damage was analyzed to evaluate acclimatization and genetic adaptation of the investigated populations to the polluted environment. The two populations differed in their genetic constitution. Microsatellite analysis suggested that Dp had undergone a genetic bottleneck. Comet assay did not indicate any difference in DNA damage between the two populations, but MNT revealed that Dp had an increased percentage of micronuclei in hemocytes in comparison to Cl. The laboratory experiment revealed that Dp had a lower percentage of tail DNA and a higher percentage of micronuclei than Cl. These differences between populations were possibly caused by an overall decreased fitness of Dp due to genetic drift and by an enhanced DNA repair mechanism due to acclimatization to pollution in the source habitat.

Effects of freshwater pollution on the genetics of zebra mussels (Dreissena polymorpha) at the molecular and population level.

Science.gov (United States)

Thomas, Emilia G; Srut, Maja; Stambuk, Anamaria; Klobučar, Göran I V; Seitz, Alfred; Griebeler, Eva Maria

2014-01-01

Revealing long-term effects of contaminants on the genetic structure of organisms inhabiting polluted environments should encompass analyses at the population, molecular, and cellular level. Following this concept, we studied the genetic constitution of zebra mussel populations from a polluted (Dp) and reference sites (Cl) at the river Drava, Croatia, and applied microsatellite and DNA damage analyses (Comet assay, micronucleus test (MNT)). Additionally, mussels from both populations were exposed to polluted wastewater in the laboratory for three days, and DNA damage was analyzed to evaluate acclimatization and genetic adaptation of the investigated populations to the polluted environment. The two populations differed in their genetic constitution. Microsatellite analysis suggested that Dp had undergone a genetic bottleneck. Comet assay did not indicate any difference in DNA damage between the two populations, but MNT revealed that Dp had an increased percentage of micronuclei in hemocytes in comparison to Cl. The laboratory experiment revealed that Dp had a lower percentage of tail DNA and a higher percentage of micronuclei than Cl. These differences between populations were possibly caused by an overall decreased fitness of Dp due to genetic drift and by an enhanced DNA repair mechanism due to acclimatization to pollution in the source habitat.

Primary care providers' lived experiences of genetics in practice.

Science.gov (United States)

Harding, Brittany; Webber, Colleen; Ruhland, Lucia; Dalgarno, Nancy; Armour, Christine M; Birtwhistle, Richard; Brown, Glenn; Carroll, June C; Flavin, Michael; Phillips, Susan; MacKenzie, Jennifer J

2018-04-26

To effectively translate genetic advances into practice, engagement of primary care providers (PCPs) is essential. Using a qualitative, phenomenological methodology, we analyzed key informant interviews and focus groups designed to explore perspectives of urban and rural PCPs. PCPs endorsed a responsibility to integrate genetics into their practices and expected advances in genetic medicine to expand. However, PCPs reported limited knowledge and difficulties accessing resources, experts, and continuing education. Rural practitioners' additional concerns included cost, distance, and poor patient engagement. PCPs' perspectives are crucial to develop relevant educational and systems-based interventions to further expand genetic medicine in primary care.

Standing genetic variation as a major contributor to adaptation in the Virginia chicken lines selection experiment.

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Sheng, Zheya; Pettersson, Mats E; Honaker, Christa F; Siegel, Paul B; Carlborg, Örjan

2015-10-01

Artificial selection provides a powerful approach to study the genetics of adaptation. Using selective-sweep mapping, it is possible to identify genomic regions where allele-frequencies have diverged during selection. To avoid false positive signatures of selection, it is necessary to show that a sweep affects a selected trait before it can be considered adaptive. Here, we confirm candidate, genome-wide distributed selective sweeps originating from the standing genetic variation in a long-term selection experiment on high and low body weight of chickens. Using an intercross between the two divergent chicken lines, 16 adaptive selective sweeps were confirmed based on their association with the body weight at 56 days of age. Although individual additive effects were small, the fixation for alternative alleles across the loci contributed at least 40 % of the phenotypic difference for the selected trait between these lines. The sweeps contributed about half of the additive genetic variance present within and between the lines after 40 generations of selection, corresponding to a considerable portion of the additive genetic variance of the base population. Long-term, single-trait, bi-directional selection in the Virginia chicken lines has resulted in a gradual response to selection for extreme phenotypes without a drastic reduction in the genetic variation. We find that fixation of several standing genetic variants across a highly polygenic genetic architecture made a considerable contribution to long-term selection response. This provides new fundamental insights into the dynamics of standing genetic variation during long-term selection and adaptation.

Sardinian Population (Italy): a Genetic Review

African Journals Online (AJOL)

thou

, according to the classification suggested by Contini (1979). The genetic ... and to have maintained a genetic identity through their evolution: the cluster constituted ...... HLA class II haplotypes reveals that the Sardinian population is genetically.

Development, cross-species/genera transferability of novel EST-SSR markers and their utility in revealing population structure and genetic diversity in sugarcane

KAUST Repository

Singh, Ram K.

2013-07-01

Sugarcane (Saccharum spp. hybrid) with complex polyploid genome requires a large number of informative DNA markers for various applications in genetics and breeding. Despite the great advances in genomic technology, it is observed in several crop species, especially in sugarcane, the availability of molecular tools such as microsatellite markers are limited. Now-a-days EST-SSR markers are preferred to genomic SSR (gSSR) as they represent only the functional part of the genome, which can be easily associated with desired trait. The present study was taken up with a new set of 351 EST-SSRs developed from the 4085 non redundant EST sequences of two Indian sugarcane cultivars. Among these EST-SSRs, TNR containing motifs were predominant with a frequency of 51.6%. Thirty percent EST-SSRs showed homology with annotated protein. A high frequency of SSRs was found in the 5\\'UTR and in the ORF (about 27%) and a low frequency was observed in the 3\\'UTR (about 8%). Two hundred twenty-seven EST-SSRs were evaluated, in sugarcane, allied genera of sugarcane and cereals, and 134 of these have revealed polymorphism with a range of PIC value 0.12 to 0.99. The cross transferability rate ranged from 87.0% to 93.4% in Saccharum complex, 80.0% to 87.0% in allied genera, and 76.0% to 80.0% in cereals. Cloning and sequencing of EST-SSR size variant amplicons revealed that the variation in the number of repeat-units was the main source of EST-SSR fragment polymorphism. When 124 sugarcane accessions were analyzed for population structure using model-based approach, seven genetically distinct groups or admixtures thereof were observed in sugarcane. Results of principal coordinate analysis or UPGMA to evaluate genetic relationships delineated also the 124 accessions into seven groups. Thus, a high level of polymorphism adequate genetic diversity and population structure assayed with the EST-SSR markers not only suggested their utility in various applications in genetics and genomics in

Genetic analysis of Aedes albopictus (Diptera, Culicidae) reveals a deep divergence in the original regions.

Science.gov (United States)

Ruiling, Zhang; Tongkai, Liu; Zhendong, Huang; Guifen, Zhuang; Dezhen, Ma; Zhong, Zhang

2018-05-02

Aedes albopictus has been described as one of the 100 worst invasive species in the world. This mosquito originated from southeastern Asia and currently has a widespread presence in every continent except Antarctica. The rapid global expansion of Ae. albopictus has increased public health concerns about arbovirus-related disease threats. Adaptation, adaption to novel areas is a biological challenge for invasive species, and the underlying processes can be studied at the molecular level. In this study, genetic analysis was performed using mitochondrial gene NADH dehydrogenase subunit 5 (ND5), based on both native and invasive populations. Altogether, 38 haplotypes were detected with H1 being the dominant and widely distributed in 21 countries. Both phylogenetic and network analyses supported the existence of five clades, with only clade I being involved in the subsequent global spread of Asian tiger mosquito. The other four clades (II, III, IV and V) were restricted to their original regions, which could be ancestral populations that had diverged from clade I in the early stages of evolution. Neutrality tests suggested that most of the populations had experienced recent expansion. Analysis of molecular variance and the population-pair statistic F ST revealed that most populations lacked genetic structure, while high variability was detected within populations. Multiple and independent human-mediated introductions may explain the present results. Copyright © 2018 Elsevier B.V. All rights reserved.

Multilocus Sequence Analysis of Nectar Pseudomonads Reveals High Genetic Diversity and Contrasting Recombination Patterns

Science.gov (United States)

Álvarez-Pérez, Sergio; de Vega, Clara; Herrera, Carlos M.

2013-01-01

The genetic and evolutionary relationships among floral nectar-dwelling Pseudomonas ‘sensu stricto’ isolates associated to South African and Mediterranean plants were investigated by multilocus sequence analysis (MLSA) of four core housekeeping genes (rrs, gyrB, rpoB and rpoD). A total of 35 different sequence types were found for the 38 nectar bacterial isolates characterised. Phylogenetic analyses resulted in the identification of three main clades [nectar groups (NGs) 1, 2 and 3] of nectar pseudomonads, which were closely related to five intrageneric groups: Pseudomonas oryzihabitans (NG 1); P. fluorescens, P. lutea and P. syringae (NG 2); and P. rhizosphaerae (NG 3). Linkage disequilibrium analysis pointed to a mostly clonal population structure, even when the analysis was restricted to isolates from the same floristic region or belonging to the same NG. Nevertheless, signatures of recombination were observed for NG 3, which exclusively included isolates retrieved from the floral nectar of insect-pollinated Mediterranean plants. In contrast, the other two NGs comprised both South African and Mediterranean isolates. Analyses relating diversification to floristic region and pollinator type revealed that there has been more unique evolution of the nectar pseudomonads within the Mediterranean region than would be expected by chance. This is the first work analysing the sequence of multiple loci to reveal geno- and ecotypes of nectar bacteria. PMID:24116076

Multilocus sequence analysis of nectar pseudomonads reveals high genetic diversity and contrasting recombination patterns.

Science.gov (United States)

Alvarez-Pérez, Sergio; de Vega, Clara; Herrera, Carlos M

2013-01-01

The genetic and evolutionary relationships among floral nectar-dwelling Pseudomonas 'sensu stricto' isolates associated to South African and Mediterranean plants were investigated by multilocus sequence analysis (MLSA) of four core housekeeping genes (rrs, gyrB, rpoB and rpoD). A total of 35 different sequence types were found for the 38 nectar bacterial isolates characterised. Phylogenetic analyses resulted in the identification of three main clades [nectar groups (NGs) 1, 2 and 3] of nectar pseudomonads, which were closely related to five intrageneric groups: Pseudomonas oryzihabitans (NG 1); P. fluorescens, P. lutea and P. syringae (NG 2); and P. rhizosphaerae (NG 3). Linkage disequilibrium analysis pointed to a mostly clonal population structure, even when the analysis was restricted to isolates from the same floristic region or belonging to the same NG. Nevertheless, signatures of recombination were observed for NG 3, which exclusively included isolates retrieved from the floral nectar of insect-pollinated Mediterranean plants. In contrast, the other two NGs comprised both South African and Mediterranean isolates. Analyses relating diversification to floristic region and pollinator type revealed that there has been more unique evolution of the nectar pseudomonads within the Mediterranean region than would be expected by chance. This is the first work analysing the sequence of multiple loci to reveal geno- and ecotypes of nectar bacteria.

Genetic diversity and structure of Brazilian ginger germplasm (Zingiber officinale) revealed by AFLP markers.

Science.gov (United States)

Blanco, Eleonora Zambrano; Bajay, Miklos Maximiliano; Siqueira, Marcos Vinícius Bohrer Monteiro; Zucchi, Maria Imaculada; Pinheiro, José Baldin

2016-12-01

Ginger is a vegetable with medicinal and culinary properties widely cultivated in the Southern and Southeastern Brazil. The knowledge of ginger species' genetic variability is essential to direct correctly future studies of conservation and genetic improvement, but in Brazil, little is known about this species' genetic variability. In this study, we analyzed the genetic diversity and structure of 55 Brazilian accessions and 6 Colombian accessions of ginger, using AFLP (Amplified Fragment Length Polymorphism) molecular markers. The molecular characterization was based on 13 primers combinations, which generated an average of 113.5 polymorphic loci. The genetic diversity estimates of Nei (Hj), Shannon-Weiner index (I) and an effective number of alleles (n e ) were greater in the Colombian accessions in relation to the Brazilian accessions. The analysis of molecular variance showed that most of the genetic variation occurred between the two countries while in the Brazilian populations there is no genetic structure and probably each region harbors 100 % of genetic variation found in the samples. The bayesian model-based clustering and the dendrogram using the dissimilarity's coefficient of Jaccard were congruent with each other and showed that the Brazilian accessions are highly similar between themselves, regardless of the geographic region of origin. We suggested that the exploration of the interspecific variability and the introduction of new varieties of Z.officinale are viable alternatives for generating diversity in breeding programs in Brazil. The introduction of new genetic materials will certainly contribute to a higher genetic basis of such crop.

Genetic diversity and linkage disequilibrium in Chinese bread wheat (Triticum aestivum L.) revealed by SSR markers.

Science.gov (United States)

Hao, Chenyang; Wang, Lanfen; Ge, Hongmei; Dong, Yuchen; Zhang, Xueyong

2011-02-18

Two hundred and fifty bread wheat lines, mainly Chinese mini core accessions, were assayed for polymorphism and linkage disequilibrium (LD) based on 512 whole-genome microsatellite loci representing a mean marker density of 5.1 cM. A total of 6,724 alleles ranging from 1 to 49 per locus were identified in all collections. The mean PIC value was 0.650, ranging from 0 to 0.965. Population structure and principal coordinate analysis revealed that landraces and modern varieties were two relatively independent genetic sub-groups. Landraces had a higher allelic diversity than modern varieties with respect to both genomes and chromosomes in terms of total number of alleles and allelic richness. 3,833 (57.0%) and 2,788 (41.5%) rare alleles with frequencies of varieties displayed a wider average LD decay across the whole genome for locus pairs with r(2)>0.05 (Pvarieties. LD decay distances were also somewhat different for each of the 21 chromosomes, being higher for most of the chromosomes in modern varieties (<5 ∼ 25 cM) compared to landraces (<5 ∼ 15 cM), presumably indicating the influences of domestication and breeding. This study facilitates predicting the marker density required to effectively associate genotypes with traits in Chinese wheat genetic resources.

Genetic diversity in populations of Isatis glauca Aucher ex Boiss. ssp. from Central Anatolia in Turkey, as revealed by AFLP analysis.

Science.gov (United States)

Özbek, Özlem; Görgülü, Elçin; Yıldırımlı, Şinasi

2013-12-01

Isatidae L. is a complex and systematically difficult genus in Brassicaceae. The genus displays great morphological polymorphism, which makes the classification of species and subspecies difficult as it is observed in Isatis glauca Aucher ex Boiss. The aim of this study is characterization of the genetic diversity in subspecies of Isatis glauca Aucher ex Boiss. distributed widely in Central Anatolia, in Turkey by using Amplified Fragment Length Polymorphism (AFLP) technique. Eight different Eco RI-Mse I primer combinations produced 805 AFLP loci, 793 (98.5%) of which were polymorphic in 67 accessions representing nine different populations. The data obtained by AFLP was computed with using GDA (Genetic Data Analysis) and STRUCTURE (version 2.3.3) software programs for population genetics. The mean proportion of the polymorphic locus (P), the mean number of alleles (A), the number of unique alleles (U) and the mean value of gene diversity (He) were 0.59, 1.59, 20, and 0.23 respectively. The coancestry coefficient (ϴ) was 0.24. The optimal number of K was identified as seven. The principal component analysis (PCA) explained 85.61% of the total genetic variation. Isatis glauca ssp. populations showed a high level of genetic diversity, and the AFLP analysis revealed that high polymorphism and differentiated subspecies could be used conveniently for population genetic studies. The principal coordinate analysis (PCoA) based on the dissimilarity matrix, the dendrogram drawn with UPGMA method and STRUCTURE cluster analysis distinguished the accessions successfully. The accessions formed distinctive population structures for populations AA, AB, E, K, and S. Populations AG1 and AG2 seemed to have similar genetic content, in addition, in both populations several hybrid individuals were observed. The accessions did not formed distinctive population structures for both populations AI and ANP. Consequently, Ankara province might be the area, where species Isatis glauca Aucher

Comprehensive analyses of imprinted differentially methylated regions reveal epigenetic and genetic characteristics in hepatoblastoma

International Nuclear Information System (INIS)

Rumbajan, Janette Mareska; Aoki, Shigehisa; Kohashi, Kenichi; Oda, Yoshinao; Hata, Kenichiro; Saji, Tsutomu; Taguchi, Tomoaki; Tajiri, Tatsuro; Soejima, Hidenobu; Joh, Keiichiro; Maeda, Toshiyuki; Souzaki, Ryota; Mitsui, Kazumasa; Higashimoto, Ken; Nakabayashi, Kazuhiko; Yatsuki, Hitomi; Nishioka, Kenichi; Harada, Ryoko

2013-01-01

Aberrant methylation at imprinted differentially methylated regions (DMRs) in human 11p15.5 has been reported in many tumors including hepatoblastoma. However, the methylation status of imprinted DMRs in imprinted loci scattered through the human genome has not been analyzed yet in any tumors. The methylation statuses of 33 imprinted DMRs were analyzed in 12 hepatoblastomas and adjacent normal liver tissue by MALDI-TOF MS and pyrosequencing. Uniparental disomy (UPD) and copy number abnormalities were investigated with DNA polymorphisms. Among 33 DMRs analyzed, 18 showed aberrant methylation in at least 1 tumor. There was large deviation in the incidence of aberrant methylation among the DMRs. KvDMR1 and IGF2-DMR0 were the most frequently hypomethylated DMRs. INPP5Fv2-DMR and RB1-DMR were hypermethylated with high frequencies. Hypomethylation was observed at certain DMRs not only in tumors but also in a small number of adjacent histologically normal liver tissue, whereas hypermethylation was observed only in tumor samples. The methylation levels of long interspersed nuclear element-1 (LINE-1) did not show large differences between tumor tissue and normal liver controls. Chromosomal abnormalities were also found in some tumors. 11p15.5 and 20q13.3 loci showed the frequent occurrence of both genetic and epigenetic alterations. Our analyses revealed tumor-specific aberrant hypermethylation at some imprinted DMRs in 12 hepatoblastomas with additional suggestion for the possibility of hypomethylation prior to tumor development. Some loci showed both genetic and epigenetic alterations with high frequencies. These findings will aid in understanding the development of hepatoblastoma

Perception, experience, and response to genetic discrimination in Huntington disease: the international RESPOND-HD study.

Science.gov (United States)

Erwin, Cheryl; Williams, Janet K; Juhl, Andrew R; Mengeling, Michelle; Mills, James A; Bombard, Yvonne; Hayden, Michael R; Quaid, Kimberly; Shoulson, Ira; Taylor, Sandra; Paulsen, Jane S

2010-07-01

Genetic discrimination-defined as the denial of rights, privileges, or opportunities or other adverse treatment based solely on genetic information (including family history)-is an important concern to patients, healthcare professionals, lawmakers, and family members at risk for carrying a deleterious gene. Data from the United States, Canada, and Australia were collected from 433 individuals at risk for Huntington disease (HD) who have tested either positive or negative for the gene that causes HD and family members of affected individuals who have a 50% risk for developing the disorder but remain untested. Across all three countries, a total of 46.2% of respondents report genetic discrimination or stigma based on either their family history of HD or genetic testing for the HD gene mutation. We report on the overall incidence of discrimination and stigma in the domains of insurance (25.9%), employment (6.5%), relationships (32.9%), and other transactions (4.6%) in the United States, Canada, and Australia combined. The incidence of self-reported discrimination is less than the overall worry about the risk of discrimination, which is more prevalent in each domain. Despite a relatively low rate of perceived genetic discrimination in the areas of health insurance and employment, compared to the perception of discrimination and stigma in personal relationships, the cumulative burden of genetic discrimination across all domains of experience represents a challenge to those at risk for HD. The effect of this cumulative burden on daily life decisions remains unknown. (c) 2010 Wiley-Liss, Inc.

Genetic programming in microorganisms

Energy Technology Data Exchange (ETDEWEB)

Hopwood, D A

1981-11-01

Formerly, when microbiologists had only existing organisms at their disposal whose characteristics could only be changed randomly by genetic experiments, they used to dream of programmed genetic changes. This dream has come true with modern genetic engineering.

Distinct genetic diversity of Oncomelania hupensis, intermediate host of Schistosoma japonicum in mainland China as revealed by ITS sequences.

Directory of Open Access Journals (Sweden)

Qin Ping Zhao

Full Text Available BACKGROUND: Oncomelania hupensis is the unique intermediate host of Schistosoma japonicum, which causes schistosomiasis endemic in the Far East, and especially in mainland China. O. hupensis largely determines the parasite's geographical range. How O. hupensis's genetic diversity is distributed geographically in mainland China has never been well examined with DNA sequence data. METHODOLOGY/PRINCIPAL FINDINGS: In this study we investigate the genetic variation among O. hupensis from different geographical origins using the combined complete internal transcribed spacer 1 (ITS1 and ITS2 regions of nuclear ribosomal DNA. 165 O. hupensis isolates were obtained in 29 localities from 7 provinces across mainland China: lake/marshland and hill regions in Anhui, Hubei, Hunan, Jiangxi and Jiangsu provinces, located along the middle and lower reaches of Yangtze River, and mountainous regions in Sichuan and Yunnan provinces. Phylogenetic and haplotype network analyses showed distinct genetic diversity and no shared haplotypes between populations from lake/marshland regions of the middle and lower reaches of the Yangtze River and populations from mountainous regions of Sichuan and Yunnan provinces. The genetic distance between these two groups is up to 0.81 based on Fst, and branch time was estimated as 2-6 Ma. As revealed in the phylogenetic tree, snails from Sichuan and Yunnan provinces were also clustered separately. Geographical separation appears to be an important factor accounting for the diversification of the two groups of O. hupensis in mainland China, and probably for the separate clades between snails from Sichuan and Yunnan provinces. In lake/marshland and hill regions along the middle and lower reaches of the Yangtze River, three clades were identified in the phylogenetic tree, but without any obvious clustering of snails from different provinces. CONCLUSIONS: O. hupensis in mainland China may have considerable genetic diversity, and a more

A genome wide survey of SNP variation reveals the genetic structure of sheep breeds.

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James W Kijas

Full Text Available The genetic structure of sheep reflects their domestication and subsequent formation into discrete breeds. Understanding genetic structure is essential for achieving genetic improvement through genome-wide association studies, genomic selection and the dissection of quantitative traits. After identifying the first genome-wide set of SNP for sheep, we report on levels of genetic variability both within and between a diverse sample of ovine populations. Then, using cluster analysis and the partitioning of genetic variation, we demonstrate sheep are characterised by weak phylogeographic structure, overlapping genetic similarity and generally low differentiation which is consistent with their short evolutionary history. The degree of population substructure was, however, sufficient to cluster individuals based on geographic origin and known breed history. Specifically, African and Asian populations clustered separately from breeds of European origin sampled from Australia, New Zealand, Europe and North America. Furthermore, we demonstrate the presence of stratification within some, but not all, ovine breeds. The results emphasize that careful documentation of genetic structure will be an essential prerequisite when mapping the genetic basis of complex traits. Furthermore, the identification of a subset of SNP able to assign individuals into broad groupings demonstrates even a small panel of markers may be suitable for applications such as traceability.

The genetic structure of Turnip mosaic virus population reveals the rapid expansion of a new emergent lineage in China.

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Li, Xiangdong; Zhu, Tiansheng; Yin, Xiao; Zhang, Chengling; Chen, Jia; Tian, Yanping; Liu, Jinliang

2017-08-29

Turnip mosaic virus (TuMV) is one of the most widespread and economically important virus infecting both crop and ornamental species of the family Brassicaceae. TuMV isolates can be classified to five phylogenetic lineages, basal-B, basal-BR, Asian-BR, world-B and Orchis. To understand the genetic structure of TuMV from radish in China, the 3'-terminal genome of 90 TuMV isolates were determined and analyzed with other available Chinese isolates. The results showed that the Chinese TuMV isolates from radish formed three groups: Asian-BR, basal-BR and world-B. More than half of these isolates (52.54%) were clustered to basal-BR group, and could be further divided into three sub-groups. The TuMV basal-BR isolates in the sub-groups I and II were genetically homologous with Japanese ones, while those in sub-group III formed a distinct lineage. Sub-populations of TuMV basal-BR II and III were new emergent and in a state of expansion. The Chinese TuMV radish populations were under negative selection. Gene flow between TuMV populations from Tai'an, Weifang and Changchun was frequent. The genetic structure of Turnip mosaic virus population reveals the rapid expansion of a new emergent lineage in China.

Population genetic analysis of Colombian Trypanosoma cruzi isolates revealed by enzyme electrophoretic profiles

OpenAIRE

Ruiz-Garcia, Manuel; Montilla, Marleny; Nicholls, Sebastian; Alvarez, Diana

2001-01-01

Although Colombia presents an enormous biological diversity, few studies have been conducted on the population genetics of Trypanosoma cruzi. This study was carried out with 23 Colombian stocks of this protozoa analyzed for 13 isoenzymatic loci. The Hardy-Weinberg equilibrium, the genetic diversity and heterogeneity, the genetic relationships and the possible spatial structure of these 23 Colombian stocks of T. cruzi were estimated. The majority of results obtained are in agreement with a clo...

Genetic networks of liver metabolism revealed by integration of metabolic and transcriptional profiling.

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Christine T Ferrara

2008-03-01

Full Text Available Although numerous quantitative trait loci (QTL influencing disease-related phenotypes have been detected through gene mapping and positional cloning, identification of the individual gene(s and molecular pathways leading to those phenotypes is often elusive. One way to improve understanding of genetic architecture is to classify phenotypes in greater depth by including transcriptional and metabolic profiling. In the current study, we have generated and analyzed mRNA expression and metabolic profiles in liver samples obtained in an F2 intercross between the diabetes-resistant C57BL/6 leptin(ob/ob and the diabetes-susceptible BTBR leptin(ob/ob mouse strains. This cross, which segregates for genotype and physiological traits, was previously used to identify several diabetes-related QTL. Our current investigation includes microarray analysis of over 40,000 probe sets, plus quantitative mass spectrometry-based measurements of sixty-seven intermediary metabolites in three different classes (amino acids, organic acids, and acyl-carnitines. We show that liver metabolites map to distinct genetic regions, thereby indicating that tissue metabolites are heritable. We also demonstrate that genomic analysis can be integrated with liver mRNA expression and metabolite profiling data to construct causal networks for control of specific metabolic processes in liver. As a proof of principle of the practical significance of this integrative approach, we illustrate the construction of a specific causal network that links gene expression and metabolic changes in the context of glutamate metabolism, and demonstrate its validity by showing that genes in the network respond to changes in glutamine and glutamate availability. Thus, the methods described here have the potential to reveal regulatory networks that contribute to chronic, complex, and highly prevalent diseases and conditions such as obesity and diabetes.

Studies on nonsense mediated decay reveal novel therapeutic options for genetic diseases.

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Bashyam, Murali D

2009-01-01

Scientific breakthroughs have often led to commercially viable patents mainly in the field of engineering. Commercialization in the field of medicine has been restricted mostly to machinery and engineering on the one hand and therapeutic drugs for common chronic ailments such as cough, cold, headache, etc, on the other. Sequencing of the human genome has attracted the attention of pharmaceutical companies and now biotechnology has become a goldmine for commercialization of products and processes. Recent advances in our understanding of basic biological processes have resulted in the opening of new avenues for treatment of human genetic diseases, especially single gene disorders. A significant proportion of human genetic disorders have been shown to be caused due to degradation of transcripts for specific genes through a process called nonsense mediated decay (NMD). The modulation of NMD provides a viable therapeutic option for treatment of several genetic disorders and therefore has been a good prospect for patenting and commercialization. In this review the molecular basis for NMD and attempts to treat genetic diseases which result from NMD are discussed.

A chemical-genetic strategy reveals distinct temporal requirements for SAD-1 kinase in neuronal polarization and synapse formation

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Shokat Kevan M

2008-09-01

Full Text Available Abstract Background Neurons assemble into a functional network through a sequence of developmental processes including neuronal polarization and synapse formation. In Caenorhabditis elegans, the serine/threonine SAD-1 kinase is essential for proper neuronal polarity and synaptic organization. To determine if SAD-1 activity regulates the establishment or maintenance of these neuronal structures, we examined its temporal requirements using a chemical-genetic method that allows for selective and reversible inactivation of its kinase activity in vivo. Results We generated a PP1 analog-sensitive variant of SAD-1. Through temporal inhibition of SAD-1 kinase activity we show that its activity is required for the establishment of both neuronal polarity and synaptic organization. However, while SAD-1 activity is needed strictly when neurons are polarizing, the temporal requirement for SAD-1 is less stringent in synaptic organization, which can also be re-established during maintenance. Conclusion This study reports the first temporal analysis of a neural kinase activity using the chemical-genetic system. It reveals that neuronal polarity and synaptic organization have distinct temporal requirements for SAD-1.

The Genetics of Autoimmune Thyroiditis: the first decade

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Rose, Noel R.

2011-01-01

Most of our current understanding of the genetic predisposition to autoimmune disease can be traced to experiments performed in the decade from 1971 to 1981. Chella David was a key contributor to this research. Many of these early steps came from studies of experimental autoimmune thyroiditis. This model has been especially valuable because essentially the same disease can occur spontaneously in selected strains of animals or can be induced by deliberate immunization. From a genetic point of view, the disease has been investigated in three different species: mice, rats and chickens. The same antigen, thyroglobulin, initiates the disease in all three species. Among the main discoveries were the relationship of autoimmune disease to the major histocompatibility complex (MHC), the interplay of different subregions within the MHC in promoting or retarding development of disease, the differing roles of MHC class II and MHC I class genes in induction and effector phases, respectively, and the cumulative effect of non-MHC genes, each of which represents a small addition to overall susceptibility. Other experiments revealed that genetic differences in thyroglobulin allotypes influence susceptibility to thyroiditis. Thyroid glands differed in different strains in vulnerability to passive transfer of antibody. The first evidence of modulatory genes on the sex-related X chromosome emerged. All of these genetic findings were concurrently translated to the human disease, Hashimoto’s thyroiditis, where thyroglobulin is also the initiating antigen. PMID:21683550

Preimplantation genetic diagnosis for cystic fibrosis: the Montpellier center's 10-year experience.

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Girardet, A; Ishmukhametova, A; Willems, M; Coubes, C; Hamamah, S; Anahory, T; Des Georges, M; Claustres, M

2015-02-01

This study provides an overview of 10 years of experience of preimplantation genetic diagnosis (PGD) for cystic fibrosis (CF) in our center. Owing to the high allelic heterogeneity of CF transmembrane conductance regulator (CFTR) mutations in south of France, we have set up a powerful universal test based on haplotyping eight short tandem repeats (STR) markers together with the major mutation p.Phe508del. Of 142 couples requesting PGD for CF, 76 have been so far enrolled in the genetic work-up, and 53 had 114 PGD cycles performed. Twenty-nine cycles were canceled upon in vitro fertilization (IVF) treatment because of hyper- or hypostimulation. Of the remaining 85 cycles, a total of 493 embryos were biopsied and a genetic diagnosis was obtained in 463 (93.9%), of which 262 (without or with a single CF-causing mutation) were transferable. Twenty-eight clinical pregnancies were established, yielding a pregnancy rate per transfer of 30.8% in the group of seven couples with one member affected with CF, and 38.3% in the group of couples whose both members are carriers of a CF-causing mutation [including six couples with congenital bilateral absence of the vas deferens (CBAVD)]. So far, 25 children were born free of CF and no misdiagnosis was recorded. Our test is applicable to 98% of couples at risk of transmitting CF. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Genome sequencing reveals a new lineage associated with lablab bean and genetic exchange between Xanthomonas axonopodis pv. phaseoli and Xanthomonas fuscans subsp. fuscans

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Valente eAritua

2015-10-01

Full Text Available Common bacterial blight is a devastating seed-borne disease of common beans that also occurs on other legume species including lablab and Lima beans. We sequenced and analysed the genomes of 26 isolates of Xanthomonas axonopodis pv. phaseoli and X. fuscans subsp. fuscans, the causative agents of this disease, collected over four decades and six continents. This revealed considerable genetic variation within both taxa, encompassing both single-nucleotide variants and differences in gene content, that could be exploited for tracking pathogen spread. The bacterial isolate from Lima bean fell within the previously described Genetic Lineage 1, along with the pathovar type isolate (NCPPB 3035. The isolates from lablab represent a new, previously unknown genetic lineage closely related to strains of X. axonopodis pv. glycines. Finally, we identified more than 100 genes that appear to have been recently acquired by Xanthomonas axonopodis pv. phaseoli from X. fuscans subsp. fuscans.

Genetic variability, heritability and genetic advance of quantitative ...

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ONOS

2010-05-10

May 10, 2010 ... coefficient of variation; h2, heritability; GA, genetic advance;. EMS, ethyl methane ... The analysis of variance (ANOVA) revealed the significance degree among the ... fullest extent. The estimates of range, phenotypic and.

Targeted Genetic Screen in Amyotrophic Lateral Sclerosis Reveals Novel Genetic Variants with Synergistic Effect on Clinical Phenotype

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Johnathan Cooper-Knock

2017-11-01

Full Text Available Amyotrophic lateral sclerosis (ALS is underpinned by an oligogenic rare variant architecture. Identified genetic variants of ALS include RNA-binding proteins containing prion-like domains (PrLDs. We hypothesized that screening genes encoding additional similar proteins will yield novel genetic causes of ALS. The most common genetic variant of ALS patients is a G4C2-repeat expansion within C9ORF72. We have shown that G4C2-repeat RNA sequesters RNA-binding proteins. A logical consequence of this is that loss-of-function mutations in G4C2-binding partners might contribute to ALS pathogenesis independently of and/or synergistically with C9ORF72 expansions. Targeted sequencing of genomic DNA encoding either RNA-binding proteins or known ALS genes (n = 274 genes was performed in ALS patients to identify rare deleterious genetic variants and explore genotype-phenotype relationships. Genomic DNA was extracted from 103 ALS patients including 42 familial ALS patients and 61 young-onset (average age of onset 41 years sporadic ALS patients; patients were chosen to maximize the probability of identifying genetic causes of ALS. Thirteen patients carried a G4C2-repeat expansion of C9ORF72. We identified 42 patients with rare deleterious variants; 6 patients carried more than one variant. Twelve mutations were discovered in known ALS genes which served as a validation of our strategy. Rare deleterious variants in RNA-binding proteins were significantly enriched in ALS patients compared to control frequencies (p = 5.31E-18. Nineteen patients featured at least one variant in a RNA-binding protein containing a PrLD. The number of variants per patient correlated with rate of disease progression (t-test, p = 0.033. We identified eighteen patients with a single variant in a G4C2-repeat binding protein. Patients with a G4C2-binding protein variant in combination with a C9ORF72 expansion had a significantly faster disease course (t-test, p = 0.025. Our data are

The genetic diversity of the mangrove kandelia obovata in China revealed by ISSR analysis

International Nuclear Information System (INIS)

Chen, Shao-Bo; Ding, When-Young; Qiu, Jia-Biao; Wang, Guang-Yin; Zhou, Zhi-Min; Chen- Jiao-Fei; Ai, Wewi-ming; Wang, Cheng-Yi; Xie, Qi-Lang

2010-01-01

The genetic diversity of 7 populations of Kandelia obovata in China was characterized using inter simple sequence repeats (ISSR) technique. A total of 50 primers were screened, of which 9 polymorphic and informative patterns were selected to determine genetic relationships. ISSR amplification was conducted on 140 individuals from 7 populations, and 88 polymorphic loci were detected from 106 total loci. The total percentage of polymorphic loci (PPL) was 83.02%. The percentage of PPL at the population level ranged from 32.08% to 47.17%, with an average of 39.89%. Nei's gene diversity (H) and Shannon's information index (I) of K. obovata at the species level were 0.3631 and 0.5203, respectively. The genetic differentiation coefficient (Gst) among populations was 0.5548. Among populations component accounted for 55.48% of the total variation, whereas the within populations component accounted for 44.52%, suggesting that genetic differentiation among K. obovata populations was relatively high. The gene flow among populations was 0.4012, indicating that gene flow was low among geographically diverse populations of K. obovata. The results of the genetic diversity and cluster analysis suggest that geographical isolation of K. obovata populations mainly results in low gene flow and random genetic drift, leading to genetic differentiation. (author)

Competitive advantage and higher fitness in native populations of genetically structured planktonic diatoms.

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Sildever, Sirje; Sefbom, Josefin; Lips, Inga; Godhe, Anna

2016-12-01

It has been shown that the planktonic diatom Skeletonema from neighbouring areas are genetically differentiated despite absence of physical dispersal barriers. We revisited two sites, Mariager Fjord and Kattegat, NE Atlantic, and isolated new strains. Microsatellite genotyping and F-statistics revealed that the populations were genetically differentiated. An experiment was designed to investigate if populations are locally adapted and have a native competitive advantage. Ten strains from each location were grown individually in native and foreign water to investigate differences in produced biomass. Additionally, we mixed six pairs, one strain from each site, and let them grow together in native and foreign water. Strains from Mariager Fjord and Kattegat produced higher biomass in native water. In the competition experiment, strains from both sites displayed higher relative abundance and demonstrated competitive advantage in their native water. The cause of the differentiated growth is unknown, but could possibly be attributed to differences in silica concentration or viruses in the two water types. Our data show that dispersal potential does not influence the genetic structure of the populations. We conclude that genetic adaptation has not been overruled by gene flow, but instead the responses to different selection conditions are enforcing the observed genetic structure. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

The evidence base regarding the experiences of and attitudes to preimplantation genetic diagnosis in prospective parents.

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Cunningham, Jenny; Goldsmith, Lesley; Skirton, Heather

2015-02-01

Preimplantation genetic diagnosis was developed as an alternative to prenatal diagnosis for couples with a family history of genetic disease. After in vitro fertilization, the embryos can be analysed to ensure that only healthy embryos are transferred to the uterus. Past studies have suggested that couples who wish to avoid having a child with an inherited genetic condition look favourably on preimplantation genetic diagnosis as it prevents the need for termination of pregnancy following prenatal diagnosis of an affected fetus. However, it is important to understand the experiences of couples who have used or consider using this technique. To ascertain the current evidence base on this topic, we conducted a mixed methods systematic review. Four databases were searched for relevant peer-reviewed papers published between 2000 and 2013. Of 453 papers, nine satisfied the inclusion criteria and were assessed for quality. Results of nine papers were analysed and synthesised using a narrative approach. Three main themes emerged: (1) motivating factors; (2) emotional labour; (3) choices and uncertainty. The review has identified an emotional and difficult journey for couples pursuing preimplantation genetic diagnosis. While use of the technique gives hope to families who wish to prevent transmission of a genetic disease this is not without hard decision-making and periods of uncertainty. Lack of information was perceived as a barrier to access this reproductive option. Recommendations include: training and education in genetics for midwives who are the first point of contact for pregnant women; clinics to use a decision-making tool to emphasise the uncertainty involved in PGD and improved communication and psychological support to couples. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization of the active microbiotas associated with honey bees reveals healthier and broader communities when colonies are genetically diverse.

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Heather R Mattila

Full Text Available Recent losses of honey bee colonies have led to increased interest in the microbial communities that are associated with these important pollinators. A critical function that bacteria perform for their honey bee hosts, but one that is poorly understood, is the transformation of worker-collected pollen into bee bread, a nutritious food product that can be stored for long periods in colonies. We used 16S rRNA pyrosequencing to comprehensively characterize in genetically diverse and genetically uniform colonies the active bacterial communities that are found on honey bees, in their digestive tracts, and in bee bread. This method provided insights that have not been revealed by past studies into the content and benefits of honey bee-associated microbial communities. Colony microbiotas differed substantially between sampling environments and were dominated by several anaerobic bacterial genera never before associated with honey bees, but renowned for their use by humans to ferment food. Colonies with genetically diverse populations of workers, a result of the highly promiscuous mating behavior of queens, benefited from greater microbial diversity, reduced pathogen loads, and increased abundance of putatively helpful bacteria, particularly species from the potentially probiotic genus Bifidobacterium. Across all colonies, Bifidobacterium activity was negatively correlated with the activity of genera that include pathogenic microbes; this relationship suggests a possible target for understanding whether microbes provide protective benefits to honey bees. Within-colony diversity shapes microbiotas associated with honey bees in ways that may have important repercussions for colony function and health. Our findings illuminate the importance of honey bee-bacteria symbioses and examine their intersection with nutrition, pathogen load, and genetic diversity, factors that are considered key to understanding honey bee decline.

Genetic diversity of Clavispora lusitaniae isolated from Agave fourcroydes Lem, as revealed by DNA fingerprinting.

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Pérez-Brito, Daisy; Magaña-Alvarez, Anuar; Lappe-Oliveras, Patricia; Cortes-Velazquez, Alberto; Torres-Calzada, Claudia; Herrera-Suarez, Teófilo; Larqué-Saavedra, Alfonso; Tapia-Tussell, Raul

2015-01-01

This study characterized Clavispora lusitaniae strains isolated from different stages of the processing and early fermentation of a henequen (Agave fourcroydes) spirit produced in Yucatan, Mexico using a molecular technique. Sixteen strains identified based on morphological features, obtained from different substrates, were typed molecularly. Nine different versions of the divergent D1/D2 domain of the large-subunit ribosomal DNA sequence were identified among the C. lusitaniae strains. The greatest degree of polymorphism was found in the 90-bp structural motif of the D2 domain. The MSP-PCR technique was able to differentiate 100% of the isolates. This study provides significant insight into the genetic diversity of the mycobiota present during the henequen fermentation process, especially that of C. lusitaniae, for which only a few studies in plants have been published. The applied MSP-PCR markers were very efficient in revealing olymorphisms between isolates of this species.

Genetic characterization of Toxoplasma gondii isolates from Portugal, Austria, and Israel reveals higher genetic variability within the type II lineage

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This study compared genetic diversity of Toxoplasma gondii isolates from Portugal, Austria and Israel. For this, we genotyped 90 T. gondii isolates (16 from Portugal, 67 from Austria and 7 from Israel) using 10 nested PCR-restriction length polymorphism (RFLP) genetic markers and 15 microsatellite (...

Genetic evidence for gonochoristic reproduction in gynogenetic silver crucian carp (Carassius auratus gibelio bloch) as revealed by RAPD assays.

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Zhou, L; Wang, Y; Gui, J F

2000-11-01

Sex evolution has been a debating focus in evolutionary genetics. In lower vertebrates of reptiles, amphibians, and fish, a species or a bioform reproduces either sexually or asexually but never both. A few species were found to consist of all females in fish. These all-female species can propagate by asexual reproduction modes, such as gynogenesis and hybridogenesis. However, the coexistence of sexuality and asexuality in a single species was recently noted only in a cyprinid fish silver crucian carp, Carassius auratus gibelio. This fish had been demonstrated to be capable of gynogenesis stimulated by sperm from other related species. Surprisingly, natural populations of this fish consist of a minor but significant portion (approx. 20%) of males. As different clones with specific phenotypic and genetic characteristics have been found, and RAPD markers specific to each clone have recently been identified, this fish offers many advantages for analyzing whether or not genetic recombination occurs between different clones. In this study, artificial propagation was performed in clone F and clone D. Ovulated eggs from clone F were divided into two parts and respectively inseminated with sperm from a clone D male and from a red common carp (Cyprinus carpio) male. The control clone D individuals were selected from gynogenetic offspring of clone D activated by sperm of red common carp. The phenotype and sex ratio in the experimental groups were also observed. Using RAPD molecular markers, which allow for reliable discrimination and genetic analysis of different clones, we have revealed direct molecular evidence for gonochoristic reproduction in the gynogenetic silver crucian carp and confirmed a previous hypothesis that the silver crucian carp might reproduce both gynogenetically and gonochoristically. Therefore, we conclude that the silver crucian carp possesses two reproductive modes, i.e., gynogenetic and gonochoristic reproduction. The response mechanism of two

Landscape genetic analyses reveal fine-scale effects of forest fragmentation in an insular tropical bird.

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Khimoun, Aurélie; Peterman, William; Eraud, Cyril; Faivre, Bruno; Navarro, Nicolas; Garnier, Stéphane

2017-10-01

Within the framework of landscape genetics, resistance surface modelling is particularly relevant to explicitly test competing hypotheses about landscape effects on gene flow. To investigate how fragmentation of tropical forest affects population connectivity in a forest specialist bird species, we optimized resistance surfaces without a priori specification, using least-cost (LCP) or resistance (IBR) distances. We implemented a two-step procedure in order (i) to objectively define the landscape thematic resolution (level of detail in classification scheme to describe landscape variables) and spatial extent (area within the landscape boundaries) and then (ii) to test the relative role of several landscape features (elevation, roads, land cover) in genetic differentiation in the Plumbeous Warbler (Setophaga plumbea). We detected a small-scale reduction of gene flow mainly driven by land cover, with a negative impact of the nonforest matrix on landscape functional connectivity. However, matrix components did not equally constrain gene flow, as their conductivity increased with increasing structural similarity with forest habitat: urban areas and meadows had the highest resistance values whereas agricultural areas had intermediate resistance values. Our results revealed a higher performance of IBR compared to LCP in explaining gene flow, reflecting suboptimal movements across this human-modified landscape, challenging the common use of LCP to design habitat corridors and advocating for a broader use of circuit theory modelling. Finally, our results emphasize the need for an objective definition of landscape scales (landscape extent and thematic resolution) and highlight potential pitfalls associated with parameterization of resistance surfaces. © 2017 John Wiley & Sons Ltd.

Genetic signatures of adaptation revealed from transcriptome sequencing of Arctic and red foxes.

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Kumar, Vikas; Kutschera, Verena E; Nilsson, Maria A; Janke, Axel

2015-08-07

The genus Vulpes (true foxes) comprises numerous species that inhabit a wide range of habitats and climatic conditions, including one species, the Arctic fox (Vulpes lagopus) which is adapted to the arctic region. A close relative to the Arctic fox, the red fox (Vulpes vulpes), occurs in subarctic to subtropical habitats. To study the genetic basis of their adaptations to different environments, transcriptome sequences from two Arctic foxes and one red fox individual were generated and analyzed for signatures of positive selection. In addition, the data allowed for a phylogenetic analysis and divergence time estimate between the two fox species. The de novo assembly of reads resulted in more than 160,000 contigs/transcripts per individual. Approximately 17,000 homologous genes were identified using human and the non-redundant databases. Positive selection analyses revealed several genes involved in various metabolic and molecular processes such as energy metabolism, cardiac gene regulation, apoptosis and blood coagulation to be under positive selection in foxes. Branch site tests identified four genes to be under positive selection in the Arctic fox transcriptome, two of which are fat metabolism genes. In the red fox transcriptome eight genes are under positive selection, including molecular process genes, notably genes involved in ATP metabolism. Analysis of the three transcriptomes and five Sanger re-sequenced genes in additional individuals identified a lower genetic variability within Arctic foxes compared to red foxes, which is consistent with distribution range differences and demographic responses to past climatic fluctuations. A phylogenomic analysis estimated that the Arctic and red fox lineages diverged about three million years ago. Transcriptome data are an economic way to generate genomic resources for evolutionary studies. Despite not representing an entire genome, this transcriptome analysis identified numerous genes that are relevant to arctic

Phenylketonuria Genetic Screening Simulation

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Erickson, Patti

2012-01-01

After agreeing to host over 200 students on a daylong genetics field trip, the author needed an easy-to-prepare genetics experiment to accompany the DNA-necklace and gel-electrophoresis activities already planned. One of the student's mothers is a pediatric physician at the local hospital, and she suggested exploring genetic-disease screening…

Analysis of biostimulated microbial communities from two field experiments reveals temporal and spatial differences in proteome profiles

Energy Technology Data Exchange (ETDEWEB)

Callister, S.J.; Wilkins, M.J.; Nicora, C.D.; Williams, K.H.; Banfield, J.F.; VerBerkmoes, N.C.; Hettich, R.L.; NGuessan, A.L.; Mouser, P.J.; Elifantz, H.; Smith, R.D.; Lovley, D.R.; Lipton, M.S.; Long, P.E.

2010-07-15

Stimulated by an acetate-amendment field experiment conducted in 2007, anaerobic microbial populations in the aquifer at the Rifle Integrated Field Research Challenge site in Colorado reduced mobile U(VI) to insoluble U(IV). During this experiment, planktonic biomass was sampled at various time points to quantitatively evaluate proteomes. In 2008, an acetate-amended field experiment was again conducted in a similar manner to the 2007 experiment. As there was no comprehensive metagenome sequence available for use in proteomics analysis, we systematically evaluated 12 different organism genome sequences to generate sets of aggregate genomes, or “pseudo-metagenomes”, for supplying relative quantitative peptide and protein identifications. Proteomics results support previous observations of the dominance of Geobacteraceae during biostimulation using acetate as sole electron donor, and revealed a shift from an early stage of iron reduction to a late stage of iron reduction. Additionally, a shift from iron reduction to sulfate reduction was indicated by changes in the contribution of proteome information contributed by different organism genome sequences within the aggregate set. In addition, the comparison of proteome measurements made between the 2007 field experiment and 2008 field experiment revealed differences in proteome profiles. These differences may be the result of alterations in abundance and population structure within the planktonic biomass samples collected for analysis.

Comparative transcriptome analysis reveals the genetic basis of skin color variation in common carp.

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Yanliang Jiang

Full Text Available The common carp is an important aquaculture species that is widely distributed across the world. During the long history of carp domestication, numerous carp strains with diverse skin colors have been established. Skin color is used as a visual criterion to determine the market value of carp. However, the genetic basis of common carp skin color has not been extensively studied.In this study, we performed Illumina sequencing on two common carp strains: the reddish Xingguo red carp and the brownish-black Yellow River carp. A total of 435,348,868 reads were generated, resulting in 198,781 assembled contigs that were used as reference sequences. Comparisons of skin transcriptome files revealed 2,012 unigenes with significantly different expression in the two common carp strains, including 874 genes that were up-regulated in Xingguo red carp and 1,138 genes that were up-regulated in Yellow River carp. The expression patterns of 20 randomly selected differentially expressed genes were validated using quantitative RT-PCR. Gene pathway analysis of the differentially expressed genes indicated that melanin biosynthesis, along with the Wnt and MAPK signaling pathways, is highly likely to affect the skin pigmentation process. Several key genes involved in the skin pigmentation process, including TYRP1, SILV, ASIP and xCT, showed significant differences in their expression patterns between the two strains.In this study, we conducted a comparative transcriptome analysis of Xingguo red carp and Yellow River carp skins, and we detected key genes involved in the common carp skin pigmentation process. We propose that common carp skin pigmentation depends upon at least three pathways. Understanding fish skin color genetics will facilitate future molecular selection of the fish skin colors with high market values.

Comparative transcriptome analysis reveals the genetic basis of skin color variation in common carp.

Science.gov (United States)

Jiang, Yanliang; Zhang, Songhao; Xu, Jian; Feng, Jianxin; Mahboob, Shahid; Al-Ghanim, Khalid A; Sun, Xiaowen; Xu, Peng

2014-01-01

The common carp is an important aquaculture species that is widely distributed across the world. During the long history of carp domestication, numerous carp strains with diverse skin colors have been established. Skin color is used as a visual criterion to determine the market value of carp. However, the genetic basis of common carp skin color has not been extensively studied. In this study, we performed Illumina sequencing on two common carp strains: the reddish Xingguo red carp and the brownish-black Yellow River carp. A total of 435,348,868 reads were generated, resulting in 198,781 assembled contigs that were used as reference sequences. Comparisons of skin transcriptome files revealed 2,012 unigenes with significantly different expression in the two common carp strains, including 874 genes that were up-regulated in Xingguo red carp and 1,138 genes that were up-regulated in Yellow River carp. The expression patterns of 20 randomly selected differentially expressed genes were validated using quantitative RT-PCR. Gene pathway analysis of the differentially expressed genes indicated that melanin biosynthesis, along with the Wnt and MAPK signaling pathways, is highly likely to affect the skin pigmentation process. Several key genes involved in the skin pigmentation process, including TYRP1, SILV, ASIP and xCT, showed significant differences in their expression patterns between the two strains. In this study, we conducted a comparative transcriptome analysis of Xingguo red carp and Yellow River carp skins, and we detected key genes involved in the common carp skin pigmentation process. We propose that common carp skin pigmentation depends upon at least three pathways. Understanding fish skin color genetics will facilitate future molecular selection of the fish skin colors with high market values.

Reveal, A General Reverse Engineering Algorithm for Inference of Genetic Network Architectures

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Liang, Shoudan; Fuhrman, Stefanie; Somogyi, Roland

1998-01-01

Given the immanent gene expression mapping covering whole genomes during development, health and disease, we seek computational methods to maximize functional inference from such large data sets. Is it possible, in principle, to completely infer a complex regulatory network architecture from input/output patterns of its variables? We investigated this possibility using binary models of genetic networks. Trajectories, or state transition tables of Boolean nets, resemble time series of gene expression. By systematically analyzing the mutual information between input states and output states, one is able to infer the sets of input elements controlling each element or gene in the network. This process is unequivocal and exact for complete state transition tables. We implemented this REVerse Engineering ALgorithm (REVEAL) in a C program, and found the problem to be tractable within the conditions tested so far. For n = 50 (elements) and k = 3 (inputs per element), the analysis of incomplete state transition tables (100 state transition pairs out of a possible 10(exp 15)) reliably produced the original rule and wiring sets. While this study is limited to synchronous Boolean networks, the algorithm is generalizable to include multi-state models, essentially allowing direct application to realistic biological data sets. The ability to adequately solve the inverse problem may enable in-depth analysis of complex dynamic systems in biology and other fields.

Genetic genealogy reveals true Y haplogroup of House of Bourbon contradicting recent identification of the presumed remains of two French Kings.

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Larmuseau, Maarten H D; Delorme, Philippe; Germain, Patrick; Vanderheyden, Nancy; Gilissen, Anja; Van Geystelen, Anneleen; Cassiman, Jean-Jacques; Decorte, Ronny

2014-05-01

Genetic analysis strongly increases the opportunity to identify skeletal remains or other biological samples from historical figures. However, validation of this identification is essential and should be done by DNA typing of living relatives. Based on the similarity of a limited set of Y-STRs, a blood sample and a head were recently identified as those belonging respectively to King Louis XVI and his paternal ancestor King Henry IV. Here, we collected DNA samples from three living males of the House of Bourbon to validate the since then controversial identification of these remains. The three living relatives revealed the Bourbon's Y-chromosomal variant on a high phylogenetic resolution for several members of the lineage between Henry IV and Louis XVI. This 'true' Bourbon's variant is different from the published Y-STR profiles of the blood as well as of the head. The earlier identifications of these samples can therefore not be validated. Moreover, matrilineal genealogical data revealed that the published mtDNA sequence of the head was also different from the one of a series of relatives. This therefore leads to the conclusion that the analyzed samples were not from the French kings. Our study once again demonstrated that in order to realize an accurate genetic identification of historical remains DNA typing of living persons, who are paternally or maternally related with the presumed donor of the samples, is required.

The behavioral genetics of nonhuman primates: Status and prospects.

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Rogers, Jeffrey

2018-01-01

The complexity and diversity of primate behavior have long attracted the attention of ethologists, psychologists, behavioral ecologists, and neuroscientists. Recent studies have advanced our understanding of the nature of genetic influences on differences in behavior among individuals within species. A number of analyses have focused on the genetic analysis of behavioral reactions to specific experimental tests, providing estimates of the degree of genetic control over reactivity, and beginning to identify the genes involved. Substantial progress is also being made in identifying genetic factors that influence the structure and function of the primate brain. Most of the published studies on these topics have examined either cercopithecines or chimpanzees, though a few studies have addressed these questions in other primate species. One potentially important line of research is beginning to identify the epigenetic processes that influence primate behavior, thus revealing specific cellular and molecular mechanisms by which environmental experiences can influence gene expression or gene function relevant to behavior. This review summarizes many of these studies of non-human primate behavioral genetics. The primary focus is on analyses that address the nature of the genes and genetic processes that affect differences in behavior among individuals within non-human primate species. Analyses of between species differences and potential avenues for future research are also discussed. © 2018 American Association of Physical Anthropologists.

Genetic variability of genital mycoplasmas and its clinical value

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K. I. Plakhova

2015-01-01

Full Text Available The article presents data on genetic variability of genital mycoplasmas. The author presents the results of genetic variability studies for M. hominis, gene vaa, U. parvum, gene mba, and M. genitalium, gene mg192, sampled from women with different clinical manifestations of inflammatory diseases of the urogenital system. Based on the molecular typing results for 138 samples of genital mycoplasmas, the author revealed a relationship between clinical manifestations of inflammatory diseases of the urogenital system caused by U. parvum and different U. parvum serovars as well as different genetic variations of M. hominis.Infection with 6 U. parvum serovar results in the development of inflammatory diseases of the urogenital tract accompanied by subjective manifestations (р < 0.05. Genetic variant II of М. hominis was revealed more often in patients with clinical manifestations of inflammatory diseases while variant I was revealed more often in patients infected with М. hominis without any signs of inflammation (р < 0.05. Genetic variants of M. genitalium were determined; no significant differences in terms of their prevalence in the examined patients were revealed.

Haplotype structure around Bru1 reveals a narrow genetic basis for brown rust resistance in modern sugarcane cultivars.

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Costet, L; Le Cunff, L; Royaert, S; Raboin, L-M; Hervouet, C; Toubi, L; Telismart, H; Garsmeur, O; Rousselle, Y; Pauquet, J; Nibouche, S; Glaszmann, J-C; Hoarau, J-Y; D'Hont, A

2012-09-01

Modern sugarcane cultivars (Saccharum spp., 2n = 100-130) are high polyploid, aneuploid and of interspecific origin. A major gene (Bru1) conferring resistance to brown rust, caused by the fungus Puccinia melanocephala, has been identified in cultivar R570. We analyzed 380 modern cultivars and breeding materials covering the worldwide diversity with 22 molecular markers genetically linked to Bru1 in R570 within a 8.2 cM segment. Our results revealed a strong LD in the Bru1 region and strong associations between most of the markers and rust resistance. Two PCR markers, that flank the Bru1-bearing segment, were found completely associated with one another and only in resistant clones representing efficient molecular diagnostic for Bru1. On this basis, Bru1 was inferred in 86 % of the 194 resistant sugarcane accessions, revealing that it constitutes the main source of brown rust resistance in modern cultivars. Bru1 PCR diagnostic markers should be particularly useful to identify cultivars with potentially alternative sources of resistance to diversify the basis of brown rust resistance in breeding programs.

Genetic design of pigs as experimental models in the combat between chronic diseases and healthy aging

DEFF Research Database (Denmark)

Bolund, Lars

2012-01-01

with and without intervention. The genome of different pig breeds have been sequenced, revealing that the pig is genetically more similar to man than conventional laboratory animals - in agreement with the similarities in organ development, physiology and metabolism. Genetically designed minipigs (Göttingen...... pigs. We can also produce clones of pigs, some disease prone and some fluorescing, to perform experiments in regenerative medicine where the fate of healthy fluorescent cells can be followed in the, basically identical, disease prone animals. It is also our hope that our pig models can contribute...

Genetic approaches in comparative and evolutionary physiology

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Bridgham, Jamie T.; Kelly, Scott A.; Garland, Theodore

2015-01-01

Whole animal physiological performance is highly polygenic and highly plastic, and the same is generally true for the many subordinate traits that underlie performance capacities. Quantitative genetics, therefore, provides an appropriate framework for the analysis of physiological phenotypes and can be used to infer the microevolutionary processes that have shaped patterns of trait variation within and among species. In cases where specific genes are known to contribute to variation in physiological traits, analyses of intraspecific polymorphism and interspecific divergence can reveal molecular mechanisms of functional evolution and can provide insights into the possible adaptive significance of observed sequence changes. In this review, we explain how the tools and theory of quantitative genetics, population genetics, and molecular evolution can inform our understanding of mechanism and process in physiological evolution. For example, lab-based studies of polygenic inheritance can be integrated with field-based studies of trait variation and survivorship to measure selection in the wild, thereby providing direct insights into the adaptive significance of physiological variation. Analyses of quantitative genetic variation in selection experiments can be used to probe interrelationships among traits and the genetic basis of physiological trade-offs and constraints. We review approaches for characterizing the genetic architecture of physiological traits, including linkage mapping and association mapping, and systems approaches for dissecting intermediary steps in the chain of causation between genotype and phenotype. We also discuss the promise and limitations of population genomic approaches for inferring adaptation at specific loci. We end by highlighting the role of organismal physiology in the functional synthesis of evolutionary biology. PMID:26041111

Morphological Characterization and Assessment of Genetic Variability, Character Association, and Divergence in Soybean Mutants

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M. A. Malek

2014-01-01

Full Text Available Genetic diversity is important for crop improvement. An experiment was conducted during 2011 to study genetic variability, character association, and genetic diversity among 27 soybean mutants and four mother genotypes. Analysis of variance revealed significant differences among the mutants and mothers for nine morphological traits. Eighteen mutants performed superiorly to their mothers in respect to seed yield and some morphological traits including yield attributes. Narrow differences between phenotypic and genotypic coefficients of variation (PCV and GCV for most of the characters revealed less environmental influence on their expression. High values of heritability and genetic advance with high GCV for branch number, plant height, pod number, and seed weight can be considered as favorable attributes for soybean improvement through phenotypic selection and high expected genetic gain can be achieved. Pod and seed number and maturity period appeared to be the first order traits for higher yield and priority should be given in selection due to their strong associations and high magnitudes of direct effects on yield. Cluster analysis grouped 31 genotypes into five groups at the coefficient value of 235. The mutants/genotypes from cluster I and cluster II could be used for hybridization program with the mutants of clusters IV and V in order to develop high yielding mutant-derived soybean varieties for further improvement.

Verification of consumers' experiences and perceptions of genetic discrimination and its impact on utilization of genetic testing.

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Barlow-Stewart, Kristine; Taylor, Sandra D; Treloar, Susan A; Stranger, Mark; Otlowski, Margaret

2009-03-01

To undertake a systematic process of verification of consumer accounts of alleged genetic discrimination. Verification of incidents reported in life insurance and other contexts that met the criteria of genetic discrimination, and the impact of fear of such treatment, was determined, with consent, through interview, document analysis and where appropriate, direct contact with the third party involved. The process comprised obtaining evidence that the alleged incident was accurately reported and determining whether the decision or action seemed to be justifiable and/or ethical. Reported incidents of genetic discrimination were verified in life insurance access, underwriting and coercion (9), applications for worker's compensation (1) and early release from prison (1) and in two cases of fear of discrimination impacting on access to genetic testing. Relevant conditions were inherited cancer susceptibility (8), Huntington disease (3), hereditary hemochromatosis (1), and polycystic kidney disease (1). In two cases, the reversal of an adverse underwriting decision to standard rate after intervention with insurers by genetics health professionals was verified. The mismatch between consumer and third party accounts in three life insurance incidents involved miscommunication or lack of information provision by financial advisers. These first cases of verified genetic discrimination make it essential for policies and guidelines to be developed and implemented to ensure appropriate use of genetic test results in insurance underwriting, to promote education and training in the financial industry, and to provide support for consumers and health professionals undertaking challenges of adverse decisions.

Causal Genetic Variation Underlying Metabolome Differences.

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Swain-Lenz, Devjanee; Nikolskiy, Igor; Cheng, Jiye; Sudarsanam, Priya; Nayler, Darcy; Staller, Max V; Cohen, Barak A

2017-08-01

An ongoing challenge in biology is to predict the phenotypes of individuals from their genotypes. Genetic variants that cause disease often change an individual's total metabolite profile, or metabolome. In light of our extensive knowledge of metabolic pathways, genetic variants that alter the metabolome may help predict novel phenotypes. To link genetic variants to changes in the metabolome, we studied natural variation in the yeast Saccharomyces cerevisiae We used an untargeted mass spectrometry method to identify dozens of metabolite Quantitative Trait Loci (mQTL), genomic regions containing genetic variation that control differences in metabolite levels between individuals. We mapped differences in urea cycle metabolites to genetic variation in specific genes known to regulate amino acid biosynthesis. Our functional assays reveal that genetic variation in two genes, AUA1 and ARG81 , cause the differences in the abundance of several urea cycle metabolites. Based on knowledge of the urea cycle, we predicted and then validated a new phenotype: sensitivity to a particular class of amino acid isomers. Our results are a proof-of-concept that untargeted mass spectrometry can reveal links between natural genetic variants and metabolome diversity. The interpretability of our results demonstrates the promise of using genetic variants underlying natural differences in the metabolome to predict novel phenotypes from genotype. Copyright © 2017 by the Genetics Society of America.

Molecular Epidemiology Reveals Genetic Diversity amongst Isolates of the Cryptococcus neoformans/C. gattii Species Complex in Thailand

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Kaocharoen, Sirada; Ngamskulrungroj, Popchai; Firacative, Carolina; Trilles, Luciana; Piyabongkarn, Dumrongdej; Banlunara, Wijit; Poonwan, Natteewan; Chaiprasert, Angkana; Meyer, Wieland; Chindamporn, Ariya

2013-01-01

To gain a more detailed picture of cryptococcosis in Thailand, a retrospective study of 498 C. neoformans and C. gattii isolates has been conducted. Among these, 386, 83 and 29 strains were from clinical, environmental and veterinary sources, respectively. A total of 485 C. neoformans and 13 C. gattii strains were studied. The majority of the strains (68.9%) were isolated from males (mean age of 37.97 years), 88.5% of C. neoformans and only 37.5% of C. gattii strains were from HIV patients. URA5-RFLP and/or M13 PCR-fingerprinting analysis revealed that the majority of the isolates were C. neoformans molecular type VNI regardless of their sources (94.8%; 94.6% of the clinical, 98.8% of the environmental and 86.2% of the veterinary isolates). In addition, the molecular types VNII (2.4%; 66.7% of the clinical and 33.3% of the veterinary isolates), VNIV (0.2%; 100% environmental isolate), VGI (0.2%; 100% clinical isolate) and VGII (2.4%; 100% clinical isolates) were found less frequently. Multilocus Sequence Type (MLST) analysis using the ISHAM consensus MLST scheme for the C. neoformans/C. gattii species complex identified a total of 20 sequence types (ST) in Thailand combining current and previous data. The Thai isolates are an integrated part of the global cryptococcal population genetic structure, with ST30 for C. gattii and ST82, ST83, ST137, ST141, ST172 and ST173 for C. neoformans being unique to Thailand. Most of the C. gattii isolates were ST7 = VGIIb, which is identical to the less virulent minor Vancouver island outbreak genotype, indicating Thailand as a stepping stone in the global spread of this outbreak strain. The current study revealed a greater genetic diversity and a wider range of major molecular types being present amongst Thai cryptococcal isolates than previously reported. PMID:23861989

Genetic effects of PDGFRB and MARCH1 identified in GWAS revealing strong associations with semen production traits in Chinese Holstein bulls.

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Liu, Shuli; Yin, Hongwei; Li, Cong; Qin, Chunhua; Cai, Wentao; Cao, Mingyue; Zhang, Shengli

2017-07-03

Using a genome-wide association study strategy, our previous study discovered 19 significant single-nucleotide polymorphisms (SNPs) related to semen production traits in Chinese Holstein bulls. Among them, three SNPs were within or close to the phosphodiesterase 3A (PDE3A), membrane associated ring-CH-type finger 1 (MARCH1) and platelet derived growth factor receptor beta (PDGFRB) genes. The present study was designed with the objectives of identifying genetic polymorphism of the PDE3A, PDGFRB and MARCH1 genes and their effects on semen production traits in a Holstein bull population. A total of 20 SNPs were detected and genotyped in 730 bulls. Association analyses using de-regressed estimated breeding values of each semen production trait revealed four statistically significant SNPs for one or more semen production traits (P semen volume per ejaculate. Furthermore, high expression of the MARCH1 gene was observed in sperm cells. One SNP (rs43445726) in the regulatory region of MARCH1 had a significant effect on gene expression. Our study demonstrated the significant associations of genetic variants of the PDGFRB and MARCH1 genes with semen production traits. The identified SNPs may serve as genetic markers to optimize breeding programs for semen production traits in Holstein bull populations.

Expression quantitative trait loci and genetic regulatory network analysis reveals that Gabra2 is involved in stress responses in the mouse.

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Dai, Jiajuan; Wang, Xusheng; Chen, Ying; Wang, Xiaodong; Zhu, Jun; Lu, Lu

2009-11-01

Previous studies have revealed that the subunit alpha 2 (Gabra2) of the gamma-aminobutyric acid receptor plays a critical role in the stress response. However, little is known about the gentetic regulatory network for Gabra2 and the stress response. We combined gene expression microarray analysis and quantitative trait loci (QTL) mapping to characterize the genetic regulatory network for Gabra2 expression in the hippocampus of BXD recombinant inbred (RI) mice. Our analysis found that the expression level of Gabra2 exhibited much variation in the hippocampus across the BXD RI strains and between the parental strains, C57BL/6J, and DBA/2J. Expression QTL (eQTL) mapping showed three microarray probe sets of Gabra2 to have highly significant linkage likelihood ratio statistic (LRS) scores. Gene co-regulatory network analysis showed that 10 genes, including Gria3, Chka, Drd3, Homer1, Grik2, Odz4, Prkag2, Grm5, Gabrb1, and Nlgn1 are directly or indirectly associated with stress responses. Eleven genes were implicated as Gabra2 downstream genes through mapping joint modulation. The genetical genomics approach demonstrates the importance and the potential power of the eQTL studies in identifying genetic regulatory networks that contribute to complex traits, such as stress responses.

Are genetic risk factors for psychosis also associated with dimension-specific psychotic experiences in adolescence?

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Dominika Sieradzka

Full Text Available Psychosis has been hypothesised to be a continuously distributed quantitative phenotype and disorders such as schizophrenia and bipolar disorder represent its extreme manifestations. Evidence suggests that common genetic variants play an important role in liability to both schizophrenia and bipolar disorder. Here we tested the hypothesis that these common variants would also influence psychotic experiences measured dimensionally in adolescents in the general population. Our aim was to test whether schizophrenia and bipolar disorder polygenic risk scores (PRS, as well as specific single nucleotide polymorphisms (SNPs previously identified as risk variants for schizophrenia, were associated with adolescent dimension-specific psychotic experiences. Self-reported Paranoia, Hallucinations, Cognitive Disorganisation, Grandiosity, Anhedonia, and Parent-rated Negative Symptoms, as measured by the Specific Psychotic Experiences Questionnaire (SPEQ, were assessed in a community sample of 2,152 16-year-olds. Polygenic risk scores were calculated using estimates of the log of odds ratios from the Psychiatric Genomics Consortium GWAS stage-1 mega-analysis of schizophrenia and bipolar disorder. The polygenic risk analyses yielded no significant associations between schizophrenia and bipolar disorder PRS and the SPEQ measures. The analyses on the 28 individual SNPs previously associated with schizophrenia found that two SNPs in TCF4 returned a significant association with the SPEQ Paranoia dimension, rs17512836 (p-value = 2.57×10⁻⁴ and rs9960767 (p-value = 6.23×10⁻⁴. Replication in an independent sample of 16-year-olds (N = 3,427 assessed using the Psychotic-Like Symptoms Questionnaire (PLIKS-Q, a composite measure of multiple positive psychotic experiences, failed to yield significant results. Future research with PRS derived from larger samples, as well as larger adolescent validation samples, would improve the predictive power to test

Genetic diversity and relationships among different tomato varieties revealed by EST-SSR markers.

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Korir, N K; Diao, W; Tao, R; Li, X; Kayesh, E; Li, A; Zhen, W; Wang, S

2014-01-08

The genetic diversity and relationship of 42 tomato varieties sourced from different geographic regions was examined with EST-SSR markers. The genetic diversity was between 0.18 and 0.77, with a mean of 0.49; the polymorphic information content ranged from 0.17 to 0.74, with a mean of 0.45. This indicates a fairly high degree of diversity among these tomato varieties. Based on the cluster analysis using unweighted pair-group method with arithmetic average (UPGMA), all the tomato varieties fell into 5 groups, with no obvious geographical distribution characteristics despite their diverse sources. The principal component analysis (PCA) supported the clustering result; however, relationships among varieties were more complex in the PCA scatterplot than in the UPGMA dendrogram. This information about the genetic relationships between these tomato lines helps distinguish these 42 varieties and will be useful for tomato variety breeding and selection. We confirm that the EST-SSR marker system is useful for studying genetic diversity among tomato varieties. The high degree of polymorphism and the large number of bands obtained per assay shows that SSR is the most informative marker system for tomato genotyping for purposes of rights/protection and for the tomato industry in general. It is recommended that these varieties be subjected to identification using an SSR-based manual cultivar identification diagram strategy or other easy-to-use and referable methods so as to provide a complete set of information concerning genetic relationships and a readily usable means of identifying these varieties.

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics. RANA GOPAL SINGH. Articles written in Journal of Genetics. Volume 96 Issue 6 December 2017 pp 885-893 RESEARCH ARTICLE. Mutational screening of PKD2 gene in the north Indian polycystic kidney disease patients revealed 28 genetic variations · SONAM RAJ RANA GOPAL ...

Genetic diversity of Bemisia tabaci (Genn. Populations in Brazil revealed by RAPD markers

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L.H.C. Lima

2002-01-01

Full Text Available Bemisia tabaci (Genn. was considered a secondary pest in Brazil until 1990, despite being an efficient geminivirus vector in beans and soybean. In 1991, a new biotype, known as B. tabaci B biotype (=B. argentifolii was detected attacking weed plants and causing phytotoxic problems in Cucurbitaceae. Nowadays, B. tabaci is considered one of the most damaging whitefly pests in agricultural systems worldwide that transmits more than 60 different plant viruses. Little is known about the genetic variability of these populations in Brazil. Knowledge of the genetic variation within whitefly populations is necessary for their efficient control and management. The objectives of the present study were to use RAPD markers (1 to estimate the genetic diversity of B. tabaci populations, (2 to study the genetic relationships among B. tabaci biotypes and two other whitefly species and (3 to discriminate between B. tabaci biotypes. A sample of 109 B. tabaci female individuals obtained from 12 populations in Brazil were analyzed and compared to the A biotype from Arizona (USA and B biotype from California (USA and Paraguay. Trialeurodes vaporariorum and Aleurodicus cocois samples were also included. A total of 72 markers were generated by five RAPD primers and used in the analysis. All primers produced RAPD patterns that clearly distinguished the Bemisia biotypes and the two other whitefly species. Results also showed that populations of the B biotype have considerable genetic variability. An average Jaccard similarity of 0.73 was observed among the B biotype individuals analyzed. Cluster analysis demonstrated that, in general, Brazilian biotype B individuals are scattered independently in the localities where samples were collected. Nevertheless, some clusters were evident, joining individuals according to the host plants. AMOVA showed that most of the total genetic variation is found within populations (56.70%, but a significant portion of the variation is found

A genetic diagnosis of maturity-onset diabetes of the young (MODY): experiences of patients and family members.

Science.gov (United States)

Bosma, A R; Rigter, T; Weinreich, S S; Cornel, M C; Henneman, L

2015-10-01

Genetic testing for maturity-onset diabetes of the young (MODY) facilitates a correct diagnosis, enabling treatment optimization and allowing monitoring of asymptomatic family members. To date, the majority of people with MODY remain undiagnosed. To identify patients' needs and areas for improving care, this study explores the experiences of patients and family members who have been genetically tested for MODY. Fourteen semi-structured interviews with patients and the parents of patients, and symptomatic and asymptomatic family members were conducted. Atlas.ti was used for thematic analysis. Most people with MODY were initially misdiagnosed with Type 1 or Type 2 diabetes; they had been seeking for the correct diagnosis for a long time. Reasons for having a genetic test included reassurance, removing the uncertainty of developing diabetes (in asymptomatic family members) and informing relatives. Reasons against testing were the fear of genetic discrimination and not having symptoms. Often a positive genetic test result did not come as a surprise. Both patients and family members were satisfied with the decision to get tested because it enabled them to adjust their lifestyle and treatment accordingly. All participants experienced a lack of knowledge of MODY among healthcare professionals, in their social environment and in patient organizations. Additionally, problems with the reimbursement of medical expenses were reported. Patients and family members are generally positive about genetic testing for MODY. More education of healthcare professionals and attention on the part of diabetes organizations is needed to increase awareness and optimize care and support for people with MODY. © 2015 The Authors. Diabetic Medicine © 2015 Diabetes UK.

Population structure and genetic diversity of Indian Major Carp, Labeo rohita (Hamilton, 1822) from three phylo-geographically isolated riverine ecosystems of India as revealed by mtDNA cytochrome b region sequences.

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Behera, Bijay Kumar; Baisvar, Vishwamitra Singh; Kunal, Swaraj Priyaranjan; Meena, Dharmendra Kumar; Panda, Debarata; Pakrashi, Sudip; Paria, Prasenjit; Das, Pronob; Bhakta, Dibakar; Debnath, Dipesh; Roy, Suvra; Suresh, V R; Jena, J K

2018-03-01

The population structure and genetic diversity of Rohu (Labeo rohita Hamilton, 1822) was studied by analysis of the partial sequences of mitochondrial DNA cytochrome b region. We examined 133 samples collected from six locations in three geographically isolated rivers of India. Analysis of 11 haplotypes showed low haplotype diversity (0.00150), nucleotide diversity (π) (0.02884) and low heterogeneity value (0.00374). Analysis of molecular variance (AMOVA) revealed the genetic diversity of L. rohita within population is very high than between the populations. The Fst scores (-0.07479 to 0.07022) were the indication of low genetic structure of L. rohita populations of three rivers of India. Conspicuously, Farakka-Bharuch population pair Fst score of 0.0000, although the sampling sites are from different rivers. The phylogenetic reconstruction of unique haplotypes revealed sharing of a single central haplotype (Hap_1) by all the six populations with a point mutations ranging from 1-25 nucleotides.

Genetic Counselors' Experiences Regarding Communication of Reproductive Risks with Autosomal Recessive Conditions found on Cancer Panels.

Science.gov (United States)

Mets, Sarah; Tryon, Rebecca; Veach, Patricia McCarthy; Zierhut, Heather A

2016-04-01

The development of hereditary cancer genetic testing panels has altered genetic counseling practice. Mutations within certain genes on cancer panels pose not only a cancer risk, but also a reproductive risk for autosomal recessive conditions such as Fanconi anemia, constitutional mismatch repair deficiency syndrome, and ataxia telangiectasia. This study aimed to determine if genetic counselors discuss reproductive risks for autosomal recessive conditions associated with genes included on cancer panels, and if so, under what circumstances these risks are discussed. An on-line survey was emailed through the NSGC list-serv. The survey assessed 189 cancer genetic counselors' experiences discussing reproductive risks with patients at risk to carry a mutation or variant of uncertain significance (VUS) in a gene associated with both an autosomal dominant cancer risk and an autosomal recessive syndrome. Over half (n = 82, 55 %) reported having discussed reproductive risks; the remainder (n = 66, 45 %) had not. Genetic counselors who reported discussing reproductive risks primarily did so when patients had a positive result and were of reproductive age. Reasons for not discussing these risks included when a patient had completed childbearing or when a VUS was identified. Most counselors discussed reproductive risk after obtaining results and not during the informed consent process. There is inconsistency as to if and when the discussion of reproductive risks is taking place. The wide variation in responses suggests a need to develop professional guidelines for when and how discussions of reproductive risk for autosomal recessive conditions identified through cancer panels should occur with patients.

Genetic Diversity in Commercial Rapeseed (Brassica napus L. Varieties from Turkey as Revealed by RAPD

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Özlem ÖZBEK

2013-02-01

Full Text Available In cultivated commercial crop species, genetic diversity tends to decrease because of the extensive breeding processes. Therefore, germplasm of commercial crop species, such as Brassica napus L. should be evaluated and the genotypes, which have higher genetic diversity index, should be addressed as potential parental cross materials in breeding programs. In this study, the genetic diversity was analysed by using randomly amplified polymorphic DNA analysis (RAPD technique in nine Turkish commercial rapeseed varieties. The RAPD primers (10-mer oligonucleotides produced 51 scorable loci, 31 loci of which were polymorphic (60.78% and 20 loci (39.22% were monomorphic The RAPD bands were scored as binary matrix data and were analysed using POPGENE version 1.32. At locus level, the values of genetic diversity within population (Hs and total (HT were 0.15 and 0.19 respectively. The genetic differentiation (GST and the gene flow (Nm values between the populations were 0.20 and 2.05 respectively. The mean number of alleles (na, the mean number of effective alleles (nae, and the mean value of genetic diversity (He were 2.00, 1.26, and 0.19 respectively. According to Pearson’s correlation, multiple regression and principal component analyses, eco-geographical conditions in combination had significant effect on genetic indices of commercial B. napus L. varieties were discussed.

[Genetic information and future medicine].

Science.gov (United States)

Sakurai, Akihiro

2012-11-01

Rapid technological advances in genetic analysis have revealed the genetic background of various diseases. Elucidation of the genes responsible for a disease enables better clinical management of the disease and helps to develop targeted drugs. Also, early diagnosis and management of at-risk family members can be made by identification of a genetic disease in the proband. On the other hand, genetic issues often cause psychological distress to the family. To perform genetic testing appropriately and to protect patients and family members from any harm, guidelines for genetic testing were released from the alliance of Japanese genetics-related academic societies in 2003. As genetic testing is becoming incorporated into clinical practice more broadly, the guideline was revised and released by the Japanese Society of Medical Sciences in 2011. All medical professionals in Japan are expected to follow this guideline.

Psychiatric genetic testing: Attitudes and intentions among future users and providers

DEFF Research Database (Denmark)

Laegsgaard, Mett Marri; Mors, Ole

2008-01-01

as a guide in this field, but the optimal utilization of genetic testing has also been recognized to depend on knowledge of the potential consumers' attitudes. To provide knowledge to inform the public debate on mental illness and genetics, and the future conducting of psychiatric genetic testing....... Psychiatric and somatic genetic testing attracted the same amounts of accept. General attitudes toward access to psychiatric genetic testing and information revealed substantial support for bioethical principles of autonomy and privacy. However, questions describing more specific situations revealed......Psychiatric genetic research may eventually render possible psychiatric genetic testing. Whereas all genetic knowledge has certain characteristics raising ethical, legal, and social issues, psychiatric genetic knowledge adds more controversial issues. Ethical principles have been proposed...

Early Life Experiences and Exercise Associate with Canine Anxieties.

Science.gov (United States)

Tiira, Katriina; Lohi, Hannes

2015-01-01

Personality and anxiety disorders across species are affected by genetic and environmental factors. Shyness-boldness personality continuum exists across species, including the domestic dog, with a large within- and across-breed variation. Domestic dogs are also diagnosed for several anxiety-related behavioral conditions, such as generalized anxiety disorders, phobias, and separation anxiety. Genetic and environmental factors contributing to personality and anxiety are largely unknown. We collected questionnaire data from a Finnish family dog population (N = 3264) in order to study the associating environmental factors for canine fearfulness, noise sensitivity, and separation anxiety. Early life experiences and exercise were found to associate with anxiety prevalence. We found that fearful dogs had less socialization experiences (p = 0.002) and lower quality of maternal care (p daily exercise; dogs with noise sensitivity and separation anxiety had less daily exercise. Our findings suggest that dogs share many of the same environmental factors that contribute to anxiety in other species as well, such as humans and rodents. Our study highlights the importance of early life experiences, especially the quality of maternal care and daily exercise for the welfare and management of the dogs, and reveals important confounding factors to be considered in the genetic characterization of canine anxiety.

Genetic diversity and domestication origin of tea plant Camellia taliensis (Theaceae) as revealed by microsatellite markers.

Science.gov (United States)

Zhao, Dong-Wei; Yang, Jun-Bo; Yang, Shi-Xiong; Kato, Kenji; Luo, Jian-Ping

2014-01-09

Tea is one of the most popular beverages in the world. Many species in the Thea section of the Camellia genus can be processed for drinking and have been domesticated. However, few investigations have focused on the genetic consequence of domestication and geographic origin of landraces on tea plants using credible wild and planted populations of a single species. Here, C. taliensis provides us with a unique opportunity to explore these issues. Fourteen nuclear microsatellite loci were employed to determine the genetic diversity and domestication origin of C. taliensis, which were represented by 587 individuals from 25 wild, planted and recently domesticated populations. C. taliensis showed a moderate high level of overall genetic diversity. The greater reduction of genetic diversity and stronger genetic drift were detected in the wild group than in the recently domesticated group, indicating the loss of genetic diversity of wild populations due to overexploitation and habitat fragmentation. Instead of the endangered wild trees, recently domesticated individuals were used to compare with the planted trees for detecting the genetic consequence of domestication. A little and non-significant reduction in genetic diversity was found during domestication. The long life cycle, selection for leaf traits and gene flow between populations will delay the emergence of bottleneck in planted trees. Both phylogenetic and assignment analyses suggested that planted trees may have been domesticated from the adjacent central forest of western Yunnan and dispersed artificially to distant places. This study contributes to the knowledge about levels and distribution of genetic diversity of C. taliensis and provides new insights into genetic consequence of domestication and geographic origin of planted trees of this species. As an endemic tea source plant, wild, planted and recently domesticated C. taliensis trees should all be protected for their unique genetic characteristics, which

Mitochondrial DNA Variation Reveals a Sharp Genetic Break within the Distribution of the Blue Land Crab Cardisoma guanhumi in the Western Central Atlantic

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Maria Rosimere Xavier Amaral

2015-08-01

Full Text Available The blue land crab Cardisoma guanhumi is widely distributed throughout tropical and subtropical estuarine regions in the Western Central Atlantic (WCA. Patterns of population genetic structure and historical demographics of the species were assessed by mtDNA control region sequence analysis to examine the connectivity among five populations (n = 97 within the region for future conservation strategies and decision-making of fishery management. A total of 234 polymorphic nucleotides were revealed within the sequence region, which have defined 93 distinct haplotypes. No dominant mtDNA haplotypes were found but instead a distribution of a few low-frequency recurrent haplotypes with a large number of singletons. A NJ-tree and a median-joining haplotype network revealed two distinct clusters, corresponding to individuals from estuaries located along the Caribbean Sea and Brazilian waters, respectively. AMOVA and FST statistics supported the hypothesis that two main geographic regions exists. Phylogeographical discontinuity was further demonstrated by the Bayesian assignment analysis and a significant pattern of isolation-by-distance. Additionally, tests of neutral evolution and analysis of mismatch distribution indicate a complex demographic history in the WCA, which corresponds to bottleneck and subsequent population growth. Overall, a sharp genetic break between Caribbean and Brazilian populations raised concerns over the conservation status of the blue land crab.

HSP90 Shapes the Consequences of Human Genetic Variation.

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Karras, Georgios I; Yi, Song; Sahni, Nidhi; Fischer, Máté; Xie, Jenny; Vidal, Marc; D'Andrea, Alan D; Whitesell, Luke; Lindquist, Susan

2017-02-23

HSP90 acts as a protein-folding buffer that shapes the manifestations of genetic variation in model organisms. Whether HSP90 influences the consequences of mutations in humans, potentially modifying the clinical course of genetic diseases, remains unknown. By mining data for >1,500 disease-causing mutants, we found a strong correlation between reduced phenotypic severity and a dominant (HSP90 ≥ HSP70) increase in mutant engagement by HSP90. Examining the cancer predisposition syndrome Fanconi anemia in depth revealed that mutant FANCA proteins engaged predominantly by HSP70 had severely compromised function. In contrast, the function of less severe mutants was preserved by a dominant increase in HSP90 binding. Reducing HSP90's buffering capacity with inhibitors or febrile temperatures destabilized HSP90-buffered mutants, exacerbating FA-related chemosensitivities. Strikingly, a compensatory FANCA somatic mutation from an "experiment of nature" in monozygotic twins both prevented anemia and reduced HSP90 binding. These findings provide one plausible mechanism for the variable expressivity and environmental sensitivity of genetic diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Desktop Genetics

OpenAIRE

Hough, Soren H; Ajetunmobi, Ayokunmi; Brody, Leigh; Humphryes-Kirilov, Neil; Perello, Edward

2016-01-01

Desktop Genetics is a bioinformatics company building a gene-editing platform for personalized medicine. The company works with scientists around the world to design and execute state-of-the-art clustered regularly interspaced short palindromic repeats (CRISPR) experiments. Desktop Genetics feeds the lessons learned about experimental intent, single-guide RNA design and data from international genomics projects into a novel CRISPR artificial intelligence system. We believe that machine learni...

Non-invasive genetics outperforms morphological methods in faecal dietary analysis, revealing wild boar as a considerable conservation concern for ground-nesting birds.

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Oja, Ragne; Soe, Egle; Valdmann, Harri; Saarma, Urmas

2017-01-01

Capercaillie (Tetrao urogallus) and other grouse species represent conservation concerns across Europe due to their negative abundance trends. In addition to habitat deterioration, predation is considered a major factor contributing to population declines. While the role of generalist predators on grouse predation is relatively well known, the impact of the omnivorous wild boar has remained elusive. We hypothesize that wild boar is an important predator of ground-nesting birds, but has been neglected as a bird predator because traditional morphological methods underestimate the proportion of birds in wild boar diet. To distinguish between different mammalian predator species, as well as different grouse prey species, we developed a molecular method based on the analysis of mitochondrial DNA that allows accurate species identification. We collected 109 wild boar faeces at protected capercaillie leks and surrounding areas and analysed bird consumption using genetic methods and classical morphological examination. Genetic analysis revealed that the proportion of birds in wild boar faeces was significantly higher (17.3%; 4.5×) than indicated by morphological examination (3.8%). Moreover, the genetic method allowed considerably more precise taxonomic identification of consumed birds compared to morphological analysis. Our results demonstrate: (i) the value of using genetic approaches in faecal dietary analysis due to their higher sensitivity, and (ii) that wild boar is an important predator of ground-nesting birds, deserving serious consideration in conservation planning for capercaillie and other grouse.

Eliciting preferences for priority setting in genetic testing: a pilot study comparing best-worst scaling and discrete-choice experiments

OpenAIRE

Severin, Franziska; Schmidtke, Jörg; Mühlbacher, Axel; Rogowski, Wolf H

2013-01-01

Given the increasing number of genetic tests available, decisions have to be made on how to allocate limited health-care resources to them. Different criteria have been proposed to guide priority setting. However, their relative importance is unclear. Discrete-choice experiments (DCEs) and best-worst scaling experiments (BWSs) are methods used to identify and weight various criteria that influence orders of priority. This study tests whether these preference eliciting techniques can be used f...

Revealing life-history traits by contrasting genetic estimations with predictions of effective population size.

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Greenbaum, Gili; Renan, Sharon; Templeton, Alan R; Bouskila, Amos; Saltz, David; Rubenstein, Daniel I; Bar-David, Shirli

2017-12-22

Effective population size, a central concept in conservation biology, is now routinely estimated from genetic surveys and can also be theoretically predicted from demographic, life-history, and mating-system data. By evaluating the consistency of theoretical predictions with empirically estimated effective size, insights can be gained regarding life-history characteristics and the relative impact of different life-history traits on genetic drift. These insights can be used to design and inform management strategies aimed at increasing effective population size. We demonstrated this approach by addressing the conservation of a reintroduced population of Asiatic wild ass (Equus hemionus). We estimated the variance effective size (N ev ) from genetic data (N ev =24.3) and formulated predictions for the impacts on N ev of demography, polygyny, female variance in lifetime reproductive success (RS), and heritability of female RS. By contrasting the genetic estimation with theoretical predictions, we found that polygyny was the strongest factor affecting genetic drift because only when accounting for polygyny were predictions consistent with the genetically measured N ev . The comparison of effective-size estimation and predictions indicated that 10.6% of the males mated per generation when heritability of female RS was unaccounted for (polygyny responsible for 81% decrease in N ev ) and 19.5% mated when female RS was accounted for (polygyny responsible for 67% decrease in N ev ). Heritability of female RS also affected N ev ; hf2=0.91 (heritability responsible for 41% decrease in N ev ). The low effective size is of concern, and we suggest that management actions focus on factors identified as strongly affecting Nev, namely, increasing the availability of artificial water sources to increase number of dominant males contributing to the gene pool. This approach, evaluating life-history hypotheses in light of their impact on effective population size, and contrasting

Genetic Diversity in Commercial Rapeseed (Brassica napus L.) Varieties from Turkey as Revealed by RAPD

OpenAIRE

Özlem ÖZBEK; Betül Uçar GIDIK

2013-01-01

In cultivated commercial crop species, genetic diversity tends to decrease because of the extensive breeding processes. Therefore, germplasm of commercial crop species, such as Brassica napus L. should be evaluated and the genotypes, which have higher genetic diversity index, should be addressed as potential parental cross materials in breeding programs. In this study, the genetic diversity was analysed by using randomly amplified polymorphic DNA analysis (RAPD) technique in nine Turkish com...

Multiple genetic interaction experiments provide complementary information useful for gene function prediction.

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Magali Michaut

Full Text Available Genetic interactions help map biological processes and their functional relationships. A genetic interaction is defined as a deviation from the expected phenotype when combining multiple genetic mutations. In Saccharomyces cerevisiae, most genetic interactions are measured under a single phenotype - growth rate in standard laboratory conditions. Recently genetic interactions have been collected under different phenotypic readouts and experimental conditions. How different are these networks and what can we learn from their differences? We conducted a systematic analysis of quantitative genetic interaction networks in yeast performed under different experimental conditions. We find that networks obtained using different phenotypic readouts, in different conditions and from different laboratories overlap less than expected and provide significant unique information. To exploit this information, we develop a novel method to combine individual genetic interaction data sets and show that the resulting network improves gene function prediction performance, demonstrating that individual networks provide complementary information. Our results support the notion that using diverse phenotypic readouts and experimental conditions will substantially increase the amount of gene function information produced by genetic interaction screens.

Genetics of aggression.

Science.gov (United States)

Anholt, Robert R H; Mackay, Trudy F C

2012-01-01

Aggression mediates competition for food, mating partners, and habitats and, among social animals, establishes stable dominance hierarchies. In humans, abnormal aggression is a hallmark of neuropsychiatric disorders and can be elicited by environmental factors acting on an underlying genetic susceptibility. Identifying the genetic architecture that predisposes to aggressive behavior in people is challenging because of difficulties in quantifying the phenotype, genetic heterogeneity, and uncontrolled environmental conditions. Studies on mice have identified single-gene mutations that result in hyperaggression, contingent on genetic background. These studies can be complemented by systems genetics approaches in Drosophila melanogaster, in which mutational analyses together with genome-wide transcript analyses, artificial selection studies, and genome-wide analysis of epistasis have revealed that a large segment of the genome contributes to the manifestation of aggressive behavior with widespread epistatic interactions. Comparative genomic analyses based on the principle of evolutionary conservation are needed to enable a complete dissection of the neurogenetic underpinnings of this universal fitness trait.

What do men understand about lifetime risk following genetic testing? The effect of context and numeracy.

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Rolison, Jonathan J; Hanoch, Yaniv; Miron-Shatz, Talya

2012-07-01

Genetic testing for gene mutations associated with specific cancers provides an opportunity for early detection, surveillance, and intervention (Smith, Cokkinides, & Brawley, 2008). Lifetime risk estimates provided by genetic testing refer to the risk of developing a specific disease within one's lifetime, and evidence suggests that this is important for the medical choices people make, as well as their future family and financial plans. The present studies tested whether adult men understand the lifetime risks of prostate cancer informed by genetic testing. In 2 experiments, adult men were asked to interpret the lifetime risk information provided in statements about risks of prostate cancer. Statement format was manipulated such that the most appropriate interpretation of risk statements referred to an absolute risk of cancer in experiment 1 and a relative risk in experiment 2. Experiment 1 revealed that few men correctly interpreted the lifetime risks of cancer when these refer to an absolute risk of cancer, and numeracy levels positively predicted correct responding. The proportion of correct responses was greatly improved in experiment 2 when the most appropriate interpretation of risk statements referred instead to a relative rather than an absolute risk, and numeracy levels were less involved. Understanding of lifetime risk information is often poor because individuals incorrectly believe that these refer to relative rather than absolute risks of cancer.

Genetic Mapping in Mice Reveals the Involvement of Pcdh9 in Long-Term Social and Object Recognition and Sensorimotor Development.

Science.gov (United States)

Bruining, Hilgo; Matsui, Asuka; Oguro-Ando, Asami; Kahn, René S; Van't Spijker, Heleen M; Akkermans, Guus; Stiedl, Oliver; van Engeland, Herman; Koopmans, Bastijn; van Lith, Hein A; Oppelaar, Hugo; Tieland, Liselotte; Nonkes, Lourens J; Yagi, Takeshi; Kaneko, Ryosuke; Burbach, J Peter H; Yamamoto, Nobuhiko; Kas, Martien J

2015-10-01

Quantitative genetic analysis of basic mouse behaviors is a powerful tool to identify novel genetic phenotypes contributing to neurobehavioral disorders. Here, we analyzed genetic contributions to single-trial, long-term social and nonsocial recognition and subsequently studied the functional impact of an identified candidate gene on behavioral development. Genetic mapping of single-trial social recognition was performed in chromosome substitution strains, a sophisticated tool for detecting quantitative trait loci (QTL) of complex traits. Follow-up occurred by generating and testing knockout (KO) mice of a selected QTL candidate gene. Functional characterization of these mice was performed through behavioral and neurological assessments across developmental stages and analyses of gene expression and brain morphology. Chromosome substitution strain 14 mapping studies revealed an overlapping QTL related to long-term social and object recognition harboring Pcdh9, a cell-adhesion gene previously associated with autism spectrum disorder. Specific long-term social and object recognition deficits were confirmed in homozygous (KO) Pcdh9-deficient mice, while heterozygous mice only showed long-term social recognition impairment. The recognition deficits in KO mice were not associated with alterations in perception, multi-trial discrimination learning, sociability, behavioral flexibility, or fear memory. Rather, KO mice showed additional impairments in sensorimotor development reflected by early touch-evoked biting, rotarod performance, and sensory gating deficits. This profile emerged with structural changes in deep layers of sensory cortices, where Pcdh9 is selectively expressed. This behavior-to-gene study implicates Pcdh9 in cognitive functions required for long-term social and nonsocial recognition. This role is supported by the involvement of Pcdh9 in sensory cortex development and sensorimotor phenotypes. Copyright © 2015 Society of Biological Psychiatry. Published

A Next-Generation Sequencing Data Analysis Pipeline for Detecting Unknown Pathogens from Mixed Clinical Samples and Revealing Their Genetic Diversity.

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Yu-Nong Gong

Full Text Available Forty-two cytopathic effect (CPE-positive isolates were collected from 2008 to 2012. All isolates could not be identified for known viral pathogens by routine diagnostic assays. They were pooled into 8 groups of 5-6 isolates to reduce the sequencing cost. Next-generation sequencing (NGS was conducted for each group of mixed samples, and the proposed data analysis pipeline was used to identify viral pathogens in these mixed samples. Polymerase chain reaction (PCR or enzyme-linked immunosorbent assay (ELISA was individually conducted for each of these 42 isolates depending on the predicted viral types in each group. Two isolates remained unknown after these tests. Moreover, iteration mapping was implemented for each of these 2 isolates, and predicted human parechovirus (HPeV in both. In summary, our NGS pipeline detected the following viruses among the 42 isolates: 29 human rhinoviruses (HRVs, 10 HPeVs, 1 human adenovirus (HAdV, 1 echovirus and 1 rotavirus. We then focused on the 10 identified Taiwanese HPeVs because of their reported clinical significance over HRVs. Their genomes were assembled and their genetic diversity was explored. One novel 6-bp deletion was found in one HPeV-1 virus. In terms of nucleotide heterogeneity, 64 genetic variants were detected from these HPeVs using the mapped NGS reads. Most importantly, a recombination event was found between our HPeV-3 and a known HPeV-4 strain in the database. Similar event was detected in the other HPeV-3 strains in the same clade of the phylogenetic tree. These findings demonstrated that the proposed NGS data analysis pipeline identified unknown viruses from the mixed clinical samples, revealed their genetic identity and variants, and characterized their genetic features in terms of viral evolution.

Population genetic analysis of Colombian Trypanosoma cruzi isolates revealed by enzyme electrophoretic profiles

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Manuel Ruiz-Garcia

2001-01-01

Full Text Available Although Colombia presents an enormous biological diversity, few studies have been conducted on the population genetics of Trypanosoma cruzi. This study was carried out with 23 Colombian stocks of this protozoa analyzed for 13 isoenzymatic loci. The Hardy-Weinberg equilibrium, the genetic diversity and heterogeneity, the genetic relationships and the possible spatial structure of these 23 Colombian stocks of T. cruzi were estimated. The majority of results obtained are in agreement with a clonal population structure. Nevertheless, two aspects expected in a clonal structure were not discovered in the Colombian T. cruzi stocks. There was an absence of given zymodemes over-represented from a geographical point of view and the presumed temporal stabilizing selective phenomena was not observed either in the Colombian stocks sampled several times through the years of the study. Some hypotheses are discussed in order to explain the results found.

Genetic and genomic diversity studies of Acacia symbionts in Senegal reveal new species of Mesorhizobium with a putative geographical pattern.

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Diouf, Fatou; Diouf, Diegane; Klonowska, Agnieszka; Le Queré, Antoine; Bakhoum, Niokhor; Fall, Dioumacor; Neyra, Marc; Parrinello, Hugues; Diouf, Mayecor; Ndoye, Ibrahima; Moulin, Lionel

2015-01-01

Acacia senegal (L) Willd. and Acacia seyal Del. are highly nitrogen-fixing and moderately salt tolerant species. In this study we focused on the genetic and genomic diversity of Acacia mesorhizobia symbionts from diverse origins in Senegal and investigated possible correlations between the genetic diversity of the strains, their soil of origin, and their tolerance to salinity. We first performed a multi-locus sequence analysis on five markers gene fragments on a collection of 47 mesorhizobia strains of A. senegal and A. seyal from 8 localities. Most of the strains (60%) clustered with the M. plurifarium type strain ORS 1032T, while the others form four new clades (MSP1 to MSP4). We sequenced and assembled seven draft genomes: four in the M. plurifarium clade (ORS3356, ORS3365, STM8773 and ORS1032T), one in MSP1 (STM8789), MSP2 (ORS3359) and MSP3 (ORS3324). The average nucleotide identities between these genomes together with the MLSA analysis reveal three new species of Mesorhizobium. A great variability of salt tolerance was found among the strains with a lack of correlation between the genetic diversity of mesorhizobia, their salt tolerance and the soils samples characteristics. A putative geographical pattern of A. senegal symbionts between the dryland north part and the center of Senegal was found, reflecting adaptations to specific local conditions such as the water regime. However, the presence of salt does not seem to be an important structuring factor of Mesorhizobium species.

New Genetics

Science.gov (United States)

... of the booklet. » more Chapter 1: How Genes Work Covers DNA, RNA, transcription, RNA splicing, translation, ribosomes, antibiotics, genetic diseases, gene chips. » more Chapter 2: RNA and DNA Revealed: New Roles, New Rules Covers microRNAs, RNAi, epigenetics, telomeres, mtDNA, recombinant DNA. » ...

Genetic Algorithms for Multiple-Choice Problems

Science.gov (United States)

Aickelin, Uwe

2010-04-01

This thesis investigates the use of problem-specific knowledge to enhance a genetic algorithm approach to multiple-choice optimisation problems.It shows that such information can significantly enhance performance, but that the choice of information and the way it is included are important factors for success.Two multiple-choice problems are considered.The first is constructing a feasible nurse roster that considers as many requests as possible.In the second problem, shops are allocated to locations in a mall subject to constraints and maximising the overall income.Genetic algorithms are chosen for their well-known robustness and ability to solve large and complex discrete optimisation problems.However, a survey of the literature reveals room for further research into generic ways to include constraints into a genetic algorithm framework.Hence, the main theme of this work is to balance feasibility and cost of solutions.In particular, co-operative co-evolution with hierarchical sub-populations, problem structure exploiting repair schemes and indirect genetic algorithms with self-adjusting decoder functions are identified as promising approaches.The research starts by applying standard genetic algorithms to the problems and explaining the failure of such approaches due to epistasis.To overcome this, problem-specific information is added in a variety of ways, some of which are designed to increase the number of feasible solutions found whilst others are intended to improve the quality of such solutions.As well as a theoretical discussion as to the underlying reasons for using each operator,extensive computational experiments are carried out on a variety of data.These show that the indirect approach relies less on problem structure and hence is easier to implement and superior in solution quality.

Effects of open- and self-pollination treatments on genetic estimations in maize diallel experiment

Energy Technology Data Exchange (ETDEWEB)

Kahriman, F.; Egesel, C.O.; Zorlu, E.

2015-07-01

This study investigated the effects of open- and self-pollination treatments on genetic estimations and kernel biochemical content in a maize diallel experiment. A 7×7 complete reciprocal diallel set (7 parents and 42 hybrids) was used as plant material. Measured traits were: kernel weight per plant, protein content, oil content and carbohydrate content. General combining ability (GCA), specific combining ability (SCA), maternal effects (MAT), non-maternal effects (NMAT) and heterosis values were compared in open- and self-pollination treatments for measured traits. Results showed that the pollination treatments had a significant effect on all investigated traits. Parental lines and hybrid combinations gave different responses. Parents had relatively higher protein and oil content in self-pollination but hybrids had lower values in self-pollination compared with open-pollination. A considerable number of genotypes showed significant differences for genetic estimations (GCA, SCA, MAT, NMAT) and heterosis between open- and self-pollination treatments. Overall, findings suggest that evaluation of kernel quality traits should be made on selfed ear samples; however, evaluation for yield should be carried out on open-pollinated samples. (Author)

Own experiences in genetic counselling of radiation exposed persons

International Nuclear Information System (INIS)

Laude, G.; Bruening, L.

1995-01-01

An outline is given of genetic counselling provided to 46 radiation-exposed persons during the period from 1978 to 1994. The radiation exposure had, in most cases, been due to radiation-therapeutic measures (n=22). To a low extent, counselling was carried out because of fear of genetic consequences of the Chernobyl reactor accident (n=11), preceding radiation exposure from X-ray (n=9) and nuclear diagnosis (n=1) as well as occupation radiation exposure (n=3). During counselling, information was given on the genetic risk to be expected, taking into consideration the risk factor that is valid at present and the malformation doubling dose. After performance of radiation therapy, an avoidance of conception for 2 years has been recommended. After termination of this period, in the case of an urgent wish of having children, pregnancy was not discouraged if no further risk factors existed. (orig.) [de

Genome-wide analysis of ivermectin response by Onchocerca volvulus reveals that genetic drift and soft selective sweeps contribute to loss of drug sensitivity.

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Stephen R Doyle

2017-07-01

Full Text Available Treatment of onchocerciasis using mass ivermectin administration has reduced morbidity and transmission throughout Africa and Central/South America. Mass drug administration is likely to exert selection pressure on parasites, and phenotypic and genetic changes in several Onchocerca volvulus populations from Cameroon and Ghana-exposed to more than a decade of regular ivermectin treatment-have raised concern that sub-optimal responses to ivermectin's anti-fecundity effect are becoming more frequent and may spread.Pooled next generation sequencing (Pool-seq was used to characterise genetic diversity within and between 108 adult female worms differing in ivermectin treatment history and response. Genome-wide analyses revealed genetic variation that significantly differentiated good responder (GR and sub-optimal responder (SOR parasites. These variants were not randomly distributed but clustered in ~31 quantitative trait loci (QTLs, with little overlap in putative QTL position and gene content between the two countries. Published candidate ivermectin SOR genes were largely absent in these regions; QTLs differentiating GR and SOR worms were enriched for genes in molecular pathways associated with neurotransmission, development, and stress responses. Finally, single worm genotyping demonstrated that geographic isolation and genetic change over time (in the presence of drug exposure had a significantly greater role in shaping genetic diversity than the evolution of SOR.This study is one of the first genome-wide association analyses in a parasitic nematode, and provides insight into the genomics of ivermectin response and population structure of O. volvulus. We argue that ivermectin response is a polygenically-determined quantitative trait (QT whereby identical or related molecular pathways but not necessarily individual genes are likely to determine the extent of ivermectin response in different parasite populations. Furthermore, we propose that genetic

Genome-wide analysis of ivermectin response by Onchocerca volvulus reveals that genetic drift and soft selective sweeps contribute to loss of drug sensitivity

Science.gov (United States)

Nana-Djeunga, Hugues C.; Kengne-Ouafo, Jonas A.; Pion, Sébastien D. S.; Bopda, Jean; Kamgno, Joseph; Wanji, Samuel; Che, Hua; Kuesel, Annette C.; Walker, Martin; Basáñez, Maria-Gloria; Boakye, Daniel A.; Osei-Atweneboana, Mike Y.; Boussinesq, Michel; Prichard, Roger K.; Grant, Warwick N.

2017-01-01

Background Treatment of onchocerciasis using mass ivermectin administration has reduced morbidity and transmission throughout Africa and Central/South America. Mass drug administration is likely to exert selection pressure on parasites, and phenotypic and genetic changes in several Onchocerca volvulus populations from Cameroon and Ghana—exposed to more than a decade of regular ivermectin treatment—have raised concern that sub-optimal responses to ivermectin's anti-fecundity effect are becoming more frequent and may spread. Methodology/Principal findings Pooled next generation sequencing (Pool-seq) was used to characterise genetic diversity within and between 108 adult female worms differing in ivermectin treatment history and response. Genome-wide analyses revealed genetic variation that significantly differentiated good responder (GR) and sub-optimal responder (SOR) parasites. These variants were not randomly distributed but clustered in ~31 quantitative trait loci (QTLs), with little overlap in putative QTL position and gene content between the two countries. Published candidate ivermectin SOR genes were largely absent in these regions; QTLs differentiating GR and SOR worms were enriched for genes in molecular pathways associated with neurotransmission, development, and stress responses. Finally, single worm genotyping demonstrated that geographic isolation and genetic change over time (in the presence of drug exposure) had a significantly greater role in shaping genetic diversity than the evolution of SOR. Conclusions/Significance This study is one of the first genome-wide association analyses in a parasitic nematode, and provides insight into the genomics of ivermectin response and population structure of O. volvulus. We argue that ivermectin response is a polygenically-determined quantitative trait (QT) whereby identical or related molecular pathways but not necessarily individual genes are likely to determine the extent of ivermectin response in different

Genetic Diversity and Structure of Natural Quercus variabilis Population in China as Revealed by Microsatellites Markers

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Xiaomeng Shi

2017-12-01

Full Text Available Quercus variabilis is a tree species of ecological and economic value that is widely distributed in China. To effectively evaluate, use, and conserve resources, we applied 25 pairs of simple sequence repeat (SSR primers to study its genetic diversity and genetic structure in 19 natural forest or natural secondary forest populations of Q. variabilis (a total of 879 samples. A total of 277 alleles were detected. Overall, the average expected heterozygosity (He was 0.707 and average allelic richness (AR was 7.79. Q. variabilis manifested a loss of heterozygosity, and the mean of inbreeding coefficient (FIS was 0.044. Less differentiation among populations was observed, and the genetic differentiation coefficient (FST was 0.063. Bayesian clustering analysis indicated that the 19 studied populations could be divided into three groups based on their genetic makeup, namely, the Southwest group, Central group, and Northeastern group. The Central group, compared to the populations of the Southwest and Northeast group, showed higher genetic diversities and lower genetic differentiations. As a widely distributed species, the historical migration of Q. variabilis contributed to its genetic differentiation.

Genetic diversity and geographical dispersal in grapevine clones revealed by microsatellite markers.

Science.gov (United States)

Moncada, Ximena; Pelsy, Frédérique; Merdinoglu, Didier; Hinrichsen, Patricio

2006-11-01

Intravarietal genetic diversification associated with geographical dispersal of a vegetatively propagated species was studied using grapevine Vitis vinifera L. 'Cabernet Sauvignon' as a model. Fifty-nine clonal samples obtained from 7 countries (France, Chile, Spain, Australia, Hungary, USA, and Italy) were analyzed using 84 microsatellite markers. Eighteen polymorphic microsatellite loci (21.4%) were detected, finding 22 different genotypes in the population analyzed with a genetic similarity of over 97%. The presence of chimeric clones was evidenced at locus VMC5g7 by means of a segregation analysis of descendants by self-pollination of a triallelic Chilean clone and by somatic embryogenesis analysis, showing a mutation in L2 cell layer. Only 2 clones (obtained from France and Australia) presented the ancestral genotype, and the most divergent genotype was exhibited by another French clone, which had accumulated 5 somatic mutations. The 2 largest populations considered (from France and Chile) showed a clear divergency in the polymorphisms detected. These antecedents enabled the tracing of geographical dispersal with a phylogenetic hypothesis supporting France as the center of origin of diversification of Cabernet Sauvignon. The results obtained could help to explain diversification processes in other grapevine cultivars. The possibility that this kind of genetic variability occurs in other vegetatively propagated species is discussed, focusing on possible fingerprinting applications.

Genetic analysis reveals diversity and genetic relationship among Trichoderma isolates from potting media, cultivated soil and uncultivated soil.

Science.gov (United States)

Al-Sadi, Abdullah M; Al-Oweisi, Fatma A; Edwards, Simon G; Al-Nadabi, Hamed; Al-Fahdi, Ahmed M

2015-07-28

Trichoderma is one of the most common fungi in soil. However, little information is available concerning the diversity of Trichoderma in soil with no previous history of cultivation. This study was conducted to investigate the most common species and the level of genetic relatedness of Trichoderma species from uncultivated soil in relation to cultivated soil and potting media. A total of 24, 15 and 13 Trichoderma isolates were recovered from 84 potting media samples, 45 cultivated soil samples and 65 uncultivated soil samples, respectively. Analysis based on the internal transcribed spacer region of the ribosomal RNA (rRNA) and the translation elongation factor gene (EF1) indicated the presence of 9 Trichoderma species: T. harzianum (16 isolates), T. asperellum (13), T. citrinoviride (9), T. orientalis (3), T. ghanense (3), T. hamatum (3), T. longibrachiatum (2), T. atroviride (2), and T. viride (1). All species were found to occur in potting media samples, while five Trichoderma species were recovered from the cultivated soils and four from the uncultivated soils. AFLP analysis of the 52 Trichoderma isolates produced 52 genotypes and 993 polymorphic loci. Low to moderate levels of genetic diversity were found within populations of Trichoderma species (H = 0.0780 to 0.2208). Analysis of Molecular Variance indicated the presence of very low levels of genetic differentiation (Fst = 0.0002 to 0.0139) among populations of the same Trichoderma species obtained from the potting media, cultivated soil and uncultivated soil. The study provides evidence for occurrence of Trichoderma isolates in soil with no previous history of cultivation. The lack of genetic differentiation among Trichoderma populations from potting media, cultivated soil and uncultivated soil suggests that some factors could have been responsible for moving Trichoderma propagules among the three substrates. The study reports for the first time the presence of 4 Trichoderma species in Oman: T

Population Genetic Structure of Rock Bream (Oplegnathus fasciatus Temminck & Schlegel, 1884) Revealed by mtDNA COI Sequence in Korea and China

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Park, Hyun Suk; Kim, Choong-Gon; Kim, Sung; Park, Yong-Joo; Choi, Hee-Jung; Xiao, Zhizhong; Li, Jun; Xiao, Yongshuang; Lee, Youn-Ho

2018-04-01

The rock bream, Oplegnathus fasciatus, is a common rocky reef game fish in East Asia and recently has become an aquaculture species. Despite its commercial importance, the population genetic structure of this fish species remains poorly understood. In this study, 163 specimens were collected from 6 localities along the coastal waters of Korea and China and their genetic variation was analyzed with mtDNA COI sequences. A total of 34 polymorphic sites were detected which determined 30 haplotypes. The genetic pattern reveals a low level of nucleotide diversity (0.04 ± 0.003) but a high level of haplotype diversity (0.83 ± 0.02). The 30 haplotypes are divided into two major genealogical clades: one that consists of only Zhoushan (ZS, East China Sea) specific haplotypes from the southern East China Sea and the other that consists of the remaining haplotypes from the northern East China Sea, Yellow Sea, Korea Strait, and East Sea/Sea of Japan. The two clades are separated by approximately 330 435 kyBP. Analyses of AMOVA and F st show a significant population differentiation between the ZS sample and the other ones, corroborating separation of the two genealogical clades. Larval dispersal and the fresh Yangtze River plume are invoked as the main determining factors for this population genetic structure of O. fasciatus. Neutrality tests and mismatch distribution analyses indicate late Pleistocene population expansion along the coastal waters of Korea and China approximately 133-183 kyBP during which there were periodic cycles of glaciations and deglaciations. Such population information needs to be taken into account when stock enhancement and conservation measures are implemented for this fisheries species.

Selection for long and short sleep duration in Drosophila melanogaster reveals the complex genetic network underlying natural variation in sleep.

Science.gov (United States)

Harbison, Susan T; Serrano Negron, Yazmin L; Hansen, Nancy F; Lobell, Amanda S

2017-12-01

Why do some individuals need more sleep than others? Forward mutagenesis screens in flies using engineered mutations have established a clear genetic component to sleep duration, revealing mutants that convey very long or short sleep. Whether such extreme long or short sleep could exist in natural populations was unknown. We applied artificial selection for high and low night sleep duration to an outbred population of Drosophila melanogaster for 13 generations. At the end of the selection procedure, night sleep duration diverged by 9.97 hours in the long and short sleeper populations, and 24-hour sleep was reduced to 3.3 hours in the short sleepers. Neither long nor short sleeper lifespan differed appreciably from controls, suggesting little physiological consequences to being an extreme long or short sleeper. Whole genome sequence data from seven generations of selection revealed several hundred thousand changes in allele frequencies at polymorphic loci across the genome. Combining the data from long and short sleeper populations across generations in a logistic regression implicated 126 polymorphisms in 80 candidate genes, and we confirmed three of these genes and a larger genomic region with mutant and chromosomal deficiency tests, respectively. Many of these genes could be connected in a single network based on previously known physical and genetic interactions. Candidate genes have known roles in several classic, highly conserved developmental and signaling pathways-EGFR, Wnt, Hippo, and MAPK. The involvement of highly pleiotropic pathway genes suggests that sleep duration in natural populations can be influenced by a wide variety of biological processes, which may be why the purpose of sleep has been so elusive.

Selection for long and short sleep duration in Drosophila melanogaster reveals the complex genetic network underlying natural variation in sleep.

Directory of Open Access Journals (Sweden)

Susan T Harbison

2017-12-01

Full Text Available Why do some individuals need more sleep than others? Forward mutagenesis screens in flies using engineered mutations have established a clear genetic component to sleep duration, revealing mutants that convey very long or short sleep. Whether such extreme long or short sleep could exist in natural populations was unknown. We applied artificial selection for high and low night sleep duration to an outbred population of Drosophila melanogaster for 13 generations. At the end of the selection procedure, night sleep duration diverged by 9.97 hours in the long and short sleeper populations, and 24-hour sleep was reduced to 3.3 hours in the short sleepers. Neither long nor short sleeper lifespan differed appreciably from controls, suggesting little physiological consequences to being an extreme long or short sleeper. Whole genome sequence data from seven generations of selection revealed several hundred thousand changes in allele frequencies at polymorphic loci across the genome. Combining the data from long and short sleeper populations across generations in a logistic regression implicated 126 polymorphisms in 80 candidate genes, and we confirmed three of these genes and a larger genomic region with mutant and chromosomal deficiency tests, respectively. Many of these genes could be connected in a single network based on previously known physical and genetic interactions. Candidate genes have known roles in several classic, highly conserved developmental and signaling pathways-EGFR, Wnt, Hippo, and MAPK. The involvement of highly pleiotropic pathway genes suggests that sleep duration in natural populations can be influenced by a wide variety of biological processes, which may be why the purpose of sleep has been so elusive.

Genetic analysis in Bartter syndrome from India.

Science.gov (United States)

Sharma, Pradeep Kumar; Saikia, Bhaskar; Sharma, Rachna; Ankur, Kumar; Khilnani, Praveen; Aggarwal, Vinay Kumar; Cheong, Hae

2014-10-01

Bartter syndrome is a group of inherited, salt-losing tubulopathies presenting as hypokalemic metabolic alkalosis with normotensive hyperreninemia and hyperaldosteronism. Around 150 cases have been reported in literature till now. Mutations leading to salt losing tubulopathies are not routinely tested in Indian population. The authors have done the genetic analysis for the first time in the Bartter syndrome on two cases from India. First case was antenatal Bartter syndrome presenting with massive polyuria and hyperkalemia. Mutational analysis revealed compound heterozygous mutations in KCNJ1(ROMK) gene [p(Leu220Phe), p(Thr191Pro)]. Second case had a phenotypic presentation of classical Bartter syndrome however, genetic analysis revealed only heterozygous novel mutation in SLC12A gene p(Ala232Thr). Bartter syndrome is a clinical diagnosis and genetic analysis is recommended for prognostication and genetic counseling.

Neurog1 Genetic Inducible Fate Mapping (GIFM) Reveals the Existence of Complex Spatiotemporal Cyto-Architectures in the Developing Cerebellum.

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Obana, Edwin A; Lundell, Travis G; Yi, Kevin J; Radomski, Kryslaine L; Zhou, Qiong; Doughty, Martin L

2015-06-01

Neurog1 is a pro-neural basic helix-loop-helix (bHLH) transcription factor expressed in progenitor cells located in the ventricular zone and subsequently the presumptive white matter tracts of the developing mouse cerebellum. We used genetic inducible fate mapping (GIFM) with a transgenic Neurog1-CreER allele to characterize the contributions of Neurog1 lineages to cerebellar circuit formation in mice. GIFM reveals Neurog1-expressing progenitors are fate-mapped to become Purkinje cells and all GABAergic interneuron cell types of the cerebellar cortex but not glia. The spatiotemporal sequence of GIFM is unique to each neuronal cell type. GIFM on embryonic days (E) 10.5 to E12.5 labels Purkinje cells with different medial-lateral settling patterns depending on the day of tamoxifen delivery. GIFM on E11.5 to P7 labels interneurons and the timing of tamoxifen administration correlates with the final inside-to-outside resting position of GABAergic interneurons in the cerebellar cortex. Proliferative status and long-term BrdU retention of GIFM lineages reveals Purkinje cells express Neurog1 around the time they become post-mitotic. In contrast, GIFM labels mitotic and post-mitotic interneurons. Neurog1-CreER GIFM reveals a correlation between the timing of Neurog1 expression and the spatial organization of GABAergic neurons in the cerebellar cortex with possible implications for cerebellar circuit assembly.

Multiple surveys employing a new sample-processing protocol reveal the genetic diversity of placozoans in Japan.

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Miyazawa, Hideyuki; Nakano, Hiroaki

2018-03-01

Placozoans, flat free-living marine invertebrates, possess an extremely simple bauplan lacking neurons and muscle cells and represent one of the earliest-branching metazoan phyla. They are widely distributed from temperate to tropical oceans. Based on mitochondrial 16S rRNA sequences, 19 haplotypes forming seven distinct clades have been reported in placozoans to date. In Japan, placozoans have been found at nine locations, but 16S genotyping has been performed at only two of these locations. Here, we propose a new processing protocol, "ethanol-treated substrate sampling," for collecting placozoans from natural environments. We also report the collection of placozoans from three new locations, the islands of Shikine-jima, Chichi-jima, and Haha-jima, and we present the distribution of the 16S haplotypes of placozoans in Japan. Multiple surveys conducted at multiple locations yielded five haplotypes that were not reported previously, revealing high genetic diversity in Japan, especially at Shimoda and Shikine-jima Island. The observed geographic distribution patterns were different among haplotypes; some were widely distributed, while others were sampled only from a single location. However, samplings conducted on different dates at the same sites yielded different haplotypes, suggesting that placozoans of a given haplotype do not inhabit the same site constantly throughout the year. Continued sampling efforts conducted during all seasons at multiple locations worldwide and the development of molecular markers within the haplotypes are needed to reveal the geographic distribution pattern and dispersal history of placozoans in greater detail.

New developments in genetics of myositis.

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Rothwell, Simon; Lamb, Janine A; Chinoy, Hector

2016-11-01

This article reviews the advances that have been made in our understanding of the genetics of the idiopathic inflammatory myopathies (IIM) in the past 2 years, with a particular focus on polymyositis, dermatomyositis and inclusion body myositis. Two large human leukocyte antigen (HLA) imputation studies have confirmed a strong association with the 8.1 ancestral haplotype in clinical subgroups of myositis and suggest multiple independent associations on this haplotype. Risk in these genes may be due to specific amino acid positions within the peptide-binding grooves of HLA molecules. A large genetic study in 2566 IIM patients revealed associations such as PTPN22, STAT4, UBE2L3 and BLK, which overlap with risk variants reported in other seropositive autoimmune diseases. There is also evidence of different genetic architectures in clinical subgroups of IIM. Candidate gene studies in the Japanese and Chinese populations have replicated previous IIM associations which suggest common aetiology between ethnicities. International collaborations have facilitated large genetic studies in IIM that have revealed much about the genetics of this rare complex disease both within the HLA region and genome-wide. Future approaches, such as sequencing and trans-ethnic meta-analyses, will advance our knowledge of IIM genetics.

Analysis of genetic diversity inpigeonpeagermplasm using ...

Indian Academy of Sciences (India)

Navya

2016-11-25

Nov 25, 2016 ... accessions from Orissa (105) and AP (15) do not group with any Indian accessions. ... In the present work, comparison between SSAP and REMAP revealed ... (sequence-specific amplified polymorphism) for genetic analysis of sweet potato. ... Sharma,V.and Nandinemi, M.R. 2014 Assessment of genetic ...

The synthesis paradigm in genetics.

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Rice, William R

2014-02-01

Experimental genetics with model organisms and mathematically explicit genetic theory are generally considered to be the major paradigms by which progress in genetics is achieved. Here I argue that this view is incomplete and that pivotal advances in genetics--and other fields of biology--are also made by synthesizing disparate threads of extant information rather than generating new information from experiments or formal theory. Because of the explosive expansion of information in numerous "-omics" data banks, and the fragmentation of genetics into numerous subdisciplines, the importance of the synthesis paradigm will likely expand with time.

Genetics of hybrid male sterility between drosophila sibling species: a complex web of epistasis is revealed in interspecific studies.

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Palopoli, M F; Wu, C I

1994-10-01

To study the genetic differences responsible for the sterility of their male hybrids, we introgressed small segments of an X chromosome from Drosophila simulans into a pure Drosophila mauritiana genetic background, then assessed the fertility of males carrying heterospecific introgressions of varying size. Although this analysis examined less than 20% of the X chromosome (roughly 5% of the euchromatic portion of the D. simulans genome), and the segments were introgressed in only one direction, a minimum of four factors that contribute to hybrid male sterility were revealed. At least two of the factors exhibited strong epistasis: males carrying either factor alone were consistently fertile, whereas males carrying both factors together were always sterile. Distinct spermatogenic phenotypes were observed for sterile introgressions of different lengths, and it appeared that an interaction between introgressed segments also influenced the stage of spermatogenic defect. Males with one category of introgression often produced large quantities of motile sperm and were observed copulating, but never inseminated females. Evidently these two species have diverged at a large number of loci which have varied effects on hybrid male fertility. By extrapolation, we estimate that there are at least 40 such loci on the X chromosome alone. Because these species exhibit little DNA-sequence divergence at arbitrarily chosen loci, it seems unlikely that the extensive functional divergence observed could be due mainly to random genetic drift. Significant epistasis between conspecific genes appears to be a common component of hybrid sterility between recently diverged species of Drosophila. The linkage relationships of interacting factors could shed light on the role played by epistatic selection in the dynamics of the allele substitutions responsible for reproductive barriers between species.

Functional genetic divergence in high CO2 adapted Emiliania huxleyi populations.

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Lohbeck, Kai T; Riebesell, Ulf; Collins, Sinéad; Reusch, Thorsten B H

2013-07-01

Predicting the impacts of environmental change on marine organisms, food webs, and biogeochemical cycles presently relies almost exclusively on short-term physiological studies, while the possibility of adaptive evolution is often ignored. Here, we assess adaptive evolution in the coccolithophore Emiliania huxleyi, a well-established model species in biological oceanography, in response to ocean acidification. We previously demonstrated that this globally important marine phytoplankton species adapts within 500 generations to elevated CO2 . After 750 and 1000 generations, no further fitness increase occurred, and we observed phenotypic convergence between replicate populations. We then exposed adapted populations to two novel environments to investigate whether or not the underlying basis for high CO2 -adaptation involves functional genetic divergence, assuming that different novel mutations become apparent via divergent pleiotropic effects. The novel environment "high light" did not reveal such genetic divergence whereas growth in a low-salinity environment revealed strong pleiotropic effects in high CO2 adapted populations, indicating divergent genetic bases for adaptation to high CO2 . This suggests that pleiotropy plays an important role in adaptation of natural E. huxleyi populations to ocean acidification. Our study highlights the potential mutual benefits for oceanography and evolutionary biology of using ecologically important marine phytoplankton for microbial evolution experiments. © 2012 The Author(s). Evolution © 2012 The Society for the Study of Evolution.

Genetic Sharing with Cardiovascular Disease Risk Factors and Diabetes Reveals Novel Bone Mineral Density Loci.

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Sjur Reppe

Full Text Available Bone Mineral Density (BMD is a highly heritable trait, but genome-wide association studies have identified few genetic risk factors. Epidemiological studies suggest associations between BMD and several traits and diseases, but the nature of the suggestive comorbidity is still unknown. We used a novel genetic pleiotropy-informed conditional False Discovery Rate (FDR method to identify single nucleotide polymorphisms (SNPs associated with BMD by leveraging cardiovascular disease (CVD associated disorders and metabolic traits. By conditioning on SNPs associated with the CVD-related phenotypes, type 1 diabetes, type 2 diabetes, systolic blood pressure, diastolic blood pressure, high density lipoprotein, low density lipoprotein, triglycerides and waist hip ratio, we identified 65 novel independent BMD loci (26 with femoral neck BMD and 47 with lumbar spine BMD at conditional FDR < 0.01. Many of the loci were confirmed in genetic expression studies. Genes validated at the mRNA levels were characteristic for the osteoblast/osteocyte lineage, Wnt signaling pathway and bone metabolism. The results provide new insight into genetic mechanisms of variability in BMD, and a better understanding of the genetic underpinnings of clinical comorbidity.

A maize introgression library reveals ample genetic variability for root architecture, water use efficiency and grain yield under different water regimes

OpenAIRE

Salvi, S.; Giuliani, S.; Cané, M.; Sciara, G.; Bovina, R.; Welcker, Claude; Cabrera Bosquet, Llorenç; Grau, Antonin; Tardieu, Francois; Meriggi, P.

2015-01-01

The genetic dissection of root system architecture (RSA) provides valuable opportunities towards a better understanding of its role in determining yield under different water regimes. To this end, a maize introgression library comprised of 75 BC5 lines derived from the cross between Gaspé Flint (an early line; donor parent) and B73 (an elite line; recurrent parent) were evaluated in two experiments conducted under well-watered and water-deficit conditions (WW and WD, respectively) in order to...

Genetic diversity among silkworm (Bombyx mori L., Lep., Bombycidae) germplasms revealed by microsatellites.

Science.gov (United States)

Li, Muwang; Shen, Li; Xu, Anying; Miao, Xuexia; Hou, Chengxiang; Sun, Pingjiang; Zhang, Yuehua; Huang, Yongping

2005-10-01

To determine genetic relationships among strains of silkworm, Bombyx mori L., 31 strains with different origins, number of generations per year, number of molts per generation, and morphological characters were studied using simple sequence repeat (SSR) markers. Twenty-six primer pairs flanking microsatellite sequences in the silkworm genome were assayed. All were polymorphic and unambiguously separated silkworm strains from each other. A total of 188 alleles were detected with a mean value of 7.2 alleles/locus (range 2-17). The average heterozygosity value for each SSR locus ranged from 0 to 0.60, and the highest one was 0.96 (Fl0516 in 4013). The mean polymorphism index content (PIC) was 0.66 (range 0.12-0.89). Unweighted pair group method with arithmetic means (UPGMA) cluster analysis of Nei's genetic distance grouped silkworm strains based on their origin. Seven major ecotypic silkworm groups were analyzed. Principal components analysis (PCA) for SSR data support their UPGMA clustering. The results indicated that SSR markers are an efficient tool for fingerprinting cultivars and conducting genetic-diversity studies in the silkworm.

Genetic and genomic diversity studies of Acacia symbionts in Senegal reveal new species of Mesorhizobium with a putative geographical pattern.

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Fatou Diouf

Full Text Available Acacia senegal (L Willd. and Acacia seyal Del. are highly nitrogen-fixing and moderately salt tolerant species. In this study we focused on the genetic and genomic diversity of Acacia mesorhizobia symbionts from diverse origins in Senegal and investigated possible correlations between the genetic diversity of the strains, their soil of origin, and their tolerance to salinity. We first performed a multi-locus sequence analysis on five markers gene fragments on a collection of 47 mesorhizobia strains of A. senegal and A. seyal from 8 localities. Most of the strains (60% clustered with the M. plurifarium type strain ORS 1032T, while the others form four new clades (MSP1 to MSP4. We sequenced and assembled seven draft genomes: four in the M. plurifarium clade (ORS3356, ORS3365, STM8773 and ORS1032T, one in MSP1 (STM8789, MSP2 (ORS3359 and MSP3 (ORS3324. The average nucleotide identities between these genomes together with the MLSA analysis reveal three new species of Mesorhizobium. A great variability of salt tolerance was found among the strains with a lack of correlation between the genetic diversity of mesorhizobia, their salt tolerance and the soils samples characteristics. A putative geographical pattern of A. senegal symbionts between the dryland north part and the center of Senegal was found, reflecting adaptations to specific local conditions such as the water regime. However, the presence of salt does not seem to be an important structuring factor of Mesorhizobium species.

Mark-recapture using tetracycline and genetics reveal record-high bear density

Science.gov (United States)

Peacock, E.; Titus, K.; Garshelis, D.L.; Peacock, M.M.; Kuc, M.

2011-01-01

We used tetracycline biomarking, augmented with genetic methods to estimate the size of an American black bear (Ursus americanus) population on an island in Southeast Alaska. We marked 132 and 189 bears that consumed remote, tetracycline-laced baits in 2 different years, respectively, and observed 39 marks in 692 bone samples subsequently collected from hunters. We genetically analyzed hair samples from bait sites to determine the sex of marked bears, facilitating derivation of sex-specific population estimates. We obtained harvest samples from beyond the study area to correct for emigration. We estimated a density of 155 independent bears/100 km2, which is equivalent to the highest recorded for this species. This high density appears to be maintained by abundant, accessible natural food. Our population estimate (approx. 1,000 bears) could be used as a baseline and to set hunting quotas. The refined biomarking method for abundance estimation is a useful alternative where physical captures or DNA-based estimates are precluded by cost or logistics. Copyright ?? 2011 The Wildlife Society.

Genetic diversity and structure analysis in wild and landraces of barley from Jordan by using ISJ markers

International Nuclear Information System (INIS)

Baloch, A. W.; Balogh, M. J.; Baloch, M.; Baloch, I. A.

2016-01-01

The present experiment was carried out to estimate genetic diversity and genetic structure in cultivated and wild barley populations collected from Jordan which is considered as primary gene pool of barley. In a total, 94 cultivated barley accessions composed of 4 populations and 52 wild barley accessions consisted of 3 populations were used for genetic analysis using 7 Intron Splice Junction (ISJ) markers. The genetic diversity index (He) of cultivated barley ranged between 0.049 and 0.060; whereas that of wild barley populations ranged between 0.084 and 0.146, suggesting that wild resources of barley harbored greater genetic diversity than its domesticated counterpart, reflecting that barley domestication occurred with genetic bottleneck. Analysis of molecular variance showed high genetic variations among rather than within populations, referring that high genetic differentiation of barley populations caused by genetic and geographical separation of the populations in the harsh growing conditions of Fertile Crescent. Principal coordinate, clustering and structure analysis not only separated cultivated and wild barley, but also each single population, showing their genetic basis and original sample site. The obtained Results also revealed that there is lesser genetic communication between cultivated and wild barley under natural environments. The current findings can better be exploited for collection and utilization of plant germplasms. (author)

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics; Volume 96; Online resources. Low genetic diversity of the endangered Indian wild ass Equus hemionus khur, as revealed by microsatellite analyses. DEVENDRA KHAIRE ASHWIN ATKULWAR SAMEERA FARAH MUMTAZ BAIG. Online Resource Volume 96 Online resources 2017 pp ...

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics. P. VIJAYAGOPAL. Articles written in Journal of Genetics. Volume 97 Issue 1 March 2018 pp 179-187 RESEARCH ARTICLE. Mitochondrial signatures revealed panmixia in Lutjanus argentimaculatus (Forsskål 1775) · A. GOPALAKRISHNAN N. VINEESH SHIHAB ISMAIL MUKTHA ...

CRISPR/Cas9 and active genetics-based trans-species replacement of the endogenous Drosophila kni-L2 CRM reveals unexpected complexity.

Science.gov (United States)

Xu, Xiang-Ru Shannon; Gantz, Valentino Matteo; Siomava, Natalia; Bier, Ethan

2017-12-23

The knirps ( kni ) locus encodes transcription factors required for induction of the L2 wing vein in Drosophila . Here, we employ diverse CRISPR/Cas9 genome editing tools to generate a series of targeted lesions within the endogenous cis-regulatory module (CRM) required for kni expression in the L2 vein primordium. Phenotypic analysis of these ' in locus ' mutations based on both expression of Kni protein and adult wing phenotypes, reveals novel unexpected features of L2-CRM function including evidence for a chromosome pairing-dependent process that promotes transcription. We also demonstrate that self-propagating active genetic elements (CopyCat elements) can efficiently delete and replace the L2-CRM with orthologous sequences from other divergent fly species. Wing vein phenotypes resulting from these trans-species enhancer replacements parallel features of the respective donor fly species. This highly sensitive phenotypic readout of enhancer function in a native genomic context reveals novel features of CRM function undetected by traditional reporter gene analysis. © 2017, Xu et al.

Establishing a Cancer Genetics Programme in Asia - the Singapore Experience

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Chieng Wei-Shieng

2006-06-01

Full Text Available Abstract Cancer genetics is now an established oncology subspecialty with the primary prevention role of identifying high-risk individuals through genetic information for enrolment into screening and preventive programmes. Integrated into major Western centres since the late 1990s, such a programme has been established in Singapore since 2001. Our programme has evaluated 367 index patients comprising mainly breast and colorectal cancer cases. Cancer patients were receptive to genetic counselling, but cost posed a major barrier to genetic testing. However, when the cost barrier was removed through government subsidy plans, more than half of high-risk patients still declined testing. The major barriers were reluctance to involve family members, perception that the information would not change management, and fears of negative feelings. Confirmed mutation carriers were compliant to screening and receptive to prophylactic surgery. Uptake of predictive testing among cancer-free family members has been low, possibly arising from the stigma associated with cancer in our Asian culture. These potential barriers are being addressed through government subsidy plans, continuing education to increase awareness, and being culturally sensitive when dealing with the Asian family.

Comparative Genomics Revealed Genetic Diversity and Species/Strain-Level Differences in Carbohydrate Metabolism of Three Probiotic Bifidobacterial Species

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Toshitaka Odamaki

2015-01-01

Full Text Available Strains of Bifidobacterium longum, Bifidobacterium breve, and Bifidobacterium animalis are widely used as probiotics in the food industry. Although numerous studies have revealed the properties and functionality of these strains, it is uncertain whether these characteristics are species common or strain specific. To address this issue, we performed a comparative genomic analysis of 49 strains belonging to these three bifidobacterial species to describe their genetic diversity and to evaluate species-level differences. There were 166 common clusters between strains of B. breve and B. longum, whereas there were nine common clusters between strains of B. animalis and B. longum and four common clusters between strains of B. animalis and B. breve. Further analysis focused on carbohydrate metabolism revealed the existence of certain strain-dependent genes, such as those encoding enzymes for host glycan utilisation or certain membrane transporters, and many genes commonly distributed at the species level, as was previously reported in studies with limited strains. As B. longum and B. breve are human-residential bifidobacteria (HRB, whereas B. animalis is a non-HRB species, several of the differences in these species’ gene distributions might be the result of their adaptations to the nutrient environment. This information may aid both in selecting probiotic candidates and in understanding their potential function as probiotics.

Isocost Lines Describe the Cellular Economy of Genetic Circuits.

Science.gov (United States)

Gyorgy, Andras; Jiménez, José I; Yazbek, John; Huang, Hsin-Ho; Chung, Hattie; Weiss, Ron; Del Vecchio, Domitilla

2015-08-04

Genetic circuits in living cells share transcriptional and translational resources that are available in limited amounts. This leads to unexpected couplings among seemingly unconnected modules, which result in poorly predictable circuit behavior. In this study, we determine these interdependencies between products of different genes by characterizing the economy of how transcriptional and translational resources are allocated to the production of proteins in genetic circuits. We discover that, when expressed from the same plasmid, the combinations of attainable protein concentrations are constrained by a linear relationship, which can be interpreted as an isocost line, a concept used in microeconomics. We created a library of circuits with two reporter genes, one constitutive and the other inducible in the same plasmid, without a regulatory path between them. In agreement with the model predictions, experiments reveal that the isocost line rotates when changing the ribosome binding site strength of the inducible gene and shifts when modifying the plasmid copy number. These results demonstrate that isocost lines can be employed to predict how genetic circuits become coupled when sharing resources and provide design guidelines for minimizing the effects of such couplings. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Genetic diversity, structure and differentiation in cultivate walnut (Juglans regia L.)

Science.gov (United States)

M. Aradhya; K. Woeste; D. Velasco

2012-01-01

An analysis of genetic structure and differentiation in cultivated walnut (Juglans regia) using 15 microsatellite loci revealed a considerable amount of genetic variation with a mild genetic structure indicating five genetic groups corresponding to the centers of diversity within the home range of walnut in Eurasia. Despite the narrow genetic...

Use of modern tomato breeding germplasm for deciphering the genetic control of agronomical traits by Genome Wide Association study.

Science.gov (United States)

Bauchet, Guillaume; Grenier, Stéphane; Samson, Nicolas; Bonnet, Julien; Grivet, Laurent; Causse, Mathilde

2017-05-01

A panel of 300 tomato accessions including breeding materials was built and characterized with >11,000 SNP. A population structure in six subgroups was identified. Strong heterogeneity in linkage disequilibrium and recombination landscape among groups and chromosomes was shown. GWAS identified several associations for fruit weight, earliness and plant growth. Genome-wide association studies (GWAS) have become a method of choice in quantitative trait dissection. First limited to highly polymorphic and outcrossing species, it is now applied in horticultural crops, notably in tomato. Until now GWAS in tomato has been performed on panels of heirloom and wild accessions. Using modern breeding materials would be of direct interest for breeding purpose. To implement GWAS on a large panel of 300 tomato accessions including 168 breeding lines, this study assessed the genetic diversity and linkage disequilibrium decay and revealed the population structure and performed GWA experiment. Genetic diversity and population structure analyses were based on molecular markers (>11,000 SNP) covering the whole genome. Six genetic subgroups were revealed and associated to traits of agronomical interest, such as fruit weight and disease resistance. Estimates of linkage disequilibrium highlighted the heterogeneity of its decay among genetic subgroups. Haplotype definition allowed a fine characterization of the groups and their recombination landscape revealing the patterns of admixture along the genome. Selection footprints showed results in congruence with introgressions. Taken together, all these elements refined our knowledge of the genetic material included in this panel and allowed the identification of several associations for fruit weight, plant growth and earliness, deciphering the genetic architecture of these complex traits and identifying several new loci useful for tomato breeding.

Assessment of a Competency-Based Undergraduate Course on Genetic and Genomics.

Science.gov (United States)

Kronk, Rebecca; Colbert, Alison; Lengetti, Evelyn

2017-08-24

In response to new demands in the nursing profession, an innovative undergraduate genetics course was designed based on the Essential Nursing Competencies and Curricula Guidelines for Genetics and Genomics. Reflective journaling and storytelling were used as major pedagogies, alongside more traditional approaches. Thematic content analysis of student reflections revealed transformational learning as the major theme emerging from genomic and genetic knowledge acquisition. Quantitative analyses of precourse/postcourse student self-assessments of competencies revealed significant findings.

Genetic diversity of sea-island cotton (Gossypium barbadense) revealed by mapped SSRs.

Science.gov (United States)

Wang, X Q; Feng, C H; Lin, Z X; Zhang, X L

2011-12-08

In order to evaluate the genetic diversity of sea-island cotton (Gossypium barbadense), 237 commonly mapped SSR markers covering the cotton genome were used to genotype 56 sea-island cotton accessions. A total of 218 polymorphic primer pairs (91.98%) amplified 361 loci, with a mean of 1.66 loci. Polymorphism information content values of the SSR primers ranged from 0.035 to 0.862, with a mean of 0.320. The highest mean polymorphism information content value for the SSR motifs was from a compound motif (0.402), and for the chromosomes it was Chr10 (0.589); the highest ratio of polymorphic primers in Xinjiang accessions was from Chr21 (83.33%). Genetic diversity was high in Xinjiang accessions. AMOVA showed that variation was 8 and 92% among populations and within populations, respectively. The 56 sea-island accessions were divided into three groups in the UPGMA dendrogram: Xinhai5 was in the first group; accessions from Xinjiang, except the five main ones, were in the second group, and the other 34 accessions were in the third group. Accessions from the former Soviet Union and Xinjiang main accessions were closely related. Both PCA and UPGMA confirmed that Xinhai5 was distinct from the other accessions, and accessions from Xinjiang were in an independent group. Given the differences between principal components analysis and UPGMA results, it is necessary to combine molecular markers and pedigree information so that genetic diversity can be objectively analyzed.

A Comparison of Telephone Genetic Counseling and In-Person Genetic Counseling from the Genetic Counselor's Perspective.

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Burgess, Kelly R; Carmany, Erin P; Trepanier, Angela M

2016-02-01

Growing demand for and limited geographic access to genetic counseling services is increasing the need for alternative service delivery models (SDM) like telephone genetic counseling (TGC). Little research has been done on genetic counselors' perspectives of the practice of TGC. We created an anonymous online survey to assess whether telephone genetic counselors believed the tasks identified in the ABGC (American Board of Genetic Counseling) Practice Analysis were performed similarly or differently in TGC compared to in person genetic counseling (IPGC). If there were differences noted, we sought to determine the nature of the differences and if additional training might be needed to address them. Eighty eight genetic counselors with experience in TGC completed some or all of the survey. Respondents identified differences in 13 (14.8%) of the 88 tasks studied. The tasks identified as most different in TGC were: "establishing rapport through verbal and nonverbal interactions" (60.2%; 50/83 respondents identified the task as different), "recognizing factors affecting the counseling interaction" (47.8%; 32/67), "assessing client/family emotions, support, etc." (40.1%; 27/66) and "educating clients about basic genetic concepts" (35.6%; 26/73). A slight majority (53.8%; 35/65) felt additional training was needed to communicate information without visual aids and more effectively perform psychosocial assessments. In summary, although a majority of genetic counseling tasks are performed similarly between TGC and IPGC, TGC counselors recognize that specific training in the TGC model may be needed to address the key differences.

A Behavior-Genetic Study of the Legacy of Early Caregiving Experiences: Academic Skills, Social Competence, and Externalizing Behavior in Kindergarten

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Roisman, Glenn I.; Fraley, R. Chris

2012-01-01

A critique of research examining whether early experiences with primary caregivers are reflected in adaptation is that relevant longitudinal studies have generally not employed genetically informed research designs capable of unconfounding shared genes and environments. Using the twin subsample (N = 485 pairs) of the Early Childhood Longitudinal…

A Shared Genetic Propensity Underlies Experiences of Bullying Victimization in Late Childhood and Self-Rated Paranoid Thinking in Adolescence

Science.gov (United States)

Shakoor, Sania; McGuire, Phillip; Cardno, Alastair G.; Freeman, Daniel; Plomin, Robert; Ronald, Angelica

2015-01-01

Background: Bullying is a risk factor for developing psychotic experiences (PEs). Whether bullying is associated with particular PEs, and the extent to which genes and environments influence the association, are unknown. This study investigated which specific PEs in adolescence are associated with earlier bullying victimization and the genetic and environmental contributions underlying their association. Method: Participants were 4826 twin pairs from a longitudinal community-based twin study in England and Wales who reported on their bullying victimization at the age of 12 years. Measures of specific PEs (self-rated Paranoia, Hallucinations, Cognitive disorganization, Grandiosity, Anhedonia, and parent-rated Negative Symptoms) were recorded at age of 16 years. Results: Childhood bullying victimization was most strongly associated with Paranoia in adolescence (r = .26; P bullying victimization and Paranoia were both heritable (35% and 52%, respectively) with unique environmental influences (39% and 48%, respectively), and bullying victimization showed common environmental influences (26%). The association between bullying victimization and Paranoia operated almost entirely via genetic influences (bivariate heritability = 93%), with considerable genetic overlap (genetic correlation = .55). Conclusion: In contrast to the assumed role of bullying victimization as an environmental trigger, these data suggest that bullying victimization in late childhood is particularly linked to self-rated Paranoia in adolescence via a shared genetic propensity. Clinically, individuals with a history of bullying victimization are predicted to be particularly susceptible to paranoid symptoms. PMID:25323579

Exploring evidence of positive selection reveals genetic basis of meat quality traits in Berkshire pigs through whole genome sequencing.

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Jeong, Hyeonsoo; Song, Ki-Duk; Seo, Minseok; Caetano-Anollés, Kelsey; Kim, Jaemin; Kwak, Woori; Oh, Jae-Don; Kim, EuiSoo; Jeong, Dong Kee; Cho, Seoae; Kim, Heebal; Lee, Hak-Kyo

2015-08-20

Natural and artificial selection following domestication has led to the existence of more than a hundred pig breeds, as well as incredible variation in phenotypic traits. Berkshire pigs are regarded as having superior meat quality compared to other breeds. As the meat production industry seeks selective breeding approaches to improve profitable traits such as meat quality, information about genetic determinants of these traits is in high demand. However, most of the studies have been performed using trained sensory panel analysis without investigating the underlying genetic factors. Here we investigate the relationship between genomic composition and this phenotypic trait by scanning for signatures of positive selection in whole-genome sequencing data. We generated genomes of 10 Berkshire pigs at a total of 100.6 coverage depth, using the Illumina Hiseq2000 platform. Along with the genomes of 11 Landrace and 13 Yorkshire pigs, we identified genomic variants of 18.9 million SNVs and 3.4 million Indels in the mapped regions. We identified several associated genes related to lipid metabolism, intramuscular fatty acid deposition, and muscle fiber type which attribute to pork quality (TG, FABP1, AKIRIN2, GLP2R, TGFBR3, JPH3, ICAM2, and ERN1) by applying between population statistical tests (XP-EHH and XP-CLR). A statistical enrichment test was also conducted to detect breed specific genetic variation. In addition, de novo short sequence read assembly strategy identified several candidate genes (SLC25A14, IGF1, PI4KA, CACNA1A) as also contributing to lipid metabolism. Results revealed several candidate genes involved in Berkshire meat quality; most of these genes are involved in lipid metabolism and intramuscular fat deposition. These results can provide a basis for future research on the genomic characteristics of Berkshire pigs.

Desktop Genetics.

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Hough, Soren H; Ajetunmobi, Ayokunmi; Brody, Leigh; Humphryes-Kirilov, Neil; Perello, Edward

2016-11-01

Desktop Genetics is a bioinformatics company building a gene-editing platform for personalized medicine. The company works with scientists around the world to design and execute state-of-the-art clustered regularly interspaced short palindromic repeats (CRISPR) experiments. Desktop Genetics feeds the lessons learned about experimental intent, single-guide RNA design and data from international genomics projects into a novel CRISPR artificial intelligence system. We believe that machine learning techniques can transform this information into a cognitive therapeutic development tool that will revolutionize medicine.

Significant Locus and Metabolic Genetic Correlations Revealed in Genome-Wide Association Study of Anorexia Nervosa.

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Duncan, Laramie; Yilmaz, Zeynep; Gaspar, Helena; Walters, Raymond; Goldstein, Jackie; Anttila, Verneri; Bulik-Sullivan, Brendan; Ripke, Stephan; Thornton, Laura; Hinney, Anke; Daly, Mark; Sullivan, Patrick F; Zeggini, Eleftheria; Breen, Gerome; Bulik, Cynthia M

2017-09-01

The authors conducted a genome-wide association study of anorexia nervosa and calculated genetic correlations with a series of psychiatric, educational, and metabolic phenotypes. Following uniform quality control and imputation procedures using the 1000 Genomes Project (phase 3) in 12 case-control cohorts comprising 3,495 anorexia nervosa cases and 10,982 controls, the authors performed standard association analysis followed by a meta-analysis across cohorts. Linkage disequilibrium score regression was used to calculate genome-wide common variant heritability (single-nucleotide polymorphism [SNP]-based heritability [h 2 SNP ]), partitioned heritability, and genetic correlations (r g ) between anorexia nervosa and 159 other phenotypes. Results were obtained for 10,641,224 SNPs and insertion-deletion variants with minor allele frequencies >1% and imputation quality scores >0.6. The h 2 SNP of anorexia nervosa was 0.20 (SE=0.02), suggesting that a substantial fraction of the twin-based heritability arises from common genetic variation. The authors identified one genome-wide significant locus on chromosome 12 (rs4622308) in a region harboring a previously reported type 1 diabetes and autoimmune disorder locus. Significant positive genetic correlations were observed between anorexia nervosa and schizophrenia, neuroticism, educational attainment, and high-density lipoprotein cholesterol, and significant negative genetic correlations were observed between anorexia nervosa and body mass index, insulin, glucose, and lipid phenotypes. Anorexia nervosa is a complex heritable phenotype for which this study has uncovered the first genome-wide significant locus. Anorexia nervosa also has large and significant genetic correlations with both psychiatric phenotypes and metabolic traits. The study results encourage a reconceptualization of this frequently lethal disorder as one with both psychiatric and metabolic etiology.

A complex genetic basis to X-linked hybrid male sterility between two species of house mice.

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Good, Jeffrey M; Dean, Matthew D; Nachman, Michael W

2008-08-01

The X chromosome plays a central role in the evolution of reproductive isolation, but few studies have examined the genetic basis of X-linked incompatibilities during the early stages of speciation. We report the results of a large experiment focused on the reciprocal introgression of the X chromosome between two species of house mice, Mus musculus and M. domesticus. Introgression of the M. musculus X chromosome into a wild-derived M. domesticus genetic background produced male-limited sterility, qualitatively consistent with previous experiments using classic inbred strains to represent M. domesticus. The genetic basis of sterility involved a minimum of four X-linked factors. The phenotypic effects of major sterility QTL were largely additive and resulted in complete sterility when combined. No sterility factors were uncovered on the M. domesticus X chromosome. Overall, these results revealed a complex and asymmetric genetic basis to X-linked hybrid male sterility during the early stages of speciation in mice. Combined with data from previous studies, we identify one relatively narrow interval on the M. musculus X chromosome involved in hybrid male sterility. Only a handful of spermatogenic genes are within this region, including one of the most rapidly evolving genes on the mouse X chromosome.

How medical technologies shape the experience of illness.

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Hofmann, Bjørn; Svenaeus, Fredrik

2018-02-03

In this article we explore how diagnostic and therapeutic technologies shape the lived experiences of illness for patients. By analysing a wide range of examples, we identify six ways that technology can (trans)form the experience of illness (and health). First, technology may create awareness of disease by revealing asymptomatic signs or markers (imaging techniques, blood tests). Second, the technology can reveal risk factors for developing diseases (e.g., high blood pressure or genetic tests that reveal risks of falling ill in the future). Third, the technology can affect and change an already present illness experience (e.g., the way blood sugar measurement affects the perceived symptoms of diabetes). Fourth, therapeutic technologies may redefine our experiences of a certain condition as diseased rather than unfortunate (e.g. assisted reproductive technologies or symptom based diagnoses in psychiatry). Fifth, technology influences illness experiences through altering social-cultural norms and values regarding various diagnoses. Sixth, technology influences and changes our experiences of being healthy in contrast and relation to being diseased and ill. This typology of how technology forms illness and related conditions calls for reflection regarding the phenomenology of technology and health. How are medical technologies and their outcomes perceived and understood by patients? The phenomenological way of approaching illness as a lived, bodily being-in-the-world is an important approach for better understanding and evaluating the effects that medical technologies may have on our health, not only in defining, diagnosing, or treating diseases, but also in making us feel more vulnerable and less healthy in different regards.

When the topic is you: genetic counselor responses to prenatal patients' requests for self-disclosure.

Science.gov (United States)

Balcom, Jessica R; Veach, Patricia McCarthy; Bemmels, Heather; Redlinger-Grosse, Krista; LeRoy, Bonnie S

2013-06-01

A limited amount of research indicates patient requests play a major role in genetic counselors' self-disclosure decisions and that disclosure and non-disclosure responses to patient requests may differentially affect genetic counseling processes. Studies further suggest patient requests may be more common in prenatal settings, particularly when counselors are pregnant. Empirical evidence is limited however, concerning the nature of patient requests. This study explored genetic counselors' experiences of prenatal patients' requests for self-disclosure. Four major research questions were: (1) What types of questions do prenatal patients ask that invite self-disclosure?; (2) Do pregnant genetic counselors have unique experiences with prenatal patient disclosure requests?; (3) How do genetic counselors typically respond to disclosure requests?; and (4) What strategies are effective and ineffective in responding to disclosure requests? One hundred seventy-six genetic counselors completed an online survey and 40 also participated in telephone interviews. Inductive analysis of 21 interviews revealed patient questions vary, although questions about counselor demographics are most common, and patients are more likely to ask pregnant counselors questions about their personal pregnancy decisions. Participants reported greater discomfort with self-disclosure requests during pregnancy, yet also disclosing more frequently during pregnancy. Counselor responses included personal self-disclosure, professional self-disclosure, redirection, and declining to disclose. Factors perceived as influencing disclosure included: topic, patient motivations, timing of request, quality of counseling relationship, patient characteristics, and ethical/legal responsibilities. Disclosure practices changed over time for most counselors. Additional findings, practice implications, and research recommendations are discussed.

An in silico approach reveals associations between genetic and epigenetic factors within regulatory elements in B cells from primary Sjögren’s syndrome patients

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Orsia D. Konsta

2015-08-01

Full Text Available Recent advances in genetics have highlighted several regions and candidate genes associated with primary Sjögren's syndrome (SS, a systemic autoimmune epithelitis that combines exocrine gland dysfunctions, and focal lymphocytic infiltrations. In addition to genetic factors, it is now clear that epigenetic deregulations are present during SS and restricted to specific cell type subsets such as lymphocytes and salivary gland epithelial cells. In this study, 72 single nucleotide polymorphisms (SNPs associated with 43 SS gene risk factors were selected from publicly available and peer reviewed literature for further in silico analysis. SS risk variant location was tested revealing a broad distribution in coding sequences (5.6%, intronic sequences (55.6%, upstream/downstream genic regions (30.5%, and intergenic regions (8.3%. Moreover, a significant enrichment of regulatory motifs (promoter, enhancer, insulator, DNAse peak and eQTL characterizes SS risk variants (94.4%. Next, screening SNPs in high linkage disequilibrium (r2 ≥ 0.8 in Caucasians revealed 645 new variants including 5 SNPs with missense mutations, and indicated an enrichment of transcriptionally active motifs according to the cell type (B cells > monocytes > T cells >> A549. Finally, we looked at SS risk variants for histone markers in B cells (GM12878, monocytes (CD14+ and epithelial cells (A548. Active histone markers were associated with SS risk variants at both promoters and enhancers in B cells, and within enhancers in monocytes. In conclusion and based on the obtained in silico results, that need further confirmation, associations were observed between SS genetic risk factors and epigenetic factors and these associations predominate in B cells such as those observed at the FAM167A-BLK locus.

Difficulties in Genetics Problem Solving.

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Tolman, Richard R.

1982-01-01

Examined problem-solving strategies of 30 high school students as they solved genetics problems. Proposes a new sequence of teaching genetics based on results: meiosis, sex chromosomes, sex determination, sex-linked traits, monohybrid and dihybrid crosses (humans), codominance (humans), and Mendel's pea experiments. (JN)

Field cage studies and progressive evaluation of genetically-engineered mosquitoes.

Directory of Open Access Journals (Sweden)

Luca Facchinelli

Full Text Available A genetically-engineered strain of the dengue mosquito vector Aedes aegypti, designated OX3604C, was evaluated in large outdoor cage trials for its potential to improve dengue prevention efforts by inducing population suppression. OX3604C is engineered with a repressible genetic construct that causes a female-specific flightless phenotype. Wild-type females that mate with homozygous OX3604C males will not produce reproductive female offspring. Weekly introductions of OX3604C males eliminated all three targeted Ae. aegypti populations after 10-20 weeks in a previous laboratory cage experiment. As part of the phased, progressive evaluation of this technology, we carried out an assessment in large outdoor field enclosures in dengue endemic southern Mexico.OX3604C males were introduced weekly into field cages containing stable target populations, initially at 10:1 ratios. Statistically significant target population decreases were detected in 4 of 5 treatment cages after 17 weeks, but none of the treatment populations were eliminated. Mating competitiveness experiments, carried out to explore the discrepancy between lab and field cage results revealed a maximum mating disadvantage of up 59.1% for OX3604C males, which accounted for a significant part of the 97% fitness cost predicted by a mathematical model to be necessary to produce the field cage results.Our results indicate that OX3604C may not be effective in large-scale releases. A strain with the same transgene that is not encumbered by a large mating disadvantage, however, could have improved prospects for dengue prevention. Insights from large outdoor cage experiments may provide an important part of the progressive, stepwise evaluation of genetically-engineered mosquitoes.

New gSSR and EST-SSR markers reveal high genetic diversity in the invasive plant Ambrosia artemisiifolia L. and can be transferred to other invasive Ambrosia species.

Science.gov (United States)

Meyer, Lucie; Causse, Romain; Pernin, Fanny; Scalone, Romain; Bailly, Géraldine; Chauvel, Bruno; Délye, Christophe; Le Corre, Valérie

2017-01-01

Ambrosia artemisiifolia L., (common ragweed), is an annual invasive and highly troublesome plant species originating from North America that has become widespread across Europe. New sets of genomic and expressed sequence tag (EST) based simple sequence repeats (SSRs) markers were developed in this species using three approaches. After validation, 13 genomic SSRs and 13 EST-SSRs were retained and used to characterize the genetic diversity and population genetic structure of Ambrosia artemisiifolia populations from the native (North America) and invasive (Europe) ranges of the species. Analysing the mating system based on maternal families did not reveal any departure from complete allogamy and excess homozygosity was mostly due the presence of null alleles. High genetic diversity and patterns of genetic structure in Europe suggest two main introduction events followed by secondary colonization events. Cross-species transferability of the newly developed markers to other invasive species of the Ambrosia genus was assessed. Sixty-five percent and 75% of markers, respectively, were transferable from A. artemisiifolia to Ambrosia psilostachya and Ambrosia tenuifolia. 40% were transferable to Ambrosia trifida, this latter species being seemingly more phylogenetically distantly related to A. artemisiifolia than the former two.

Genetics and Neuromuscular Diseases

Science.gov (United States)

... Testing that reveals a young child’s genet- ic destiny may affect relationships within the family or may ... linked inheritance don’t apply at all. An embryo receives its mitochondria from the mother’s egg cell, ...

Genetic Contributions to Clinical Pain and Analgesia: Avoiding Pitfalls in Genetic Research

Science.gov (United States)

Kim, Hyungsuk; Clark, David; Dionne, Raymond A.

2010-01-01

Understanding the genetic basis of human variations in pain is critical to elucidating the molecular basis of pain sensitivity, variable responses to analgesic drugs, and, ultimately, to individualized treatment of pain and improved public health. With the help of recently accumulated knowledge and advanced technologies, pain researchers hope to gain insight into genetic mechanisms of pain and eventually apply this knowledge to pain treatment. Perspective We critically reviewed the published literature to examine the strength of evidence supporting genetic influences on clinical and human experimental pain. Based on this evidence and the experience of false associations that have occurred in other related disciplines, we provide recommendations for avoiding pitfalls in pain genetic research. PMID:19559388

Experimental Population Genetics in the Introductory Genetics Laboratory Using "Drosophila" as a Model Organism

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Johnson, Ronald; Kennon, Tillman

2009-01-01

Hypotheses of population genetics are derived and tested by students in the introductory genetics laboratory classroom as they explore the effects of biotic variables (physical traits of fruit flies) and abiotic variables (island size and distance) on fruit fly populations. In addition to this hypothesis-driven experiment, the development of…

Genetic variability in Sambucus nigra L. clones : a preliminary ...

Indian Academy of Sciences (India)

c Indian Academy of Sciences. ONLINE ... yield and production evaluations revealed that clones from ..... Population genetic software for teaching and research. Mol. Ecol. ... and genetic evaluation of interspecific hybrids within the genus.

[The genetics of addictions].

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Ibañez Cuadrado, Angela

2008-01-01

The addictions are common chronic psychiatric diseases which represent a serious worldwide public-health problem. They have a high prevalence and negative effects at individual, family and societal level, with a high sanitary cost. Epidemiological genetic research has revealed that addictions are moderately to highly heritable. Also the investigation has evidenced that environmental and genetic factors contribute to individual differences in vulnerability to addictions. Advances in the neurobiology of addiction joined to the development of new molecular genetic technologies, have led to the identification of a variety of underlying genes and pathways in addiction process, leading to the description of common molecular mechanisms in substance and behaviour dependencies. Identifying gene-environment interactions is a crucial issue in future research. Other major goal in genetic research is the identification of new therapeutic targets for treatment and prevention.

Inbred or Outbred? Genetic Diversity in Laboratory Rodent Colonies

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Brekke, Thomas D.; Steele, Katherine A.; Mulley, John F.

2017-01-01

Nonmodel rodents are widely used as subjects for both basic and applied biological research, but the genetic diversity of the study individuals is rarely quantified. University-housed colonies tend to be small and subject to founder effects and genetic drift; so they may be highly inbred or show substantial genetic divergence from other colonies, even those derived from the same source. Disregard for the levels of genetic diversity in an animal colony may result in a failure to replicate results if a different colony is used to repeat an experiment, as different colonies may have fixed alternative variants. Here we use high throughput sequencing to demonstrate genetic divergence in three isolated colonies of Mongolian gerbil (Meriones unguiculatus) even though they were all established recently from the same source. We also show that genetic diversity in allegedly “outbred” colonies of nonmodel rodents (gerbils, hamsters, house mice, deer mice, and rats) varies considerably from nearly no segregating diversity to very high levels of polymorphism. We conclude that genetic divergence in isolated colonies may play an important role in the “replication crisis.” In a more positive light, divergent rodent colonies represent an opportunity to leverage genetically distinct individuals in genetic crossing experiments. In sum, awareness of the genetic diversity of an animal colony is paramount as it allows researchers to properly replicate experiments and also to capitalize on other genetically distinct individuals to explore the genetic basis of a trait. PMID:29242387

Comparison of the effectiveness of ISJ and SSR markers and detection of outlier loci in conservation genetics of Pulsatilla patens populations.

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Bilska, Katarzyna; Szczecińska, Monika

2016-01-01

Research into the protection of rare and endangered plant species involves genetic analyses to determine their genetic variation and genetic structure. Various categories of genetic markers are used for this purpose. Microsatellites, also known as simple sequence repeats (SSR), are the most popular category of markers in population genetics research. In most cases, microsatellites account for a large part of the noncoding DNA and exert a neutral effect on the genome. Neutrality is a desirable feature in evaluations of genetic differences between populations, but it does not support analyses of a population's ability to adapt to a given environment or its evolutionary potential. Despite the numerous advantages of microsatellites, non-neutral markers may supply important information in conservation genetics research. They are used to evaluate adaptation to specific environmental conditions and a population's adaptive potential. The aim of this study was to compare the level of genetic variation in Pulsatilla patens populations revealed by neutral SSR markers and putatively adaptive ISJ markers (intron-exon splice junction). The experiment was conducted on 14 Polish populations of P. patens and three P. patens populations from the nearby region of Vitebsk in Belarus. A total of 345 individuals were examined. Analyses were performed with the use of eight SSR primers specific to P. patens and three ISJ primers. SSR markers revealed a higher level of genetic variation than ISJ markers ( H e = 0.609, H e = 0.145, respectively). An analysis of molecular variance (AMOVA) revealed that, the overall genetic diversity between the analyzed populations defined by parameters F ST and Φ PT for SSR (20%) and Φ PT for ISJ (21%) markers was similar. Analysis conducted in the Structure program divided analyzed populations into two groups (SSR loci) and three groups (ISJ markers). Mantel test revealed correlations between the geographic distance and genetic diversity of Polish

Genetic influences are virtually absent for trust.

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Paul A M Van Lange

Full Text Available Over the past decades, numerous twin studies have revealed moderate to high heritability estimates for individual differences in a wide range of human traits, including cognitive ability, psychiatric disorders, and personality traits. Even factors that are generally believed to be environmental in nature have been shown to be under genetic control, albeit modest. Is such heritability also present in social traits that are conceptualized as causes and consequences of social interactions or in other ways strongly shaped by behavior of other people? Here we examine a population-based sample of 1,012 twins and relatives. We show that the genetic influence on generalized trust in other people (trust-in-others: h2 = 5%, ns, and beliefs regarding other people's trust in the self (trust-in-self: h2 = 13%, ns, is virtually absent. As test-retest reliability for both scales were found to be moderate or high (r = .76 and r = .53, respectively in an independent sample, we conclude that all variance in trust is likely to be accounted for by non-shared environmental influences. We show that, relative to cognitive abilities, psychiatric disorders, and classic personality variables, genetic influences are smaller for trust, and propose that experiences with or observations of the behavior of other people shape trust more strongly than other traits.

Genetic dissection of the Drosophila melanogaster female head transcriptome reveals widespread allelic heterogeneity.

Science.gov (United States)

King, Elizabeth G; Sanderson, Brian J; McNeil, Casey L; Long, Anthony D; Macdonald, Stuart J

2014-05-01

Modern genetic mapping is plagued by the "missing heritability" problem, which refers to the discordance between the estimated heritabilities of quantitative traits and the variance accounted for by mapped causative variants. One major potential explanation for the missing heritability is allelic heterogeneity, in which there are multiple causative variants at each causative gene with only a fraction having been identified. The majority of genome-wide association studies (GWAS) implicitly assume that a single SNP can explain all the variance for a causative locus. However, if allelic heterogeneity is prevalent, a substantial amount of genetic variance will remain unexplained. In this paper, we take a haplotype-based mapping approach and quantify the number of alleles segregating at each locus using a large set of 7922 eQTL contributing to regulatory variation in the Drosophila melanogaster female head. Not only does this study provide a comprehensive eQTL map for a major community genetic resource, the Drosophila Synthetic Population Resource, but it also provides a direct test of the allelic heterogeneity hypothesis. We find that 95% of cis-eQTLs and 78% of trans-eQTLs are due to multiple alleles, demonstrating that allelic heterogeneity is widespread in Drosophila eQTL. Allelic heterogeneity likely contributes significantly to the missing heritability problem common in GWAS studies.

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics. James F. Crow. Articles written in Journal of Genetics. Volume 87 Issue 4 December 2008 pp 349-353 Perspectives. Maintaining evolvability · James F. Crow · More Details Abstract Fulltext PDF. Although molecular methods, such as QTL mapping, have revealed a number of loci with ...

Microsatellite analysis of chloroquine resistance associated alleles and neutral loci reveal genetic structure of Indian Plasmodium falciparum

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Mallick, Prashant K.; Sutton, Patrick L.; Singh, Ruchi; Singh, Om P.; Dash, Aditya P.; Singh, Ashok K.; Carlton, Jane M.; Bhasin, Virendra K.

2013-01-01

Efforts to control malignant malaria caused by Plasmodium falciparum are hampered by the parasite’s acquisition of resistance to antimalarial drugs, e.g., chloroquine. This necessitates evaluating the spread of chloroquine resistance in any malaria-endemic area. India displays highly variable malaria epidemiology and also shares porous international borders with malaria-endemic Southeast Asian countries having multi-drug resistant malaria. Malaria epidemiology in India is believed to be affected by two major factors: high genetic diversity and evolving drug resistance in P. falciparum. How transmission intensity of malaria can influence the genetic structure of chloroquine-resistant P. falciparum population in India is unknown. Here, genetic diversity within and among P. falciparum populations is analyzed with respect to their prevalence and chloroquine resistance observed in 13 different locations in India. Microsatellites developed for P. falciparum, including three putatively neutral and seven microsatellites thought to be under a hitchhiking effect due to chloroquine selection were used. Genetic hitchhiking is observed in five of seven microsatellites flanking the gene responsible for chloroquine resistance. Genetic admixture analysis and F-statistics detected genetically distinct groups in accordance with transmission intensity of different locations and the probable use of chloroquine. A large genetic break between the chloroquine-resistant parasite of the Northeast-East-Island group and Southwest group (FST = 0.253, P<0.001) suggests a long period of isolation or a possibility of different origin between them. A pattern of significant isolation by distance was observed in low transmission areas (r = 0.49, P=0.003, N = 83, Mantel test). An unanticipated pattern of spread of hitchhiking suggests genetic structure for Indian P. falciparum population. Overall, the study suggests that transmission intensity can be an efficient driver for genetic differentiation

Outlier SNP markers reveal fine-scale genetic structuring across European hake populations (Merluccius merluccius)

DEFF Research Database (Denmark)

Milano, I.; Babbucci, M.; Cariani, A.

2014-01-01

fishery. Analysis of 850 individuals from 19 locations across the entire distribution range showed evidence for several outlier loci, with significantly higher resolving power. While 299 putatively neutral SNPs confirmed the genetic break between basins (FCT = 0.016) and weak differentiation within basins...... even when neutral markers provide genetic homogeneity across populations. Here, 381 SNPs located in transcribed regions were used to assess largeand fine-scale population structure in the European hake (Merluccius merluccius), a widely distributed demersal species of high priority for the European...

Genetics of frontotemporal lobar degeneration

Directory of Open Access Journals (Sweden)

Aswathy P

2010-10-01

Full Text Available Frontotemporal lobar degeneration (FTLD is a highly heterogenous group of progressive neurodegenerative disorders characterized by atrophy of prefrontal and anterior temporal cortices. Recently, the research in the field of FTLD has gained increased attention due to the clinical, neuropathological, and genetic heterogeneity and has increased our understanding of the disease pathogenesis. FTLD is a genetically complex disorder. It has a strong genetic basis and 50% of patients show a positive family history for FTLD. Linkage studies have revealed seven chromosomal loci and a number of genes including MAPT, PGRN, VCP, and CHMB-2B are associated with the disease. Neuropathologically, FTLD is classified into tauopathies and ubiquitinopathies. The vast majority of FTLD cases are characterized by pathological accumulation of tau or TDP-43 positive inclusions, each as an outcome of mutations in MAPT or PGRN, respectively. Identification of novel proteins involved in the pathophysiology of the disease, such as progranulin and TDP-43, may prove to be excellent biomarkers of disease progression and thereby lead to the development of better therapeutic options through pharmacogenomics. However, much more dissections into the causative pathways are needed to get a full picture of the etiology. Over the past decade, advances in research on the genetics of FTLD have revealed many pathogenic mutations leading to different clinical manifestations of the disease. This review discusses the current concepts and recent advances in our understanding of the genetics of FTLD.

Microsatellite analysis of chloroquine resistance associated alleles and neutral loci reveal genetic structure of Indian Plasmodium falciparum.

Science.gov (United States)

Mallick, Prashant K; Sutton, Patrick L; Singh, Ruchi; Singh, Om P; Dash, Aditya P; Singh, Ashok K; Carlton, Jane M; Bhasin, Virendra K

2013-10-01

Efforts to control malignant malaria caused by Plasmodium falciparum are hampered by the parasite's acquisition of resistance to antimalarial drugs, e.g., chloroquine. This necessitates evaluating the spread of chloroquine resistance in any malaria-endemic area. India displays highly variable malaria epidemiology and also shares porous international borders with malaria-endemic Southeast Asian countries having multi-drug resistant malaria. Malaria epidemiology in India is believed to be affected by two major factors: high genetic diversity and evolving drug resistance in P. falciparum. How transmission intensity of malaria can influence the genetic structure of chloroquine-resistant P. falciparum population in India is unknown. Here, genetic diversity within and among P. falciparum populations is analyzed with respect to their prevalence and chloroquine resistance observed in 13 different locations in India. Microsatellites developed for P. falciparum, including three putatively neutral and seven microsatellites thought to be under a hitchhiking effect due to chloroquine selection were used. Genetic hitchhiking is observed in five of seven microsatellites flanking the gene responsible for chloroquine resistance. Genetic admixture analysis and F-statistics detected genetically distinct groups in accordance with transmission intensity of different locations and the probable use of chloroquine. A large genetic break between the chloroquine-resistant parasite of the Northeast-East-Island group and Southwest group (FST=0.253, Pstructure for Indian P. falciparum population. Overall, the study suggests that transmission intensity can be an efficient driver for genetic differentiation at both neutral and adaptive loci across India. Copyright © 2013 Elsevier B.V. All rights reserved.

Genetics of nonsyndromic obesity.

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Lee, Yung Seng

2013-12-01

Common obesity is widely regarded as a complex, multifactorial trait influenced by the 'obesogenic' environment, sedentary behavior, and genetic susceptibility contributed by common and rare genetic variants. This review describes the recent advances in understanding the role of genetics in obesity. New susceptibility loci and genetic variants are being uncovered, but the collective effect is relatively small and could not explain most of the BMI heritability. Yet-to-be identified common and rare variants, epistasis, and heritable epigenetic changes may account for part of the 'missing heritability'. Evidence is emerging about the role of epigenetics in determining obesity susceptibility, mediating developmental plasticity, which confers obesity risk from early life experiences. Genetic prediction scores derived from selected genetic variants, and also differential DNA methylation levels and methylation scores, have been shown to correlate with measures of obesity and response to weight loss intervention. Genetic variants, which confer susceptibility to obesity-related morbidities like nonalcoholic fatty liver disease, were also discovered recently. We can expect discovery of more rare genetic variants with the advent of whole exome and genome sequencing, and also greater understanding of epigenetic mechanisms by which environment influences genetic expression and which mediate the gene-environment interaction.

Genetic relatedness of Trichoderma isolates antagonistic against Fusarium oxysporum f.sp. dianthi inflicting carnation wilt.

Science.gov (United States)

Shanmugam, V; Sharma, Vivek; Ananthapadmanaban

2008-01-01

Twenty-eight isolates of Trichoderma belonging to four different species were screened in vitro for their antagonistic ability against Fusarium oxysporum f.sp. dianthi causing carnation wilt. Three different levels of antagonism observed in dual plate assay were further confirmed by cell-free culture filtrate experiments. Isolates showing class I level of antagonism produced maximum lytic enzymes, chitinases and beta-1,3-glucanases. Genetic variability of 25 selected isolates was assessed by random amplified polymorphic DNA technique and the amplified products were correlated for their level of antagonism. Unweighed pair-group method with arithmetical averages cluster analysis revealed prominent inter-and intraspecific genetic variation among the isolates. Based on their genetic relationship, the isolates were mainly distributed into 3 major groups representing T. atroviride, T. pseudokoningii and T. harzianum, with 20-35% interspecific dissimilarity. However, the polymorphism shown by the isolates did not correlate to their level of antagonism.

Early Life Experiences and Exercise Associate with Canine Anxieties.

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Katriina Tiira

Full Text Available Personality and anxiety disorders across species are affected by genetic and environmental factors. Shyness-boldness personality continuum exists across species, including the domestic dog, with a large within- and across-breed variation. Domestic dogs are also diagnosed for several anxiety-related behavioral conditions, such as generalized anxiety disorders, phobias, and separation anxiety. Genetic and environmental factors contributing to personality and anxiety are largely unknown. We collected questionnaire data from a Finnish family dog population (N = 3264 in order to study the associating environmental factors for canine fearfulness, noise sensitivity, and separation anxiety. Early life experiences and exercise were found to associate with anxiety prevalence. We found that fearful dogs had less socialization experiences (p = 0.002 and lower quality of maternal care (p < 0.0001 during puppyhood. Surprisingly, the largest environmental factor associating with noise sensitivity (p < 0.0001 and separation anxiety (p = 0.007 was the amount of daily exercise; dogs with noise sensitivity and separation anxiety had less daily exercise. Our findings suggest that dogs share many of the same environmental factors that contribute to anxiety in other species as well, such as humans and rodents. Our study highlights the importance of early life experiences, especially the quality of maternal care and daily exercise for the welfare and management of the dogs, and reveals important confounding factors to be considered in the genetic characterization of canine anxiety.

Genetic and environmental interactions

International Nuclear Information System (INIS)

Strong, L.C.

1977-01-01

Cancer may result from a multistage process occurring over a long period of time. Presumably, initial and progressive stages of carcinogenesis may be modified by both genetic and environmental factors. Theoretically, genetic factors may alter susceptibility to the carcinogenic effects of an environmental agent at the initial exposure due to variation in metabolism of the carcinogen or variation in specific target cell response to the active carcinogen, or during the latent phase due to numerous factors that might increase the probability of tumor expression, including growth-promoting factors or immunodeficiency states. Observed genetic and environmental interactions in carcinogenesis include an association between genetically determined inducibility of aryl hydrocarbon hydroxylase and smoking-related cancers, familial susceptibility to certain environmental carcinogens, an association between hereditary disorders of mutagenesis and carcinogenesis, and enhancement of tissue-specific, dominantly inherited tumor predisposition by radiation. Multiple primary tumors occur frequently in genetically predisposed individuals. Specific markers for susceptibility must be sought in order that high-risk individuals be identified and appropriate measures taken for early cancer detection or prevention. Study of the nature of the genetically determined susceptibility and interactions with environmental agents may be revealing in the understanding of carcinogenesis in general

Genetic evidence reveals improvement opportunities for tissue preparation in forensic analysis

OpenAIRE

Romero, Rosa Elena; Sandoval, Alejandro; Arango, Juliana; Camargo, Martha Lucia

2016-01-01

Introduction: Paraffin embedded tissues are an excellent alternative to obtain dna, especially when it is not possible to have fresh samples or when the tissue storage and preservation is not feasible; therefore, this sample is the only item available for matching purposes. The success in any genetic analysis implies having adequate tissue fixation and suitable dna extraction methods that allow to obtain good quality and quantity molecules, free of biological, chemical and microbiological con...

Recent advances in epilepsy genetics.

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Orsini, Alessandro; Zara, Federico; Striano, Pasquale

2018-02-22

In last few years there has been rapid increase in the knowledge of epilepsy genetics. Nowadays, it is estimated that genetic epilepsies include over than 30% of all epilepsy syndromes. Several genetic tests are now available for diagnostic purposes in clinical practice. In particular, next-generation sequencing has proven to be effective in revealing gene mutations causing epilepsies in up to a third of the patients. This has lead also to functional studies that have given insight into disease pathophysiology and consequently to the identification of potential therapeutic targets opening the way of precision medicine for epilepsy patients. This minireview is focused on the most recent advances in genetics of epilepsies. We will also overview the modern genomic technologies and illustrate the diagnostic pathways in patients with genetic epilepsies. Finally, the potential implications for a personalized treatment (precision medicine) are also discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Genetic architecture and temporal patterns of biomass accumulation in spring barley revealed by image analysis.

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Neumann, Kerstin; Zhao, Yusheng; Chu, Jianting; Keilwagen, Jens; Reif, Jochen C; Kilian, Benjamin; Graner, Andreas

2017-08-10

Genetic mapping of phenotypic traits generally focuses on a single time point, but biomass accumulates continuously during plant development. Resolution of the temporal dynamics that affect biomass recently became feasible using non-destructive imaging. With the aim to identify key genetic factors for vegetative biomass formation from the seedling stage to flowering, we explored growth over time in a diverse collection of two-rowed spring barley accessions. High heritabilities facilitated the temporal analysis of trait relationships and identification of quantitative trait loci (QTL). Biomass QTL tended to persist only a short period during early growth. More persistent QTL were detected around the booting stage. We identified seven major biomass QTL, which together explain 55% of the genetic variance at the seedling stage, and 43% at the booting stage. Three biomass QTL co-located with genes or QTL involved in phenology. The most important locus for biomass was independent from phenology and is located on chromosome 7HL at 141 cM. This locus explained ~20% of the genetic variance, was significant over a long period of time and co-located with HvDIM, a gene involved in brassinosteroid synthesis. Biomass is a dynamic trait and is therefore orchestrated by different QTL during early and late growth stages. Marker-assisted selection for high biomass at booting stage is most effective by also including favorable alleles from seedling biomass QTL. Selection for dynamic QTL may enhance genetic gain for complex traits such as biomass or, in the future, even grain yield.

Genetics reveal the identity and origin of the lionfish invasion in the Mediterranean Sea.

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Bariche, Michel; Kleitou, Periklis; Kalogirou, Stefanos; Bernardi, Giacomo

2017-07-28

Following aquarium releases, invasive lionfishes have colonized large areas of the Caribbean and western Atlantic, resulting in an immense ecological damage. The early stages of that invasion are poorly known. Indeed, a lag of time between the introduction and detection often preclude genetic characterization of that crucial phase. With elevated awareness, the recent invasion of Pterois miles was quickly detected in the Mediterranean Sea. We hereby show that the very first individuals establishing populations in the Mediterranean Sea display haplotypes that nest within the large genetic diversity of Red Sea individuals, thus indicating an invasion via the Suez Canal. We also show that only two haplotypes are detected in the Mediterranean Sea, suggesting that few individuals may have been involved in the invasion. Thus, we conclude that the Mediterranean invasion is the result of a movement of individuals from the Red Sea, rather than from other means, and that low genetic diversity does not seem to have a negative effect on the success and spread of lionfish into the Mediterranean Sea.

Allele mining in barley genetic resources reveals genes of race-nonspecific powdery mildew resistance

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Annika eSpies

2012-01-01

Full Text Available Race-nonspecific, or quantitative, pathogen resistance is of high importance to plant breeders due to its expected durability. However, it is usually controlled by multiple quantitative trait loci (QTL and therefore difficult to handle in practice. Knowing the genes that underlie race-nonspecific resistance would allow its exploitation in a more targeted manner. Here, we performed an association-genetic study in a customized worlwide collection of spring barley accessions for candidate genes of race-nonspecific resistance to the powdery mildew fungus Blumeria graminis f.sp. hordei (Bgh and combined data with results from QTL-mapping- as well as functional-genomics approaches. This led to the idenfication of 11 associated genes with converging evidence for an important role in race-nonspecific resistance in the presence of the Mlo-gene for basal susceptibility. Outstanding in this respect was the gene encoding the transcription factor WRKY2. The results suggest that unlocking plant genetic resources and integrating functional-genomic with genetic approaches accelerates the discovery of genes underlying race-nonspecific resistance in barley and other crop plants.

Genetic dissection of the Drosophila melanogaster female head transcriptome reveals widespread allelic heterogeneity.

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Elizabeth G King

2014-05-01

Full Text Available Modern genetic mapping is plagued by the "missing heritability" problem, which refers to the discordance between the estimated heritabilities of quantitative traits and the variance accounted for by mapped causative variants. One major potential explanation for the missing heritability is allelic heterogeneity, in which there are multiple causative variants at each causative gene with only a fraction having been identified. The majority of genome-wide association studies (GWAS implicitly assume that a single SNP can explain all the variance for a causative locus. However, if allelic heterogeneity is prevalent, a substantial amount of genetic variance will remain unexplained. In this paper, we take a haplotype-based mapping approach and quantify the number of alleles segregating at each locus using a large set of 7922 eQTL contributing to regulatory variation in the Drosophila melanogaster female head. Not only does this study provide a comprehensive eQTL map for a major community genetic resource, the Drosophila Synthetic Population Resource, but it also provides a direct test of the allelic heterogeneity hypothesis. We find that 95% of cis-eQTLs and 78% of trans-eQTLs are due to multiple alleles, demonstrating that allelic heterogeneity is widespread in Drosophila eQTL. Allelic heterogeneity likely contributes significantly to the missing heritability problem common in GWAS studies.

Genetic divergence of tomato subsamples

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André Pugnal Mattedi

2014-02-01

Full Text Available Understanding the genetic variability of a species is crucial for the progress of a genetic breeding program and requires characterization and evaluation of germplasm. This study aimed to characterize and evaluate 101 tomato subsamples of the Salad group (fresh market and two commercial controls, one of the Salad group (cv. Fanny and another of the Santa Cruz group (cv. Santa Clara. Four experiments were conducted in a randomized block design with three replications and five plants per plot. The joint analysis of variance was performed and characteristics with significant complex interaction between control and experiment were excluded. Subsequently, the multicollinearity diagnostic test was carried out and characteristics that contributed to severe multicollinearity were excluded. The relative importance of each characteristics for genetic divergence was calculated by the Singh's method (Singh, 1981, and the less important ones were excluded according to Garcia (1998. Results showed large genetic divergence among the subsamples for morphological, agronomic and organoleptic characteristics, indicating potential for genetic improvement. The characteristics total soluble solids, mean number of good fruits per plant, endocarp thickness, mean mass of marketable fruit per plant, total acidity, mean number of unmarketable fruit per plant, internode diameter, internode length, main stem thickness and leaf width contributed little to the genetic divergence between the subsamples and may be excluded in future studies.

Chloroplast microsatellites reveal population genetic diversity in red pine, Pinus resinosa Ait

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Craig S. Echt; L.L. DeVerno; M. Anzidei; G.G. Vendramin

1998-01-01

Variation in paternally inherited chloroplast microsatellite (cpSSR) DNA was used to study population genetic structure in red pine (Pinus resinosa Ait.), a species characterized by morphological uniformity, no allozyme variation, and limited RAPD variation. Using nine cpSSR loci, a total of 23 chloroplast haplotypes and 25 cpSSR alleles were were...

The genetic structure of fermentative vineyard-associated Saccharomyces cerevisiae populations revealed by microsatellite analysis.

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Schuller, Dorit; Casal, Margarida

2007-02-01

From the analysis of six polymorphic microsatellite loci performed in 361 Saccharomyces cerevisiae isolates, 93 alleles were identified, 52 of them being described for the first time. All these isolates have a distinct mtDNA RFLP pattern. They are derived from a pool of 1620 isolates obtained from spontaneous fermentations of grapes collected in three vineyards of the Vinho Verde Region in Portugal, during the 2001-2003 harvest seasons. For all loci analyzed, observed heterozygosity was 3-4 times lower than the expected value supposing a Hardy-Weinberg equilibrium (random mating and no evolutionary mechanisms acting), indicating a clonal structure and strong populational substructuring. Genetic differences among S. cerevisiae populations were apparent mainly from gradations in allele frequencies rather than from distinctive "diagnostic" genotypes, and the accumulation of small allele-frequency differences across six loci allowed the identification of population structures. Genetic differentiation in the same vineyard in consecutive years was of the same order of magnitude as the differences verified among the different vineyards. Correlation of genetic differentiation with the distance between sampling points within a vineyard suggested a pattern of isolation-by-distance, where genetic divergence in a vineyard increased with size. The continuous use of commercial yeasts has a limited influence on the autochthonous fermentative yeast population collected from grapes and may just slightly change populational structures of strains isolated from sites very close to the winery where they have been used. The present work is the first large-scale approach using microsatellite typing allowing a very fine resolution of indigenous S. cerevisiae populations isolated from vineyards.

The Mobilisatsia experience

International Nuclear Information System (INIS)

De Boever, P.

2005-01-01

The hazards of long-duration manned space flight are real. In order to participate effectively in long duration orbital missions or to continue the exploration of space, the health of the astronaut must be secured. There is mounting evidence that changes in the immune response of an astronaut in short-term flights, resemble those occurring after acute stress, while the changes during long-term flights resemble those caused by chronic stress. This blunting of the immune system occurs concomitant with a relative increase in microbial contamination in the space cabin environment. Such a combination of events results in an increased probability of in-flight infectious events. Micro-organisms are subject to a genetic evolution, which may lead to the capacity to colonize new environments and to cause infections. Central players in this evolutionary process are mobile genetic elements. They help to mobilize and reorganize genes, be it within a given genome (intragenomic mobility) or between bacterial cells (intercellular mobility). Hence, the processes of genetic exchange can mobilize genetic elements between bacterial strains, and therefore play a role in determining the infectious potential. The specific confined environment and space-flight related factors (such as microgravity and cosmic radiation) may increase the frequency in which mobile genetic elements are exchanged between micro organisms. The aim of the Mobilisatsia experiment was to promote microbial gene transfer under space flight conditions during a short-term experiment conducted aboard the International Space Station (ISS). The efficiency of the gene exchange process was compared with a synchronously performed ground control experiment. An experiment was carried out with well-characterized Gram-negative reference strains and one experiment was done with Gram-positive reference strains

Sensitivity to cocaine in adult mice is due to interplay between genetic makeup, early environment and later experience.

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Di Segni, Matteo; Andolina, Diego; Coassin, Alessandra; Accoto, Alessandra; Luchetti, Alessandra; Pascucci, Tiziana; Luzi, Carla; Lizzi, Anna Rita; D'Amato, Francesca R; Ventura, Rossella

2017-10-01

Although early aversive postnatal events are known to increase the risk to develop psychiatric disorders later in life, rarely they determine alone the nature and outcome of the psychopathology, indicating that interaction with genetic factors is crucial for expression of psychopathologies in adulthood. Moreover, it has been suggested that early life experiences could have negative consequences or confer adaptive value in different individuals. Here we suggest that resilience or vulnerability to adult cocaine sensitivity depends on a "triple interaction" between genetic makeup x early environment x later experience. We have recently showed that Repeated Cross Fostering (RCF; RCF pups were fostered by four adoptive mothers from postnatal day 1 to postnatal day 4. Pups were left with the last adoptive mother until weaning) experienced by pups affected the response to a negative experience in adulthood in opposite direction in two genotypes leading DBA2/J, but not C57BL/6J mice, toward an "anhedonia-like" phenotype. Here we investigate whether exposure to a rewarding stimulus, instead of a negative one, in adulthood induces an opposite behavioral outcome. To test this hypothesis, we investigated the long-lasting effects of RCF on cocaine sensitivity in C57 and DBA female mice by evaluating conditioned place preference induced by different cocaine doses and catecholamine prefrontal-accumbal response to cocaine using a "dual probe" in vivo microdialysis procedure. Moreover, cocaine-induced c-Fos activity was assessed in different brain regions involved in processing of rewarding stimuli. Finally, cocaine-induced spine changes were evaluated in the prefrontal-accumbal system. RCF experience strongly affected the behavioral, neurochemical and morphological responses to cocaine in adulthood in opposite direction in the two genotypes increasing and reducing, respectively, the sensitivity to cocaine in C57 and DBA mice. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ancient DNA reveals genetic connections between early Di-Qiang and Han Chinese.

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Li, Jiawei; Zeng, Wen; Zhang, Ye; Ko, Albert Min-Shan; Li, Chunxiang; Zhu, Hong; Fu, Qiaomei; Zhou, Hui

2017-12-04

Ancient Di-Qiang people once resided in the Ganqing region of China, adjacent to the Central Plain area from where Han Chinese originated. While gene flow between the Di-Qiang and Han Chinese has been proposed, there is no evidence to support this view. Here we analyzed the human remains from an early Di-Qiang site (Mogou site dated ~4000 years old) and compared them to other ancient DNA across China, including an early Han-related site (Hengbei site dated ~3000 years old) to establish the underlying genetic relationship between the Di-Qiang and ancestors of Han Chinese. We found Mogou mtDNA haplogroups were highly diverse, comprising 14 haplogroups: A, B, C, D (D*, D4, D5), F, G, M7, M8, M10, M13, M25, N*, N9a, and Z. In contrast, Mogou males were all Y-DNA haplogroup O3a2/P201; specifically one male was further assigned to O3a2c1a/M117 using targeted unique regions on the non-recombining region of the Y-chromosome. We compared Mogou to 7 other ancient and 38 modern Chinese groups, in a total of 1793 individuals, and found that Mogou shared close genetic distances with Taojiazhai (a more recent Di-Qiang population), Hengbei, and Northern Han. We modeled their interactions using Approximate Bayesian Computation, and support was given to a potential admixture of ~13-18% between the Mogou and Northern Han around 3300-3800 years ago. Mogou harbors the earliest genetically identifiable Di-Qiang, ancestral to the Taojiazhai, and up to ~33% paternal and ~70% of its maternal haplogroups could be found in present-day Northern Han Chinese.

A high degree of genetic diversity is revealed in Isatis spp. (dyer's woad) by amplified fragment length polymorphism (AFLP).

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Gilbert (nee Stoker), G.; Garton, S.; Karam, A.; Arnold, M.; Karp, A.; Edwards, J.; Cooke, T.; Barker, A.

2002-05-01

Genetic diversity in 38 genotypes, representing 28 individual genotypes from five landraces of Isatis tinctoria (three German: Tubingen, Potsdam and Erfurt, one Swiss and one English), five genotypes of Isatis indigotica (Chinese woad) and five genotypes of Isatis glauca, were investigated using AFLP analysis. Five primer combinations detected a total of 502 fragments of which 436 (86.9%) were polymorphic. The level of polymorphism recorded within each species was 29.8, 86.9 and 35.8% for I. indigotica, I. tinctoria and I. glauca, respectively. Clearly, genetic diversity within I. tinctoria was greater than that observed in I. indigotica or I. glauca. Cluster analyses of the AFLP data using UPGMA and PCO revealed the complete separation of the genotypes of each species into distinct groups. I. indigotica separated as an entirely independent group, whereas I. glauca formed a separate cluster within the I. tinctoria group. Indeed, I. tinctoria and I. glauca are more closely related to each other than either is to I. indigotica. In addition, the genotypes of each landrace, apart from one from the English group, were clearly discriminated. However, the anomalous genotype did associate with the rest of its group when it was linked with the Erfurt group. These results provide new and useful information about the make-up of the Isatis genome, which has not previously been evaluated. They will be useful in the selection of plant material for variety development and conservation of the gene-pool.

A rangewide population genetic study of trumpeter swans

Science.gov (United States)

Oyler-McCance, S.J.; Ransler, F.A.; Berkman, L.K.; Quinn, T.W.

2007-01-01

For management purposes, the range of naturally occurring trumpeter swans (Cygnus buccinator) has been divided into two populations, the Pacific Coast Population (PP) and the Rocky Mountain Population (RMP). Little is known about the distribution of genetic variation across the species' range despite increasing pressure to make difficult management decisions regarding the two populations and flocks within them. To address this issue, we used rapidly evolving genetic markers (mitochondrial DNA sequence and 17 nuclear microsatellite loci) to elucidate the underlying genetic structure of the species. Data from both markers revealed a significant difference between the PP and RMP with the Yukon Territory as a likely area of overlap. Additionally, we found that the two populations have somewhat similar levels of genetic diversity (PP is slightly higher) suggesting that the PP underwent a population bottleneck similar to a well-documented one in the RMP. Both genetic structure and diversity results reveal that the Tri-State flock, a suspected unique, non-migratory flock, is not genetically different from the Canadian flock of the RMP and need not be treated as a unique population from a genetic standpoint. Finally, trumpeter swans appear to have much lower mitochondrial DNA variability than other waterfowl studied thus far which may suggest a previous, species-wide bottleneck. ?? 2007 Springer Science+Business Media, Inc.

Imaging Voltage in Genetically Defined Neuronal Subpopulations with a Cre Recombinase-Targeted Hybrid Voltage Sensor.

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Bayguinov, Peter O; Ma, Yihe; Gao, Yu; Zhao, Xinyu; Jackson, Meyer B

2017-09-20

Genetically encoded voltage indicators create an opportunity to monitor electrical activity in defined sets of neurons as they participate in the complex patterns of coordinated electrical activity that underlie nervous system function. Taking full advantage of genetically encoded voltage indicators requires a generalized strategy for targeting the probe to genetically defined populations of cells. To this end, we have generated a mouse line with an optimized hybrid voltage sensor (hVOS) probe within a locus designed for efficient Cre recombinase-dependent expression. Crossing this mouse with Cre drivers generated double transgenics expressing hVOS probe in GABAergic, parvalbumin, and calretinin interneurons, as well as hilar mossy cells, new adult-born neurons, and recently active neurons. In each case, imaging in brain slices from male or female animals revealed electrically evoked optical signals from multiple individual neurons in single trials. These imaging experiments revealed action potentials, dynamic aspects of dendritic integration, and trial-to-trial fluctuations in response latency. The rapid time response of hVOS imaging revealed action potentials with high temporal fidelity, and enabled accurate measurements of spike half-widths characteristic of each cell type. Simultaneous recording of rapid voltage changes in multiple neurons with a common genetic signature offers a powerful approach to the study of neural circuit function and the investigation of how neural networks encode, process, and store information. SIGNIFICANCE STATEMENT Genetically encoded voltage indicators hold great promise in the study of neural circuitry, but realizing their full potential depends on targeting the sensor to distinct cell types. Here we present a new mouse line that expresses a hybrid optical voltage sensor under the control of Cre recombinase. Crossing this line with Cre drivers generated double-transgenic mice, which express this sensor in targeted cell types. In

Genetics of the pig tapeworm in madagascar reveal a history of human dispersal and colonization.

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Yanagida, Tetsuya; Carod, Jean-François; Sako, Yasuhito; Nakao, Minoru; Hoberg, Eric P; Ito, Akira

2014-01-01

An intricate history of human dispersal and geographic colonization has strongly affected the distribution of human pathogens. The pig tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serious neglected tropical diseases. Discrete genetic lineages of T. solium in Asia and Africa/Latin America are geographically disjunct; only in Madagascar are they sympatric. Linguistic, archaeological and genetic evidence has indicated that the people in Madagascar have mixed ancestry from Island Southeast Asia and East Africa. Hence, anthropogenic introduction of the tapeworm from Southeast Asia and Africa had been postulated. This study shows that the major mitochondrial haplotype of T. solium in Madagascar is closely related to those from the Indian Subcontinent. Parasitological evidence presented here, and human genetics previously reported, support the hypothesis of an Indian influence on Malagasy culture coinciding with periods of early human migration onto the island. We also found evidence of nuclear-mitochondrial discordance in single tapeworms, indicating unexpected cross-fertilization between the two lineages of T. solium. Analyses of genetic and geographic populations of T. solium in Madagascar will shed light on apparently rapid evolution of this organism driven by recent (<2,000 yr) human migrations, following tens of thousands of years of geographic isolation.

Does genetic diversity hinder parasite evolution in social insect colonies?

DEFF Research Database (Denmark)

Hughes, William Owen Hamar; Boomsma, Jacobus Jan

2006-01-01

of host genetic diversity on parasite evolution by carrying out serial passages of a virulent fungal pathogen through leaf-cutting ant workers of known genotypes. Parasite virulence increased over the nine-generation span of the experiment while spore production decreased. The effect of host relatedness...... upon virulence appeared limited. However, parasites cycled through more genetically diverse hosts were more likely to go extinct during the experiment and parasites cycled through more genetically similar hosts had greater spore production. These results indicate that host genetic diversity may indeed...

High-density SNP genotyping of tomato (Solanum lycopersicum L. reveals patterns of genetic variation due to breeding.

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Sung-Chur Sim

Full Text Available The effects of selection on genome variation were investigated and visualized in tomato using a high-density single nucleotide polymorphism (SNP array. 7,720 SNPs were genotyped on a collection of 426 tomato accessions (410 inbreds and 16 hybrids and over 97% of the markers were polymorphic in the entire collection. Principal component analysis (PCA and pairwise estimates of F(st supported that the inbred accessions represented seven sub-populations including processing, large-fruited fresh market, large-fruited vintage, cultivated cherry, landrace, wild cherry, and S. pimpinellifolium. Further divisions were found within both the contemporary processing and fresh market sub-populations. These sub-populations showed higher levels of genetic diversity relative to the vintage sub-population. The array provided a large number of polymorphic SNP markers across each sub-population, ranging from 3,159 in the vintage accessions to 6,234 in the cultivated cherry accessions. Visualization of minor allele frequency revealed regions of the genome that distinguished three representative sub-populations of cultivated tomato (processing, fresh market, and vintage, particularly on chromosomes 2, 4, 5, 6, and 11. The PCA loadings and F(st outlier analysis between these three sub-populations identified a large number of candidate loci under positive selection on chromosomes 4, 5, and 11. The extent of linkage disequilibrium (LD was examined within each chromosome for these sub-populations. LD decay varied between chromosomes and sub-populations, with large differences reflective of breeding history. For example, on chromosome 11, decay occurred over 0.8 cM for processing accessions and over 19.7 cM for fresh market accessions. The observed SNP variation and LD decay suggest that different patterns of genetic variation in cultivated tomato are due to introgression from wild species and selection for market specialization.

Species delimitation in lemurs: multiple genetic loci reveal low levels of species diversity in the genus Cheirogaleus

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Rasoloarison Rodin M

2009-02-01

Full Text Available Abstract Background Species are viewed as the fundamental unit in most subdisciplines of biology. To conservationists this unit represents the currency for global biodiversity assessments. Even though Madagascar belongs to one of the top eight biodiversity hotspots of the world, the taxonomy of its charismatic lemuriform primates is not stable. Within the last 25 years, the number of described lemur species has more than doubled, with many newly described species identified among the nocturnal and small-bodied cheirogaleids. Here, we characterize the diversity of the dwarf lemurs (genus Cheirogaleus and assess the status of the seven described species, based on phylogenetic and population genetic analysis of mtDNA (cytb + cox2 and three nuclear markers (adora3, fiba and vWF. Results This study identified three distinct evolutionary lineages within the genus Cheirogaleus. Population genetic cluster analyses revealed a further layer of population divergence with six distinct genotypic clusters. Conclusion Based on the general metapopulation lineage concept and multiple concordant data sets, we identify three exclusive groups of dwarf lemur populations that correspond to three of the seven named species: C. major, C. medius and C. crossleyi. These three species were found to be genealogically exclusive in both mtDNA and nDNA loci and are morphologically distinguishable. The molecular and morphometric data indicate that C. adipicaudatus and C. ravus are synonymous with C. medius and C. major, respectively. Cheirogaleus sibreei falls into the C. medius mtDNA clade, but in morphological analyses the membership is not clearly resolved. We do not have sufficient data to assess the status of C. minusculus. Although additional patterns of population differentiation are evident, there are no clear subdivisions that would warrant additional specific status. We propose that ecological and more geographic data should be collected to confirm these results.

Childhood Abuse Experiences and the COMT and MTHFR Genetic Variants Associated With Male Sexual Orientation in the Han Chinese Populations: A Case-Control Study.

Science.gov (United States)

Qin, Jia-Bi; Zhao, Guang-Lu; Wang, Feng; Cai, Yu-Mao; Lan, Li-Na; Yang, Lin; Feng, Tie-Jian

2018-01-01

Although it is widely acknowledged that genetic and environmental factors are involved in the development of male homosexuality, the causes are not fully understood. To explore the association and interaction of childhood abuse experiences and genetic variants of the catechol-O-methyltransferase (COMT) and methylenetetrahydrofolate reductase (MTHFR) genes with the development of male homosexuality. A case-control study of 537 exclusively homosexual men and 583 exclusively heterosexual men was conducted, with data collected from March 2013 to August 2015. Data were analyzed using χ 2 tests and logistic regression models. Sociodemographic characteristics, childhood abuse experiences, and polymorphisms of COMT at rs4680, rs4818, and rs6267 and MTHFR at rs1801133. More frequent occurrence of physical (adjusted odds ratio [aOR] = 1.78), emotional (aOR = 2.07), and sexual (aOR = 2.53) abuse during childhood was significantly associated with the development of male homosexuality. The polymorphisms of MTHFR at rs1801133 and COMT at rs4818 also were significantly associated with the development of male homosexuality in the homozygote comparisons (T/T vs C/C at rs1801133, aOR = 1.68; G/G vs C/C at rs4818, aOR = 1.75). In addition, significant interaction effects between childhood abuse experiences and the COMT and MTHFR genetic variants on the development of male homosexuality were found. This is the first time that an association of childhood abuse, COMT and MTHFR genetic variants, and their interactions with development of male homosexuality was exhaustively explored, which could help provide new insight into the etiology of male homosexuality. Because homosexual men are a relatively obscure population, it was impossible to select the study participants by random sampling, which could lead to selection bias. In addition, because this was a case-control study, recall bias was inevitable, and we could not verify causality. Childhood abuse and the COMT and MTHFR genetic

Randomly detected genetically modified (GM maize (Zea mays L. near a transport route revealed a fragile 45S rDNA phenotype.

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Nomar Espinosa Waminal

Full Text Available Monitoring of genetically modified (GM crops has been emphasized to prevent their potential effects on the environment and human health. Monitoring of the inadvertent dispersal of transgenic maize in several fields and transport routes in Korea was carried out by qualitative multiplex PCR, and molecular analyses were conducted to identify the events of the collected GM maize. Cytogenetic investigations through fluorescence in situ hybridization (FISH of the GM maize were performed to check for possible changes in the 45S rDNA cluster because this cluster was reported to be sensitive to replication and transcription stress. Three GM maize kernels were collected from a transport route near Incheon port, Korea, and each was found to contain NK603, stacked MON863 x NK603, and stacked NK603 x MON810 inserts, respectively. Cytogenetic analysis of the GM maize containing the stacked NK603 x MON810 insert revealed two normal compact 5S rDNA signals, but the 45S rDNA showed a fragile phenotype, demonstrating a "beads-on-a-string" fragmentation pattern, which seems to be a consequence of genetic modification. Implications of the 45S rDNA cluster fragility in GM maize are also discussed.

Genetic analysis of the isolated Faroe Islands reveals SORCS3 as a potential multiple sclerosis risk gene

DEFF Research Database (Denmark)

Binzer, Stefanie; Stenager, Egon; Binzer, Michael

2016-01-01

BACKGROUND: In search of the missing heritability in multiple sclerosis (MS), additional approaches adding to the genetic discoveries of large genome-wide association studies are warranted. OBJECTIVE: The objective of this research paper is to search for rare genetic MS risk variants...... in the genetically homogenous population of the isolated Faroe Islands. METHODS: Twenty-nine Faroese MS cases and 28 controls were genotyped with the HumanOmniExpressExome-chip. The individuals make up 1596 pair-combinations in which we searched for identical-by-descent shared segments using the PLINK...... of neurotrophin factors and involvement in glutamate homeostasis. Although additional work is needed to scrutinise the genetic effect of the SORCS3-covering haplotype, this study suggests that SORCS3 may also be important in MS pathogenesis....

Genetic differentiation of watermelon landrace types in Mali revealed by microsatellite (SSR) markers

DEFF Research Database (Denmark)

Nantoume, Aminata Dolo; Andersen, Sven Bode; Jensen, Brita Dahl

2013-01-01

This study describes the genetic differentiation of a collection of 134 watermelon landrace accessions from Mali, representing red fleshed dessert and white fleshed seed and cooking type watermelons from five regions, plus three commercial dessert type cultivars with red flesh. The material...... the accessions into use groups (dessert, cooking, seed processing) explained 25 % of the variation. When categorising the accessions further into 10 landrace types, differentiated on the basis of use groups, local accession name, flesh colour and seed phenotype, these landrace types explained 26......-groups. One group included again the red fleshed dessert types with local and commercial origin, while the remaining seven genetic sub-groups comprised the white fleshed landrace types used for seed processing and cooking, as well as white fleshed types of one dessert type. Some of the seed and cooking types...

Mammalian developmental genetics in the twentieth century.

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Artzt, Karen

2012-12-01

This Perspectives is a review of the breathtaking history of mammalian genetics in the past century and, in particular, of the ways in which genetic thinking has illuminated aspects of mouse development. To illustrate the power of that thinking, selected hypothesis-driven experiments and technical advances are discussed. Also included in this account are the beginnings of mouse genetics at the Bussey Institute, Columbia University, and The Jackson Laboratory and a retrospective discussion of one of the classic problems in developmental genetics, the T/t complex and its genetic enigmas.

Genetic diversity assessed by microsatellite markers in sweet corn cultivars

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Ana Daniela Lopes

2015-12-01

Full Text Available Information on genetic diversity is essential to the characterization and utilization of germplasm. The genetic diversity of twenty-two sweet corn cultivars (seventeen open-pollinated varieties, OPV, and five hybrids, H was investigated by applying simple sequence repeat markers. A total of 257 primers were tested, of which 160 were found to be usable in terms of high reproducibility for all the samples tested; 45 were polymorphic loci, of which 30 were used to assess the genetic diversity of sweet corn cultivars. We detected a total of 86 alleles using 30 microsatellite primers. The mean polymorphism was 82 %. The highest heterozygosity values (Ho = 0.20 were found in the PR030-Doce Flor da Serra and BR427 III OPVs, whereas the lowest values (0.14 were recorded in the MG161-Branco Doce and Doce Cubano OPVs. The polymorphism information content ranged from 0.19 (Umc2319 to 0.71 (Umc2205. The analysis of molecular variance revealed that most of the genetic variability was concentrated within the cultivars of sweet corn (75 %, with less variability between them (25 %. The consensus tree derived from the neighbor-joining (NJ algorithm using 1,000 bootstrapping replicates revealed seven genetically different groups. Nei’s diversity values varied between 0.103 (Doce do Hawai × CNPH-1 cultivars and 0.645 (Amarelo Doce × Lili cultivars, indicating a narrow genetic basis. The Lili hybrid was the most distant cultivar, as revealed by Principal Coordinates Analysis and the NJ tree. This study on genetic diversity will be useful for planning future studies on sweet corn genetic resources and can complement the breeding programs for this crop.

Reproductive isolation revealed in preliminary crossbreeding experiments using field collected Triatoma dimidiata (Hemiptera: Reduviidae) from three ITS–2 defined groups

OpenAIRE

García, Mauricio; Menes, Marianela; Dorn, Patricia L.; Monroy, Carlota; Richards, Bethany; Panzera, Francisco; Bustamante, Dulce María

2013-01-01

Triatoma dimidiata, a Chagas disease vector distributed in Mexico, Central America, Colombia, Venezuela, Peru and Ecuador, has been studied using genetic markers and four groups have been defined by ITS–2 sequences: 1A, 1B, 2 and 3. To gather evidence on the divergence and reproductive isolation among T. dimidiata ITS–2 groups, we carried out 15 crossbreeding experiments with field–collected sylvan and domestic T. dimidiata from Guatemala where three groups are found: 1A, 2 and 3. Reciprocal ...

Genetic and environmental influences on the relationship between flow proneness, locus of control and behavioral inhibition.

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Miriam A Mosing

Full Text Available Flow is a psychological state of high but subjectively effortless attention that typically occurs during active performance of challenging tasks and is accompanied by a sense of automaticity, high control, low self-awareness, and enjoyment. Flow proneness is associated with traits and behaviors related to low neuroticism such as emotional stability, conscientiousness, active coping, self-esteem and life satisfaction. Little is known about the genetic architecture of flow proneness, behavioral inhibition and locus of control--traits also associated with neuroticism--and their interrelation. Here, we hypothesized that individuals low in behavioral inhibition and with an internal locus of control would be more likely to experience flow and explored the genetic and environmental architecture of the relationship between the three variables. Behavioral inhibition and locus of control was measured in a large population sample of 3,375 full twin pairs and 4,527 single twins, about 26% of whom also scored the flow proneness questionnaire. Findings revealed significant but relatively low correlations between the three traits and moderate heritability estimates of .41, .45, and .30 for flow proneness, behavioral inhibition, and locus of control, respectively, with some indication of non-additive genetic influences. For behavioral inhibition we found significant sex differences in heritability, with females showing a higher estimate including significant non-additive genetic influences, while in males the entire heritability was due to additive genetic variance. We also found a mainly genetically mediated relationship between the three traits, suggesting that individuals who are genetically predisposed to experience flow, show less behavioral inhibition (less anxious and feel that they are in control of their own destiny (internal locus of control. We discuss that some of the genes underlying this relationship may include those influencing the function of

Genetic and environmental influences on the relationship between flow proneness, locus of control and behavioral inhibition.

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Mosing, Miriam A; Pedersen, Nancy L; Cesarini, David; Johannesson, Magnus; Magnusson, Patrik K E; Nakamura, Jeanne; Madison, Guy; Ullén, Fredrik

2012-01-01

Flow is a psychological state of high but subjectively effortless attention that typically occurs during active performance of challenging tasks and is accompanied by a sense of automaticity, high control, low self-awareness, and enjoyment. Flow proneness is associated with traits and behaviors related to low neuroticism such as emotional stability, conscientiousness, active coping, self-esteem and life satisfaction. Little is known about the genetic architecture of flow proneness, behavioral inhibition and locus of control--traits also associated with neuroticism--and their interrelation. Here, we hypothesized that individuals low in behavioral inhibition and with an internal locus of control would be more likely to experience flow and explored the genetic and environmental architecture of the relationship between the three variables. Behavioral inhibition and locus of control was measured in a large population sample of 3,375 full twin pairs and 4,527 single twins, about 26% of whom also scored the flow proneness questionnaire. Findings revealed significant but relatively low correlations between the three traits and moderate heritability estimates of .41, .45, and .30 for flow proneness, behavioral inhibition, and locus of control, respectively, with some indication of non-additive genetic influences. For behavioral inhibition we found significant sex differences in heritability, with females showing a higher estimate including significant non-additive genetic influences, while in males the entire heritability was due to additive genetic variance. We also found a mainly genetically mediated relationship between the three traits, suggesting that individuals who are genetically predisposed to experience flow, show less behavioral inhibition (less anxious) and feel that they are in control of their own destiny (internal locus of control). We discuss that some of the genes underlying this relationship may include those influencing the function of dopaminergic neural

Surveys suck: Consumer preferences when purchasing genetically engineered foods.

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Powell, Douglas A

2013-01-01

Many studies have attempted to gauge consumers' acceptance of genetically engineered or modified (GM) foods. Surveys, asking people about attitudes and intentions, are easy-to-collect proxies of consumer behavior. However, participants tend to respond as citizens of society, not discrete individuals, thereby inaccurately portraying their potential behavior. The Theory of Planned Behavior improved the accuracy of self-reported information, but its limited capacity to account for intention variance has been attributed to the hypothetical scenarios to which survey participants must respond. Valuation methods, asking how much consumers may be willing to pay or accept for GM foods, have revealed that consumers are usually willing to accept them at some price, or in some cases willing to pay a premium. Ultimately, it's consumers' actual--not intended--behavior that is of most interest to policy makers and business decision-makers. Real choice experiments offer the best avenue for revealing consumers' food choices in normal life.

Mapping DNA damage-dependent genetic interactions in yeast via party mating and barcode fusion genetics.

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Díaz-Mejía, J Javier; Celaj, Albi; Mellor, Joseph C; Coté, Atina; Balint, Attila; Ho, Brandon; Bansal, Pritpal; Shaeri, Fatemeh; Gebbia, Marinella; Weile, Jochen; Verby, Marta; Karkhanina, Anna; Zhang, YiFan; Wong, Cassandra; Rich, Justin; Prendergast, D'Arcy; Gupta, Gaurav; Öztürk, Sedide; Durocher, Daniel; Brown, Grant W; Roth, Frederick P

2018-05-28

Condition-dependent genetic interactions can reveal functional relationships between genes that are not evident under standard culture conditions. State-of-the-art yeast genetic interaction mapping, which relies on robotic manipulation of arrays of double-mutant strains, does not scale readily to multi-condition studies. Here, we describe barcode fusion genetics to map genetic interactions (BFG-GI), by which double-mutant strains generated via en masse "party" mating can also be monitored en masse for growth to detect genetic interactions. By using site-specific recombination to fuse two DNA barcodes, each representing a specific gene deletion, BFG-GI enables multiplexed quantitative tracking of double mutants via next-generation sequencing. We applied BFG-GI to a matrix of DNA repair genes under nine different conditions, including methyl methanesulfonate (MMS), 4-nitroquinoline 1-oxide (4NQO), bleomycin, zeocin, and three other DNA-damaging environments. BFG-GI recapitulated known genetic interactions and yielded new condition-dependent genetic interactions. We validated and further explored a subnetwork of condition-dependent genetic interactions involving MAG1 , SLX4, and genes encoding the Shu complex, and inferred that loss of the Shu complex leads to an increase in the activation of the checkpoint protein kinase Rad53. © 2018 The Authors. Published under the terms of the CC BY 4.0 license.

Population genetics of two key mosquito vectors of Rift Valley Fever virus reveals new insights into the changing disease outbreak patterns in Kenya.

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David P Tchouassi

2014-12-01

Full Text Available Rift Valley fever (RVF outbreaks in Kenya have increased in frequency and range to include northeastern Kenya where viruses are increasingly being isolated from known (Aedes mcintoshi and newly-associated (Ae. ochraceus vectors. The factors contributing to these changing outbreak patterns are unclear and the population genetic structure of key vectors and/or specific virus-vector associations, in particular, are under-studied. By conducting mitochondrial and nuclear DNA analyses on >220 Kenyan specimens of Ae. mcintoshi and Ae. ochraceus, we uncovered high levels of vector complexity which may partly explain the disease outbreak pattern. Results indicate that Ae. mcintoshi consists of a species complex with one of the member species being unique to the newly-established RVF outbreak-prone northeastern region of Kenya, whereas Ae. ochraceus is a homogeneous population that appears to be undergoing expansion. Characterization of specimens from a RVF-prone site in Senegal, where Ae. ochraceus is a primary vector, revealed direct genetic links between the two Ae. ochraceus populations from both countries. Our data strongly suggest that unlike Ae. mcintoshi, Ae. ochraceus appears to be a relatively recent, single 'introduction' into Kenya. These results, together with increasing isolations from this vector, indicate that Ae. ochraceus will likely be of greater epidemiological importance in future RVF outbreaks in Kenya. Furthermore, the overall vector complexity calls into question the feasibility of mosquito population control approaches reliant on genetic modification.

Population Genetics of Two Key Mosquito Vectors of Rift Valley Fever Virus Reveals New Insights into the Changing Disease Outbreak Patterns in Kenya

Science.gov (United States)

Tchouassi, David P.; Bastos, Armanda D. S.; Sole, Catherine L.; Diallo, Mawlouth; Lutomiah, Joel; Mutisya, James; Mulwa, Francis; Borgemeister, Christian; Sang, Rosemary; Torto, Baldwyn

2014-01-01

Rift Valley fever (RVF) outbreaks in Kenya have increased in frequency and range to include northeastern Kenya where viruses are increasingly being isolated from known (Aedes mcintoshi) and newly-associated (Ae. ochraceus) vectors. The factors contributing to these changing outbreak patterns are unclear and the population genetic structure of key vectors and/or specific virus-vector associations, in particular, are under-studied. By conducting mitochondrial and nuclear DNA analyses on >220 Kenyan specimens of Ae. mcintoshi and Ae. ochraceus, we uncovered high levels of vector complexity which may partly explain the disease outbreak pattern. Results indicate that Ae. mcintoshi consists of a species complex with one of the member species being unique to the newly-established RVF outbreak-prone northeastern region of Kenya, whereas Ae. ochraceus is a homogeneous population that appears to be undergoing expansion. Characterization of specimens from a RVF-prone site in Senegal, where Ae. ochraceus is a primary vector, revealed direct genetic links between the two Ae. ochraceus populations from both countries. Our data strongly suggest that unlike Ae. mcintoshi, Ae. ochraceus appears to be a relatively recent, single 'introduction' into Kenya. These results, together with increasing isolations from this vector, indicate that Ae. ochraceus will likely be of greater epidemiological importance in future RVF outbreaks in Kenya. Furthermore, the overall vector complexity calls into question the feasibility of mosquito population control approaches reliant on genetic modification. PMID:25474018

Whole exome sequencing in 342 congenital cardiac left sided lesion cases reveals extensive genetic heterogeneity and complex inheritance patterns

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Alexander H. Li

2017-10-01

Full Text Available Abstract Background Left-sided lesions (LSLs account for an important fraction of severe congenital cardiovascular malformations (CVMs. The genetic contributions to LSLs are complex, and the mutations that cause these malformations span several diverse biological signaling pathways: TGFB, NOTCH, SHH, and more. Here, we use whole exome sequence data generated in 342 LSL cases to identify likely damaging variants in putative candidate CVM genes. Methods Using a series of bioinformatics filters, we focused on genes harboring population-rare, putative loss-of-function (LOF, and predicted damaging variants in 1760 CVM candidate genes constructed a priori from the literature and model organism databases. Gene variants that were not observed in a comparably sequenced control dataset of 5492 samples without severe CVM were then subjected to targeted validation in cases and parents. Whole exome sequencing data from 4593 individuals referred for clinical sequencing were used to bolster evidence for the role of candidate genes in CVMs and LSLs. Results Our analyses revealed 28 candidate variants in 27 genes, including 17 genes not previously associated with a human CVM disorder, and revealed diverse patterns of inheritance among LOF carriers, including 9 confirmed de novo variants in both novel and newly described human CVM candidate genes (ACVR1, JARID2, NR2F2, PLRG1, SMURF1 as well as established syndromic CVM genes (KMT2D, NF1, TBX20, ZEB2. We also identified two genes (DNAH5, OFD1 with evidence of recessive and hemizygous inheritance patterns, respectively. Within our clinical cohort, we also observed heterozygous LOF variants in JARID2 and SMAD1 in individuals with cardiac phenotypes, and collectively, carriers of LOF variants in our candidate genes had a four times higher odds of having CVM (odds ratio = 4.0, 95% confidence interval 2.5–6.5. Conclusions Our analytical strategy highlights the utility of bioinformatic resources, including human

Genetically encoded proton sensors reveal activity-dependent pH changes in neurons

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Joseph Valentino Raimondo

2012-05-01

Full Text Available The regulation of hydrogen ion concentration (pH is fundamental to cell viability, metabolism and enzymatic function. Within the nervous system, the control of pH is also involved in diverse and dynamic processes including development, synaptic transmission and the control of network excitability. As pH affects neuronal activity, and can also itself be altered by neuronal activity, the existence of tools to accurately measure hydrogen ion fluctuations is important for understanding the role pH plays under physiological and pathological conditions. Outside of their use as a marker of synaptic release, genetically encoded pH sensors have not been utilised to study hydrogen ion fluxes associated with network activity. By combining whole-cell patch clamp with simultaneous two-photon or confocal imaging, we quantified the amplitude and time course of neuronal, intracellular, acidic transients evoked by epileptiform activity in two separate in vitro models of temporal lobe epilepsy. In doing so, we demonstrate the suitability of three genetically encoded pH sensors: deGFP4, E2GFP and Cl-sensor for investigating activity-dependent pH changes at the level of single neurons.

Genetically encoded proton sensors reveal activity-dependent pH changes in neurons.

Science.gov (United States)

Raimondo, Joseph V; Irkle, Agnese; Wefelmeyer, Winnie; Newey, Sarah E; Akerman, Colin J

2012-01-01

The regulation of hydrogen ion concentration (pH) is fundamental to cell viability, metabolism, and enzymatic function. Within the nervous system, the control of pH is also involved in diverse and dynamic processes including development, synaptic transmission, and the control of network excitability. As pH affects neuronal activity, and can also itself be altered by neuronal activity, the existence of tools to accurately measure hydrogen ion fluctuations is important for understanding the role pH plays under physiological and pathological conditions. Outside of their use as a marker of synaptic release, genetically encoded pH sensors have not been utilized to study hydrogen ion fluxes associated with network activity. By combining whole-cell patch clamp with simultaneous two-photon or confocal imaging, we quantified the amplitude and time course of neuronal, intracellular, acidic transients evoked by epileptiform activity in two separate in vitro models of temporal lobe epilepsy. In doing so, we demonstrate the suitability of three genetically encoded pH sensors: deGFP4, E(2)GFP, and Cl-sensor for investigating activity-dependent pH changes at the level of single neurons.

Genetic analysis reveals demographic fragmentation of grizzly bears yielding vulnerably small populations.

Science.gov (United States)

Proctor, Michael F; McLellan, Bruce N; Strobeck, Curtis; Barclay, Robert M R

2005-11-22

Ecosystem conservation requires the presence of native carnivores, yet in North America, the distributions of many larger carnivores have contracted. Large carnivores live at low densities and require large areas to thrive at the population level. Therefore, if human-dominated landscapes fragment remaining carnivore populations, small and demographically vulnerable populations may result. Grizzly bear range contraction in the conterminous USA has left four fragmented populations, three of which remain along the Canada-USA border. A tenet of grizzly bear conservation is that the viability of these populations requires demographic linkage (i.e. inter-population movement of both sexes) to Canadian bears. Using individual-based genetic analysis, our results suggest this demographic connection has been severed across their entire range in southern Canada by a highway and associated settlements, limiting female and reducing male movement. Two resulting populations are vulnerably small (bear populations may be more threatened than previously thought and that conservation efforts must expand to include international connectivity management. They also demonstrate the ability of genetic analysis to detect gender-specific demographic population fragmentation in recently disturbed systems, a traditionally intractable yet increasingly important ecological measurement worldwide.

Evolutionary Meta-Analysis of Association Studies Reveals Ancient Constraints Affecting Disease Marker Discovery

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Dudley, Joel T.; Chen, Rong; Sanderford, Maxwell; Butte, Atul J.; Kumar, Sudhir

2012-01-01

Genome-wide disease association studies contrast genetic variation between disease cohorts and healthy populations to discover single nucleotide polymorphisms (SNPs) and other genetic markers revealing underlying genetic architectures of human diseases. Despite scores of efforts over the past decade, many reproducible genetic variants that explain substantial proportions of the heritable risk of common human diseases remain undiscovered. We have conducted a multispecies genomic analysis of 5,831 putative human risk variants for more than 230 disease phenotypes reported in 2,021 studies. We find that the current approaches show a propensity for discovering disease-associated SNPs (dSNPs) at conserved genomic positions because the effect size (odds ratio) and allelic P value of genetic association of an SNP relates strongly to the evolutionary conservation of their genomic position. We propose a new measure for ranking SNPs that integrates evolutionary conservation scores and the P value (E-rank). Using published data from a large case-control study, we demonstrate that E-rank method prioritizes SNPs with a greater likelihood of bona fide and reproducible genetic disease associations, many of which may explain greater proportions of genetic variance. Therefore, long-term evolutionary histories of genomic positions offer key practical utility in reassessing data from existing disease association studies, and in the design and analysis of future studies aimed at revealing the genetic basis of common human diseases. PMID:22389448

African American women's limited knowledge and experiences with genetic counseling for hereditary breast cancer.

Science.gov (United States)

Sheppard, Vanessa B; Graves, Kristi D; Christopher, Juleen; Hurtado-de-Mendoza, Alejandra; Talley, Costellia; Williams, Karen Patricia

2014-06-01

Genetic counseling and testing for hereditary breast cancer have the potential benefit of early detection and early interventions in African American women. However, African American women have low use of these services compared to White women. We conducted two focus groups with African American women diagnosed with breast cancer (affected group, n = 13) and women with at least one first-degree relative with breast/ovarian cancer (unaffected group, n = 8). A content analysis approach was employed to analyze interview data. Breast cancer survivors had more knowledge about genetic counseling and testing than participants who were unaffected with cancer. However, knowledge about genetic counseling was limited in both groups. Barriers to pursuing genetic counseling and testing included poor understanding of the genetic counseling and testing process, fear of carrying the mutation, concerns about discrimination, and cost. Motivators to participate in genetic counseling and testing included desire to help family members, insurance coverage, and potential of benefiting the larger African American community. Education efforts are needed to increase genetic counseling and testing awareness in the African American community.

Prevalence and detection of psychosocial problems in cancer genetic counseling

NARCIS (Netherlands)

Eijzenga, W.; Bleiker, E.M.A.; Hahn, D.E.E.; van der Kolk, L.E.; Sidharta, G.N.; Aaronson, N.K.

2015-01-01

Only a minority of individuals who undergo cancer genetic counseling experience heightened levels of psychological distress, but many more experience a range of cancer genetic-specific psychosocial problems. The aim of this study was to estimate the prevalence of such psychosocial problems, and to

Genetic parameters and estimated genetic gains in young rubber tree progenies

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Cecília Khusala Verardi

2013-04-01

Full Text Available The objective of this work was to assess the genetic parameters and to estimate genetic gains in young rubber tree progenies. The experiments were carried out during three years, in a randomized block design, with six replicates and ten plants per plot, in three representative Hevea crop regions of the state of São Paulo, Brazil. Twenty-two progenies were evaluated, from three to five years old, for rubber yield and annual girth growth. Genetic gain was estimated with the multi-effect index (MEI. Selection by progenies means provided greater estimated genetic gain than selection based on individuals, since heritability values of progeny means were greater than the ones of individual heritability, for both evaluated variables, in all the assessment years. The selection of the three best progenies for rubber yield provided a selection gain of 1.28 g per plant. The genetic gains estimated with MEI using data from early assessments (from 3 to 5-year-old were generally high for annual girth growth and rubber yield. The high genetic gains for annual girth growth in the first year of assessment indicate that progenies can be selected at the beginning of the breeding program. Population effective size was consistent with the three progenies selected, showing that they were not related and that the population genetic variability is ensured. Early selection with the genetic gains estimated by MEI can be made on rubber tree progenies.

Chad Genetic Diversity Reveals an African History Marked by Multiple Holocene Eurasian Migrations.

Science.gov (United States)

Haber, Marc; Mezzavilla, Massimo; Bergström, Anders; Prado-Martinez, Javier; Hallast, Pille; Saif-Ali, Riyadh; Al-Habori, Molham; Dedoussis, George; Zeggini, Eleftheria; Blue-Smith, Jason; Wells, R Spencer; Xue, Yali; Zalloua, Pierre A; Tyler-Smith, Chris

2016-12-01

Understanding human genetic diversity in Africa is important for interpreting the evolution of all humans, yet vast regions in Africa, such as Chad, remain genetically poorly investigated. Here, we use genotype data from 480 samples from Chad, the Near East, and southern Europe, as well as whole-genome sequencing from 19 of them, to show that many populations today derive their genomes from ancient African-Eurasian admixtures. We found evidence of early Eurasian backflow to Africa in people speaking the unclassified isolate Laal language in southern Chad and estimate from linkage-disequilibrium decay that this occurred 4,750-7,200 years ago. It brought to Africa a Y chromosome lineage (R1b-V88) whose closest relatives are widespread in present-day Eurasia; we estimate from sequence data that the Chad R1b-V88 Y chromosomes coalesced 5,700-7,300 years ago. This migration could thus have originated among Near Eastern farmers during the African Humid Period. We also found that the previously documented Eurasian backflow into Africa, which occurred ∼3,000 years ago and was thought to be mostly limited to East Africa, had a more westward impact affecting populations in northern Chad, such as the Toubou, who have 20%-30% Eurasian ancestry today. We observed a decline in heterozygosity in admixed Africans and found that the Eurasian admixture can bias inferences on their coalescent history and confound genetic signals from adaptation and archaic introgression. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Genome-scale data reveal that endemic Poecilia populations from small sulphidic springs display no evidence of inbreeding.

Science.gov (United States)

Brown, Anthony P; Greenway, Ryan; Morgan, Samuel; Quackenbush, Corey R; Giordani, Luca; Arias-Rodriguez, Lenin; Tobler, Michael; Kelley, Joanna L

2017-10-01

Populations with limited ranges can be highly vulnerable to changes in their environment and are, thus, of high conservation concern. Populations that experience human-induced range reductions are often highly inbred and lack genetic diversity, but it is unknown whether this is also the case for populations with naturally small ranges. The fishes Poecilia sulphuraria (listed as critically endangered) and Poecilia thermalis, which are endemic to small hydrogen sulphide-rich springs in southern Mexico, are examples of such populations with inherently small habitats. We used geometric morphometrics and population genetics to quantify phenotypic and genetic variation within and among two populations of P. sulphuraria and one population of P. thermalis. Principal component analyses revealed phenotypic and genetic differences among the populations. Evidence for inbreeding was low compared to populations that have undergone habitat reduction. The genetic data were also used to infer the demographic history of these populations to obtain estimates for effective population sizes and migration rates. Effective population sizes were large given the small habitats of these populations. Our results imply that these three endemic extremophile populations should each be considered separately for conservation purposes. Additionally, this study suggests that populations in naturally small habitats may have lower rates of inbreeding and higher genetic diversity than expected, and therefore may be better equipped to handle environmental perturbations than anticipated. We caution, however, that the inferred lack of inbreeding and the large effective population sizes could potentially be a result of colonization by genetically diverse ancestors. © 2017 John Wiley & Sons Ltd.

Polygenic risk score and heritability estimates reveals a genetic relationship between ASD and OCD.

Science.gov (United States)

Guo, W; Samuels, J F; Wang, Y; Cao, H; Ritter, M; Nestadt, P S; Krasnow, J; Greenberg, B D; Fyer, A J; McCracken, J T; Geller, D A; Murphy, D L; Knowles, J A; Grados, M A; Riddle, M A; Rasmussen, S A; McLaughlin, N C; Nurmi, E L; Askland, K D; Cullen, B A; Piacentini, J; Pauls, D L; Bienvenu, O J; Stewart, S E; Goes, F S; Maher, B; Pulver, A E; Valle, D; Mattheisen, M; Qian, J; Nestadt, G; Shugart, Y Y

2017-07-01

Obsessive-compulsive disorder (OCD) and Autism spectrum disorder (ASD) are both highly heritable neurodevelopmental disorders that conceivably share genetic risk factors. However, the underlying genetic determinants remain largely unknown. In this work, the authors describe a combined genome-wide association study (GWAS) of ASD and OCD. The OCD dataset includes 2998 individuals in nuclear families. The ASD dataset includes 6898 individuals in case-parents trios. GWAS summary statistics were examined for potential enrichment of functional variants associated with gene expression levels in brain regions. The top ranked SNP is rs4785741 (chromosome 16) with P value=6.9×10 -7 in our re-analysis. Polygenic risk score analyses were conducted to investigate the genetic relationship within and across the two disorders. These analyses identified a significant polygenic component of ASD, predicting 0.11% of the phenotypic variance in an independent OCD data set. In addition, we examined the genomic architecture of ASD and OCD by estimating heritability on different chromosomes and different allele frequencies, analyzing genome-wide common variant data by using the Genome-wide Complex Trait Analysis (GCTA) program. The estimated global heritability of OCD is 0.427 (se=0.093) and 0.174 (se=0.053) for ASD in these imputed data. Published by Elsevier B.V.

A Knockout Experiment: Disciplinary Divides and Experimental Skill in Animal Behaviour Genetics.

Science.gov (United States)

Nelson, Nicole C

2015-07-01

In the early 1990s, a set of new techniques for manipulating mouse DNA allowed researchers to 'knock out' specific genes and observe the effects of removing them on a live mouse. In animal behaviour genetics, questions about how to deploy these techniques to study the molecular basis of behaviour became quite controversial, with a number of key methodological issues dissecting the interdisciplinary research field along disciplinary lines. This paper examines debates that took place during the 1990s between a predominately North American group of molecular biologists and animal behaviourists around how to design, conduct, and interpret behavioural knockout experiments. Drawing from and extending Harry Collins's work on how research communities negotiate what counts as a 'well-done experiment,' I argue that the positions practitioners took on questions of experimental skill reflected not only the experimental traditions they were trained in but also their differing ontological and epistemological commitments. Different assumptions about the nature of gene action, eg., were tied to different positions in the knockout mouse debates on how to implement experimental controls. I conclude by showing that examining representations of skill in the context of a community's knowledge commitments sheds light on some of the contradictory ways in which contemporary animal behaviour geneticists talk about their own laboratory work as a highly skilled endeavour that also could be mechanised, as easy to perform and yet difficult to perform well.

Speech-language pathologists' knowledge of genetics: perceived confidence, attitudes, knowledge acquisition and practice-based variables.

Science.gov (United States)

Tramontana, G Michael; Blood, Ingrid M; Blood, Gordon W

2013-01-01

The purpose of this study was to determine (a) the general knowledge bases demonstrated by school-based speech-language pathologists (SLPs) in the area of genetics, (b) the confidence levels of SLPs in providing services to children and their families with genetic disorders/syndromes, (c) the attitudes of SLPs regarding genetics and communication disorders, (d) the primary sources used by SLPs to learn about genetic disorders/syndromes, and (e) the association between general knowledge, confidence, attitudes, the number of years of experience working as an SLP, and the number of children currently provided services with genetic disorders/syndromes on SLPs' caseloads. Survey data from a nationwide sample of 533 SLPs was analyzed. Results showed SLPs earned a median knowledge score about genetics of 66% correct responses. Their mean confidence and attitude ratings were in the "unsure" categories while they reported they learned about genetics from three main sources, (a) self-study via web and internet-based searches, (b) on-the-job training and (c) popular press magazines and newspapers. Analyses revealed that Confidence summary scores, Attitude Summary scores, the number of children with genetic disorders/syndromes on SLPs' caseloads are positively associated with the ratings of participants with the highest Knowledge scores. Readers will be able to (a) explain the important links between developmental and communication disabilities and genetics, (b) describe the associations between knowledge about genetics and confidence, attitudes, and the number of children with genetic disorders/syndromes on their caseloads, and (c) outline the clinical and theoretical implications of the results from this study. Copyright © 2012 Elsevier Inc. All rights reserved.

Genome-wide association analysis reveals distinct genetic architectures for single and combined stress responses in Arabidopsis thaliana

NARCIS (Netherlands)

Davila Olivas, Nelson H.; Kruijer, Willem; Gort, Gerrit; Wijnen, Cris L.; Loon, van Joop J.A.; Dicke, Marcel

2017-01-01

Plants are commonly exposed to abiotic and biotic stresses. We used 350 Arabidopsis thaliana accessions grown under controlled conditions. We employed genome-wide association analysis to investigate the genetic architecture and underlying loci involved in genetic variation in resistance to: two

Understanding the impact of genetic testing for inherited retinal dystrophy.

Science.gov (United States)

Combs, Ryan; McAllister, Marion; Payne, Katherine; Lowndes, Jo; Devery, Sophie; Webster, Andrew R; Downes, Susan M; Moore, Anthony T; Ramsden, Simon; Black, Graeme; Hall, Georgina

2013-11-01

The capability of genetic technologies is expanding rapidly in the field of inherited eye disease. New genetic testing approaches will deliver a step change in the ability to diagnose and extend the possibility of targeted treatments. However, evidence is lacking about the benefits of genetic testing to support service planning. Here, we report qualitative data about retinal dystrophy families' experiences of genetic testing in United Kingdom. The data were part of a wider study examining genetic eye service provision. Twenty interviewees from families in which a causative mutation had been identified by a genetic eye clinic were recruited to the study. Fourteen interviewees had chosen to have a genetic test and five had not; one was uncertain. In-depth telephone interviews were conducted allowing a thorough exploration of interviewees' views and experiences of the benefits of genetic counselling and testing. Transcripts were analysed using thematic analysis. Both affected and unaffected interviewees expressed mainly positive views about genetic testing, highlighting benefits such as diagnostic confirmation, risk information, and better preparation for the future. Negative consequences included the burden of knowledge, moral dilemmas around reproduction, and potential impact on insurance. The offer of genetic testing was often taken up, but was felt unnecessary in some cases. Interviewees in the study reported many benefits, suggesting genetic testing should be available to this patient group. The benefits and risks identified will inform future evaluation of models of service delivery. This research was part of a wider study exploring experiences of families with retinal dystrophy.

Genetic structure in contemporary south Tyrolean isolated populations revealed by analysis of Y-chromosome, mtDNA, and Alu polymorphisms.

Science.gov (United States)

Pichler, Irene; Mueller, Jakob C; Stefanov, Stefan A; De Grandi, Alessandro; Volpato, Claudia Beu; Pinggera, Gerd K; Mayr, Agnes; Ogriseg, Martin; Ploner, Franz; Meitinger, Thomas; Pramstaller, Peter P

2006-08-01

Most of the inhabitants of South Tyrol in the eastern Italian Alps can be considered isolated populations because of their physical separation by mountain barriers and their sociocultural heritage. We analyzed the genetic structure of South Tyrolean populations using three types of genetic markers: Y-chromosome, mitochondrial DNA (mtDNA), and autosomal Alu markers. Using random samples taken from the populations of Val Venosta, Val Pusteria, Val Isarco, Val Badia, and Val Gardena, we calculated genetic diversity within and among the populations. Microsatellite diversity and unique event polymorphism diversity (on the Y chromosome) were substantially lower in the Ladin-speaking population of Val Badia compared to the neighboring German-speaking populations. In contrast, the genetic diversity of mtDNA haplotypes was lowest for the upper Val Venosta and Val Pusteria. These data suggest a low effective population size, or little admixture, for the gene pool of the Ladin-speaking population from Val Badia. Interestingly, this is more pronounced for Ladin males than for Ladin females. For the pattern of genetic Alu variation, both Ladin samples (Val Gardena and Val Badia) are among the samples with the lowest diversity. An admixture analysis of one German-speaking valley (Val Venosta) indicates a relatively high genetic contribution of Ladin origin. The reduced genetic diversity and a high genetic differentiation in the Rhaetoroman- and German-speaking South Tyrolean populations may constitute an important basis for future medical genetic research and gene mapping studies in South Tyrol.

Expectations and experiences of gamete donors and donor-conceived adults searching for genetic relatives using DNA linking through a voluntary register.

Science.gov (United States)

van den Akker, O B A; Crawshaw, M A; Blyth, E D; Frith, L J

2015-01-01

What are the experiences of donor-conceived adults and donors who are searching for a genetic link through the use of a DNA-based voluntary register service? Donor-conceived adults and donors held positive beliefs about their search and although some concerns in relation to finding a genetically linked relative were reported, these were not a barrier to searching. Research with donor-conceived people has consistently identified their interest in learning about-and in some cases making contact with-their donor and other genetic relatives. However, donor-conceived individuals or donors rarely have the opportunity to act on these desires. A questionnaire was administered for online completion using Bristol Online Surveys. The survey was live for 3 months and responses were collected anonymously. The survey was completed by 65 donor-conceived adults, 21 sperm donors and 5 oocyte donors who had registered with a DNA-based voluntary contact register in the UK. The questionnaire included socio-demographic questions, questions specifically developed for the purposes of this study and the standardized Aspects of Identity Questionnaire (AIQ). Motivations for searching for genetic relatives were varied, with the most common reasons being curiosity and passing on information. Overall, participants who were already linked and those awaiting a link were positive about being linked and valued access to a DNA-based register. Collective identity (reflecting self-defining feelings of continuity and uniqueness), as assessed by the AIQ, was significantly lower for donor-conceived adults when compared with the donor groups (P 0.05) for donor-conceived adults. Participants were members of a UK DNA-based registry which is unique. It was therefore not possible to determine how representative participants were of those who did not register for the service, those in other countries or of those who do not seek information exchange or contact. This is the first survey exploring the

The economic value of coffee (Coffea arabica) genetic resources

NARCIS (Netherlands)

Hein, L.G.; Gatzweiler, F.

2006-01-01

Whereas the economic value of genetic diversity is widely recognized there are, to date, relatively few experiences with the actual valuation of genetic resources. This paper presents an analysis of the economic value of Coffea arabica genetic resources contained in Ethiopian highland forests. The

Genetic Counsellors and Private Practice: Professional Turbulence and Common Values.

Science.gov (United States)

Collis, Sarah; Gaff, Clara; Wake, Samantha; McEwen, Alison

2017-12-27

Genetic counsellors face tensions between past and future identities: between established values and goals, and a broadening scope of settings and activities. This study examines the advent of genetic counsellors in private practice in Australia and New Zealand from the perspectives of the small numbers working in this sector and those who have only worked in public practice. Semi-structured interviews were conducted with 16 genetic counsellors who had experience in private practice, and 14 genetic counsellors without private sector experience. Results demonstrated that circumstantial and personal factors can mitigate the challenges experienced and the amount of support desired by those who had established a private practice, and those who were employed by private companies. Notably, most participants with private sector experience perceived themselves to be viewed negatively by other genetic counsellors. Most participants without private sector experience expressed concern that the challenges they believed genetic counsellors face in private practice may impact service quality, but wished to address such concerns by providing appropriate support. Together, our results reinforce that participants in private and public sectors are strong advocates for peer support, multidisciplinary team work, and professional development. These core values, and seeking understanding of different circumstances and support needs, will enable genetic counsellors in different sectors to move forward together. Our results suggest supports that may be acted upon by members of the profession, professional groups, and training programs, in Australia, New Zealand, and overseas.

The genetics of radiation-induced osteosarcoma

International Nuclear Information System (INIS)

Rosemann, M.; Kuosaite, V.; Nathrath, M.; Atkinson, M.J.

2002-01-01

Individual genetic variation can influence susceptibility to the carcinogenic effects of many environmental carcinogens. In radiation-exposed populations those individuals with a greater genetically determined susceptibility would be at greater risk of developing cancer. To include this modification of risk into radiation protection schemes it is necessary to identify the genes responsible for determining individual sensitivity. Alpha-particle-induced osteosarcoma in the mouse has been adopted as a model of human radiation carcinogenesis, and genome-wide screens have been conducted for allelic imbalance and genetic linkage. These studies have revealed a series of genes involved in determining the sensitivity to radiogenic osteosarcoma formation. (author)

Genetic monitoring detects an overlooked cryptic species and reveals the diversity and distribution of three invasive Rattus congeners in south Africa

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van Hooft Pim

2011-02-01

Full Text Available Abstract Background South Africa's long and extensive trade activity has ensured ample opportunities for exotic species introduction. Whereas the rich biodiversity of endemic southern African fauna has been the focus of many studies, invasive vertebrates are generally overlooked despite potential impacts on biodiversity, health and agriculture. Genetic monitoring of commensal rodents in South Africa which uncovered the presence of Rattus tanezumi, a South-East Asian endemic not previously known to occur in Africa, provided the impetus for expanded studies on all invasive Rattus species present. Results To this end, intensified sampling at 28 South African localities and at one site in Swaziland, identified 149 Rattus specimens. Cytochrome b gene sequencing revealed the presence of two R. tanezumi, seven Rattus rattus and five Rattus norvegicus haplotypes in south Africa. Phylogenetic results were consistent with a single, recent R. tanezumi introduction and indicated that R. norvegicus and R. rattus probably became established following at least two and three independent introductions, respectively. Intra- and inter-specific diversity was highest in informal human settlements, with all three species occurring at a single metropolitan township site. Rattus norvegicus and R. rattus each occurred sympatrically with Rattus tanezumi at one and five sites, respectively. Karyotyping of selected R. rattus and R. tanezumi individuals identified diploid numbers consistent with those reported previously for these cryptic species. Ordination of bioclimatic variables and MaxEnt ecological niche modelling confirmed that the bioclimatic niche occupied by R. tanezumi in south Africa was distinct from that occupied in its naturalised range in south-east Asia suggesting that factors other than climate may influence the distribution of this species. Conclusions This study has highlighted the value of genetic typing for detecting cryptic invasive species, providing

Molecular genetic differentiation in earthworms inhabiting a heterogeneous Pb-polluted landscape

International Nuclear Information System (INIS)

Andre, J.; King, R.A.; Stuerzenbaum, S.R.; Kille, P.; Hodson, M.E.; Morgan, A.J.

2010-01-01

A Pb-mine site situated on acidic soil, but comprising of Ca-enriched islands around derelict buildings was used to study the spatial pattern of genetic diversity in Lumbricus rubellus. Two distinct genetic lineages ('A' and 'B'), differentiated at both the mitochondrial (mtDNA COII) and nuclear level (AFLPs) were revealed with a mean inter-lineage mtDNA sequence divergence of approximately 13%, indicative of a cryptic species complex. AFLP analysis indicates that lineage A individuals within one central 'ecological island' site are uniquely clustered, with little genetic overlap with lineage A individuals at the two peripheral sites. FTIR microspectroscopy of Pb-sequestering chloragocytes revealed different phosphate profiles in residents of adjacent acidic and calcareous islands. Bioinformatics found over-representation of Ca pathway genes in EST Pb libraries. Subsequent sequencing of a Ca-transport gene, SERCA, revealed mutations in the protein's cytosolic domain. We recommend the mandatory genotyping of all individuals prior to field-based ecotoxicological assays, particularly those using discriminating genomic technologies. - Landscapes punctuated by Pb-polluted islands have engendered local genetic differentiation in resident earthworms.

Genetic testing for hearing impairment.

Science.gov (United States)

Topsakal, V; Van Camp, G; Van de Heyning, P

2005-01-01

For some patients, genetic testing can reveal the etiology of their hearing impairment, and can provide evidence for a medical diagnosis. However, a gap between fundamental genetic research on hereditary deafness and clinical otology emerges because of the steadily increasing number of discovered genes for hereditary hearing impairment (HHI) and the comparably low clinical differentiation of the HHIs. In an attempt to keep up with the scientific progress, this article enumerates the indications of genetic testing for HHI from a clinical point of view and describes the most frequently encountered HHIs in Belgium. Domains of recent scientific interest, molecular biological aspects, and some pitfalls with HHIs are highlighted. The overview comprises bilateral congenital hearing loss, late-onset progressive high frequency hearing loss, progressive bilateral cochleo-vestibular deficit, and progressive low frequency hearing loss. Also, several syndromal forms of HHI are summarized, and the availability of genetic tests mentioned. Finally, the requirements for successful linkage analysis, an important genetic research tool for localizing the potential genes of a trait on a chromosome, are briefly described.

Genetic variability of environmental sensitivity revealed by phenotypic variation in body weight and (its correlations to physiological and behavioral traits.

Directory of Open Access Journals (Sweden)

Delphine Lallias

Full Text Available Adaptive phenotypic plasticity is a key component of the ability of organisms to cope with changing environmental conditions. Fish have been shown to exhibit a substantial level of phenotypic plasticity in response to abiotic and biotic factors. In the present study, we investigate the link between environmental sensitivity assessed globally (revealed by phenotypic variation in body weight and more targeted physiological and behavioral indicators that are generally used to assess the sensitivity of a fish to environmental stressors. We took advantage of original biological material, the rainbow trout isogenic lines, which allowed the disentangling of the genetic and environmental parts of the phenotypic variance. Ten lines were characterized for the changes of body weight variability (weight measurements taken every month during 18 months, the plasma cortisol response to confinement stress (3 challenges and a set of selected behavioral indicators. This study unambiguously demonstrated the existence of genetic determinism of environmental sensitivity, with some lines being particularly sensitive to environmental fluctuations and others rather insensitive. Correlations between coefficient of variation (CV for body weight and behavioral and physiological traits were observed. This confirmed that CV for body weight could be used as an indicator of environmental sensitivity. As the relationship between indicators (CV weight, risk-taking, exploration and cortisol was shown to be likely depending on the nature and intensity of the stressor, the joint use of several indicators should help to investigate the biological complexity of environmental sensitivity.

Human genetic issues from scientific and Islamic perspectives | Alwi ...

African Journals Online (AJOL)

This paper aims at revealing the Human Genome Project (HGP) and human genetic issues arising from science and Islamic perspectives such as Darwin's evolutionary theory, human cloning and eugenics. Finally, issues arising from the applications of human genetic technology need to be addressed to the best possible ...

The Influence of Self-Efficacy Beliefs and Metacognitive Prompting on Genetics Problem Solving Ability among High School Students in Kenya

Science.gov (United States)

Aurah, Catherine Muhonja

Within the framework of social cognitive theory, the influence of self-efficacy beliefs and metacognitive prompting on genetics problem solving ability among high school students in Kenya was examined through a mixed methods research design. A quasi-experimental study, supplemented by focus group interviews, was conducted to investigate both the outcomes and the processes of students' genetics problem-solving ability. Focus group interviews substantiated and supported findings from the quantitative instruments. The study was conducted in 17 high schools in Western Province, Kenya. A total of 2,138 high school students were purposively sampled. A sub-sample of 48 students participated in focus group interviews to understand their perspectives and experiences during the study so as to corroborate the quantitative data. Quantitative data were analyzed through descriptive statistics, zero-order correlations, 2 x 2 factorial ANOVA,, and sequential hierarchical multiple regressions. Qualitative data were transcribed, coded, and reported thematically. Results revealed metacognitive prompts had significant positive effects on student problem-solving ability independent of gender. Self-efficacy and metacognitive prompting significantly predicted genetics problem-solving ability. Gender differences were revealed, with girls outperforming boys on the genetics problem-solving test. Furthermore, self-efficacy moderated the relationship between metacognitive prompting and genetics problem-solving ability. This study established a foundation for instructional methods for biology teachers and recommendations are made for implementing metacognitive prompting in a problem-based learning environment in high schools and science teacher education programs in Kenya.

Re-analysis of public genetic data reveals a rare X-chromosomal variant associated with type 2 diabetes

DEFF Research Database (Denmark)

Bonàs-Guarch, Sílvia; Guindo-Martínez, Marta; Miguel-Escalada, Irene

2018-01-01

The reanalysis of existing GWAS data represents a powerful and cost-effective opportunity to gain insights into the genetics of complex diseases. By reanalyzing publicly available type 2 diabetes (T2D) genome-wide association studies (GWAS) data for 70,127 subjects, we identify seven novel...... available data using novel genetic resources and analytical approaches....... associated with the expression of Angiotensin II Receptor type 2 gene (AGTR2), a modulator of insulin sensitivity, and exhibits allelic specific activity in muscle cells. Beyond providing insights into the genetics and pathophysiology of T2D, these results also underscore the value of reanalyzing publicly...

Using Genetic Algorithms for Building Metrics of Collaborative Systems

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Cristian CIUREA

2011-01-01

Full Text Available he paper objective is to reveal the importance of genetic algorithms in building robust metrics of collaborative systems. The main types of collaborative systems in economy are presented and some characteristics of genetic algorithms are described. A genetic algorithm was implemented in order to determine the local maximum and minimum points of the relative complexity function associated to a collaborative banking system. The intelligent collaborative systems based on genetic algorithms, representing the new generation of collaborative systems, are analyzed and the implementation of auto-adaptive interfaces in a banking application is described.

Ancient DNA reveals substantial genetic diversity in the California Condor (Gymnogyps californianus) prior to a population bottleneck

Science.gov (United States)

D'Elia, Jesse; Haig, Susan M.; Mullins, Thomas D.; Miller, Mark P.

2016-01-01

Critically endangered species that have undergone severe population bottlenecks often have little remaining genetic variation, making it difficult to reconstruct population histories to apply in reintroduction and recovery strategies. By using ancient DNA techniques, it is possible to combine genetic evidence from the historical population with contemporary samples to provide a more complete picture of a species' genetic variation across its historical range and through time. Applying this approach, we examined changes in the mitochondrial DNA (mtDNA) control region (526 base pairs) of the endangered California Condor (Gymnogyps californianus). Results showed a >80% reduction in unique haplotypes over the past 2 centuries. We found no spatial sorting of haplotypes in the historical population; the periphery of the range contained haplotypes that were common throughout the historical range. Direct examination of mtDNA from California Condor museum specimens provided a new window into historical population connectivity and genetic diversity showing: (1) a substantial loss of haplotypes, which is consistent with the hypothesis that condors were relatively abundant in the nineteenth century, but declined rapidly as a result of human-caused mortality; and (2) no evidence of historical population segregation, meaning that the available genetic data offer no cause to avoid releasing condors in unoccupied portions of their historical range.

Ancient DNA from Giant Panda (Ailuropoda melanoleuca) of South-Western China Reveals Genetic Diversity Loss during the Holocene.

Science.gov (United States)

Sheng, Gui-Lian; Barlow, Axel; Cooper, Alan; Hou, Xin-Dong; Ji, Xue-Ping; Jablonski, Nina G; Zhong, Bo-Jian; Liu, Hong; Flynn, Lawrence J; Yuan, Jun-Xia; Wang, Li-Rui; Basler, Nikolas; Westbury, Michael V; Hofreiter, Michael; Lai, Xu-Long

2018-04-06

The giant panda was widely distributed in China and south-eastern Asia during the middle to late Pleistocene, prior to its habitat becoming rapidly reduced in the Holocene. While conservation reserves have been established and population numbers of the giant panda have recently increased, the interpretation of its genetic diversity remains controversial. Previous analyses, surprisingly, have indicated relatively high levels of genetic diversity raising issues concerning the efficiency and usefulness of reintroducing individuals from captive populations. However, due to a lack of DNA data from fossil specimens, it is unknown whether genetic diversity was even higher prior to the most recent population decline. We amplified complete cyt b and 12s rRNA, partial 16s rRNA and ND1 , and control region sequences from the mitochondrial genomes of two Holocene panda specimens. We estimated genetic diversity and population demography by analyzing the ancient mitochondrial DNA sequences alongside those from modern giant pandas, as well as from other members of the bear family (Ursidae). Phylogenetic analyses show that one of the ancient haplotypes is sister to all sampled modern pandas and the second ancient individual is nested among the modern haplotypes, suggesting that genetic diversity may indeed have been higher earlier during the Holocene. Bayesian skyline plot analysis supports this view and indicates a slight decline in female effective population size starting around 6000 years B.P., followed by a recovery around 2000 years ago. Therefore, while the genetic diversity of the giant panda has been affected by recent habitat contraction, it still harbors substantial genetic diversity. Moreover, while its still low population numbers require continued conservation efforts, there seem to be no immediate threats from the perspective of genetic evolutionary potential.

Ancient DNA from Giant Panda (Ailuropoda melanoleuca of South-Western China Reveals Genetic Diversity Loss during the Holocene

Directory of Open Access Journals (Sweden)

Gui-Lian Sheng

2018-04-01

Full Text Available The giant panda was widely distributed in China and south-eastern Asia during the middle to late Pleistocene, prior to its habitat becoming rapidly reduced in the Holocene. While conservation reserves have been established and population numbers of the giant panda have recently increased, the interpretation of its genetic diversity remains controversial. Previous analyses, surprisingly, have indicated relatively high levels of genetic diversity raising issues concerning the efficiency and usefulness of reintroducing individuals from captive populations. However, due to a lack of DNA data from fossil specimens, it is unknown whether genetic diversity was even higher prior to the most recent population decline. We amplified complete cytb and 12s rRNA, partial 16s rRNA and ND1, and control region sequences from the mitochondrial genomes of two Holocene panda specimens. We estimated genetic diversity and population demography by analyzing the ancient mitochondrial DNA sequences alongside those from modern giant pandas, as well as from other members of the bear family (Ursidae. Phylogenetic analyses show that one of the ancient haplotypes is sister to all sampled modern pandas and the second ancient individual is nested among the modern haplotypes, suggesting that genetic diversity may indeed have been higher earlier during the Holocene. Bayesian skyline plot analysis supports this view and indicates a slight decline in female effective population size starting around 6000 years B.P., followed by a recovery around 2000 years ago. Therefore, while the genetic diversity of the giant panda has been affected by recent habitat contraction, it still harbors substantial genetic diversity. Moreover, while its still low population numbers require continued conservation efforts, there seem to be no immediate threats from the perspective of genetic evolutionary potential.

Plasmodium vivax merozoite surface protein-3 alpha: a high-resolution marker for genetic diversity studies.

Science.gov (United States)

Prajapati, Surendra Kumar; Joshi, Hema; Valecha, Neena

2010-06-01

Malaria, an ancient human infectious disease caused by five species of Plasmodium, among them Plasmodium vivax is the most widespread human malaria species and causes huge morbidity to its host. Identification of genetic marker to resolve higher genetic diversity for an ancient origin organism is a crucial task. We have analyzed genetic diversity of P. vivax field isolates using highly polymorphic antigen gene merozoite surface protein-3 alpha (msp-3 alpha) and assessed its suitability as high-resolution genetic marker for population genetic studies. 27 P. vivax field isolates collected during chloroquine therapeutic efficacy study at Chennai were analyzed for genetic diversity. PCR-RFLP was employed to assess the genetic variations using highly polymorphic antigen gene msp-3 alpha. We observed three distinct PCR alleles at msp-3 alpha, and among them allele A showed significantly high frequency (53%, chi2 = 8.22, p = 0.001). PCR-RFLP analysis revealed 14 and 17 distinct RFLP patterns for Hha1 and Alu1 enzymes respectively. Further, RFLP analysis revealed that allele A at msp-3 alpha is more diverse in the population compared with allele B and C. Combining Hha1 and Alu1 RFLP patterns revealed 21 distinct genotypes among 22 isolates reflects higher diversity resolution power of msp-3 alpha in the field isolates. P. vivax isolates from Chennai region revealed substantial amount of genetic diversity and comparison of allelic diversity with other antigen genes and microsatellites suggesting that msp-3 alpha could be a high-resolution marker for genetic diversity studies among P. vivax field isolates.

Genetic diversity characterization of cassava cultivars (Manihot esculenta Crantz.: I RAPD markers

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Colombo Carlos

1998-01-01

Full Text Available RAPD markers were used to investigate the genetic diversity of 31 Brazilian cassava clones. The results were compared with the genetic diversity revealed by botanical descriptors. Both sets of variates revealed identical relationships among the cultivars. Multivariate analysis of genetic similarities placed genotypes destinated for consumption "in nature" in one group, and cultivars useful for flour production in another. Brazil?s abundance of landraces presents a broad dispersion and is consequently an important resource of genetic variability. The botanical descriptors were not able to differentiate thirteen pairs of cultivars compared two-by-two, while only one was not differentiated by RAPD markers. These results showed the power of RAPD markers over botanical descriptors in studying genetic diversity, identifying duplicates, as well as validating, or improving a core collection. The latter is particularly important in this vegetatively propagated crop.

From Novice to Seasoned Practitioner: a Qualitative Investigation of Genetic Counselor Professional Development.

Science.gov (United States)

Zahm, Kimberly Wehner; Veach, Patricia McCarthy; Martyr, Meredith A; LeRoy, Bonnie S

2016-08-01

Research on genetic counselor professional development would characterize typical developmental processes, inform training and supervision, and promote life-long development opportunities. To date, however no studies have comprehensively examined this phenomenon. The aims of this study were to investigate the nature of professional development for genetic counselors (processes, influences, and outcomes) and whether professional development varies across experience levels. Thirty-four genetic counselors participated in semi-structured telephone interviews exploring their perspectives on their professional development. Participants were sampled from three levels of post-degree genetic counseling experience: novice (0-5 years), experienced (6-14 years), and seasoned (>15 years). Using modified Consensual Qualitative Research and grounded theory methods, themes, domains, and categories were extracted from the data. The themes reflect genetic counselors' evolving perceptions of their professional development and its relationship to: (a) being a clinician, (b) their professional identity, and (c) the field itself. Across experience levels, prevalent influences on professional development were interpersonal (e.g., experiences with patients, genetic counseling colleagues) and involved professional and personal life events. Common developmental experiences included greater confidence and less anxiety over time, being less information-driven and more emotion-focused with patients, delivering "bad news" to patients remains challenging, and individuals' professional development experiences parallel genetic counseling's development as a field. With a few noteworthy exceptions, professional development was similar across experience levels. A preliminary model of genetic counselor professional development is proposed suggesting development occurs in a non-linear fashion throughout the professional lifespan. Each component of the model mutually influences the others, and there

Broad-scale sampling of primary freshwater fish populations reveals the role of intrinsic traits, inter-basin connectivity, drainage area and latitude on shaping contemporary patterns of genetic diversity

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Carla Sousa-Santos

2016-02-01

Full Text Available Background. Worldwide predictions suggest that up to 75% of the freshwater fish species occurring in rivers with reduced discharge could be extinct by 2070 due to the combined effect of climate change and water abstraction. The Mediterranean region is considered to be a hotspot of freshwater fish diversity but also one of the regions where the effects of climate change will be more severe. Iberian cyprinids are currently highly endangered, with over 68% of the species raising some level of conservation concern. Methods. During the FISHATLAS project, the Portuguese hydrographical network was extensively covered (all the 34 river basins and 47 sub-basins in order to contribute with valuable data on the genetic diversity distribution patterns of native cyprinid species. A total of 188 populations belonging to 16 cyprinid species of Squalius, Luciobarbus, Achondrostoma, Iberochondrostoma, Anaecypris and Pseudochondrostoma were characterized, for a total of 3,678 cytochrome b gene sequences. Results. When the genetic diversity of these populations was mapped, it highlighted differences among populations from the same species and between species with identical distribution areas. Factors shaping the contemporary patterns of genetic diversity were explored and the results revealed the role of latitude, inter-basin connectivity, migratory behaviour, species maximum size, species range and other species intrinsic traits in determining the genetic diversity of sampled populations. Contrastingly, drainage area and hydrological regime (permanent vs. temporary seem to have no significant effect on genetic diversity. Species intrinsic traits, maximum size attained, inter-basin connectivity and latitude explained over 30% of the haplotype diversity variance and, generally, the levels of diversity were significantly higher for smaller sized species, from connected and southerly river basins. Discussion. Targeting multiple co-distributed species of primary

Genetics of human body size and shape: pleiotropic and independent genetic determinants of adiposity.

Science.gov (United States)

Livshits, G; Yakovenko, K; Ginsburg, E; Kobyliansky, E

1998-01-01

The present study utilized pedigree data from three ethnically different populations of Kirghizstan, Turkmenia and Chuvasha. Principal component analysis was performed on a matrix of genetic correlations between 22 measures of adiposity, including skinfolds, circumferences and indices. Findings are summarized as follows: (1) All three genetic matrices were not positive definite and the first four factors retained even after exclusion RG > or = 1.0, explained from 88% to 97% of the total additive genetic variation in the 22 trials studied. This clearly emphasizes the massive involvement of pleiotropic gene effects in the variability of adiposity traits. (2) Despite the quite natural differences in pairwise correlations between the adiposity traits in the three ethnically different samples under study, factor analysis revealed a common basic pattern of covariability for the adiposity traits. In each of the three samples, four genetic factors were retained, namely, the amount of subcutaneous fat, the total body obesity, the pattern of distribution of subcutaneous fat and the central adiposity distribution. (3) Genetic correlations between the retained four factors were virtually non-existent, suggesting that several independent genetic sources may be governing the variation of adiposity traits. (4) Variance decomposition analysis on the obtained genetic factors leaves no doubt regarding the substantial familial and (most probably genetic) effects on variation of each factor in each studied population. The similarity of results in the three different samples indicates that the findings may be deemed valid and reliable descriptions of the genetic variation and covariation pattern of adiposity traits in the human species.

Genetic and morphological differentiation between Melica ciliata L. and M. transsilvanica Schur (Poaceae in Europe reveals the non-presence of M. ciliata in the Polish flora

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Magdalena Szczepaniak

2011-12-01

Full Text Available A good knowledge of species delimitation is crucial for the biodiversity protection and the conservation of wild species. We studied the efficiency of AFLP markers and morphological characters to assist species determination for Melica ciliata L. and M. transsilvanica Schur within European range of distribution, including isolated and range-limit populations of "M. ciliata" (i.e. M. cf. ciliata from the Polish Sudetes, where it is regarded as critically endangered. AFLP markers were found to be more effective then morphological characters (more or less continuous in distinguishing the both studied species. AMOVA revealed very low genetic diversity within populations and high differentiation among populations of M. ciliata and M. transsilvanica (FST = 0.89 and 0.95, respectively. The species-diagnostic AFLP markers of M. transsilvanica shared with "M. ciliata" from the Sudetes were detected. On the other hand, no species-diagnostic genetic markers of M. ciliata or hybrid-diagnostic markers of M. × thuringiaca were found within "M. ciliata". PCoA and NJ showed an overlapping genetic diversity of "M. ciliata" and M. transsilvanica. Hierar­chical AMOVA supported the absence of a significant genotypic distinction between "M. ciliata" and M. transsilvanica. ANOVA showed that the length ratio of lower to upper glumes was the best morphological character to discriminate between M. ciliata and M. transsilvanica. Combined morphological and genetic data show that M. ciliata is not currently present in Poland as its putative Polish populations represent M. transsilvanica. A significant decrease in genetic varia­bility that could influence viability was not observed the in Sudetian populations of M. transsilvanica. However, the population size changes significantly as a result of plant succession. Correction of the northern limit of the continuous distribution of M. ciliata L. in Central Europe is presented.

Genetic diversity in wheat germplasm collections from Balochistan province of Pakistan

International Nuclear Information System (INIS)

Khan, A.A.; Iqbal, A.; Awan, F.S.; Khan, I.A.

2010-01-01

Productivity of wheat varieties being bred for the last many years is stagnant in Pakistan, apparently because of the narrowed genetic base of their parental lines. As a part of the national wheat germplasm characterization programme, we examined genetic diversity among 75 accessions of wheat using RAPD markers and assessed the relationship and genetic distance between them. The accessions surveyed were comprised of land race populations of Triticum aestivum L., collected from various districts of the Balochistan province of Pakistan, which is considered a reservoir of genetic diversity, particularly for wheat. The genetic similarity revealed by RAPD markers among the wheat accessions was medium to high. The accessions collected from Sibi and Pishin districts had the greatest similarity. The polymorphism revealed in the wheat accessions, appeared to be distributed with the location of collections. The high degree of similarity even among the presumably land race material emphasizes the need for the expansion of germplasm resources and development of wheat varieties with diverse genetic background, which could substantiate the wheat breeding programmes to increase its productivity. (author)

Perspectives on Genetic and Genomic Technologies in an Academic Medical Center: The Duke Experience

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Katsanis, Sara Huston; Minear, Mollie A.; Vorderstrasse, Allison; Yang, Nancy; Reeves, Jason W.; Rakhra-Burris, Tejinder; Cook-Deegan, Robert; Ginsburg, Geoffrey S.; Simmons, Leigh Ann

2015-01-01

In this age of personalized medicine, genetic and genomic testing is expected to become instrumental in health care delivery, but little is known about its actual implementation in clinical practice. Methods. We surveyed Duke faculty and healthcare providers to examine the extent of genetic and genomic testing adoption. We assessed providers’ use of genetic and genomic testing options and indications in clinical practice, providers’ awareness of pharmacogenetic applications, and providers’ opinions on returning research-generated genetic test results to participants. Most clinician respondents currently use family history routinely in their clinical practice, but only 18 percent of clinicians use pharmacogenetics. Only two respondents correctly identified the number of drug package inserts with pharmacogenetic indications. We also found strong support for the return of genetic research results to participants. Our results demonstrate that while Duke healthcare providers are enthusiastic about genomic technologies, use of genomic tools outside of research has been limited. Respondents favor return of research-based genetic results to participants, but clinicians lack knowledge about pharmacogenetic applications. We identified challenges faced by this institution when implementing genetic and genomic testing into patient care that should inform a policy and education agenda to improve provider support and clinician-researcher partnerships. PMID:25854543

Perspectives on Genetic and Genomic Technologies in an Academic Medical Center: The Duke Experience

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Sara Huston Katsanis

2015-04-01

Full Text Available In this age of personalized medicine, genetic and genomic testing is expected to become instrumental in health care delivery, but little is known about its actual implementation in clinical practice. Methods. We surveyed Duke faculty and healthcare providers to examine the extent of genetic and genomic testing adoption. We assessed providers’ use of genetic and genomic testing options and indications in clinical practice, providers’ awareness of pharmacogenetic applications, and providers’ opinions on returning research-generated genetic test results to participants. Most clinician respondents currently use family history routinely in their clinical practice, but only 18 percent of clinicians use pharmacogenetics. Only two respondents correctly identified the number of drug package inserts with pharmacogenetic indications. We also found strong support for the return of genetic research results to participants. Our results demonstrate that while Duke healthcare providers are enthusiastic about genomic technologies, use of genomic tools outside of research has been limited. Respondents favor return of research-based genetic results to participants, but clinicians lack knowledge about pharmacogenetic applications. We identified challenges faced by this institution when implementing genetic and genomic testing into patient care that should inform a policy and education agenda to improve provider support and clinician-researcher partnerships.

Using genetic information while protecting the privacy of the soul.

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Moor, J H

1999-01-01

Computing plays an important role in genetics (and vice versa). Theoretically, computing provides a conceptual model for the function and malfunction of our genetic machinery. Practically, contemporary computers and robots equipped with advanced algorithms make the revelation of the complete human genome imminent--computers are about to reveal our genetic souls for the first time. Ethically, computers help protect privacy by restricting access in sophisticated ways to genetic information. But the inexorable fact that computers will increasingly collect, analyze, and disseminate abundant amounts of genetic information made available through the genetic revolution, not to mention that inexpensive computing devices will make genetic information gathering easier, underscores the need for strong and immediate privacy legislation.

Genetic diversity and relationship of global faba bean (Vicia faba L.) germplasm revealed by ISSR markers.

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Wang, Hai-Fei; Zong, Xu-Xiao; Guan, Jian-Ping; Yang, Tao; Sun, Xue-Lian; Ma, Yu; Redden, Robert

2012-03-01

Genetic diversity and relationships of 802 faba bean (Vicia faba L.) landraces and varieties from different geographical locations of China and abroad were examined using ISSR markers. A total of 212 repeatable amplified bands were generated with 11 ISSR primers, of which 209 were polymorphic. Accessions from North China showed highest genetic diversity, while accessions from central China showed low level of diversity. Chinese spring faba bean germplasm was clearly separated from Chinese winter faba bean, based on principal component analysis and UPGMA clustering analysis. Winter accessions from Zhejiang (East China), Jiangxi (East China), Sichuan (Southwest China) and Guizhou (Southwest China) were quite distinct to that from other provinces in China. Great differentiation between Chinese accessions and those from rest of the world was shown with a UPGMA dendrogram. AMOVA analyses demonstrated large variation and differentiation within and among groups of accessions from China. As a continental geographic group, accessions from Europe were genetically closer to those from North Africa. Based on ISSR data, grouping results of accessions from Asia, Europe and Africa were obviously associated with their geographical origin. The overall results indicated that the genetic relationship of faba bean germplasm was closely associated with their geographical origin and their ecological habit.

Evaluation of genetic diversity of Panicum turgidum Forssk from Saudi Arabia.

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Assaeed, Abdulaziz M; Al-Faifi, Sulieman A; Migdadi, Hussein M; El-Bana, Magdy I; Al Qarawi, Abdulaziz A; Khan, Mohammad Altaf

2018-01-01

The genetic diversity of 177 accessions of Panicum turgidum Forssk, representing ten populations collected from four geographical regions in Saudi Arabia, was analyzed using amplified fragment length polymorphism (AFLP) markers. A set of four primer-pairs with two/three selective nucleotides scored 836 AFLP amplified fragments (putative loci/genome landmarks), all of which were polymorphic. Populations collected from the southern region of the country showed the highest genetic diversity parameters, whereas those collected from the central regions showed the lowest values. Analysis of molecular variance (AMOVA) revealed that 78% of the genetic variability was attributable to differences within populations. Pairwise values for population differentiation and genetic structure were statistically significant for all variances. The UPGMA dendrogram, validated by principal coordinate analysis-grouped accessions, corresponded to the geographical origin of the accessions. Mantel's test showed that there was a significant correlation between the genetic and geographical distances ( r  = 0.35, P  < 0.04). In summary, the AFLP assay demonstrated the existence of substantial genetic variation in P. turgidum . The relationship between the genetic diversity and geographical source of P. turgidum populations of Saudi Arabia, as revealed through this comprehensive study, will enable effective resource management and restoration of new areas without compromising adaptation and genetic diversity.

Combination of RNAseq and SNP nanofluidic array reveals the center of genetic diversity of cacao pathogen Moniliophthora roreri in the upper Magdalena Valley of Colombia and its clonality

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Shahin S Ali

2015-08-01

Full Text Available Moniliophthora roreri is the fungal pathogen that causes frosty pod rot (FPR disease of Theobroma cacao L., the source of chocolate. FPR occurs in most of the cacao producing countries in the Western Hemisphere, causing yield losses up to 80%. Genetic diversity within the FPR pathogen population may allow the population to adapt to changing environmental conditions and adapt to enhanced resistance in the host plant. The present study developed SNP markers from RNASeq results for 13 M. roreri isolates and validated the markers for their ability to reveal genetic diversity in an international M. roreri collection. The SNP resources reported herein represent the first study of RNASeq-derived SNP validation in M. roreri and demonstrates the utility of RNASeq as an approach for de novo SNP identification in M. roreri. A total of 88 polymorphic SNPs were used to evaluate the genetic diversity of 172 M. roreri cacao isolates resulting in 37 distinct genotypes (including 14 synonymous groups. Absence of heterozygosity for the 88 SNP markers indicates reproduction in M. roreri is clonal and likely due to a homothallic life style. The upper Magdalena Valley of Colombia showed the highest levels of genetic diversity with 20 distinct genotypes of which 13 were limited to this region, and indicates this region as the possible center of origin for M. roreri.

Combination of RNAseq and SNP nanofluidic array reveals the center of genetic diversity of cacao pathogen Moniliophthora roreri in the upper Magdalena Valley of Colombia and its clonality.

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Ali, Shahin S; Shao, Jonathan; Strem, Mary D; Phillips-Mora, Wilberth; Zhang, Dapeng; Meinhardt, Lyndel W; Bailey, Bryan A

2015-01-01

Moniliophthora roreri is the fungal pathogen that causes frosty pod rot (FPR) disease of Theobroma cacao L., the source of chocolate. FPR occurs in most of the cacao producing countries in the Western Hemisphere, causing yield losses up to 80%. Genetic diversity within the FPR pathogen population may allow the population to adapt to changing environmental conditions and adapt to enhanced resistance in the host plant. The present study developed single nucleotide polymorphism (SNP) markers from RNASeq results for 13 M. roreri isolates and validated the markers for their ability to reveal genetic diversity in an international M. roreri collection. The SNP resources reported herein represent the first study of RNA sequencing (RNASeq)-derived SNP validation in M. roreri and demonstrates the utility of RNASeq as an approach for de novo SNP identification in M. roreri. A total of 88 polymorphic SNPs were used to evaluate the genetic diversity of 172 M. roreri cacao isolates resulting in 37 distinct genotypes (including 14 synonymous groups). Absence of heterozygosity for the 88 SNP markers indicates reproduction in M. roreri is clonal and likely due to a homothallic life style. The upper Magdalena Valley of Colombia showed the highest levels of genetic diversity with 20 distinct genotypes of which 13 were limited to this region, and indicates this region as the possible center of origin for M. roreri.

Insight into the genetic components of community genetics: QTL mapping of insect association in a fast-growing forest tree.

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Jennifer DeWoody

Full Text Available Identifying genetic sequences underlying insect associations on forest trees will improve the understanding of community genetics on a broad scale. We tested for genomic regions associated with insects in hybrid poplar using quantitative trait loci (QTL analyses conducted on data from a common garden experiment. The F2 offspring of a hybrid poplar (Populus trichocarpa x P. deltoides cross were assessed for seven categories of insect leaf damage at two time points, June and August. Positive and negative correlations were detected among damage categories and between sampling times. For example, sap suckers on leaves in June were positively correlated with sap suckers on leaves (P<0.001 but negatively correlated with skeletonizer damage (P<0.01 in August. The seven forms of leaf damage were used as a proxy for seven functional groups of insect species. Significant variation in insect association occurred among the hybrid offspring, including transgressive segregation of susceptibility to damage. NMDS analyses revealed significant variation and modest broad-sense heritability in insect community structure among genets. QTL analyses identified 14 genomic regions across 9 linkage groups that correlated with insect association. We used three genomics tools to test for putative mechanisms underlying the QTL. First, shikimate-phenylpropanoid pathway genes co-located to 9 of the 13 QTL tested, consistent with the role of phenolic glycosides as defensive compounds. Second, two insect association QTL corresponded to genomic hotspots for leaf trait QTL as identified in previous studies, indicating that, in addition to biochemical attributes, leaf morphology may influence insect preference. Third, network analyses identified categories of gene models over-represented in QTL for certain damage types, providing direction for future functional studies. These results provide insight into the genetic components involved in insect community structure in a fast

The ethical implications of genetic testing in the classroom.

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Taylor, Ann T S; Rogers, Jill Cellars

2011-07-01

The development of classroom experiments where students examine their own DNA is frequently described as an innovative teaching practice. Often these experiences involve students analyzing their genes for various polymorphisms associated with disease states, like an increased risk for developing cancer. Such experiments can muddy the distinction between classroom investigation and medical testing. Although the goals and issues surrounding classroom genotyping do not directly align with those of clinical testing, instructors can use the guidelines and standards established by the medical genetics community when evaluating the ethics of human genotyping. We developed a laboratory investigation and discussion which allowed undergraduate science students to explore current DNA manipulation techniques to isolate their p53 gene, followed by a dialogue probing the ethical implications of examining their sample for various polymorphisms. Students never conducted genotyping on their samples because of the ethical concerns presented in this paper, so the discussion replaced the actual genetic testing in the class. A science faculty member led the laboratory portion, while a genetic counselor facilitated the discussion of the ethical concepts underlying genetic counseling: autonomy, beneficence, confidentiality, and justice. In their final papers, students demonstrated an understanding of the practice guidelines established by the genetics community and acknowledged the ethical considerations inherent in p53 genotyping. Given the burgeoning market for personalized medicine, teaching undergraduates about the psychosocial and ethical dimensions of human genetic testing is important and timely. Moreover, incorporating a genetic counselor in the classroom discussion provided a rich and dynamic discussion of human genetic testing. Copyright © 2011 Wiley Periodicals, Inc.

Landscape genetics reveals inbreeding and genetic bottlenecks in the extremely rare short-globose cacti Mammillaria pectinifera (Cactaceae as a result of habitat fragmentation

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Reyna Maya-García

2017-02-01

Full Text Available Mammillaria pectinifera is an endemic, short-globose cactus species, included in the IUCN list as a threatened species with only 18 remaining populations in the Tehuacán-Cuicatlán Valley in central Mexico. We evaluated the population genetic diversity and structure, connectivity, recent bottlenecks and population size, using nuclear microsatellites. M. pectinifera showed high genetic diversity but some evidence of heterozygote deficiency (FIS, recent bottlenecks in some populations and reductions in population size. Also, we found low population genetic differentiation and high values of connectivity for M. pectinifera, as the result of historical events of gene flow through pollen and seed dispersal. M. pectinifera occurs in sites with some degree of disturbance leading to the isolation of its populations and decreasing the levels of gene flow among them. Excessive deforestation also changes the original vegetation damaging the natural habitats. This species will become extinct if it is not properly preserved. Furthermore, this species has some ecological features that make them more vulnerable to disturbance such as a very low growth rates and long life cycles. We suggest in situ conservation to prevent the decrease of population sizes and loss of genetic diversity in the natural protected areas such as the Tehuacán-Cuicatlán Biosphere Reserve. In addition, a long-term ex situ conservation program is need to construct seed banks, and optimize seed germination and plant establishment protocols that restore disturbed habitats. Furthermore, creating a supply of living plants for trade is critical to avoid further extraction of plants from nature.

In vivo MRS metabolite quantification using genetic optimization

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Papakostas, G. A.; Karras, D. A.; Mertzios, B. G.; van Ormondt, D.; Graveron-Demilly, D.

2011-11-01

The in vivo quantification of metabolites' concentrations, revealed in magnetic resonance spectroscopy (MRS) spectra, constitutes the main subject under investigation in this work. Significant contributions based on artificial intelligence tools, such as neural networks (NNs), with good results have been presented lately but have shown several drawbacks, regarding their quantification accuracy under difficult conditions. A general framework that encounters the quantification procedure as an optimization problem, which is solved using a genetic algorithm (GA), is proposed in this paper. Two different lineshape models are examined, while two GA configurations are applied on artificial data. Moreover, the introduced quantification technique deals with metabolite peaks' overlapping, a considerably difficult situation occurring under real conditions. Appropriate experiments have proved the efficiency of the introduced methodology, in artificial MRS data, by establishing it as a generic metabolite quantification procedure.

In vivo MRS metabolite quantification using genetic optimization

International Nuclear Information System (INIS)

Papakostas, G A; Mertzios, B G; Karras, D A; Van Ormondt, D; Graveron-Demilly, D

2011-01-01

The in vivo quantification of metabolites' concentrations, revealed in magnetic resonance spectroscopy (MRS) spectra, constitutes the main subject under investigation in this work. Significant contributions based on artificial intelligence tools, such as neural networks (NNs), with good results have been presented lately but have shown several drawbacks, regarding their quantification accuracy under difficult conditions. A general framework that encounters the quantification procedure as an optimization problem, which is solved using a genetic algorithm (GA), is proposed in this paper. Two different lineshape models are examined, while two GA configurations are applied on artificial data. Moreover, the introduced quantification technique deals with metabolite peaks' overlapping, a considerably difficult situation occurring under real conditions. Appropriate experiments have proved the efficiency of the introduced methodology, in artificial MRS data, by establishing it as a generic metabolite quantification procedure

Environmental chemical mutagens and genetic risks: Lessons from radiation genetics

International Nuclear Information System (INIS)

Sankaranarayanan, K.

1996-01-01

The last three decades have witnessed substantial progress in the development and use of a variety of in vitro and in vivo assay systems for the testing of environmental chemicals which may pose a mutagenic hazard to humans. This is also true of basic studies in chemical mutagenesis on mechanisms, DNA repair, molecular dosimetry, structure-activity relationships, etc. However, the field of quantitative evaluation of genetic risks of environmental chemicals to humans is still in it infancy. This commentary addresses the question of how our experience in estimating genetic risks of exposure to ionizing radiation can be helpful in similar endeavors with environmental chemical mutagens. 24 refs., 3 tabs

Genetic variability of cultivated cowpea in Benin assessed by ...

African Journals Online (AJOL)

STORAGESEVER

2008-12-17

Dec 17, 2008 ... Res. Crop Evol. 48: 559-566. Mignouna HD, Ng NQ, Ikea J, Thottapilly G (1998). Genetic diversity in cowpea as revealed by random amplified polymorphic DNA. J. Gen. Breed. 52: 151-159. Nei M, Li WH (1979). Mathematical model for studying genetic variation in terms of restriction endonucleases. Proc.

Education and certification of genetic counselors.

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Katsichti, L; Hadzipetros-Bardanis, M; Bartsocas, C S

1999-01-01

Genetic counseling is defined by the American Society of Human Genetics as a communication process which deals with the human problems associated with the occurrence, or risk of occurrence, of a genetic disorder in a family. The first graduate program (Master's degree) in genetic counseling started in 1969 at Sarah Lawrence College, NY, USA, while in 1979 the National Society of Genetic Counseling (NSGC) was established. Today, there are 29 programs in U.S.A. offering a Master's degree in Genetic Counseling, five programs in Canada, one in Mexico, one in England and one in S. Africa. Most of these graduate programs offer two year training, consisting of graduate courses, seminars, research and practical training. Emphasis is given in human physiology, biochemistry, clinical genetics, cytogenetics, molecular and biochemical genetics, population genetics and statistics, prenatal diagnosis, teratology and genetic counseling in relation to psychosocial and ethical issues. Certification for eligible candidates is available through the American Board of Medical Genetics (ABMG). Requirements for certification include a master's degree in human genetics, training at sites accredited by the ABMG, documentation of genetic counseling experience, evidence of continuing education and successful completion of a comprehensive ABMG certification examination. As professionals, genetic counselors should maintain expertise, should insure mechanisms for professional advancement and should always maintain the ability to approach their patients.

Genetic diversity of Plasmodium Vivax revealed by the merozoite surface protein-1 icb5-6 fragment.

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Ruan, Wei; Zhang, Ling-Ling; Feng, Yan; Zhang, Xuan; Chen, Hua-Liang; Lu, Qiao-Yi; Yao, Li-Nong; Hu, Wei

2017-06-05

Plasmodium vivax remains a potential cause of morbidity and mortality for people living in its endemic areas. Understanding the genetic diversity of P. vivax from different regions is valuable for studying population dynamics and tracing the origins of parasites. The PvMSP-1 gene is highly polymorphic and has been used as a marker in many P. vivax population studies. The aim of this study was to investigate the genetic diversity of the PvMSP-1 gene icb5-6 fragment and to provide more genetic polymorphism data for further studies on P. vivax population structure and tracking of the origin of clinical cases. Nested PCR and sequencing of the PvMSP-1 icb5-6 marker were performed to obtain the nucleotide sequences of 95 P. vivax isolates collected from Zhejiang province, China. To investigate the genetic diversity of PvMSP-1, the 95 nucleotide sequences of the PvMSP-1 icb5-6 fragment were genotyped and analyzed using DnaSP v5, MEGA software. The 95 P. vivax isolates collected from Zhejiang province were either indigenous cases or imported cases from different regions around the world. A total of 95 sequences ranging from 390 to 460 bp were obtained. The 95 sequences were genotyped into four allele-types (Sal I, Belem, R-III and R-IV) and 17 unique haplotypes. R-III and Sal I were the predominant allele-types. The haplotype diversity (Hd) and nucleotide diversity (Pi) were estimated to be 0.729 and 0.062, indicating that the PvMSP-1 icb5-6 fragment had the highest level of polymorphism due to frequent recombination processes and single nucleotide polymorphism. The values of dN/dS and Tajima's D both suggested neutral selection for the PvMSP-1icb5-6 fragment. In addition, a rare recombinant style of R-IV type was identified. This study presented high genetic diversity in the PvMSP-1 marker among P. vivax strains from around the world. The genetic data is valuable for expanding the polymorphism information on P. vivax, which could be helpful for further study on

Conservation genetics of managed ungulate populations

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Scribner, Kim T.

1993-01-01

Natural populations of many species are increasingly impacted by human activities. Perturbations are particularly pronunced for large ungulates due in part to sport and commercial harvest, to reductions and fragmentation of native habitat, and as the result of reintroductions. These perturbations affect population size, sex and age composition, and population breeding structure, and as a consequence affect the levels and partitioning of genetic variation. Three case histories highlighting long-term ecological genetic research on mule deer Odocoileus hemionus (Rafinesque, 1817), white-tailed deer O. virginianus (Zimmermann, 1780), and Alpine ibex Capra i. ibex Linnaeus, 1758 are presented. Joint examinations of population ecological and genetic data from several populations of each species reveal: (1) that populations are not in genetic equilibrium, but that allele frequencies and heterozygosity change dramatically over time and among cohorts produced in successive years, (2) populations are genetically structured over short and large geographic distances reflecting local breeding structure and patterns of gene flow, respectively; however, this structure is quite dynamic over time, due in part to population exploitation, and (3) restocking programs are often undertaken with small numbers of founding individuals resulting in dramatic declines in levels of genetic variability and increasing levels of genetic differentiation among populations due to genetic drift. Genetic characteristics have and will continue to provide valuable indirect sources of information relating enviromental and human perturbations to changes in population processes.

Characterization of Pearl Millet Root Architecture and Anatomy Reveals Three Types of Lateral Roots

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Passot, Sixtine; Gnacko, Fatoumata; Moukouanga, Daniel; Lucas, Mikaël; Guyomarc’h, Soazig; Ortega, Beatriz Moreno; Atkinson, Jonathan A.; Belko, Marème N.; Bennett, Malcolm J.; Gantet, Pascal; Wells, Darren M.; Guédon, Yann; Vigouroux, Yves; Verdeil, Jean-Luc; Muller, Bertrand; Laplaze, Laurent

2016-01-01

Pearl millet plays an important role for food security in arid regions of Africa and India. Nevertheless, it is considered an orphan crop as it lags far behind other cereals in terms of genetic improvement efforts. Breeding pearl millet varieties with improved root traits promises to deliver benefits in water and nutrient acquisition. Here, we characterize early pearl millet root system development using several different root phenotyping approaches that include rhizotrons and microCT. We report that early stage pearl millet root system development is characterized by a fast growing primary root that quickly colonizes deeper soil horizons. We also describe root anatomical studies that revealed three distinct types of lateral roots that form on both primary roots and crown roots. Finally, we detected significant variation for two root architectural traits, primary root lenght and lateral root density, in pearl millet inbred lines. This study provides the basis for subsequent genetic experiments to identify loci associated with interesting early root development traits in this important cereal. PMID:27379124

Bioethics, sport and the genetically enhanced athlete.

Science.gov (United States)

Miah, Andy

2002-01-01

This paper begins by acknowledging the interest taken by various international organisations in genetic enhancement and sport, including the US President's Council on Bioethics (July, 2002) and the World Anti-Doping Agency (March, 2002). It is noticed how sporting organisations have been particularly concerned to emphasize the 'threat' of genetics to sport, whereas other institutions have recognised the broader bioethical issues arising from this prospect, which do not readily reject the use of genetic technology in sport. Sports are identified as necessarily 'human' and 'moral' practices, the exploration of which can reveal greater insight into the intuitive fears about genetic modification. It is argued that anti-doping testing measures and sanctions unacceptably persecute the athlete. While there are substantial reasons to be concerned about the use of genetic modification in sport, the desire for policy ought not diminish the need for ethical research; nor ought such research embody the similar guise of traditional 'anti' doping strategies. Rather, the approach to genetics in sport must be informed more by broader social policies in bioethics and recognition of the greater goods arising from genetic technology.

Analyses between Reproductive Behavior, Genetic Diversity and Pythium Responsiveness in Zingiber spp. Reveal an Adaptive Significance for Hemiclonality

Science.gov (United States)

Thomas, Geethu E.; Geetha, Kiran A.; Augustine, Lesly; Mamiyil, Sabu; Thomas, George

2016-01-01

Mode of reproduction is generally considered to have long-range evolutionary implications on population survival. Because sexual reproduction produces genetically diverse genotypes, this mode of reproduction is predicted to positively influence the success potential of offspring in evolutionary arms race with parasites (Red queen) whereas, without segregation and recombination, the obligate asexual multiplication may push a species into extinction due to the steady accumulation of deleterious mutations (Muller’s ratchet). However, the extent of linearity between reproductive strategies, genetic diversity and population fitness, and the contributions of different breeding strategies to population fitness are yet to be understood clearly. Genus Zingiber belonging to the pan-tropic family Zingiberaceae represents a good system to study contributions of different breeding behavior on genetic diversity and population fitness, as this genus comprises species with contrasting breeding systems. In this study, we analyzed breeding behavior, amplified fragment length polymorphism diversity and response to the soft-rot pathogen Pythium aphanidermatum in 18 natural populations of three wild Zingiber spp.: Z. neesanum, Z. nimmonii, and Z. zerumbet, together with the obligately asexual cultivated congener, ginger (Z. officinale). Ginger showed an exceptionally narrow genetic base, and adding to this, all the tested cultivars were uniformly susceptible to soft-rot. Concordant with the postulates of Muller’s ratchet, the background selection may be continuously pushing ginger into the ancestral state, rendering it inefficient in host-pathogen coevolution. Z. neesanum and Z. nimmonii populations were sexual and genetically diverse; however, contrary to Red Queen expectations, the populations were highly susceptible to soft-rot. Z. zerumbet showed a hemiclonal breeding behavior. The populations inhabiting forest understory were large and continuous, sexual and genetically

Genome-Wide Association Analysis Reveals Genetic Heterogeneity of Sjögren's Syndrome According to Ancestry.

Science.gov (United States)

Taylor, Kimberly E; Wong, Quenna; Levine, David M; McHugh, Caitlin; Laurie, Cathy; Doheny, Kimberly; Lam, Mi Y; Baer, Alan N; Challacombe, Stephen; Lanfranchi, Hector; Schiødt, Morten; Srinivasan, M; Umehara, Hisanori; Vivino, Frederick B; Zhao, Yan; Shiboski, Stephen C; Daniels, Troy E; Greenspan, John S; Shiboski, Caroline H; Criswell, Lindsey A

2017-06-01

The Sjögren's International Collaborative Clinical Alliance (SICCA) is an international data registry and biorepository derived from a multisite observational study of participants in whom genotyping was performed on the Omni2.5M platform and who had undergone deep phenotyping using common protocol-directed methods. The aim of this study was to examine the genetic etiology of Sjögren's syndrome (SS) across ancestry and disease subsets. We performed genome-wide association study analyses using SICCA subjects and external controls obtained from dbGaP data sets, one using all participants (1,405 cases, 1,622 SICCA controls, and 3,125 external controls), one using European participants (585, 966, and 580, respectively), and one using Asian participants (460, 224, and 901, respectively) with ancestry adjustments via principal components analyses. We also investigated whether subphenotype distributions differ by ethnicity, and whether this contributes to the heterogeneity of genetic associations. We observed significant associations in established regions of the major histocompatibility complex (MHC), IRF5, and STAT4 (P = 3 × 10 -42 , P = 3 × 10 -14 , and P = 9 × 10 -10 , respectively), and several novel suggestive regions (those with 2 or more associations at P ancestry (P = 4 × 10 -15 and P = 4 × 10 -5 , respectively), but that subphenotype differences did not explain most of the ancestry differences in genetic associations. Genetic associations with SS differ markedly according to ancestry; however, this is not explained by differences in subphenotypes. © 2017, The Authors. Arthritis & Rheumatology published by Wiley Periodicals, Inc. on behalf of American College of Rheumatology.

Initiation process of a thrust fault revealed by analog experiments

Science.gov (United States)

Yamada, Yasuhiro; Dotare, Tatsuya; Adam, Juergen; Hori, Takane; Sakaguchi, Hide

2016-04-01

We conducted 2D (cross-sectional) analog experiments with dry sand using a high resolution digital image correlation (DIC) technique to reveal initiation process of a thrust fault in detail, and identified a number of "weak shear bands" and minor uplift prior to the thrust initiation. The observations suggest that the process can be divided into three stages. Stage 1: characterized by a series of abrupt and short-lived weak shear bands at the location where the thrust will be generated later. Before initiation of the fault, the area to be the hanging wall starts to uplift. Stage 2: defined by the generation of the new thrust and its active displacement. The location of the new thrust seems to be constrained by its associated back-thrust, produced at the foot of the surface slope (by the previous thrust). The activity of the previous thrust turns to zero once the new thrust is generated, but the timing of these two events is not the same. Stage 3: characterized by a constant displacement along the (new) thrust. Similar minor shear bands can be seen in the toe area of the Nankai accretionary prism, SW Japan and we can correlate the along-strike variations in seismic profiles to the model results that show the characteristic features in each thrust development stage.

Genetic counselors' views and experiences with the clinical integration of genome sequencing.

Science.gov (United States)

Machini, Kalotina; Douglas, Jessica; Braxton, Alicia; Tsipis, Judith; Kramer, Kate

2014-08-01

In recent years, new sequencing technologies known as next generation sequencing (NGS) have provided scientists the ability to rapidly sequence all known coding as well as non-coding sequences in the human genome. As the two emerging approaches, whole exome (WES) and whole genome (WGS) sequencing, have started to be integrated in the clinical arena, we sought to survey health care professionals who are likely to be involved in the implementation process now and/or in the future (e.g., genetic counselors, geneticists and nurse practitioners). Two hundred twenty-one genetic counselors- one third of whom currently offer WES/WGS-participated in an anonymous online survey. The aims of the survey were first, to identify barriers to the implementation of WES/WGS, as perceived by survey participants; second, to provide the first systematic report of current practices regarding the integration of WES/WGS in clinic and/or research across the US and Canada and to illuminate the roles and challenges of genetic counselors participating in this process; and third to evaluate the impact of WES/WGS on patient care. Our results showed that genetic counseling practices with respect to WES/WGS are consistent with the criteria set forth in the ACMG 2012 policy statement, which highlights indications for testing, reporting, and pre/post test considerations. Our respondents described challenges related to offering WES/WGS, which included billing issues, the duration and content of the consent process, result interpretation and disclosure of incidental findings and variants of unknown significance. In addition, respondents indicated that specialty area (i.e., prenatal and cancer), lack of clinical utility of WES/WGS and concerns about interpretation of test results were factors that prevented them from offering this technology to patients. Finally, study participants identified the aspects of their professional training which have been most beneficial in aiding with the integration of

Molecular genetic features of polyploidization and aneuploidization reveal unique patterns for genome duplication in diploid Malus.

Directory of Open Access Journals (Sweden)

Michael J Considine

Full Text Available Polyploidization results in genome duplication and is an important step in evolution and speciation. The Malus genome confirmed that this genus was derived through auto-polyploidization, yet the genetic and meiotic mechanisms for polyploidization, particularly for aneuploidization, are unclear in this genus or other woody perennials. In fact the contribution of aneuploidization remains poorly understood throughout Plantae. We add to this knowledge by characterization of eupolyploidization and aneuploidization in 27,542 F₁ seedlings from seven diploid Malus populations using cytology and microsatellite markers. We provide the first evidence that aneuploidy exceeds eupolyploidy in the diploid crosses, suggesting aneuploidization is a leading cause of genome duplication. Gametes from diploid Malus had a unique combinational pattern; ova preserved euploidy exclusively, while spermatozoa presented both euploidy and aneuploidy. All non-reduced gametes were genetically heterozygous, indicating first-division restitution was the exclusive mode for Malus eupolyploidization and aneuploidization. Chromosome segregation pattern among aneuploids was non-uniform, however, certain chromosomes were associated for aneuploidization. This study is the first to provide molecular evidence for the contribution of heterozygous non-reduced gametes to fitness in polyploids and aneuploids. Aneuploidization can increase, while eupolyploidization may decrease genetic diversity in their newly established populations. Auto-triploidization is important for speciation in the extant Malus. The features of Malus polyploidization confer genetic stability and diversity, and present heterozygosity, heterosis and adaptability for evolutionary selection. A protocol using co-dominant markers was proposed for accelerating apple triploid breeding program. A path was postulated for evolution of numerically odd basic chromosomes. The model for Malus derivation was considerably revised

Molecular genetic features of polyploidization and aneuploidization reveal unique patterns for genome duplication in diploid Malus.

Science.gov (United States)

Considine, Michael J; Wan, Yizhen; D'Antuono, Mario F; Zhou, Qian; Han, Mingyu; Gao, Hua; Wang, Man

2012-01-01

Polyploidization results in genome duplication and is an important step in evolution and speciation. The Malus genome confirmed that this genus was derived through auto-polyploidization, yet the genetic and meiotic mechanisms for polyploidization, particularly for aneuploidization, are unclear in this genus or other woody perennials. In fact the contribution of aneuploidization remains poorly understood throughout Plantae. We add to this knowledge by characterization of eupolyploidization and aneuploidization in 27,542 F₁ seedlings from seven diploid Malus populations using cytology and microsatellite markers. We provide the first evidence that aneuploidy exceeds eupolyploidy in the diploid crosses, suggesting aneuploidization is a leading cause of genome duplication. Gametes from diploid Malus had a unique combinational pattern; ova preserved euploidy exclusively, while spermatozoa presented both euploidy and aneuploidy. All non-reduced gametes were genetically heterozygous, indicating first-division restitution was the exclusive mode for Malus eupolyploidization and aneuploidization. Chromosome segregation pattern among aneuploids was non-uniform, however, certain chromosomes were associated for aneuploidization. This study is the first to provide molecular evidence for the contribution of heterozygous non-reduced gametes to fitness in polyploids and aneuploids. Aneuploidization can increase, while eupolyploidization may decrease genetic diversity in their newly established populations. Auto-triploidization is important for speciation in the extant Malus. The features of Malus polyploidization confer genetic stability and diversity, and present heterozygosity, heterosis and adaptability for evolutionary selection. A protocol using co-dominant markers was proposed for accelerating apple triploid breeding program. A path was postulated for evolution of numerically odd basic chromosomes. The model for Malus derivation was considerably revised. Impacts of

Time-Series Analyses of Transcriptomes and Proteomes Reveal Molecular Networks Underlying Oil Accumulation in Canola.

Science.gov (United States)

Wan, Huafang; Cui, Yixin; Ding, Yijuan; Mei, Jiaqin; Dong, Hongli; Zhang, Wenxin; Wu, Shiqi; Liang, Ying; Zhang, Chunyu; Li, Jiana; Xiong, Qing; Qian, Wei

2016-01-01

Understanding the regulation of lipid metabolism is vital for genetic engineering of canola ( Brassica napus L.) to increase oil yield or modify oil composition. We conducted time-series analyses of transcriptomes and proteomes to uncover the molecular networks associated with oil accumulation and dynamic changes in these networks in canola. The expression levels of genes and proteins were measured at 2, 4, 6, and 8 weeks after pollination (WAP). Our results show that the biosynthesis of fatty acids is a dominant cellular process from 2 to 6 WAP, while the degradation mainly happens after 6 WAP. We found that genes in almost every node of fatty acid synthesis pathway were significantly up-regulated during oil accumulation. Moreover, significant expression changes of two genes, acetyl-CoA carboxylase and acyl-ACP desaturase, were detected on both transcriptomic and proteomic levels. We confirmed the temporal expression patterns revealed by the transcriptomic analyses using quantitative real-time PCR experiments. The gene set association analysis show that the biosynthesis of fatty acids and unsaturated fatty acids are the most significant biological processes from 2-4 WAP and 4-6 WAP, respectively, which is consistent with the results of time-series analyses. These results not only provide insight into the mechanisms underlying lipid metabolism, but also reveal novel candidate genes that are worth further investigation for their values in the genetic engineering of canola.

Nuclear genetic diversity in human lice (Pediculus humanus reveals continental differences and high inbreeding among worldwide populations.

Directory of Open Access Journals (Sweden)

Marina S Ascunce

Full Text Available Understanding the evolution of parasites is important to both basic and applied evolutionary biology. Knowledge of the genetic structure of parasite populations is critical for our ability to predict how an infection can spread through a host population and for the design of effective control methods. However, very little is known about the genetic structure of most human parasites, including the human louse (Pediculus humanus. This species is composed of two ecotypes: the head louse (Pediculus humanus capitis De Geer, and the clothing (body louse (Pediculus humanus humanus Linnaeus. Hundreds of millions of head louse infestations affect children every year, and this number is on the rise, in part because of increased resistance to insecticides. Clothing lice affect mostly homeless and refugee-camp populations and although they are less prevalent than head lice, the medical consequences are more severe because they vector deadly bacterial pathogens. In this study we present the first assessment of the genetic structure of human louse populations by analyzing the nuclear genetic variation at 15 newly developed microsatellite loci in 93 human lice from 11 sites in four world regions. Both ecotypes showed heterozygote deficits relative to Hardy-Weinberg equilibrium and high inbreeding values, an expected pattern given their parasitic life history. Bayesian clustering analyses assigned lice to four distinct genetic clusters that were geographically structured. The low levels of gene flow among louse populations suggested that the evolution of insecticide resistance in lice would most likely be affected by local selection pressures, underscoring the importance of tailoring control strategies to population-specific genetic makeup and evolutionary history. Our panel of microsatellite markers provides powerful data to investigate not only ecological and evolutionary processes in lice, but also those in their human hosts because of the long

Genetic variability of garlic accessions as revealed by agro-morphological traits evaluated under different environments.

Science.gov (United States)

Hoogerheide, E S S; Azevedo Filho, J A; Vencovsky, R; Zucchi, M I; Zago, B W; Pinheiro, J B

2017-05-31

The cultivated garlic (Allium sativum L.) displays a wide phenotypic diversity, which is derived from natural mutations and phenotypic plasticity, due to dependence on soil type, moisture, latitude, altitude and cultural practices, leading to a large number of cultivars. This study aimed to evaluate the genetic variability shown by 63 garlic accessions belonging to Instituto Agronômico de Campinas and the Escola Superior de Agricultura "Luiz de Queiroz" germplasm collections. We evaluated ten quantitative characters in experimental trials conducted under two localities of the State of São Paulo: Monte Alegre do Sul and Piracicaba, during the agricultural year of 2007, in a randomized blocks design with five replications. The Mahalanobis distance was used to measure genetic dissimilarities. The UPGMA method and Tocher's method were used as clustering procedures. Results indicated significant variation among accessions (P < 0.01) for all evaluated characters, except for the percentage of secondary bulb growth in MAS, indicating the existence of genetic variation for bulb production, and germplasm evaluation considering different environments is more reliable for the characterization of the genotypic variability among garlic accessions, since it diminishes the environmental effects in the clustering of genotypes.

eQTL Networks Reveal Complex Genetic Architecture in the Immature Soybean Seed

Directory of Open Access Journals (Sweden)

Yung-Tsi Bolon

2014-03-01

Full Text Available The complex network of regulatory factors and interactions involved in transcriptional regulation within the seed is not well understood. To evaluate gene expression regulation in the immature seed, we utilized a genetical genomics approach on a soybean [ (L. Merr.] recombinant inbred line (RIL population and produced a genome-wide expression quantitative trait loci (eQTL dataset. The validity of the dataset was confirmed by mapping the eQTL hotspot for flavonoid biosynthesis-related genes to a region containing repeats of chalcone synthase (CHS genes known to correspond to the soybean inhibitor locus that regulates seed color. We then identified eQTL for genes with seed-specific expression and discovered striking eQTL hotspots at distinct genomic intervals on chromosomes (Chr 20, 7, and 13. The main eQTL hotspot for transcriptional regulation of fatty acid biosynthesis genes also coincided with regulation of oleosin genes. Transcriptional upregulation of genesets from eQTL with opposite allelic effects were also found. Gene–eQTL networks were constructed and candidate regulatory genes were identified from these three key loci specific to seed expression and enriched in genes involved in seed oil accumulation. Our data provides new insight into the complex nature of gene networks in the immature soybean seed and the genetic architecture that contributes to seed development.

The loss of genetic diversity in the Chinese paddlefish (Psephurus ...

Indian Academy of Sciences (India)

Unknown

The loss of genetic diversity in the Chinese paddlefish. (Psephurus gladius Martens) as revealed by DNA fingerprinting. XUE-CHANG WU*. College of Life Sciences and the Key Laboratory of Conservation Genetics and Reproductive Biology for Endangered. Wild Animals of the Ministry of Education, Zhejiang University, ...

Shared activity patterns arising at genetic susceptibility loci reveal underlying genomic and cellular architecture of human disease

DEFF Research Database (Denmark)

Baillie, J Kenneth; Bretherick, Andrew; Haley, Christopher S

2018-01-01

Genetic variants underlying complex traits, including disease susceptibility, are enriched within the transcriptional regulatory elements, promoters and enhancers. There is emerging evidence that regulatory elements associated with particular traits or diseases share similar patterns...... the regulation of the OCT1 cation transporter and genetic variants underlying circulating cholesterol levels. NDA strongly implicates particular cell types and tissues in disease pathogenesis. For example, distinct groupings of disease-associated regulatory regions implicate two distinct biological processes...... in the pathogenesis of ulcerative colitis; a further two separate processes are implicated in Crohn's disease. Thus, our functional analysis of genetic predisposition to disease defines new distinct disease endotypes. We predict that patients with a preponderance of susceptibility variants in each group are likely...

Ancient DNA Reveals That the Genetic Structure of the Northern Han Chinese Was Shaped Prior to 3,000 Years Ago

Science.gov (United States)

Zhang, Quan-Chao; Li, Hong-Jie; Cui, Ying-Qiu; Xu, Zhi; Jin, Li; Zhou, Hui; Zhu, Hong

2015-01-01

The Han Chinese are the largest ethnic group in the world, and their origins, development, and expansion are complex. Many genetic studies have shown that Han Chinese can be divided into two distinct groups: northern Han Chinese and southern Han Chinese. The genetic history of the southern Han Chinese has been well studied. However, the genetic history of the northern Han Chinese is still obscure. In order to gain insight into the genetic history of the northern Han Chinese, 89 human remains were sampled from the Hengbei site which is located in the Central Plain and dates back to a key transitional period during the rise of the Han Chinese (approximately 3,000 years ago). We used 64 authentic mtDNA data obtained in this study, 27 Y chromosome SNP data profiles from previously studied Hengbei samples, and genetic datasets of the current Chinese populations and two ancient northern Chinese populations to analyze the relationship between the ancient people of Hengbei and present-day northern Han Chinese. We used a wide range of population genetic analyses, including principal component analyses, shared mtDNA haplotype analyses, and geographic mapping of maternal genetic distances. The results show that the ancient people of Hengbei bore a strong genetic resemblance to present-day northern Han Chinese and were genetically distinct from other present-day Chinese populations and two ancient populations. These findings suggest that the genetic structure of northern Han Chinese was already shaped 3,000 years ago in the Central Plain area. PMID:25938511

Comparative linkage meta-analysis reveals regionally-distinct, disparate genetic architectures: application to bipolar disorder and schizophrenia.

Directory of Open Access Journals (Sweden)

Brady Tang

2011-04-01

Full Text Available New high-throughput, population-based methods and next-generation sequencing capabilities hold great promise in the quest for common and rare variant discovery and in the search for "missing heritability." However, the optimal analytic strategies for approaching such data are still actively debated, representing the latest rate-limiting step in genetic progress. Since it is likely a majority of common variants of modest effect have been identified through the application of tagSNP-based microarray platforms (i.e., GWAS, alternative approaches robust to detection of low-frequency (1-5% MAF and rare (<1% variants are of great importance. Of direct relevance, we have available an accumulated wealth of linkage data collected through traditional genetic methods over several decades, the full value of which has not been exhausted. To that end, we compare results from two different linkage meta-analysis methods--GSMA and MSP--applied to the same set of 13 bipolar disorder and 16 schizophrenia GWLS datasets. Interestingly, we find that the two methods implicate distinct, largely non-overlapping, genomic regions. Furthermore, based on the statistical methods themselves and our contextualization of these results within the larger genetic literatures, our findings suggest, for each disorder, distinct genetic architectures may reside within disparate genomic regions. Thus, comparative linkage meta-analysis (CLMA may be used to optimize low-frequency and rare variant discovery in the modern genomic era.

Traffic experiment reveals the nature of car-following.

Science.gov (United States)

Jiang, Rui; Hu, Mao-Bin; Zhang, H M; Gao, Zi-You; Jia, Bin; Wu, Qing-Song; Wang, Bing; Yang, Ming

2014-01-01

As a typical self-driven many-particle system far from equilibrium, traffic flow exhibits diverse fascinating non-equilibrium phenomena, most of which are closely related to traffic flow stability and specifically the growth/dissipation pattern of disturbances. However, the traffic theories have been controversial due to a lack of precise traffic data. We have studied traffic flow from a new perspective by carrying out large-scale car-following experiment on an open road section, which overcomes the intrinsic deficiency of empirical observations. The experiment has shown clearly the nature of car-following, which runs against the traditional traffic flow theory. Simulations show that by removing the fundamental notion in the traditional car-following models and allowing the traffic state to span a two-dimensional region in velocity-spacing plane, the growth pattern of disturbances has changed qualitatively and becomes qualitatively or even quantitatively in consistent with that observed in the experiment.

Genetic testing in the workplace: the employer's coin toss.

Science.gov (United States)

French, Samantha

2002-09-05

A toss of the coin by the modern-day employer reveals two options regarding genetic testing in the workplace. The employer may choose to take advantage of increasingly precise, available, and affordable genetic testing in order to ascertain the genetic characteristics--and deficiencies--of its employees. This outcome exposes the employer to a vast array of potential litigation and liability relating to the Americans with Disabilities Act, the Fourth Amendment, Title VII of the Civil Rights Act, and state legislation designed to protect genetic privacy. Alternatively, the employer may neglect to indulge in this trend of genetic testing and may face liability for employer negligence, violations of federal legislation such as OSHA regulations, and increased costs associated with insuring the health of genetically endangered employees. In the rapidly developing universe of genetic intelligence, the employer is faced with a staggering dilemma.

African American Women’s Limited Knowledge and Experiences with Genetic Counseling for Hereditary Breast Cancer

Science.gov (United States)

Sheppard, Vanessa B.; Graves, Kristi D.; Christopher, Juleen; Hurtado-de-Mendoza, Alejandra; Talley, Costellia; Williams, Karen Patricia

2014-01-01

Genetic counseling and testing for hereditary breast cancer have the potential benefit of early detection and early interventions in African American women. However, African American women have low use of these services compared to White women. We conducted two focus groups with African American women diagnosed with breast cancer (affected group, n=13) and women with at least one first-degree relative with breast/ovarian cancer (unaffected group, n= 8). A content analysis approach was employed to analyze interview data. Breast cancer survivors had more knowledge about genetic counseling and testing than participants who were unaffected with cancer. However, knowledge about genetic counseling was limited in both groups. Barriers to pursuing genetic counseling and testing included poor understanding of the genetic counseling and testing process, fear of carrying the mutation, concerns about discrimination, and cost. Motivators to participate in genetic counseling and testing included desire to help family members, insurance coverage, and potential of benefiting the larger African American community. Education efforts are needed to increase genetic counseling and testing awareness in the African American community. PMID:24186304

Molecular genetic differentiation in earthworms inhabiting a heterogeneous Pb-polluted landscape

Energy Technology Data Exchange (ETDEWEB)

Andre, J., E-mail: Andrej@cardiff.ac.u [Cardiff School of Biosciences, Cardiff University, BIOSI 1, Museum Avenue, Cardiff CF10 3TL (United Kingdom); Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom); King, R.A. [Cardiff School of Biosciences, Cardiff University, BIOSI 1, Museum Avenue, Cardiff CF10 3TL (United Kingdom); Stuerzenbaum, S.R. [King' s College London, School of Biomedical and Health Sciences, Pharmaceutical Sciences Division, London SE1 9NH (United Kingdom); Kille, P. [Cardiff School of Biosciences, Cardiff University, BIOSI 1, Museum Avenue, Cardiff CF10 3TL (United Kingdom); Hodson, M.E. [Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom); Morgan, A.J. [Cardiff School of Biosciences, Cardiff University, BIOSI 1, Museum Avenue, Cardiff CF10 3TL (United Kingdom)

2010-03-15

A Pb-mine site situated on acidic soil, but comprising of Ca-enriched islands around derelict buildings was used to study the spatial pattern of genetic diversity in Lumbricus rubellus. Two distinct genetic lineages ('A' and 'B'), differentiated at both the mitochondrial (mtDNA COII) and nuclear level (AFLPs) were revealed with a mean inter-lineage mtDNA sequence divergence of approximately 13%, indicative of a cryptic species complex. AFLP analysis indicates that lineage A individuals within one central 'ecological island' site are uniquely clustered, with little genetic overlap with lineage A individuals at the two peripheral sites. FTIR microspectroscopy of Pb-sequestering chloragocytes revealed different phosphate profiles in residents of adjacent acidic and calcareous islands. Bioinformatics found over-representation of Ca pathway genes in EST{sub Pb} libraries. Subsequent sequencing of a Ca-transport gene, SERCA, revealed mutations in the protein's cytosolic domain. We recommend the mandatory genotyping of all individuals prior to field-based ecotoxicological assays, particularly those using discriminating genomic technologies. - Landscapes punctuated by Pb-polluted islands have engendered local genetic differentiation in resident earthworms.

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Status of research on Drosophila ananassae at global level ... and domestic species endowed with several unusual genetic features, is noteworthy. ... Bibliography on this species from different countries worldwide reveals that maximum ...

Genetic variation among isolates of Sarcocystis neurona, the agent of protozoal myeloencephalitis, as revealed by amplified fragment length polymorphism markers.

Science.gov (United States)

Elsheikha, H M; Schott, H C; Mansfield, L S

2006-06-01

Sarcocystis neurona causes serious neurological disease in horses and other vertebrates in the Americas. Based on epidemiological data, this parasite has recently emerged. Here, the genetic diversity of Sarcocystis neurona was evaluated using the amplified fragment length polymorphism (AFLP) method. Fifteen S. neurona taxa from different regions collected over the last 10 years were used; six isolates were from clinically diseased horses, eight isolates were from wild-caught opossums (Didelphis virginiana), and one isolate was from a cowbird (Molothrus ater). Additionally, four outgroup taxa were also fingerprinted. Nine primer pairs were used to generate AFLP patterns, with a total number of amplified fragments ranging from 30 to 60, depending on the isolate and primers tested. Based on the presence/absence of amplified AFLP fragments and pairwise similarity values, all the S. neurona isolates tested were clustered in one monophyletic group. No significant correlation could be found between genomic similarity and host origin of the S. neurona isolates. AFLP revealed significant intraspecific genetic variations, and S. neurona appeared as a highly variable species. Furthermore, linkage disequilibrium analysis suggested that S. neurona populations within Michigan have an intermediate type of population structure that includes characteristics of both clonal and panamictic population structures. AFLP is a reliable molecular technique that has provided one of the most informative approaches to ascertain phylogenetic relationships in S. neurona and its closest relatives, allowing them to be clustered by relative similarity using band matching and unweighted pair group method with arithmetic mean analysis, which may be applicable to other related protozoal species.

Genetic and non-genetic factors affecting rabbit doe sexual receptivity as estimated from one generation of divergent selection

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M. Theau.Clément

2015-09-01

Full Text Available Sexual receptivity of rabbit does at insemination greatly influences fertility and is generally induced by hormones or techniques known as “biostimulation”. Searching for more sustainable farming systems, an original alternative would be to utilise the genetic pathway to increase the does’receptivity. The purpose of the present study was to identify genetic and non-genetic factors that influence rabbit doe sexual receptivity, in the context of a divergent selection experiment over 1 generation. The experiment spanned 2 generations: the founder generation (G0 consisting of 140 rabbit does, and the G1 generation comprising 2 divergently selected lines (L and H lines with 70 does each and 2 successive batches from each generation. The selection rate of the G0 females to form the G1 lines was 24/140. The selection tests consisted of 16 to 18 successive receptivity tests at the rate of 3 tests per week. On the basis of 4716 tests from 275 females, the average receptivity was 56.6±48.2%. A batch effect and a test operator effect were revealed. The contribution of females to the total variance was 20.0%, whereas that of bucks was only 1.1%. Throughout the experiment, 18.2% of does expressed a low receptivity (< 34%, 50.7% a medium one and 33.1% a high one (>66%. Some does were frequently receptive, whereas others were rarely receptive. The repeatability of sexual receptivity was approximately 20%. The results confirmed the high variability of sexual receptivity of non-lactating rabbit does maintained without any biostimulation or hormonal treatment. A lack of selection response on receptivity was observed. Accordingly, the heritability of receptivity was estimated at 0.01±0.02 from an animal model and at 0.02±0.03 from a  sire and dam model. The heritability of the average receptivity of a doe was calculated as 0.04. In agreement with the low estimated heritability, the heritability determined was no different from zero

Genome-wide association study of borderline personality disorder reveals genetic overlap with bipolar disorder, major depression and schizophrenia

DEFF Research Database (Denmark)

Witt, S H; Streit, F; Jungkunz, M

2017-01-01

Borderline personality disorder (BOR) is determined by environmental and genetic factors, and characterized by affective instability and impulsivity, diagnostic symptoms also observed in manic phases of bipolar disorder (BIP). Up to 20% of BIP patients show comorbidity with BOR. This report...... describes the first case-control genome-wide association study (GWAS) of BOR, performed in one of the largest BOR patient samples worldwide. The focus of our analysis was (i) to detect genes and gene sets involved in BOR and (ii) to investigate the genetic overlap with BIP. As there is considerable genetic...... overlap between BIP, major depression (MDD) and schizophrenia (SCZ) and a high comorbidity of BOR and MDD, we also analyzed the genetic overlap of BOR with SCZ and MDD. GWAS, gene-based tests and gene-set analyses were performed in 998 BOR patients and 1545 controls. Linkage disequilibrium score...

Ancient DNA from South-East Europe Reveals Different Events during Early and Middle Neolithic Influencing the European Genetic Heritage.

Science.gov (United States)

Hervella, Montserrat; Rotea, Mihai; Izagirre, Neskuts; Constantinescu, Mihai; Alonso, Santos; Ioana, Mihai; Lazăr, Cătălin; Ridiche, Florin; Soficaru, Andrei Dorian; Netea, Mihai G; de-la-Rua, Concepcion

2015-01-01

The importance of the process of Neolithization for the genetic make-up of European populations has been hotly debated, with shifting hypotheses from a demic diffusion (DD) to a cultural diffusion (CD) model. In this regard, ancient DNA data from the Balkan Peninsula, which is an important source of information to assess the process of Neolithization in Europe, is however missing. In the present study we show genetic information on ancient populations of the South-East of Europe. We assessed mtDNA from ten sites from the current territory of Romania, spanning a time-period from the Early Neolithic to the Late Bronze Age. mtDNA data from Early Neolithic farmers of the Starčevo Criş culture in Romania (Cârcea, Gura Baciului and Negrileşti sites), confirm their genetic relationship with those of the LBK culture (Linienbandkeramik Kultur) in Central Europe, and they show little genetic continuity with modern European populations. On the other hand, populations of the Middle-Late Neolithic (Boian, Zau and Gumelniţa cultures), supposedly a second wave of Neolithic migration from Anatolia, had a much stronger effect on the genetic heritage of the European populations. In contrast, we find a smaller contribution of Late Bronze Age migrations to the genetic composition of Europeans. Based on these findings, we propose that permeation of mtDNA lineages from a second wave of Middle-Late Neolithic migration from North-West Anatolia into the Balkan Peninsula and Central Europe represent an important contribution to the genetic shift between Early and Late Neolithic populations in Europe, and consequently to the genetic make-up of modern European populations.

Variable-number-of-tandem-repeats analysis of genetic diversity in Pasteuria ramosa.

Science.gov (United States)

Mouton, L; Ebert, D

2008-05-01

Variable-number-of-tandem-repeats (VNTR) markers are increasingly being used in population genetic studies of bacteria. They were recently developed for Pasteuria ramosa, an endobacterium that infects Daphnia species. In the present study, we genotyped P. ramosa in 18 infected hosts from the United Kingdom, Belgium, and two lakes in the United States using seven VNTR markers. Two Daphnia species were collected: D. magna and D. dentifera. Six loci showed length polymorphism, with as many as five alleles identified for a single locus. Similarity coefficient calculations showed that the extent of genetic variation between pairs of isolates within populations differed according to the population, but it was always less than the genetic distances among populations. Analysis of the genetic distances performed using principal component analysis revealed strong clustering by location of origin, but not by host Daphnia species. Our study demonstrated that the VNTR markers available for P. ramosa are informative in revealing genetic differences within and among populations and may therefore become an important tool for providing detailed analysis of population genetics and epidemiology.

Mouse to human comparative genetics reveals a novel immunoglobulin E-controlling locus on Hsa8q12

Czech Academy of Sciences Publication Activity Database

Gusareva, Elena; Havelková, Helena; Blažková, Hana; Kosařová, Marcela; Kučera, P.; Král, V.; Salyakina, D.; Mulller-Myhsok, b.; Lipoldová, Marie

2009-01-01

Roč. 61, č. 1 (2009), s. 15-25 ISSN 0093-7711 R&D Projects: GA ČR GA310/06/1745; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z50520514 Keywords : atopy * specific IgE * genetic loci * mouse-human homology * Czech population * 8q12 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.988, year: 2009

Host Genetics: Fine-Tuning Innate Signaling

OpenAIRE

Fellay, Jacques; Goldstein, David B.

2007-01-01

A polymorphism modulating innate immunity signal transduction has recently been shown to influence human susceptibility to many different infections, providing one more indication of the potential of host genetics to reveal physiological pathways and mechanisms that influence resistance to infectious diseases.

Genetic mapping in mice reveals the involvement of Pcdh9 in long-term social and object recognition and sensorimotor development

NARCIS (Netherlands)

Bruining, Hilgo; Matsui, Asuka; Oguro-Ando, Asami; Kahn, René S.; Van'T Spijker, Heleen M.; Akkermans, Guus; Stiedl, Oliver; Van Engeland, Herman; Koopmans, Bastijn; Van Lith, Hein A.; Oppelaar, Hugo; Tieland, Liselotte; Nonkes, Lourens J.; Yagi, Takeshi; Kaneko, Ryosuke; Burbach, J. Peter H; Yamamoto, Nobuhiko; Kas, Martien J.

2015-01-01

Background Quantitative genetic analysis of basic mouse behaviors is a powerful tool to identify novel genetic phenotypes contributing to neurobehavioral disorders. Here, we analyzed genetic contributions to single-trial, long-term social and nonsocial recognition and subsequently studied the

Genetic Mapping in Mice Reveals the Involvement of Pcdh9 in Long-Term Social and Object Recognition and Sensorimotor Development

NARCIS (Netherlands)

Bruining, Hilgo; Matsui, Asuka; Oguro-Ando, Asami; Kahn, René S; Van't Spijker, Heleen M; Akkermans, Guus; Stiedl, Oliver; van Engeland, Herman; Koopmans, Bastijn; van Lith, Hein A; Oppelaar, Hugo; Tieland, Liselotte; Nonkes, Lourens J; Yagi, Takeshi; Kaneko, Ryosuke; Burbach, J Peter H; Yamamoto, Nobuhiko; Kas, Martien J

2015-01-01

BACKGROUND: Quantitative genetic analysis of basic mouse behaviors is a powerful tool to identify novel genetic phenotypes contributing to neurobehavioral disorders. Here, we analyzed genetic contributions to single-trial, long-term social and nonsocial recognition and subsequently studied the

Testing the structure of a hydrological model using Genetic Programming

Science.gov (United States)

Selle, Benny; Muttil, Nitin

2011-01-01

SummaryGenetic Programming is able to systematically explore many alternative model structures of different complexity from available input and response data. We hypothesised that Genetic Programming can be used to test the structure of hydrological models and to identify dominant processes in hydrological systems. To test this, Genetic Programming was used to analyse a data set from a lysimeter experiment in southeastern Australia. The lysimeter experiment was conducted to quantify the deep percolation response under surface irrigated pasture to different soil types, watertable depths and water ponding times during surface irrigation. Using Genetic Programming, a simple model of deep percolation was recurrently evolved in multiple Genetic Programming runs. This simple and interpretable model supported the dominant process contributing to deep percolation represented in a conceptual model that was published earlier. Thus, this study shows that Genetic Programming can be used to evaluate the structure of hydrological models and to gain insight about the dominant processes in hydrological systems.

Molecular genetic diversity of Punica granatum L. (pomegranate) as revealed by microsatellite DNA markers

Science.gov (United States)

Pomegranate (Punica granatum L.) is one of the oldest known edible fruits and more and more it arouse interest of scientific community given its numerous biological activities. However, information about its genetic resources and characterization using reliable molecular markers are still scarce. In...

Genetic Alterations in Glioma

International Nuclear Information System (INIS)

Bralten, Linda B. C.; French, Pim J.

2011-01-01

Gliomas are the most common type of primary brain tumor and have a dismal prognosis. Understanding the genetic alterations that drive glioma formation and progression may help improve patient prognosis by identification of novel treatment targets. Recently, two major studies have performed in-depth mutation analysis of glioblastomas (the most common and aggressive subtype of glioma). This systematic approach revealed three major pathways that are affected in glioblastomas: The receptor tyrosine kinase signaling pathway, the TP53 pathway and the pRB pathway. Apart from frequent mutations in the IDH1/2 gene, much less is known about the causal genetic changes of grade II and III (anaplastic) gliomas. Exceptions include TP53 mutations and fusion genes involving the BRAF gene in astrocytic and pilocytic glioma subtypes, respectively. In this review, we provide an update on all common events involved in the initiation and/or progression across the different subtypes of glioma and provide future directions for research into the genetic changes

Testing the Structure of Hydrological Models using Genetic Programming

Science.gov (United States)

Selle, B.; Muttil, N.

2009-04-01

Genetic Programming is able to systematically explore many alternative model structures of different complexity from available input and response data. We hypothesised that genetic programming can be used to test the structure hydrological models and to identify dominant processes in hydrological systems. To test this, genetic programming was used to analyse a data set from a lysimeter experiment in southeastern Australia. The lysimeter experiment was conducted to quantify the deep percolation response under surface irrigated pasture to different soil types, water table depths and water ponding times during surface irrigation. Using genetic programming, a simple model of deep percolation was consistently evolved in multiple model runs. This simple and interpretable model confirmed the dominant process contributing to deep percolation represented in a conceptual model that was published earlier. Thus, this study shows that genetic programming can be used to evaluate the structure of hydrological models and to gain insight about the dominant processes in hydrological systems.

The Double Helix: Applying an Ethic of Care to the Duty to Warn Genetic Relatives of Genetic Information.

Science.gov (United States)

Weaver, Meaghann

2016-03-01

Genetic testing reveals information about a patient's health status and predictions about the patient's future wellness, while also potentially disclosing health information relevant to other family members. With the increasing availability and affordability of genetic testing and the integration of genetics into mainstream medicine, the importance of clarifying the scope of confidentiality and the rules regarding disclosure of genetic findings to genetic relatives is prime. The United Nations International Declaration on Human Genetic Data urges an appreciation for principles of equality, justice, solidarity and responsibility in the context of genetic testing, including a commitment to honoring the privacy and security of the person tested. Considering this global mandate and recent professional statements in the context of a legal amendment to patient privacy policies in Australia, a fresh scrutiny of the legal history of a physician's duty to warn is warranted. This article inquiries whether there may be anything ethically or socially amiss with a potential future recommendation for health professionals or patients to universally disclose particular cancer predisposition genetic diagnosis to genetic family members. While much of the discussion remains applicable to all genetic diagnosis, the article focuses on the practice of disclosure within the context of BRCA1/2 diagnosis. An 'ethic of care' interpretation of legal tradition and current practice will serve to reconcile law and medical policy on the issue of physician disclosure of genetic results to family members without patient consent. © 2015 John Wiley & Sons Ltd.

CuboCube: Student creation of a cancer genetics e-textbook using open-access software for social learning.

Directory of Open Access Journals (Sweden)

Puya Seid-Karbasi

2017-03-01

Full Text Available Student creation of educational materials has the capacity both to enhance learning and to decrease costs. Three successive honors-style classes of undergraduate students in a cancer genetics class worked with a new software system, CuboCube, to create an e-textbook. CuboCube is an open-source learning materials creation system designed to facilitate e-textbook development, with an ultimate goal of improving the social learning experience for students. Equipped with crowdsourcing capabilities, CuboCube provides intuitive tools for nontechnical and technical authors alike to create content together in a structured manner. The process of e-textbook development revealed both strengths and challenges of the approach, which can inform future efforts. Both the CuboCube platform and the Cancer Genetics E-textbook are freely available to the community.

Revealing the distinct habitat ranges and hybrid zone of genetic sub-populations within Pseudo-nitzschia pungens (Bacillariophyceae) in the West Pacific area.

Science.gov (United States)

Kim, Jin Ho; Wang, Pengbin; Park, Bum Soo; Kim, Joo-Hwan; Patidar, Shailesh Kumar; Han, Myung-Soo

2018-03-01

Genetic sub-populations (clades) of cosmopolitan marine diatom Pseudo-nitzschia pungens might have distinct habitats, and their hybrid zone is suspected in higher latitude area of the West Pacific area, however, it is still unrevealed because of technical difficulties and lack of evidences in natural environments. The aim of this study is to investigate the habitat characteristics of each clade of P. pungens on geographical distribution with the habitat temperature ranges of each clade and to reveal their hybrid zone in the West Pacific area. We employed the 137 number of nucleotide sequences of P. pungens and its sampling data (spatial and temporal scale) originated from the West Pacific area, and used field application of qPCR assay for intra-specific level of P. pungens. Only two genotypes, clade I and III, were identified in the West Pacific area. Clade I was distributed from 39 to 32.3°N, and clade III were from 1.4 to 34.4°N. The estimated habitat temperature for the clade I and clade III ranges were 8.1-26.9 °C and 24.2-31.2 °C, respectively. The latitudinal distributions and temperature ranges of each clade were significantly different. The qPCR assay employed, and results suggested that the hybrid zone for clade I and III has been observed in the southern Korean coasts, and clade III might be introduced from the Southern Pacific area. The cell abundances of clade III were strongly related with the higher seawater temperature and warm current force. This study has defined distinct habitat characteristics of genetically different sub-populations of P. pungens, and revealed its hybrid zone in natural environment for the first time. We also provided strong evidences about dispersion of the population of clade III to higher latitude in the West Pacific area. Copyright © 2018. Published by Elsevier B.V.

Genetic compatibility determines endophyte-grass combinations.

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Kari Saikkonen

Full Text Available Even highly mutually beneficial microbial-plant interactions, such as mycorrhizal- and rhizobial-plant exchanges, involve selfishness, cheating and power-struggles between the partners, which depending on prevailing selective pressures, lead to a continuum of interactions from antagonistic to mutualistic. Using manipulated grass-endophyte combinations in a five year common garden experiment, we show that grass genotypes and genetic mismatches constrain genetic combinations between the vertically (via host seeds transmitted endophytes and the out-crossing host, thereby reducing infections in established grass populations. Infections were lost in both grass tillers and seedlings in F(1 and F(2 generations, respectively. Experimental plants were collected as seeds from two different environments, i.e., meadows and nearby riverbanks. Endophyte-related benefits to the host included an increased number of inflorescences, but only in meadow plants and not until the last growing season of the experiment. Our results illustrate the importance of genetic host specificity and trans-generational maternal effects on the genetic structure of a host population, which act as destabilizing forces in endophyte-grass symbioses. We propose that (1 genetic mismatches may act as a buffering mechanism against highly competitive endophyte-grass genotype combinations threatening the biodiversity of grassland communities and (2 these mismatches should be acknowledged, particularly in breeding programmes aimed at harnessing systemic and heritable endophytes to improve the agriculturally valuable characteristics of cultivars.

Detection genetic variability of secale cereale L. by scot markers

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Lenka Petrovičová

2017-01-01

Full Text Available Rye (Secale cereale L. is our traditional cereal used for baking. The genetic variability of grown rye has been reduced by modern agronomic practices, which subsequently prompted the importance of search for species that could be useful as a gene pool for the improving of flour quality for human consumption or for other industrial uses. Therefore, the aim of this study was to detect genetic variability among the set of 45 rye genotypes using 8 SCoT markers. Amplification of genomic DNA of 45 genotypes, using SCoT analysis, yielded 114 fragments, with an average of 14.25 polymorphic fragments per primer. The most polymorphic primer was SCoT 36, where 21 polymorphic amplification products were detected. In contract the lowest polymorphic primer was SCoT 45 with 5 polymorphic products. Genetic polymorphism was characterized based on diversity index (DI, probability of identity (PI and polymorphic information content (PIC. The hierarchical cluster analysis showed that the rye genotypes were divided into 2 main clusters. One rye genotype Motto, origin from Poland formed a separate subcluster (1b. Subscluster 2a included only genotype Valtické (CSK. In this experiment, SCoT proved to be a rapid, reliable and practicable method for revealing of polymorphism in the rye cultivars. Normal 0 21 false false false EN-GB X-NONE X-NONE

Analyses between Reproductive Behaviour, Genetic Diversity and Pythium Responsiveness in Zingiber spp. reveal an adaptive significance for hemiclonality

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Geethu Elizabath Thomas

2016-12-01

Full Text Available AbstractMode of reproduction is generally considered to have long-range evolutionary implications on population survival. Because sexual reproduction produces genetically diverse genotypes, this mode of reproduction is predicted to positively influence the success potential of offspring in evolutionary arms race with parasites (Red queen whereas, without segregation and recombination, the obligate asexual multiplication may push a species into extinction due to the steady accumulation of deleterious mutations (Muller’s ratchet. However, the extent of linearity between reproductive strategies, genetic diversity and population fitness, and the contributions of different breeding strategies to population fitness are yet to be understood clearly. Genus Zingiber belonging to the pan-tropic family Zingiberaceae represents a good system to study contributions of different breeding behaviour on genetic diversity and population fitness, as this genus comprises species with contrasting breeding systems. In this study, we analyzed breeding behaviour, amplified fragment length polymorphism (AFLP diversity and response to the soft-rot pathogen Pythium aphanidermatum in 18 natural populations of three wild Zingiber spp.: Z. neesanum, Z. nimmonii and Z. zerumbet, together with the obligately asexual cultivated congener, ginger (Z. officinale. Ginger showed an exceptionally narrow genetic base, and adding to this, all the tested cultivars were uniformly susceptible to soft-rot. Concordant with the postulates of Muller’s ratchet, the background selection may be continuously pushing ginger into the ancestral state, rendering it inefficient in host-pathogen coevolution. Z. neesanum and Z. nimmonii populations were sexual and genetically diverse; however, contrary to Red Queen expectations, the populations were highly susceptible to soft-rot. Z. zerumbet showed a hemiclonal breeding behaviour. The populations inhabiting forest understory were large and

Ethical genetic research in Indigenous communities: challenges and successful approaches.

Science.gov (United States)

McWhirter, Rebekah E; Mununggirritj, Djapirri; Marika, Dipililnga; Dickinson, Joanne L; Condon, John R

2012-12-01

Indigenous populations, in common with all populations, stand to benefit from the potential of genetic research to lead to improvements in diagnostic and therapeutic tools for a wide range of complex diseases. However, many Indigenous communities, especially ones that are isolated, are not included in genetic research efforts. This situation is largely a consequence of the challenges of ethically conducting genetic research in Indigenous communities and compounded by Indigenous peoples' negative past experiences with genetic issues. To examine ways of addressing these challenges, we review one investigation of a cancer cluster in remote Aboriginal communities in Arnhem Land, Australia. Our experiences demonstrate that genetic research can be both ethically and successfully conducted with Indigenous communities by respecting the authority of the community, involving community members, and including regular community review throughout the research process. Copyright © 2012 Elsevier Ltd. All rights reserved.

Molecular Comparison and Evolutionary Analyses of VP1 Nucleotide Sequences of New African Human Enterovirus 71 Isolates Reveal a Wide Genetic Diversity

Science.gov (United States)

Nougairède, Antoine; Joffret, Marie-Line; Deshpande, Jagadish M.; Dubot-Pérès, Audrey; Héraud, Jean-Michel

2014-01-01

Most circulating strains of Human enterovirus 71 (EV-A71) have been classified primarily into three genogroups (A to C) on the basis of genetic divergence between the 1D gene, which encodes the VP1 capsid protein. The aim of the present study was to provide further insights into the diversity of the EV-A71 genogroups following the recent description of highly divergent isolates, in particular those from African countries, including Madagascar. We classified recent EV-A71 isolates by a large comparison of 3,346 VP1 nucleotidic sequences collected from GenBank. Analysis of genetic distances and phylogenetic investigations indicated that some recently-reported isolates did not fall into the genogroups A-C and clustered into three additional genogroups, including one Indian genogroup (genogroup D) and 2 African ones (E and F). Our Bayesian phylogenetic analysis provided consistent data showing that the genogroup D isolates share a recent common ancestor with the members of genogroup E, while the isolates of genogroup F evolved from a recent common ancestor shared with the members of the genogroup B. Our results reveal the wide diversity that exists among EV-A71 isolates and suggest that the number of circulating genogroups is probably underestimated, particularly in developing countries where EV-A71 epidemiology has been poorly studied. PMID:24598878

Population genetic analysis reveals barriers and corridors for gene flow within and among riparian populations of a rare plant.

Science.gov (United States)

Hevroy, Tanya H; Moody, Michael L; Krauss, Siegfried L

2018-02-01

Landscape features and life-history traits affect gene flow, migration and drift to impact on spatial genetic structure of species. Understanding this is important for managing genetic diversity of threatened species. This study assessed the spatial genetic structure of the rare riparian Grevillea sp. Cooljarloo (Proteaceae), which is restricted to a 20 km 2 region impacted by mining in the northern sandplains of the Southwest Australian Floristic Region, an international biodiversity hotspot. Within creek lines and floodplains, the distribution is largely continuous. Models of dispersal within riparian systems were assessed by spatial genetic analyses including population level partitioning of genetic variation and individual Bayesian clustering. High levels of genetic variation and weak isolation by distance within creek line and floodplain populations suggest large effective population sizes and strong connectivity, with little evidence for unidirectional gene flow as might be expected from hydrochory. Regional clustering of creek line populations and strong divergence among creek line populations suggest substantially lower levels of gene flow among creek lines than within creek lines. There was however a surprising amount of genetic admixture in floodplain populations, which could be explained by irregular flooding and/or movements by highly mobile nectar-feeding bird pollinators. Our results highlight that for conservation of rare riparian species, avoiding an impact to hydrodynamic processes, such as water tables and flooding dynamics, may be just as critical as avoiding direct impacts on the number of plants.

Cootie Genetics: Simulating Mendel's Experiments to Understand the Laws of Inheritance

Science.gov (United States)

Galloway, Katelyn; Anderson, Nadja

2014-01-01

"Cootie Genetics" is a hands-on, inquiry-based activity that enables students to learn the Mendelian laws of inheritance and gain an understanding of genetics principles and terminology. The activity begins with two true-breeding Cooties of the same species that exhibit five observable trait differences. Students observe the retention or…

Loss of genetic variability in a hatchery strain of Senegalese sole (Solea senegalensis revealed by sequence data of the mitochondrial DNA control region and microsatellite markers

Directory of Open Access Journals (Sweden)

Pablo Sánchez

2012-06-01

Full Text Available Comparisons of the levels of genetic variation within and between a hatchery F1 (FAR, n=116 of Senegalese sole, Solea senegalensis, and its wild donor population (ATL, n = 26, both native to the SW Atlantic coast of the Iberian peninsula, as well as between the wild donor population and a wild western Mediterranean sample (MED, n=18, were carried out by characterizing 412 base pairs of the nucleotide sequence of the mitochondrial DNA control region I, and six polymorphic microsatellite loci. FAR showed a substantial loss of genetic variability (haplotypic diversity, h=0.49±0.066; nucleotide diversity, π=0.006±0.004; private allelic richness, pAg=0.28 to its donor population ATL (h=0.69±0.114; π=0.009±0.006; pAg=1.21. Pairwise FST values of microsatellite data were highly significant (P < 0.0001 between FAR and ATL (0.053 and FAR and MED (0.055. The comparison of wild samples revealed higher values of genetic variability in MED than in ATL, but only with mtDNA CR-I sequence data (h=0.948±0.033; π=0.030±0.016. However, pairwise ΦST and FST values between ATL and MED were highly significant (P < 0.0001 with mtDNA CR-I (0.228 and with microsatellite data (0.095, respectively. While loss of genetic variability in FAR could be associated with the sampling error when the broodstock was established, the results of parental and sibship inference suggest that most of these losses can be attributed to a high variance in reproductive success among members of the broodstock, particularly among females.

Mammalian Genetics and Teratology Section

International Nuclear Information System (INIS)

Anon.

1980-01-01

The work of the Mammalian Genetics and Teratology Section includes research in mutagenesis, basic genetics, reproductive biology, and teratogenesis involving basic studies, method development, including exploration of the biological material, and testing. The basic studies make good use of the genetic material accumulated in mutagenesis experiments of various kinds, or of the findings of mutagenesis experiments themselves. In the latter category is the finding of a repair system in the fertilized egg. The genetics of repair competency or deficiency are now under study. A linear relationship between gene dosage and level of expression of an enzyme has been demonstrated. Opportunities for the study of gene action are provided by a number of X-autosome translocations which continue to be discovered in the course of mutagenesis experiments. In these rearrangements, X-chromosome inactivation extends to neighboring autosomal loci. Considerable progress has been made in developing the skeletal mutation system, which provides information on dominants that is highly useful for risk assessment. A sensitive-indicator test is now under development which will make the screening for skeletal mutations much faster and easier. Method development has also progressed on the in vivo somatic-mutation test now being widely used as an in vivo screen for mutagens. Another method developed here is the numerical sex-chromosome anomaly (NSA) test for nondisjunction. The NSA method is being used to explore the effects of female age on chromosome loss and nondisjunction. A model for estimating the misclassification error was experimentally established for the heritable translocation test. A rapid, easy, and sensitive in vivo screening test for teratogenesis was developed. An in vitro teratogenic prescreen being developed makes use of teratocarcinoma-derived cell lines

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

based STRUCTURE grouped all the accessions in two clusters with significant intermixing between populations, therefore, revealed that two genetically distinct gene pools are operating in the A. malaccensis populations cultivated in home gardens ...

Probing genetic diversity to characterize red rot resistance in sugarcane

Energy Technology Data Exchange (ETDEWEB)

Mumtaz, A S; Dure-e-Nayab,; Iqbal, M J; Shinwari, Z.K., E-mail: asmumtaz@qau.edu.pk

2011-10-15

Genetic diversity was assessed in a set of twelve sugarcane genotypes using Random Amplified Polymorphic DNA (RAPD). A total of thirty-two oligo-primers were employed, sixteen of them revealed amplification at 149 loci, out of which 136 were polymorphic. The genotype SPSG-26 showed the highest number of polymorphic loci, followed by CSSG-668 and HSF-242. Pairwise genetic similarity ranged from 67.2% to 83.3%. The UPGMA cluster analysis resolved most of the accessions in two groups. The clustering pattern did not place all resistant varieties in one or related group which depict diverse resistance source in the present set of sugarcane varieties. Ten primers revealed genotype specific bands among which four primers (K07, H02, K10 and F01) produced multiple genotype specific bands that aid genotype identification especially those with red rot resistance. The present study not only provided information on the genetic diversity among the genotypes but also revealed the potential of RAPD-PCR markers for genotype identification and therefore could be utilized in marker assisted selection for red rot resistance in sugarcane. (author)

Pantoea ananatis Genetic Diversity Analysis Reveals Limited Genomic Diversity as Well as Accessory Genes Correlated with Onion Pathogenicity

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Shaun P. Stice

2018-02-01

Full Text Available Pantoea ananatis is a member of the family Enterobacteriaceae and an enigmatic plant pathogen with a broad host range. Although P. ananatis strains can be aggressive on onion causing foliar necrosis and onion center rot, previous genomic analysis has shown that P. ananatis lacks the primary virulence secretion systems associated with other plant pathogens. We assessed a collection of fifty P. ananatis strains collected from Georgia over three decades to determine genetic factors that correlated with onion pathogenic potential. Previous genetic analysis studies have compared strains isolated from different hosts with varying diseases potential and isolation sources. Strains varied greatly in their pathogenic potential and aggressiveness on different cultivated Allium species like onion, leek, shallot, and chive. Using multi-locus sequence analysis (MLSA and repetitive extragenic palindrome repeat (rep-PCR techniques, we did not observe any correlation between onion pathogenic potential and genetic diversity among strains. Whole genome sequencing and pan-genomic analysis of a sub-set of 10 strains aided in the identification of a novel series of genetic regions, likely plasmid borne, and correlating with onion pathogenicity observed on single contigs of the genetic assemblies. We named these loci Onion Virulence Regions (OVR A-D. The OVR loci contain genes involved in redox regulation as well as pectate lyase and rhamnogalacturonase genes. Previous studies have not identified distinct genetic loci or plasmids correlating with onion foliar pathogenicity or pathogenicity on a single host pathosystem. The lack of focus on a single host system for this phytopathgenic disease necessitates the pan-genomic analysis performed in this study.

Analysis of genetically modified red-fleshed apples reveals effects on growth and consumer attributes

NARCIS (Netherlands)

Espley, R.V.; Bovy, A.G.; Bava, C.; Jaeger, S.R.; Tomes, S.; Norling, C.; Crawford, J.; Rowan, D.; McGhie, T.K.; Brendolise, C.; Putterill, J.; Schouten, H.J.; Hellens, R.P.; Allan, A.C.

2013-01-01

Consumers of whole foods, such as fruits, demand consistent high quality and seek varieties with enhanced health properties, convenience or novel taste. We have raised the polyphenolic content of apple by genetic engineering of the anthocyanin pathway using the apple transcription factor MYB10.

Update on Sporadic Colorectal Cancer Genetics.

Science.gov (United States)

Hardiman, Karin M

2018-05-01

Our understanding of the genetics of colorectal cancer has changed dramatically over recent years. Colorectal cancer can be classified in multiple different ways. Along with the advent of whole-exome sequencing, we have gained an understanding of the scale of the genetic changes found in sporadic colorectal cancer. We now know that there are multiple pathways that are commonly involved in the evolution of colorectal cancer including Wnt/β-catenin, RAS, EGFR, and PIK3 kinase. Another recent leap in our understanding of colorectal cancer genetics is the recognition that many, if not all tumors, are actually genetically heterogeneous within individual tumors and also between tumors. Recent research has revealed the prognostic and possibly therapeutic implications of various specific mutations, including specific mutations in BRAF and KRAS . There is increasing interest in the use of mutation testing for screening and surveillance through stool and circulating DNA testing. Recent advances in translational research in colorectal cancer genetics are dramatically changing our understanding of colorectal cancer and will likely change therapy and surveillance in the near future.

Genome Sequencing of Museum Specimens Reveals Rapid Changes in the Genetic Composition of Honey Bees in California.

Science.gov (United States)

Cridland, Julie M; Ramirez, Santiago R; Dean, Cheryl A; Sciligo, Amber; Tsutsui, Neil D

2018-02-01

The western honey bee, Apis mellifera, is an enormously influential pollinator in both natural and managed ecosystems. In North America, this species has been introduced numerous times from a variety of different source populations in Europe and Africa. Since then, feral populations have expanded into many different environments across their broad introduced range. Here, we used whole genome sequencing of historical museum specimens and newly collected modern populations from California (USA) to analyze the impact of demography and selection on introduced populations during the past 105 years. We find that populations from both northern and southern California exhibit pronounced genetic changes, but have changed in different ways. In northern populations, honey bees underwent a substantial shift from western European to eastern European ancestry since the 1960s, whereas southern populations are dominated by the introgression of Africanized genomes during the past two decades. Additionally, we identify an isolated island population that has experienced comparatively little change over a large time span. Fine-scale comparison of different populations and time points also revealed SNPs that differ in frequency, highlighting a number of genes that may be important for recent adaptations in these introduced populations. © The Author(s) 2018. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Genotyping of ancient Mycobacterium tuberculosis strains reveals historic genetic diversity.

Science.gov (United States)

Müller, Romy; Roberts, Charlotte A; Brown, Terence A

2014-04-22

The evolutionary history of the Mycobacterium tuberculosis complex (MTBC) has previously been studied by analysis of sequence diversity in extant strains, but not addressed by direct examination of strain genotypes in archaeological remains. Here, we use ancient DNA sequencing to type 11 single nucleotide polymorphisms and two large sequence polymorphisms in the MTBC strains present in 10 archaeological samples from skeletons from Britain and Europe dating to the second-nineteenth centuries AD. The results enable us to assign the strains to groupings and lineages recognized in the extant MTBC. We show that at least during the eighteenth-nineteenth centuries AD, strains of M. tuberculosis belonging to different genetic groups were present in Britain at the same time, possibly even at a single location, and we present evidence for a mixed infection in at least one individual. Our study shows that ancient DNA typing applied to multiple samples can provide sufficiently detailed information to contribute to both archaeological and evolutionary knowledge of the history of tuberculosis.

Comparative radiobiology of genetic loci of eukaryots as the basis of the general theory of mutations