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Sample records for chromosome 9p21 snps

  1. INK4/ARF Transcript Expression Is Associated with Chromosome 9p21 Variants Linked to Atherosclerosis

    OpenAIRE

    Liu, Yan; Sanoff, Hanna K.; Cho, Hyunsoon; Burd, Christin E.; Torrice, Chad; Mohlke, Karen L.; Ibrahim, Joseph G.; Thomas, Nancy E.; Sharpless, Norman E.

    2009-01-01

    Background Genome-wide association studies (GWAS) have linked common single nucleotide polymorphisms (SNPs) on chromosome 9p21 near the INK4/ARF (CDKN2A/B) tumor suppressor locus with risk of atherosclerotic diseases and type 2 diabetes mellitus. To explore the mechanism of this association, we investigated whether expression of proximate transcripts (p16INK4a , p15INK4b , ARF, ANRIL and MTAP) correlate with genotype of representative 9p21 SNPs. Methodology/Principal Findings We analyzed expr...

  2. INK4/ARF transcript expression is associated with chromosome 9p21 variants linked to atherosclerosis.

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    Yan Liu

    Full Text Available Genome-wide association studies (GWAS have linked common single nucleotide polymorphisms (SNPs on chromosome 9p21 near the INK4/ARF (CDKN2A/B tumor suppressor locus with risk of atherosclerotic diseases and type 2 diabetes mellitus. To explore the mechanism of this association, we investigated whether expression of proximate transcripts (p16(INK4a, p15(INK4b, ARF, ANRIL and MTAP correlate with genotype of representative 9p21 SNPs.We analyzed expression of 9p21 transcripts in purified peripheral blood T-cells (PBTL from 170 healthy donors. Samples were genotyped for six selected disease-related SNPs spanning the INK4/ARF locus. Correlations among these variables were determined by univariate and multivariate analysis. Significantly reduced expression of all INK4/ARF transcripts (p15(INK4b, p16(INK4a, ARF and ANRIL was found in PBTL of individuals harboring a common SNP (rs10757278 associated with increased risk of coronary artery disease, stroke and aortic aneurysm. Expression of MTAP was not influenced by rs10757278 genotype. No association of any these transcripts was noted with five other tested 9p21 SNPs.Genotypes of rs10757278 linked to increased risk of atherosclerotic diseases are also associated with decreased expression in PBTL of the INK4/ARF locus, which encodes three related anti-proliferative transcripts of known importance in tumor suppression and aging.

  3. Chromosome 9p21 and ABCA1 Genetic Variants and Their Interactions on Coronary Heart Disease and Ischemic Stroke in a Chinese Han Population

    OpenAIRE

    Xiao-Li Cao; Rui-Xing Yin; Feng Huang; Jin-Zhen Wu; Wu-Xian Chen

    2016-01-01

    The single nucleotide polymorphisms (SNPs) related to both coronary heart disease (CHD) and ischemic stroke (IS) in Chinese individuals have not been identified definitely. This study was developed to evaluate the genetic susceptibility to CHD and IS on the chromosome 9p21 and the adenosine triphosphate (ATP)-binding cassette transporter A1 genes (ABCA1) in a Chinese Han population. Genotypes of the rs1333040, rs1333042, rs4977574, rs2066715 and rs2740483 SNPs were determined in 1134 unrelate...

  4. Replication of the association of chromosomal region 9p21.3 with generalized aggressive periodontitis (gAgP using an independent case-control cohort

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    Ernst Florian D

    2010-08-01

    Full Text Available Abstract Background The human chromosomal region 9p21.3 has been shown to be strongly associated with Coronary Heart Disease (CHD in several Genome-wide Association Studies (GWAS. Recently, this region has also been shown to be associated with Aggressive Periodontitis (AgP, strengthening the hypothesis that the established epidemiological association between periodontitis and CHD is caused by a shared genetic background, in addition to common environmental and behavioural risk factors. However, the size of the analyzed cohorts in this primary analysis was small compared to other association studies on complex diseases. Using our own AgP cohort, we attempted to confirm the described associations for the chromosomal region 9p21.3. Methods We analyzed our cohort consisting of patients suffering from the most severe form of AgP, generalized AgP (gAgP (n = 130 and appropriate periodontally healthy control individuals (n = 339 by genotyping four tagging SNPs (rs2891168, rs1333042, rs1333048 and rs496892, located in the chromosomal region 9p21.3, that have been associated with AgP. Results The results confirmed significant associations between three of the four SNPs and gAgP. The combination of our results with those from the study which described this association for the first time in a meta-analysis of the four tagging SNPs produced clearly lower p-values compared with the results of each individual study. According to these results, the most plausible genetic model for the association of all four tested SNPs with gAgP seems to be the multiplicative one. Conclusion We positively replicated the finding of an association between the chromosomal region 9p21.3 and gAgP. This result strengthens support for the hypothesis that shared susceptibility genes within this chromosomal locus might be involved in the pathogenesis of both CHD and gAgP.

  5. Genetic Variant rs10757278 on Chromosome 9p21 Contributes to Myocardial Infarction Susceptibility

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    Guangyuan Chen

    2015-05-01

    Full Text Available Large-scale genome-wide association studies (GWAS have revealed that rs10757278 polymorphism (or its proxy rs1333049 on chromosome 9p21 is associated with myocardial infarction (MI susceptibility in individuals of Caucasian ancestry. Following studies in other populations investigated this association. However, some of these studies reported weak or no significant association. Here, we reevaluated this association using large-scale samples by searching PubMed and Google Scholar databases. Our results showed significant association between rs10757278 polymorphism and MI with p = 6.09 × 10−22, odds ratio (OR = 1.29, 95% confidence interval (CI 1.22–1.36 in pooled population. We further performed a subgroup analysis, and found significant association between rs10757278 polymorphism and MI in Asian and Caucasian populations. We identified that the association between rs10757278 polymorphism and MI did not vary substantially by excluding any one study. However, the heterogeneity among the selected studies varies substantially by excluding the study from the Pakistan population. We found even more significant association between rs10757278 polymorphism and MI in pooled population, p = 3.55 × 10−53, after excluding the study from the Pakistan population. In summary, previous studies reported weak or no significant association between rs10757278 polymorphism and MI. Interestingly, our analysis suggests that rs10757278 polymorphism is significantly associated with MI susceptibility by analyzing large-scale samples.

  6. Loss of chromosome 9p21 and decreased p16 expression correlate with malignant gastrointestinal stromal tumor

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To investigate loss of heterozygosity (LOH) of chromosome 9p21 and the prognostic relevance of p16 expression in gastrointestinal stromal tumor (GIST). METHODS: Fifty-one GIST patients (30 men and 21 women; median age 59 years; range 29-80 years) treated surgically within a 10-year period were grouped by aggressive behavior risk (17 with very low and low, 14 intermediate, and 20 high risk). GISTs were characterized immunohistochemically and evaluated for LOH of 9p21 by microsatellite analysis at D9S175...

  7. Functional analyses of coronary artery disease associated variation on chromosome 9p21 in vascular smooth muscle cells

    OpenAIRE

    Motterle, Anna; Pu, Xiangyuan; Wood, Harriet; Xiao, Qingzhong; Gor, Shivani; Liang Ng, Fu; Chan, Kenneth; Cross, Frank; Shohreh, Beski; Poston, Robin N.; Tucker, Arthur T.; Caulfield, Mark J; Ye, Shu

    2012-01-01

    Variation on chromosome 9p21 is associated with risk of coronary artery disease (CAD). This genomic region contains the CDKN2A and CDKN2B genes which encode the cell cycle regulators p16INK4a, p14ARF and p15INK4b and the ANRIL gene which encodes a non-coding RNA. Vascular smooth muscle cell (VSMC) proliferation plays an important role in the pathogenesis of atherosclerosis which causes CAD. We ascertained whether 9p21 genotype had an influence on CDKN2A/CDKN2B/ANRIL expression levels in VSMCs...

  8. A novel form of distal hereditary motor neuronopathy maps to chromosome 9p21.1-p12.

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    Christodoulou, K; Zamba, E; Tsingis, M; Mubaidin, A; Horani, K; Abu-Sheik, S; El-Khateeb, M; Kyriacou, K; Kyriakides, T; Al-Qudah, A K; Middleton, L

    2000-12-01

    Distal hereditary motor neuronopathies (dHMNs) form a heterogeneous group of rare disorders characterized by distal weakness and wasting in the limbs with no significant sensory involvement. Harding has classified dHMNs into seven categories based on clinical and genetic criteria. We report a novel form of autosomal recessive dHMN in 7 consanguineous families located in the Jerash region of Jordan. Onset of the disease is between 6 and 10 years of age and is characterized by weakness and atrophy of the lower limbs associated with pyramidal features. Within 2 years, symptoms progress to the upper limbs. Neurophysiological studies typically show normal conduction velocities, reduced compound motor action potential amplitudes, normal sensory nerve action potentials, and chronic neurogenic changes on needle electromyography. No significant abnormalities are seen on sural nerve biopsy. We call this novel form of dHMN Jerash hereditary motor neuronopathy. We studied the families at the molecular genetic level and mapped the Jerash hereditary motor neuronopathy gene to an approximately 0.54-cM region on chromosome 9p21.1-p12, flanked by microsatellite polymorphic marker loci D9S1845 and D9S1791. A maximum LOD score of 19.80 at theta = 0.001 was obtained between the disease and locus D9S1878. PMID:11117544

  9. A variant at chromosome 9p21 is associated with recurrent myocardial infarction and cardiac death after acute coronary syndrome:the GRACE Genetics Study

    OpenAIRE

    Buysschaert, Ian; Carruthers, Kathryn F.; Donald R Dunbar; Peuteman, Gilian; Rietzschel, Ernst; Belmans, Ann; Hedley, Ann; Meyer, Tim; Budaj, Andrzej; Werf, Frans; Lambrechts, Diether; Fox, Keith A. A.

    2010-01-01

    Recent genetic studies identified the rs1333049 variant on chromosome 9p21 as a major susceptibility locus for coronary artery disease and myocardial infarction (MI). Here, we evaluated whether this variant also contributes to recurrent MI or cardiac death following an acute coronary syndrome (ACS).

  10. Variants at the 9p21 locus and melanoma risk

    International Nuclear Information System (INIS)

    The influence of variants at the 9p21 locus on melanoma risk has been reported through investigation of CDKN2A variants through candidate gene approach as well as by genome wide association studies (GWAS). In the present study we genotyped, 25 SNPs that tag 273 variants on chromosome 9p21 in 837 melanoma cases and 1154 controls from Spain. Ten SNPs were selected based on previous associations, reported in GWAS, with either melanocytic nevi or melanoma risk or both. The other 15 SNPs were selected to fine map the CDKN2A gene region. All the 10 variants selected from the GWAS showed statistically significant association with melanoma risk. Statistically significant association with melanoma risk was also observed for the carriers of the variant T-allele of rs3088440 (540 C>T) at the 3’ UTR of CDKN2A gene with an OR 1.52 (95% CI 1.14-2.04). Interaction analysis between risk associated polymorphisms and previously genotyped MC1R variants, in the present study, did not show any statistically significant association. Statistical significant association was observed for the interaction between phototypes and the rs10811629 (located in intron 5 of MTAP). The strongest association was observed between the homozygous carrier of the A–allele and phototype II with an OR of 15.93 (95% CI 5.34-47.54). Our data confirmed the association of different variants at chromosome 9p21 with melanoma risk and we also found an association of a variant with skin phototypes

  11. SNP in the genome-wide association study hotspot on chromosome 9p21 confers susceptibility to diabetic nephropathy in type 1 diabetes

    DEFF Research Database (Denmark)

    Fagerholm, E; Ahlqvist, E; Forsblom, C; Sandholm, N; Syreeni, A; Parkkonen, M; McKnight, A J; Tarnow, Lise; Maxwell, A P; Parving, H-H; Groop, L; Groop, P-H

    2012-01-01

    Parental type 2 diabetes mellitus increases the risk of diabetic nephropathy in offspring with type 1 diabetes mellitus. Several single nucleotide polymorphisms (SNPs) that predispose to type 2 diabetes mellitus have recently been identified. It is, however, not known whether such SNPs also confer...

  12. Relationship between CAD risk genotype in the chromosome 9p21 locus and gene expression. Identification of eight new ANRIL splice variants.

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    Lasse Folkersen

    Full Text Available BACKGROUND: Several genome-wide association studies have recently linked a group of single nucleotide polymorphisms in the 9p21 region with cardiovascular disease. The molecular mechanisms of this link are not fully understood. We investigated five different expression microarray datasets in order to determine if the genotype had effect on expression of any gene transcript in aorta, mammary artery, carotid plaque and lymphoblastoid cells. METHODOLOGY/PRINCIPAL FINDINGS: After multiple testing correction, no genes were found to have relation to the rs2891168 risk genotype, either on a genome-wide scale or on a regional (8 MB scale. The neighbouring ANRIL gene was found to have eight novel transcript variants not previously known from literature and these varied by tissue type. We therefore performed a detailed probe-level analysis and found small stretches of significant relation to genotype but no consistent associations. In all investigated tissues we found an inverse correlation between ANRIL and the MTAP gene and a positive correlation between ANRIL and CDKN2A and CDKN2B. CONCLUSIONS/SIGNIFICANCE: Investigation of relation of the risk genotype to gene expression is complicated by the transcript complexity of the locus. With our investigation of a range of relevant tissue we wish to underscore the need for careful attention to the complexity of the alternative splicing issues in the region and its implications to the design of future gene expression studies.

  13. Allelic Imbalance in Regulation of ANRIL through Chromatin Interaction at 9p21 Endometriosis Risk Locus.

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    Nakaoka, Hirofumi; Gurumurthy, Aishwarya; Hayano, Takahide; Ahmadloo, Somayeh; Omer, Waleed H; Yoshihara, Kosuke; Yamamoto, Akihito; Kurose, Keisuke; Enomoto, Takayuki; Akira, Shigeo; Hosomichi, Kazuyoshi; Inoue, Ituro

    2016-04-01

    Genome-wide association studies (GWASs) have discovered numerous single nucleotide polymorphisms (SNPs) associated with human complex disorders. However, functional characterization of the disease-associated SNPs remains a formidable challenge. Here we explored regulatory mechanism of a SNP on chromosome 9p21 associated with endometriosis by leveraging "allele-specific" functional genomic approaches. By re-sequencing 1.29 Mb of 9p21 region and scrutinizing DNase-seq data from the ENCODE project, we prioritized rs17761446 as a candidate functional variant that was in perfect linkage disequilibrium with the original GWAS SNP (rs10965235) and located on DNase I hypersensitive site. Chromosome conformation capture followed by high-throughput sequencing revealed that the protective G allele of rs17761446 exerted stronger chromatin interaction with ANRIL promoter. We demonstrated that the protective allele exhibited preferential binding affinities to TCF7L2 and EP300 by bioinformatics and chromatin immunoprecipitation (ChIP) analyses. ChIP assays for histone H3 lysine 27 acetylation and RNA polymerase II reinforced the enhancer activity of the SNP site. The allele specific expression analysis for eutopic endometrial tissues and endometrial carcinoma cell lines showed that rs17761446 was a cis-regulatory variant where G allele was associated with increased ANRIL expression. Our work illuminates the allelic imbalances in a series of transcriptional regulation from factor binding to gene expression mediated by chromatin interaction underlie the molecular mechanism of 9p21 endometriosis risk locus. Functional genomics on common disease will unlock functional aspect of genotype-phenotype correlations in the post-GWAS stage. PMID:27055116

  14. Allelic Imbalance in Regulation of ANRIL through Chromatin Interaction at 9p21 Endometriosis Risk Locus

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    Nakaoka, Hirofumi; Gurumurthy, Aishwarya; Hayano, Takahide; Ahmadloo, Somayeh; Omer, Waleed H; Yoshihara, Kosuke; Yamamoto, Akihito; Kurose, Keisuke; Enomoto, Takayuki; Akira, Shigeo; Hosomichi, Kazuyoshi; Inoue, Ituro

    2016-01-01

    Genome-wide association studies (GWASs) have discovered numerous single nucleotide polymorphisms (SNPs) associated with human complex disorders. However, functional characterization of the disease-associated SNPs remains a formidable challenge. Here we explored regulatory mechanism of a SNP on chromosome 9p21 associated with endometriosis by leveraging “allele-specific” functional genomic approaches. By re-sequencing 1.29 Mb of 9p21 region and scrutinizing DNase-seq data from the ENCODE project, we prioritized rs17761446 as a candidate functional variant that was in perfect linkage disequilibrium with the original GWAS SNP (rs10965235) and located on DNase I hypersensitive site. Chromosome conformation capture followed by high-throughput sequencing revealed that the protective G allele of rs17761446 exerted stronger chromatin interaction with ANRIL promoter. We demonstrated that the protective allele exhibited preferential binding affinities to TCF7L2 and EP300 by bioinformatics and chromatin immunoprecipitation (ChIP) analyses. ChIP assays for histone H3 lysine 27 acetylation and RNA polymerase II reinforced the enhancer activity of the SNP site. The allele specific expression analysis for eutopic endometrial tissues and endometrial carcinoma cell lines showed that rs17761446 was a cis-regulatory variant where G allele was associated with increased ANRIL expression. Our work illuminates the allelic imbalances in a series of transcriptional regulation from factor binding to gene expression mediated by chromatin interaction underlie the molecular mechanism of 9p21 endometriosis risk locus. Functional genomics on common disease will unlock functional aspect of genotype-phenotype correlations in the post-GWAS stage. PMID:27055116

  15. Multiplex PCR and minisequencing of SNPs--a model with 35 Y chromosome SNPs

    DEFF Research Database (Denmark)

    Sanchez, Juan J; Børsting, Claus; Hallenberg, Charlotte;

    2003-01-01

    We have developed a robust single nucleotide polymorphism (SNPs) typing assay with co-amplification of 25 DNA-fragments and the detection of 35 human Y chromosome SNPs. The sizes of the PCR products ranged from 79 to 186 base pairs. PCR primers were designed to have a theoretical Tm of 60 +/- 5...... approximately 100 pg DNA. The minisequencing reactions were performed simultaneously for all 35 SNPs with fluorescently labelled dideoxynucleotides. The size of the minisequencing primers ranged from 19 to 106 nucleotides. The minisequencing reactions were analysed by capillary electrophoresis and multicolour...... fluorescence detection. Female DNA did not influence the results of Y chromosome SNP typing when added in concentrations more than 300 times the concentrations of male DNA. The frequencies of the 35 SNPs were determined in 194 male Danes. The gene diversity of the SNPs ranged from 0.01 to 0.5....

  16. Utility of X-chromosome SNPs in relationship testing

    DEFF Research Database (Denmark)

    Tomas, Carmen; Sanchez, Juan Jose; Castro, J.A.;

    2008-01-01

    (SNPs) in relationship testing have been published. We selected 25 highly polymorphic biallelic SNPs distributed through the human X-chromosome. One 25-plex PCR reaction and one 25-plex single base extension (SNaPshot) reaction were developed. The maximum size of the PCR products was 120ábp and the size...... of the SBE primers varied between 18 and 85 nucleotides. We analyzed the allele and haplotype frequencies in 1078 unrelated males. All the SNPs were polymorphic and the lowest minor allele frequency was 0.103. All the haplotypes were unique. The forensic parameters were calculated in the Danish and...... 25 X-chromosome SNP-multiplex may help to solve a complex immigration case...

  17. Typing of Y chromosome SNPs with multiplex PCR methods

    DEFF Research Database (Denmark)

    Sanchez Sanchez, Juan Jose; Børsting, Claus; Morling, Niels

    2005-01-01

    We describe a method for the simultaneous typing of Y-chromosome single nucleotide polymorphism (SNP) markers by means of multiplex polymerase chain reaction (PCR) strategies that allow the detection of 35 Y chromosome SNPs on 25 amplicons from 100 to 200 pg of chromosomal deoxyribonucleic acid...... factors for the creation of larger SNP typing PCR multiplexes include careful selection of primers for the primary amplification and the SBE reaction, use of DNA primers with homogenous composition, and balancing the primer concentrations for both the amplification and the SBE reactions....

  18. Study of 25 X-chromosome SNPs in the Portuguese

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    Pereira, Vania; Tomas Mas, Carmen; Amorim, António;

    2011-01-01

    The importance of X-chromosome markers in individual identifications, population genetics, forensics and kinship testing is getting wide recognition. In this work, we studied the distributions of 25 X-chromosome single nucleotide polymorphisms (X-SNPs) in population samples from Northern, Central...... and Southern Portugal (n=305). The data were also compared with previous data from the Mediterranean area confirming a general genetic homogeneity among populations in the region. The X-SNP distribution in the three Portuguese regional samples did not show any significant substructure and the X-SNP...

  19. Different molecular mechanisms causing 9p21 deletions in acute lymphoblastic leukemia of childhood.

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    Novara, Francesca; Beri, Silvana; Bernardo, Maria Ester; Bellazzi, Riccardo; Malovini, Alberto; Ciccone, Roberto; Cometa, Angela Maria; Locatelli, Franco; Giorda, Roberto; Zuffardi, Orsetta

    2009-10-01

    Deletion of chromosome 9p21 is a crucial event for the development of several cancers including acute lymphoblastic leukemia (ALL). Double strand breaks (DSBs) triggering 9p21 deletions in ALL have been reported to occur at a few defined sites by illegitimate action of the V(D)J recombination activating protein complex. We have cloned 23 breakpoint junctions for a total of 46 breakpoints in 17 childhood ALL (9 B- and 8 T-lineages) showing different size deletions at one or both homologous chromosomes 9 to investigate which particular sequences make the region susceptible to interstitial deletion. We found that half of 9p21 deletion breakpoints were mediated by ectopic V(D)J recombination mechanisms whereas the remaining half were associated to repeated sequences, including some with potential for non-B DNA structure formation. Other mechanisms, such as microhomology-mediated repair, that are common in other cancers, play only a very minor role in ALL. Nucleotide insertions at breakpoint junctions and microinversions flanking the breakpoints have been detected at 20/23 and 2/23 breakpoint junctions, respectively, both in the presence of recombination signal sequence (RSS)-like sequences and of other unspecific sequences. The majority of breakpoints were unique except for two cases, both T-ALL, showing identical deletions. Four of the 46 breakpoints coincide with those reported in other cases, thus confirming the presence of recurrent deletion hotspots. Among the six cases with heterozygous 9p deletions, we found that the remaining CDKN2A and CDKN2B alleles were hypermethylated at CpG islands. PMID:19484265

  20. Clustering of SNPs along a chromosome can the neutral model be rejected?

    CERN Document Server

    Eriksson, A; Mehlig, B

    2002-01-01

    Single nucleotide polymorphisms (SNPs) often appear in clusters along the length of a chromosome. This is due to variation in local coalescent times caused by,for example, selection or recombination. Here we investigate whether recombination alone (within a neutral model) can cause statistically significant SNP clustering. We measure the extent of SNP clustering as the ratio between the variance of SNPs found in bins of length $l$, and the mean number of SNPs in such bins, $\\sigma^2_l/\\mu_l$. For a uniform SNP distribution $\\sigma^2_l/\\mu_l=1$, for clustered SNPs $\\sigma^2_l/\\mu_l > 1$. Apart from the bin length, three length scales are important when accounting for SNP clustering: The mean distance between neighboring SNPs, $\\Delta$, the mean length of chromosome segments with constant time to the most recent common ancestor, $\\el$, and the total length of the chromosome, $L$. We show that SNP clustering is observed if $\\Delta < \\el \\ll L$. Moreover, if $l\\ll \\el \\ll L$, clustering becomes independent of ...

  1. Comments on: Association Study between Coronary Artery Disease and rs1333049 and rs10757274 Polymorphisms at 9p21 Locus in South-West Iran

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    Michael H. Preuß

    2016-02-01

    Full Text Available Foroughmand et al. (1 have recently reported association between coronary artery disease (CAD and two well-known single nucleotide polymorphisms (SNPs on chromosome 9p21.3 in subjects from South-West Iran. We doubt the validity of their findings. Genotyping was done using ARMS-PCR for rs1333049 and rs10757274 in their study. When we first looked at the genotype frequencies, we observed a substantial excess of heterozygote subjects for both SNPs. Specifically, the relative excess of heterozygosity (REH (2, a measure for the strength of deviation from Hardy-Weinberg equilibrium (HWE, was approximately 137% for rs1333049 in controls (REH=2.3688, Table 1. In contrast, we did not observe any deviation from HWE in our own studies (3, 4. We additionally conducted a short literature search to identify other studies from Asia, which reported genotype frequencies in controls for rs1333049. These studies are summarized in table 1. None of these studies shows a deviation from HWE in their control groups (all P>0.05. In summary, only the recent study by Foroughmand and colleagues (1 shows a marked deviation from HWE in controls with this deviation observed for both reported SNPs. Possible reasons for deviations from HWE have been summarized, e.g., in Ziegler et al. (2. The most likely cause for such a strong deviation from HWE is genotyping errors, especially because genotyping by ARMS-PCR plus gel electrophoresis is prone to such errors. However, REH could also be caused by population specifics, which has been discussed by Namipashaki et al. (5. In any case, we (2 and others (5 recommend the investigation of HWE in population-based genetic association studies to improve quality and reliability of the research results.

  2. Potential Signals of Natural Selection in the Top Risk Loci for Coronary Artery Disease: 9p21 and 10q11.

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    Daniela Zanetti

    Full Text Available Coronary artery disease (CAD is a complex disease and the leading cause of death in the world. Populations of different ancestry do not always share the same risk markers. Natural selective processes may be the cause of some of the population differences detected for specific risk mutations.In this study, 384 single nucleotide polymorphisms (SNPs located in four genomic regions associated with CAD (1p13, 1q41, 9p21 and 10q11 are analysed in a set of 19 populations from Europe, Middle East and North Africa and also in Asian and African samples from the 1000 Genomes Project. The aim of this survey is to explore for the first time whether the genetic variability in these genomic regions is better explained by demography or by natural selection.The results indicate significant differences in the structure of genetic variation and in the LD patterns among populations that probably explain the population disparities found in markers of susceptibility to CAD.The results are consistent with potential signature of positive selection in the 9p21 region and of balancing selection in the 9p21 and 10q11. Specifically, in Europe three CAD risk markers in the 9p21 region (rs9632884, rs1537371 and rs1333042 show consistent signals of positive selection. The results of this study are consistent with a potential selective role of CAD in the configuration of genetic diversity in current human populations.

  3. Targeted deletion of the 9p21 noncoding coronary artery disease risk interval in mice

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    Visel, Axel; Zhu, Yiwen; May, Dalit; Afzal, Veena; Gong, Elaine; Attanasio, Catia; Blow, Matthew J.; Cohen, Jonathan C.; Rubin, Edward M.; Pennacchio, Len A.

    2010-01-01

    Sequence polymorphisms in a 58kb interval on chromosome 9p21 confer a markedly increased risk for coronary artery disease (CAD), the leading cause of death worldwide 1,2. The variants have a substantial impact on the epidemiology of CAD and other life?threatening vascular conditions since nearly a quarter of Caucasians are homozygous for risk alleles. However, the risk interval is devoid of protein?coding genes and the mechanism linking the region to CAD risk has remained enigmatic. Here we show that deletion of the orthologous 70kb noncoding interval on mouse chromosome 4 affects cardiac expression of neighboring genes, as well as proliferation properties of vascular cells. Chr4delta70kb/delta70kb mice are viable, but show increased mortality both during development and as adults. Cardiac expression of two genes near the noncoding interval, Cdkn2a and Cdkn2b, is severely reduced in chr4delta70kb/delta70kb mice, indicating that distant-acting gene regulatory functions are located in the noncoding CAD risk interval. Allelespecific expression of Cdkn2b transcripts in heterozygous mice revealed that the deletion affects expression through a cis-acting mechanism. Primary cultures of chr4delta70kb/delta70kb aortic smooth muscle cells exhibited excessive proliferation and diminished senescence, a cellular phenotype consistent with accelerated CAD pathogenesis. Taken together, our results provide direct evidence that the CAD risk interval plays a pivotal role in regulation of cardiac Cdkn2a/b expression and suggest that this region affects CAD progression by altering the dynamics of vascular cell proliferation.

  4. Risk loci for coronary artery calcification replicated at 9p21 and 6q24 in the Heinz Nixdorf Recall Study

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    Pechlivanis Sonali

    2013-02-01

    Full Text Available Abstract Background Atherosclerosis is the primary cause of coronary heart disease (CHD, preceding the onset of cardiovascular disease by decades in most cases. Here we examine the association between single nucleotide polymorphisms (SNPs integrated on Metabochip and coronary artery calcification (CAC, a valid risk factor for CHD, in an unselected, population-based German cohort. Methods The Metabochip is a custom iSELECT array containing >195,000 SNPs that was designed to support large-scale follow-up of putative associations for metabolic and cardiovascular-associated traits. We used generalized linear regression models to explore the impact of Metabochip SNPs on quantitative CAC in 4,329 participants. Results The 9p21 variant, rs1537373, was most strongly associated (Beta = 0.30; 95% confidence interval (CI = 0.21-0.39; p = 4.05x10-11 with quantitative CAC. The second strongest association with CAC was with rs9349379 in the phosphatase and actin regulator 1 gene, PHACTR1, (Beta = 0.30; 95% CI = 0.22-0.40; p = 4.67x10-11. Both SNPs remained nominally significant in dichotomized analyses for the presence of any CAC (odds ratiors1537373 (OR = 1.19; 95% CI = 1.07-1.31; p = 0.001 and ORrs9349379 = 1.26; 95% CI = 1.14-1.40; p = 1.5x10-5. Fine mapping of the 9p21 and PHACTR1 gene region revealed several other SNPs that were strongly associated with CAC. Conclusion We demonstrate that SNPs near 9p21 and in PHACTR1 that have previously been shown to be associated with CHD are strongly associated with CAC in the Heinz Nixdorf Recall Study cohort. Our findings suggest that the 9p21 and 6q24 loci might be involved in cardiac outcome via promoting development of atherosclerosis in the coronary arteries.

  5. Variants in 9p21 Predicts Severity of Coronary Artery Disease in a Chinese Han Population.

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    Jing, Jinjin; Su, Li; Zeng, Ying; Tang, Xiaojun; Wei, Jie; Wang, Long; Zhou, Li

    2016-09-01

    Recent genome-wide association studies identified the common genetic variants in 9p21 were associated with the coronary artery disease (CAD). However, whether this locus could predict the severity of CAD in Chinese Han population is unclear. 499 CAD patients who underwent coronary angiography (CAG) have been enrolled for this study. The single-nucleotide polymorphisms rs2383207 and rs2383206 in 9p21 were genotyped in 499 CAG cases and 1519 controls in Chinese Han population. The gene dosage of 9p21 was stratified by the degree of vascular lesions and tested for association with the severity of CAD. Rs2383207 and rs2383206 demonstrated significant associations with 2-vessel and 3-vessel disease (P = 2.0×10(-3) and 1.9×10(-4) , respectively). GG genotypes of rs2383206 occurred higher proportion of left main trunk (LM) disease (P = 6.0×10(-3) ). GG genotypes of rs2383207 occurred higher proportion of left anterior descending artery disease (LAD) and right CAD (RCA) (P = 2.7×10(-6) and 1.6×10(-4) , respectively). The risk allele G of rs2383207 was associated with severity of CAD estimated by the Gensini score (P = 3.6×10(-5) ). Rs2383207 may strongly influence the development of CAD in Chinese Han population. The gene dosage in 9p21 could predict the severity of CAD. PMID:27461153

  6. 9p21 locus rs10757278 is associated with advanced carotid atherosclerosis in a gender-specific manner.

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    Zivotić, Ivan; Djurić, Tamara; Stanković, Aleksandra; Djordjević, Ana; Končar, Igor; Davidović, Lazar; Alavantić, Dragan; Zivković, Maja

    2016-06-01

    Single nucleotide polymorphisms from the chromosome locus 9p21 are reported to carry a risk for various cardiovascular diseases. One of the lead single nucleotide polymorphisms, rs10757278, was mostly investigated in association with coronary artery disease but rarely with carotid atherosclerosis. In this study, we aimed to analyze the association of rs10757278 A/G polymorphism with carotid plaque presence in advanced carotid atherosclerosis. The study included 803 participants, 486 patients with high-grade stenosis (>70%) who were undergoing carotid endarterectomy and 317 controls from Serbian population. Genotypes were determined using the real-time polymerase chain reaction. According to the recessive model of inheritance, GG genotype was significantly and independently associated with carotid plaque in females only (odds ratio 2.42, CI = 1.20-4.90, P = 0.013). Odds ratio was adjusted for age, body mass index, hypertension, TC, LDLC, HDLC and TG, and P value was corrected for multiple comparisons. Our preliminary findings suggest a gender-specific association of rs10757278 polymorphism with carotid plaque. Further studies on larger sample and in genetically and environmentally similar populations are needed. PMID:26941057

  7. Identification and characterization of more than 4 million intervarietal SNPs across the group 7 chromosomes of bread wheat

    OpenAIRE

    Lai, Kaitao; Lorenc, Michał T.; Lee, Hong Ching; Berkman, Paul J.; Bayer, Philipp Emanuel; Visendi, Paul; Ruperao, Pradeep; Fitzgerald, Timothy L.; Zander, Manuel; Chan, Chon-Kit Kenneth; Manoli, Sahana; Stiller, Jiri; Batley, Jacqueline; Edwards, David

    2015-01-01

    Despite being a major international crop, our understanding of the wheat genome is relatively poor due to its large size and complexity. To gain a greater understanding of wheat genome diversity, we have identified single nucleotide polymorphisms between 16 Australian bread wheat varieties. Whole-genome shotgun Illumina paired read sequence data were mapped to the draft assemblies of chromosomes 7A, 7B and 7D to identify more than 4 million intervarietal SNPs. SNP density varied between the t...

  8. CDKN2B expression and subcutaneous adipose tissue expandability: Possible influence of the 9p21 atherosclerosis locus

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Per-Arne; Wahlstrand, Björn; Olsson, Maja [Institute of Medicine, The Sahlgrenska Academy at University of Gothenburg (Sweden); Froguel, Philippe; Falchi, Mario [Department of Genomics of Common Disease, School of Public Health, Imperial College London (United Kingdom); Bergman, Richard N. [Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA (United States); McTernan, Philip G. [Division of Metabolic and Vascular Health, Warwick Medical School, University of Warwick, Coventry (United Kingdom); Hedner, Thomas; Carlsson, Lena M.S. [Institute of Medicine, The Sahlgrenska Academy at University of Gothenburg (Sweden); Jacobson, Peter, E-mail: peter.jacobson@medfak.gu.se [Institute of Medicine, The Sahlgrenska Academy at University of Gothenburg (Sweden)

    2014-04-18

    Highlights: • The tumor suppressor gene CDKN2B is highly expressed in human adipose tissue. • Risk alleles at the 9p21 locus modify CDKN2B expression in a BMI-dependent fashion. • There is an inverse relationship between expression of CDKN2B and adipogenic genes. • CDKN2B expression influences to postprandial triacylglycerol clearance. • CDKN2B expression in adipose tissue is linked to markers of hepatic steatosis. - Abstract: Risk alleles within a gene desert at the 9p21 locus constitute the most prevalent genetic determinant of cardiovascular disease. Previous research has demonstrated that 9p21 risk variants influence gene expression in vascular tissues, yet the biological mechanisms by which this would mediate atherosclerosis merits further investigation. To investigate possible influences of this locus on other tissues, we explored expression patterns of 9p21-regulated genes in a panel of multiple human tissues and found that the tumor suppressor CDKN2B was highly expressed in subcutaneous adipose tissue (SAT). CDKN2B expression was regulated by obesity status, and this effect was stronger in carriers of 9p21 risk alleles. Covariation between expression of CDKN2B and genes implemented in adipogenesis was consistent with an inhibitory effect of CDKN2B on SAT proliferation. Moreover, studies of postprandial triacylglycerol clearance indicated that CDKN2B is involved in down-regulation of SAT fatty acid trafficking. CDKN2B expression in SAT correlated with indicators of ectopic fat accumulation, including markers of hepatic steatosis. Among genes regulated by 9p21 risk variants, CDKN2B appears to play a significant role in the regulation of SAT expandability, which is a strong determinant of lipotoxicity and therefore might contribute to the development of atherosclerosis.

  9. CDKN2B expression and subcutaneous adipose tissue expandability: Possible influence of the 9p21 atherosclerosis locus

    International Nuclear Information System (INIS)

    Highlights: • The tumor suppressor gene CDKN2B is highly expressed in human adipose tissue. • Risk alleles at the 9p21 locus modify CDKN2B expression in a BMI-dependent fashion. • There is an inverse relationship between expression of CDKN2B and adipogenic genes. • CDKN2B expression influences to postprandial triacylglycerol clearance. • CDKN2B expression in adipose tissue is linked to markers of hepatic steatosis. - Abstract: Risk alleles within a gene desert at the 9p21 locus constitute the most prevalent genetic determinant of cardiovascular disease. Previous research has demonstrated that 9p21 risk variants influence gene expression in vascular tissues, yet the biological mechanisms by which this would mediate atherosclerosis merits further investigation. To investigate possible influences of this locus on other tissues, we explored expression patterns of 9p21-regulated genes in a panel of multiple human tissues and found that the tumor suppressor CDKN2B was highly expressed in subcutaneous adipose tissue (SAT). CDKN2B expression was regulated by obesity status, and this effect was stronger in carriers of 9p21 risk alleles. Covariation between expression of CDKN2B and genes implemented in adipogenesis was consistent with an inhibitory effect of CDKN2B on SAT proliferation. Moreover, studies of postprandial triacylglycerol clearance indicated that CDKN2B is involved in down-regulation of SAT fatty acid trafficking. CDKN2B expression in SAT correlated with indicators of ectopic fat accumulation, including markers of hepatic steatosis. Among genes regulated by 9p21 risk variants, CDKN2B appears to play a significant role in the regulation of SAT expandability, which is a strong determinant of lipotoxicity and therefore might contribute to the development of atherosclerosis

  10. The same sequence variant on 9p21 associates with myocardial infarction, abdominal aortic aneurysm and intracranial aneurysm

    DEFF Research Database (Denmark)

    Helgadottir, Anna; Thorleifsson, Gudmar; Magnusson, Kristinn P;

    2008-01-01

    Recently, two common sequence variants on 9p21, tagged by rs10757278-G and rs10811661-T, were reported to be associated with coronary artery disease (CAD) and type 2 diabetes (T2D), respectively. We proceeded to further investigate the contributions of these variants to arterial diseases and T2D....

  11. Identification and characterization of more than 4 million intervarietal SNPs across the group 7 chromosomes of bread wheat.

    Science.gov (United States)

    Lai, Kaitao; Lorenc, Michał T; Lee, Hong Ching; Berkman, Paul J; Bayer, Philipp Emanuel; Visendi, Paul; Ruperao, Pradeep; Fitzgerald, Timothy L; Zander, Manuel; Chan, Chon-Kit Kenneth; Manoli, Sahana; Stiller, Jiri; Batley, Jacqueline; Edwards, David

    2015-01-01

    Despite being a major international crop, our understanding of the wheat genome is relatively poor due to its large size and complexity. To gain a greater understanding of wheat genome diversity, we have identified single nucleotide polymorphisms between 16 Australian bread wheat varieties. Whole-genome shotgun Illumina paired read sequence data were mapped to the draft assemblies of chromosomes 7A, 7B and 7D to identify more than 4 million intervarietal SNPs. SNP density varied between the three genomes, with much greater density observed on the A and B genomes than the D genome. This variation may be a result of substantial gene flow from the tetraploid Triticum turgidum, which possesses A and B genomes, during early co-cultivation of tetraploid and hexaploid wheat. In addition, we examined SNP density variation along the chromosome syntenic builds and identified genes in low-density regions which may have been selected during domestication and breeding. This study highlights the impact of evolution and breeding on the bread wheat genome and provides a substantial resource for trait association and crop improvement. All SNP data are publically available on a generic genome browser GBrowse at www.wheatgenome.info. PMID:25147022

  12. Improved resolution haplogroup G phylogeny in the Y chromosome, revealed by a set of newly characterized SNPs.

    Directory of Open Access Journals (Sweden)

    Lynn M Sims

    Full Text Available BACKGROUND: Y-SNP haplogroup G (hgG, defined by Y-SNP marker M201, is relatively uncommon in the United States general population, with only 8 additional sub-markers characterized. Many of the previously described eight sub-markers are either very rare (2-4% or do not distinguish between major populations within this hg. In fact, prior to the current study, only 2% of our reference Caucasian population belonged to hgG and all of these individuals were in sub-haplogroup G2a, defined by P15. Additional Y-SNPs are needed in order to differentiate between individuals within this haplogroup. PRINCIPAL FINDINGS: In this work we have investigated whether we could differentiate between a population of 63 hgG individuals using previously uncharacterized Y-SNPs. We have designed assays to test these individuals using all known hgG SNPs (n = 9 and an additional 16 unreported/undefined Y-SNPS. Using a combination of DNA sequence and genetic genealogy databases, we have uncovered a total of 15 new hgG SNPs that had been previously reported but not phylogenetically characterized. Ten of the new Y-SNPs are phylogenetically equivalent to M201, one is equivalent to P15 and, interestingly, four create new, separate haplogroups. Three of the latter are more common than many of the previously defined Y-SNPs. Y-STR data from these individuals show that DYS385*12 is present in (70% of G2a3b1-U13 individuals while only 4% of non-G2a3b1-U13 individuals posses the DYS385*12 allele. CONCLUSIONS: This study uncovered several previously undefined Y-SNPs by using data from several database sources. The new Y-SNPs revealed in this paper will be of importance to those with research interests in population biology and human evolution.

  13. IMPACT OF LOCUS 9P21.3 SINGLE NUCLEOTIDE POLYMORPHISMS ON CORONARY ATHEROSCLEROSIS SEVERITY AND LONG-TERM OUTCOMES AFTER PERCUTANEOUS CORONARY INTERVENTION IN PATIENT WITH MYOCARDIAL INFARCTION

    Directory of Open Access Journals (Sweden)

    P. A. Shesternya

    2015-09-01

    Full Text Available Aim. To investigate association between 9p21.3 locus single nucleotide polymorphisms (SNPs and coronary atherosclerosis severity and long-term outcomes after percutaneous coronary intervention (PCI in patients with myocardial infarction (MI.Material and methods. A total of 255 Caucasian patients (211 male, 44 female; aged up to 65 years, on the average 52.56±7.98 years with MI were recruited into the study from 01.01.2009 to 30.06.2010. All participants were included into the study after written informed consent. Genome DNA was extracted from leukocytes of venous blood by the phenol-chloroform extraction method. Two SNPs rs10757278 and rs1333049 (locus 9p21.3 were tested by real-time polymerase chain reaction (PCR according to protocol (probes TaqMan, Applied Biosystems, 7900HT. The coronary angiograms were reviewed by independent angiographers who were blinded to the results of the genotyp- ing (Philips Allura Xper FD10. The total number of lesions, Gensini score and SYNTAX score were derived. Follow-up lasted two years.Results. Locus 9р21.3 genotypes CC rs1333049 and GG rs10757278 demonstrated a direct strong association with severity of coronary atheromatous burden (left main coro- nary artery stenosis, total number of lesions, Gensini score. There are not influence of locus 9p21.3 on mortality, recurrent MI, hospitalization due to unstable angina, repeated PCI, stroke during follow-up period (6, 12, 24 months. Frequency of the genotype СС rs1333049 among patients with recurrent MI was 20% (without recurrent MI — 27.4%; р=0.54; with hospitalization due to unstable angina — 27.5% (without hospitalization — 26.4%; р=0.82; with repeated PCI — 24.0% (without repeated PCI — 27.2%; р=0.97; among died patients — 29.8% (among survived ones — 26.4%; р=0.76. Frequencies of the genotype GG rs10757278 were similar: recurrent MI (yes — 18.8%; no — 26.4%; р=0.49; hospitalization due to unstable angina (yes — 28%; no — 25

  14. The contribution of a 9p21.3 variant, a KIF6 variant, and C-reactive protein to predicting risk of myocardial infarction in a prospective study

    Directory of Open Access Journals (Sweden)

    Tracy Russell P

    2011-03-01

    Full Text Available Abstract Background Genetic risk factors might improve prediction of coronary events. Several variants at chromosome 9p21.3 have been widely reported to be associated with coronary heart disease (CHD in prospective and case-control studies. A variant of KIF6 (719Arg has also been reported to be associated with increased risk of CHD in large prospective studies, but not in case-control studies. We asked whether the addition of genetic information (the 9p21.3 or KIF6 variants or a well-established non-genetic risk factor (C-reactive protein [CRP] can improve risk prediction by the Framingham Risk Score (FRS in the Cardiovascular Health Study (CHS--a prospective observational study of risk factors for cardiovascular disease among > 5,000 participants aged 65 or older. Methods Improvement of risk prediction was assessed by change in the area under the receiver-operator characteristic curve (AUC and by net reclassification improvement (NRI. Results Among white participants the FRS was improved by addition of KIF6 719Arg carrier status among men as assessed by the AUC (from 0.581 to 0.596, P = 0.03 but not by NRI (NRI = 0.027, P = 0.32. Adding both CRP and 719Arg carrier status to the FRS improved risk prediction by the AUC (0.608, P = 0.02 and NRI (0.093, P = 0.008 in men, but not women (P ≥ 0.24. Conclusions While none of these risk markers individually or in combination improved risk prediction among women, a combination of KIF6 719Arg carrier status and CRP levels modestly improved risk prediction among white men; although this improvement is not significant after multiple-testing correction. These observations should be investigated in other prospective studies.

  15. Interphase fluorescent in situ hybridization deletion analysis of the 9p21 region and prognosis in childhood acute lymphoblastic leukaemia (ALL)

    DEFF Research Database (Denmark)

    Kuchinskaya, Ekaterina; Heyman, Mats; Nordgren, Ann;

    2011-01-01

    Interphase fluorescent in situ hybridization (FISH) was applied on diagnostic BM smears from 519 children with acute lymphoblastic leukaemia (ALL) in order to establish the frequency and prognostic importance of 9p21 deletion in children enrolled in the Nordic Society of Paediatric Haematology and...... Oncology (NOPHO) - 2000 treatment protocol. Among the patients, 452 were diagnosed with B-cell precursor (BCP)-ALL and 66 with T-ALL. A higher incidence of 9p21 deletions was found in T-ALL (38%) compared to BCP-ALL (15·7%). Homozygous deletions were found in 19·7% of T-ALL and 4·0% of BCP-ALL; hemizygous...

  16. The Effect of Chromosome 9p21 Variants on Cardiovascular Disease May Be Modified by Dietary Intake: Evidence from a Case/Control and a Prospective Study

    OpenAIRE

    Ron Do; Changchun Xie; Xiaohe Zhang; Satu Männistö; Kennet Harald; Shofiqul Islam; Bailey, Swneke D.; Sumathy Rangarajan; McQueen, Matthew J.; Rafael Diaz; Liu Lisheng; Xingyu Wang; Kaisa Silander; Leena Peltonen; Salim Yusuf

    2011-01-01

    Editors' Summary Background Cardiovascular diseases (CVDs)—diseases that affect the heart and/or the blood vessels—are a leading cause of illness and death worldwide. In the United States, for example, the leading cause of death is coronary heart disease, a CVD in which narrowing of the heart's blood vessels by fatty deposits slows the blood supply to the heart and may eventually cause a heart attack (myocardial infarction, or MI); the third leading cause of death in the US is stroke, a CVD i...

  17. An evaluation of the performance of HapMap SNP data in a Shanghai Chinese population: Analyses of allele frequency, linkage disequilibrium pattern and tagging SNPs transferability on chromosome 1q21-q25

    Directory of Open Access Journals (Sweden)

    Wang Jie

    2008-02-01

    Full Text Available Abstract Background The HapMap project aimed to catalog millions of common single nucleotide polymorphisms (SNPs in the human genome in four major populations, in order to facilitate association studies of complex diseases. To examine the transferability of Han Chinese in Beijing HapMap data to the Southern Han Chinese in Shanghai, we performed comparative analyses between genotypes from over 4,500 SNPs in a 21 Mb region on chromosome 1q21-q25 in 80 unrelated Shanghai Chinese and 45 HapMap Chinese data. Results Three thousand and forty-two SNPs were analyzed after removal of SNPs that failed quality control and those not in the HapMap panel. We compared the allele frequency distributions, linkage disequilibrium patterns, haplotype frequency distributions and tagging SNP sets transferability between the HapMap population and Shanghai Chinese population. Among the four HapMap populations, Beijing Chinese showed the best correlation with Shanghai population on allele frequencies, linkage disequilibrium and haplotype frequencies. Tagging SNP sets selected from four HapMap populations at different thresholds were evaluated in the Shanghai sample. Under the threshold of r2 equal to 0.8 or 0.5, both HapMap Chinese and Japanese data showed better coverage and tagging efficiency than Caucasian and African data. Conclusion Our study supported the applicability of HapMap Beijing Chinese SNP data to the study of complex diseases among southern Chinese population.

  18. Risk loci for coronary artery calcification replicated at 9p21 and 6q24 in the Heinz Nixdorf Recall Study

    OpenAIRE

    Pechlivanis Sonali; Mühleisen Thomas W; Möhlenkamp Stefan; Schadendorf Dirk; Erbel Raimund; Jöckel Karl-Heinz; Hoffmann Per; Nöthen Markus M; Scherag André; Moebus Susanne

    2013-01-01

    Abstract Background Atherosclerosis is the primary cause of coronary heart disease (CHD), preceding the onset of cardiovascular disease by decades in most cases. Here we examine the association between single nucleotide polymorphisms (SNPs) integrated on Metabochip and coronary artery calcification (CAC), a valid risk factor for CHD, in an unselected, population-based German cohort. Methods The Metabochip is a custom iSELECT array containing >195,000 SNPs that was designed to support large-sc...

  19. Common variants at 12p11, 12q24, 9p21, 9q31.2 and in ZNF365 are associated with breast cancer risk for BRCA1 and/or BRCA2 mutation carriers

    DEFF Research Database (Denmark)

    Antoniou, Antonis C; Kuchenbaecker, Karoline B; Soucy, Penny;

    2012-01-01

    Several common alleles have been shown to be associated with breast and/or ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. Recent genome-wide association studies of breast cancer have identified eight additional breast cancer susceptibility loci: rs1011970 (9p21, CDKN2A/B), rs10995190 ...

  20. Common variants at 12p11, 12q24, 9p21, 9q31.2 and in ZNF365 are associated with breast cancer risk for BRCA1 and/or BRCA2 mutation carriers

    NARCIS (Netherlands)

    Antoniou, A.C.; Kuchenbaecker, K.B.; Soucy, P.; Beesley, J.; Chen, X.; McGuffog, L.; Lee, A.; Barrowdale, D.; Healey, S.; Sinilnikova, O.M.; Caligo, M.A.; Loman, N.; Harbst, K.; Lindblom, A.; Arver, B.; Rosenquist, R.; Karlsson, P.; Nathanson, K.; Domchek, S.; Rebbeck, T.; Jakubowska, A.; Lubinski, J.; Jaworska, K.; Durda, K.; Zlowowcka-Perlowska, E.; Osorio, A.; Duran, M.; Andres, R.; Benitez, J.; Hamann, U.; Hogervorst, F.B.; Os, T.A. van; Verhoef, S.; Meijers-Heijboer, H.E.; Wijnen, J.; Gomez Garcia, E.B.; Ligtenberg, M.J.L.; Kriege, M.; Collee, J.M.; Ausems, M.G.; Oosterwijk, J.C.; Peock, S.; Frost, D.; Ellis, S.D.; Platte, R.; Fineberg, E.; Evans, D.G.; Lalloo, F.; Jacobs, C.; Eeles, R.; Adlard, J.; Davidson, R.; Cole, T.; Cook, J.; Paterson, J.; Douglas, F.; Brewer, C.; Hodgson, S.; Morrison, P.J.; Walker, L.; Rogers, M.T.; Donaldson, A.; Dorkins, H.; Godwin, A.K.; Bove, B.; Stoppa-Lyonnet, D.; Houdayer, C.; Buecher, B.; Pauw, A. de; Mazoyer, S.; Calender, A.; Leone, M.; Bressac-de Paillerets, B.; Caron, O.; Sobol, H.; Frenay, M.; Prieur, F.; Ferrer, S.U.; Mortemousque, I.; Buys, S.; Daly, M.; Miron, A.; Terry, M.U.; Hopper, J.L.; John, E.M.; Southey, M.; Goldgar, D.; Singer, C.F.; Fink-Retter, A.; Tea, M.K.; Kaulich, D.U.; Hansen, T.V.; Nielsen, F.C.; Barkardottir, R.B.; Gaudet, M.; Kirchhoff, T.; Joseph, V.; Dutra-Clarke, A.; Offit, K.; Piedmonte, M., et al.

    2012-01-01

    INTRODUCTION: Several common alleles have been shown to be associated with breast and/or ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. Recent genome-wide association studies of breast cancer have identified eight additional breast cancer susceptibility loci: rs1011970 (9p21, CDKN2A/B),

  1. Common variants at 12p11, 12q24, 9p21, 9q31.2 and in ZNF365 are associated with breast cancer risk for BRCA1 and/or BRCA2 mutation carriers

    NARCIS (Netherlands)

    Antoniou, Antonis C.; Kuchenbaecker, Karoline B.; Soucy, Penny; Beesley, Jonathan; Chen, Xiaoqing; McGuffog, Lesley; Lee, Andrew; Barrowdale, Daniel; Healey, Sue; Sinilnikova, Olga M.; Caligo, Maria A.; Loman, Niklas; Harbst, Katja; Lindblom, Annika; Arver, Brita; Rosenquist, Richard; Karlsson, Per; Nathanson, Kate; Domchek, Susan; Rebbeck, Tim; Jakubowska, Anna; Lubinski, Jan; Jaworska, Katarzyna; Durda, Katarzyna; Zlowowcka-Perlowska, Elzbieta; Osorio, Ana; Duran, Mercedes; Andres, Raquel; Benitez, Javier; Hamann, Ute; Hogervorst, Frans B.; van Os, Theo A.; Verhoef, Senno; Meijers-Heijboer, Hanne E. J.; Wijnen, Juul; Garcia, Encarna B. Gomez; Ligtenberg, Marjolijn J.; Kriege, Mieke; Collee, Margriet; Ausems, Margreet G. E. M.; Oosterwijk, Jan C.; Peock, Susan; Frost, Debra; Ellis, Steve D.; Platte, Radka; Fineberg, Elena; Evans, D. Gareth; Lalloo, Fiona; Jacobs, Chris; Eeles, Ros; Adlard, Julian; Davidson, Rosemarie; Cole, Trevor; Cook, Jackie; Paterson, Joan; Douglas, Fiona; Brewer, Carole; Hodgson, Shirley; Morrison, Patrick J.; Walker, Lisa; Rogers, Mark T.; Donaldson, Alan; Dorkins, Huw; Godwin, Andrew K.; Bove, Betsy; Stoppa-Lyonnet, Dominique; Houdayer, Claude; Buecher, Bruno; de Pauw, Antoine; Mazoyer, Sylvie; Calender, Alain; Leone, Melanie; Bressac-de Paillerets, Brigitte; Caron, Olivier; Sobol, Hagay; Frenay, Marc; Prieur, Fabienne; Ferrer, Sandra Fert; Mortemousque, Isabelle; Buys, Saundra; Daly, Mary; Miron, Alexander; Terry, Mary Beth; Hopper, John L.; John, Esther M.; Southey, Melissa; Goldgar, David; Singer, Christian F.; Fink-Retter, Anneliese; Tea, Muy-Kheng; Kaulich, Daphne Geschwantler; Hansen, Thomas V. O.; Nielsen, Finn C.; Barkardottir, Rosa B.; Gaudet, Mia; Kirchhoff, Tomas; Joseph, Vijai; Dutra-Clarke, Ana; Offit, Kenneth; Piedmonte, Marion; Kirk, Judy; Cohn, David; Hurteau, Jean; Byron, John; Fiorica, James; Toland, Amanda E.; Montagna, Marco; Oliani, Cristina; Imyanitov, Evgeny; Isaacs, Claudine; Tihomirova, Laima; Blanco, Ignacio; Lazaro, Conxi; Teule, Alex; Del Valle, J.; Gayther, Simon A.; Odunsi, Kunle; Gross, Jenny; Karlan, Beth Y.; Olah, Edith; Teo, Soo-Hwang; Ganz, Patricia A.; Beattie, Mary S.; Dorfling, Cecelia M.; van Rensburg, Elizabeth Jansen; Diez, Orland; Kwong, Ava; Schmutzler, Rita K.; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Heidemann, Simone; Niederacher, Dieter; Preisler-Adams, Sabine; Gadzicki, Dorothea; Varon-Mateeva, Raymonda; Deissler, Helmut; Gehrig, Andrea; Sutter, Christian; Kast, Karin; Fiebig, Britta; Schaefer, Dieter; Caldes, Trinidad; de la Hoya, Miguel; Nevanlinna, Heli; Muranen, Taru A.; Lesperance, Bernard; Spurdle, Amanda B.; Neuhausen, Susan L.; Ding, Yuan C.; Wang, Xianshu; Fredericksen, Zachary; Pankratz, Vernon S.; Lindor, Noralane M.; Peterlongo, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Bonanni, Bernardo; Bernard, Loris; Dolcetti, Riccardo; Papi, Laura; Ottini, Laura; Radice, Paolo; Greene, Mark H.; Loud, Jennifer T.; Andrulis, Irene L.; Ozcelik, Hilmi; Mulligan, Anna Marie; Glendon, Gord; Thomassen, Mads; Gerdes, Anne-Marie; Jensen, Uffe B.; Skytte, Anne-Bine; Kruse, Torben A.; Chenevix-Trench, Georgia; Couch, Fergus J.; Simard, Jacques; Easton, Douglas F.

    2012-01-01

    Introduction: Several common alleles have been shown to be associated with breast and/or ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. Recent genome-wide association studies of breast cancer have identified eight additional breast cancer susceptibility loci: rs1011970 (9p21, CDKN2A/B),

  2. A Novel Cryptic Three-Way Translocation t(2;9;18(p23.2;p21.3;q21.33 with Deletion of Tumor Suppressor Genes in 9p21.3 and 13q14 in a T-Cell Acute Lymphoblastic Leukemia

    Directory of Open Access Journals (Sweden)

    Moneeb A. K. Othman

    2014-01-01

    Full Text Available Acute leukemia often presents with pure chromosomal resolution; thus, aberrations may not be detected by banding cytogenetics. Here, a case of 26-year-old male diagnosed with T-cell acute lymphoblastic leukemia (T-ALL and a normal karyotype after standard GTG-banding was studied retrospectively in detail by molecular cytogenetic and molecular approaches. Besides fluorescence in situ hybridization (FISH, multiplex ligation-dependent probe amplification (MLPA and high resolution array-comparative genomic hybridization (aCGH were applied. Thus, cryptic chromosomal aberrations not observed before were detected: three chromosomes were involved in a cytogenetically balanced occurring translocation t(2;9;18(p23.2;p21.3;q21.33. Besides a translocation t(10;14(q24;q11 was identified, an aberration known to be common in T-ALL. Due to the three-way translocation deletion of tumor suppressor genes CDKN2A/INK4A/p16, CDKN2B/INK4B/p15, and MTAP/ARF/p14 in 9p21.3 took place. Additionally RB1 in 13q14 was deleted. This patient, considered to have a normal karyotype after low resolution banding cytogenetics, was treated according to general protocol of anticancer therapy (ALL-BFM 95.

  3. Alterations of the short arm of chromosome 9p in lymphoid malignancies

    OpenAIRE

    Heyman, Mats

    1996-01-01

    CHROMOSOME 9p ALTERATIONS IN LYMPHOID MALIGNANCIES by Mats Heyman Department of Oncology-Pathology, Radiumhemmet, Karolinska Hospital and Institute, S-171 76 Stockholm, Sweden.Malignant disease evolves through the successive accumulation of genetic lesions affecting growth-controlling genes in the cell-clone undergoing malignant transformation. 9p21 has long beensusp...

  4. SNPs in putative regulatory regions identified by human mouse comparative sequencing and transcription factor binding site data

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Poulabi; Bahlo, Melanie; Schwartz, Jody R.; Loots, Gabriela G.; Houston, Kathryn A.; Dubchak, Inna; Speed, Terence P.; Rubin, Edward M.

    2002-01-01

    Genome wide disease association analysis using SNPs is being explored as a method for dissecting complex genetic traits and a vast number of SNPs have been generated for this purpose. As there are cost and throughput limitations of genotyping large numbers of SNPs and statistical issues regarding the large number of dependent tests on the same data set, to make association analysis practical it has been proposed that SNPs should be prioritized based on likely functional importance. The most easily identifiable functional SNPs are coding SNPs (cSNPs) and accordingly cSNPs have been screened in a number of studies. SNPs in gene regulatory sequences embedded in noncoding DNA are another class of SNPs suggested for prioritization due to their predicted quantitative impact on gene expression. The main challenge in evaluating these SNPs, in contrast to cSNPs is a lack of robust algorithms and databases for recognizing regulatory sequences in noncoding DNA. Approaches that have been previously used to delineate noncoding sequences with gene regulatory activity include cross-species sequence comparisons and the search for sequences recognized by transcription factors. We combined these two methods to sift through mouse human genomic sequences to identify putative gene regulatory elements and subsequently localized SNPs within these sequences in a 1 Megabase (Mb) region of human chromosome 5q31, orthologous to mouse chromosome 11 containing the Interleukin cluster.

  5. SNPs Array Karyotyping in Non-Hodgkin Lymphoma

    Directory of Open Access Journals (Sweden)

    Maryam Etebari

    2015-11-01

    Full Text Available The traditional methods for detection of chromosomal aberrations, which included cytogenetic or gene candidate solutions, suffered from low sensitivity or the need for previous knowledge of the target regions of the genome. With the advent of single nucleotide polymorphism (SNP arrays, genome screening at global level in order to find chromosomal aberrations like copy number variants, DNA amplifications, deletions, and also loss of heterozygosity became feasible. In this review, we present an update of the knowledge, gained by SNPs arrays, of the genomic complexity of the most important subtypes of non-Hodgkin lymphomas.

  6. Novel and efficient tag SNPs selection algorithms.

    Science.gov (United States)

    Chen, Wen-Pei; Hung, Che-Lun; Tsai, Suh-Jen Jane; Lin, Yaw-Ling

    2014-01-01

    SNPs are the most abundant forms of genetic variations amongst species; the association studies between complex diseases and SNPs or haplotypes have received great attention. However, these studies are restricted by the cost of genotyping all SNPs; thus, it is necessary to find smaller subsets, or tag SNPs, representing the rest of the SNPs. In fact, the existing tag SNP selection algorithms are notoriously time-consuming. An efficient algorithm for tag SNP selection was presented, which was applied to analyze the HapMap YRI data. The experimental results show that the proposed algorithm can achieve better performance than the existing tag SNP selection algorithms; in most cases, this proposed algorithm is at least ten times faster than the existing methods. In many cases, when the redundant ratio of the block is high, the proposed algorithm can even be thousands times faster than the previously known methods. Tools and web services for haplotype block analysis integrated by hadoop MapReduce framework are also developed using the proposed algorithm as computation kernels. PMID:24212035

  7. SNPs in coat colour genes in goats

    Directory of Open Access Journals (Sweden)

    L. Nicoloso

    2010-04-01

    Full Text Available Coat colour genes are useful candidates for breeds traceability of farm animals. To identify SNPs in genes involved in pigmentation in goat, we carried out in silico studies in human, mouse and cattle.We analysed 41 genes and we found: 88 SNPs in mouse, 29 synonymous and 59 non synonymous; 279 SNPs in humans, 121 synonymous and 158 non synonymous, 78 of which validated; 147 putative SNPs in cattle, 62 synonymous and 75 non synonymous, 10 of which validated. To identify the more interesting coding regions, we collected in these species information on pigmentation traits or on pathologies associated to different mutation. In goat, molecular information were available only on 7 genes and no SNP is reported, moreover poor information exists on association between mutations and different coat colour. Starting from the information collected in mouse, human and cattle, we obtained PCR products in goat for 61 exons in 36 genes. The PCR products were sequenced and checked for homology with the target sequences. Sequences on 8 animals from 4 breeds (Alpine, Saanen, Blonde of Adamello, Orobica characterised by different coat colour phenotypes have been compared, revealing 25 SNPs (11 synonymous, 14 non synonymous in 21 genes.

  8. An evaluation of the performance of tag SNPs derived from HapMap in a Caucasian population.

    Directory of Open Access Journals (Sweden)

    Alexandre Montpetit

    2006-03-01

    Full Text Available The Haplotype Map (HapMap project recently generated genotype data for more than 1 million single-nucleotide polymorphisms (SNPs in four population samples. The main application of the data is in the selection of tag single-nucleotide polymorphisms (tSNPs to use in association studies. The usefulness of this selection process needs to be verified in populations outside those used for the HapMap project. In addition, it is not known how well the data represent the general population, as only 90-120 chromosomes were used for each population and since the genotyped SNPs were selected so as to have high frequencies. In this study, we analyzed more than 1,000 individuals from Estonia. The population of this northern European country has been influenced by many different waves of migrations from Europe and Russia. We genotyped 1,536 randomly selected SNPs from two 500-kbp ENCODE regions on Chromosome 2. We observed that the tSNPs selected from the CEPH (Centre d'Etude du Polymorphisme Humain from Utah (CEU HapMap samples (derived from US residents with northern and western European ancestry captured most of the variation in the Estonia sample. (Between 90% and 95% of the SNPs with a minor allele frequency of more than 5% have an r2 of at least 0.8 with one of the CEU tSNPs. Using the reverse approach, tags selected from the Estonia sample could almost equally well describe the CEU sample. Finally, we observed that the sample size, the allelic frequency, and the SNP density in the dataset used to select the tags each have important effects on the tagging performance. Overall, our study supports the use of HapMap data in other Caucasian populations, but the SNP density and the bias towards high-frequency SNPs have to be taken into account when designing association studies.

  9. Combining SNPs in latent variables to improve genomic prediction

    DEFF Research Database (Denmark)

    Heuven, Henri C M; Rosa, G J M; Janss, Luc

    breeding were around 0.9. For the mice dataset cross validation correlations were around 0.5. Using latent vectors to combineSNPs in genomic prediction models allows for estimation of non-linear effects such as interaction among SNPs and the use of prior biological information regarding the SNPs. Keywords...

  10. Selecting additional tag SNPs for tolerating missing data in genotyping

    Directory of Open Access Journals (Sweden)

    Chen Ting

    2005-11-01

    Full Text Available Abstract Background Recent studies have shown that the patterns of linkage disequilibrium observed in human populations have a block-like structure, and a small subset of SNPs (called tag SNPs is sufficient to distinguish each pair of haplotype patterns in the block. In reality, some tag SNPs may be missing, and we may fail to distinguish two distinct haplotypes due to the ambiguity caused by missing data. Results We show there exists a subset of SNPs (referred to as robust tag SNPs which can still distinguish all distinct haplotypes even when some SNPs are missing. The problem of finding minimum robust tag SNPs is shown to be NP-hard. To find robust tag SNPs efficiently, we propose two greedy algorithms and one linear programming relaxation algorithm. The experimental results indicate that (1 the solutions found by these algorithms are quite close to the optimal solution; (2 the genotyping cost saved by using tag SNPs can be as high as 80%; and (3 genotyping additional tag SNPs for tolerating missing data is still cost-effective. Conclusion Genotyping robust tag SNPs is more practical than just genotyping the minimum tag SNPs if we can not avoid the occurrence of missing data. Our theoretical analysis and experimental results show that the performance of our algorithms is not only efficient but the solution found is also close to the optimal solution.

  11. Estimating the proportion of variation in susceptibility to schizophrenia captured by common SNPs

    DEFF Research Database (Denmark)

    Lee, S Hong; DeCandia, Teresa R; Ripke, Stephan;

    2012-01-01

    Schizophrenia is a complex disorder caused by both genetic and environmental factors. Using 9,087 affected individuals, 12,171 controls and 915,354 imputed SNPs from the Schizophrenia Psychiatric Genome-Wide Association Study (GWAS) Consortium (PGC-SCZ), we estimate that 23% (s.e. = 1%) of...... variation in liability to schizophrenia is captured by SNPs. We show that a substantial proportion of this variation must be the result of common causal variants, that the variance explained by each chromosome is linearly related to its length (r = 0.89, P = 2.6 × 10(-8)), that the genetic basis of...... schizophrenia is the same in males and females, and that a disproportionate proportion of variation is attributable to a set of 2,725 genes expressed in the central nervous system (CNS; P = 7.6 × 10(-8)). These results are consistent with a polygenic genetic architecture and imply more individual SNP...

  12. A periodic pattern of SNPs in the human genome

    DEFF Research Database (Denmark)

    Madsen, Bo Eskerod; Villesen, Palle; Wiuf, Carsten

    2007-01-01

    By surveying a filtered, high-quality set of SNPs in the human genome, we have found that SNPs positioned 1, 2, 4, 6, or 8 bp apart are more frequent than SNPs positioned 3, 5, 7, or 9 bp apart. The observed pattern is not restricted to genomic regions that are known to cause sequencing or....... It turned out that periodic DNA is mainly small regions (average length 16.9 bp), widely distributed in the genome. Furthermore, periodic DNA has a 1.8 times higher SNP density than the rest of the genome and SNPs inside periodic DNA have a significantly higher genotyping error rate than SNPs outside...... periodic DNA. Our results suggest that not all SNPs in the human genome are created by independent single nucleotide mutations, and that care should be taken in analysis of SNPs from periodic DNA. The latter may have important consequences for SNP and association studies....

  13. Chromosomal and Genetic Analysis of a Human Lung Adenocarcinoma Cell Line OM

    Institute of Scientific and Technical Information of China (English)

    Yong-Wu Li; Lin Bai; Lyu-Xia Dai; Xu He; Xian-Ping Zhou

    2016-01-01

    Background: Lung cancer has become the leading cause of death in many regions.Carcinogenesis is caused by the stepwise accumulation of genetic and chromosomal changes.The aim of this study was to investigate the chromosome and gene alterations in the human lung adenocarcinoma cell line OM.Methods: We used Giemsa banding and multiplex fluorescence in situ hybridization focusing on the human lung adenocarcinoma cell line OM to analyze its chromosome alterations.In addition, the gains and losses in the specific chromosome regions were identified by comparative genomic hybridization (CGH) and the amplifications of cancer-related genes were also detected by polymerase chain reaction (PCR).Results: We identified a large number of chromosomal numerical alterations on all chromosomes except chromosome X and 19.Chromosome 10 is the most frequently involved in translocations with six different interchromosomal translocations.CGH revealed the gains on chromosome regions of 3q25.3-28, 5p13, 12q22-23.24, and the losses on 3p25-26, 6p25, 6q26-27, 7q34-36, 8p22-23, 9p21-24, 10q25-26.3, 12p 13.31-13.33 and 17p 13.1-13.3.And PCR showed the amplification of genes: Membrane metalloendopeptidase (MME), sucrase-isomaltase (SI), butyrylcholinesterase (BCHE), and kininogen (KNG).Conclusions: The lung adenocarcinoma cell line OM exhibited multiple complex karyotypes, and chromosome 10 was frequently involved in chromosomal translocation, which may play key roles in tumorigenesis.We speculated that the oncogenes may be located at 3q25.3-28, 5p13, 12q22-23.24, while tumor suppressor genes may exist in 3p25-26, 6p25, 6q26-27, 7q34-36, 8p22-23, 9p21-24, 10q25-26.3, 12p 13.31-13.33, and 17p 13.1-13.3.Moreover, at least four genes (MME, SI, BCHE, and KNG) may be involved in the human lung adenocarcinoma cell line OM.

  14. Chromosomal and Genetic Analysis of a Human Lung Adenocarcinoma Cell Line OM

    Directory of Open Access Journals (Sweden)

    Yong-Wu Li

    2016-01-01

    Conclusions: The lung adenocarcinoma cell line OM exhibited multiple complex karyotypes, and chromosome 10 was frequently involved in chromosomal translocation, which may play key roles in tumorigenesis. We speculated that the oncogenes may be located at 3q25.3-28, 5p13, 12q22-23.24, while tumor suppressor genes may exist in 3p25-26, 6p25, 6q26-27, 7q34-36, 8p22-23, 9p21-24, 10q25-26.3, 12p13.31-13.33, and 17p13.1-13.3. Moreover, at least four genes (MME, SI, BCHE, and KNG may be involved in the human lung adenocarcinoma cell line OM.

  15. New native South American Y chromosome lineages.

    Science.gov (United States)

    Jota, Marilza S; Lacerda, Daniela R; Sandoval, José R; Vieira, Pedro Paulo R; Ohasi, Dominique; Santos-Júnior, José E; Acosta, Oscar; Cuellar, Cinthia; Revollo, Susana; Paz-Y-Miño, Cesar; Fujita, Ricardo; Vallejo, Gustavo A; Schurr, Theodore G; Tarazona-Santos, Eduardo M; Pena, Sergio Dj; Ayub, Qasim; Tyler-Smith, Chris; Santos, Fabrício R

    2016-07-01

    Many single-nucleotide polymorphisms (SNPs) in the non-recombining region of the human Y chromosome have been described in the last decade. High-coverage sequencing has helped to characterize new SNPs, which has in turn increased the level of detail in paternal phylogenies. However, these paternal lineages still provide insufficient information on population history and demography, especially for Native Americans. The present study aimed to identify informative paternal sublineages derived from the main founder lineage of the Americas-haplogroup Q-L54-in a sample of 1841 native South Americans. For this purpose, we used a Y-chromosomal genotyping multiplex platform and conventional genotyping methods to validate 34 new SNPs that were identified in the present study by sequencing, together with many Y-SNPs previously described in the literature. We updated the haplogroup Q phylogeny and identified two new Q-M3 and three new Q-L54*(xM3) sublineages defined by five informative SNPs, designated SA04, SA05, SA02, SA03 and SA29. Within the Q-M3, sublineage Q-SA04 was mostly found in individuals from ethnic groups belonging to the Tukanoan linguistic family in the northwest Amazon, whereas sublineage Q-SA05 was found in Peruvian and Bolivian Amazon ethnic groups. Within Q-L54*, the derived sublineages Q-SA03 and Q-SA02 were exclusively found among Coyaima individuals (Cariban linguistic family) from Colombia, while Q-SA29 was found only in Maxacali individuals (Jean linguistic family) from southeast Brazil. Furthermore, we validated the usefulness of several published SNPs among indigenous South Americans. This new Y chromosome haplogroup Q phylogeny offers an informative paternal genealogy to investigate the pre-Columbian history of South America.Journal of Human Genetics advance online publication, 31 March 2016; doi:10.1038/jhg.2016.26. PMID:27030145

  16. Characterization of SNPs in strawberry cultivars in China.

    Science.gov (United States)

    Ge, A J; Han, J; Li, X D; Zhao, M Z; Liu, H; Dong, Q H; Fang, J G

    2013-01-01

    Single nucleotide polymorphisms (SNPs) occur at high frequencies in both plant and animal genomes and can provide broad genome coverage and reliable estimates of genetic relationships. The availability of expressed sequence tag (EST) data has made it feasible to discover SNPs. DNA analysis is crucial in genetic studies not only for strawberry breeding programs but also for characterization of hybrids and species. We cloned 96 EST sequences, and 116 SNPs were discovered by comparing 16 strawberry cultivars grown in the region of Nanjing, China. Sequence alignment of 6 group sequences derived from 16 sample cultivars yielded 116 SNPs, within a total genomic sequence length of 1755 bp. The SNPs were discovered with a mean frequency of one SNP per 15 bp. These SNPs were comprised of 57% transitions, 32.7% transversions, 8.6% InDels, and 1.7% others, based on which a phylogenetic tree was constructed. Among the 116 SNPs, 75% were located within the open reading frame (ORF), while 25% were located outside the ORF. All 16 cultivars scattered well in dendrogram derived from the SNP data, demonstrating that SNPs can be a powerful tool for cultivar identification and genetic diversity analysis in strawberries. PMID:23546945

  17. Assessing SNPs in coat colour genes for cattle breed traceability

    Directory of Open Access Journals (Sweden)

    Paola Crepaldi

    2010-01-01

    Full Text Available Aim of this research was to identify a panel of SNPs in coat colour genes useful for breed traceability in Rendena, an autochthonous cattle breed raised in the province of Trento, and other 4 Italian cattle breeds. First, we sequenced some regions of several coat colour genes in 10 animals belonging to 5 breeds characterised by different coat colour phenotypes (Rendena, Italian Brown, Grey Alpine, Italian Friesian, and Italian Red Pied, and we detected 21 SNPs in 13 genes. These markers and 6 additional SNPs were used to genotype 180 animals of the same 5 breeds obtaining useful genotyping data for a total of 22 SNPs in 13 genes. Five out of the 22 SNP markers in the MC1R, KIT, MLPH, and SILV genes had the highest discriminating power. The panel of 22 SNPs is useful to trace Rendena particularly from Red Italian Pied and Italian Friesian.

  18. Investigation of SNPs in the porcine desmoglein 1 gene

    DEFF Research Database (Denmark)

    Daugaard, L.; Andresen, Lars Ole; Fredholm, M.

    2007-01-01

    the location of single nucleotide polymorphisms (SNPs) in the porcine desmoglein I gene (PIG)DSGI in correlation to the cleavage site as well as if the genotype of the SNPs is correlated to susceptibility or resistance to the disease. Results: DNA from 32 affected and 32 unaffected piglets with...... exudative epidermitis were diagnosed clinically as affected or unaffected. Two regions of the desmoglein I gene were sequenced and genotypes of the SNPs were established. Seven SNPs (823T>C, 828A>G, 829A>G, 830A>T, 831A>T, 838A>C and 1139C>T) were found in the analysed sequences and the allele frequencies...... were determined for the SNPs resulting in amino acid change. Four of the seven polymorphisms wre situated in the motif known to be important for toxin cleavage. The distribution of the genotypes between affected and unaffected animals was analysed. Conclusion: The study indicated a possible correlation...

  19. Introduction of an single nucleodite polymorphism-based "Major Y-chromosome haplogroup typing kit" suitable for predicting the geographical origin of male lineages

    DEFF Research Database (Denmark)

    Brión, María; Sanchez, Juan J; Balogh, Kinga;

    2005-01-01

    . From more than 200 SNPs compiled in the phylogenetic tree published by the Y-Chromosome Consortium, and looking at the population studies previously published, a package of 29 SNPs has been selected for the identification of major population haplogroups. A "Major Y-chromosome haplogroup typing kit" has...... worldwide populations. The approach takes advantage of the specific geographic distribution of the Y-chromosome haplogroups and demonstrates the utility of binary polymorphisms to infer the origin of a male lineage....

  20. Improved heritability estimation from genome-wide SNPs.

    OpenAIRE

    Speed, D; Hemani, G.; Johnson, M. R.; Balding, D. J.

    2012-01-01

    Estimation of narrow-sense heritability, h(2), from genome-wide SNPs genotyped in unrelated individuals has recently attracted interest and offers several advantages over traditional pedigree-based methods. With the use of this approach, it has been estimated that over half the heritability of human height can be attributed to the ~300,000 SNPs on a genome-wide genotyping array. In comparison, only 5%-10% can be explained by SNPs reaching genome-wide significance. We investigated via simulati...

  1. Chromosome 15q25 (CHRNA3-CHRNB4) Variation Indirectly Impacts Lung Cancer Risk in Chinese Males

    OpenAIRE

    ZHANG, YALEI; Jiang, Mei; Li, Qin; Liang, Wenhua; He, Qihua; Chen, Weiqing; He, Jianxing

    2016-01-01

    Introduction Recently, genome-wide association studies (GWAS) in Caucasian populations have identified an association between single nucleotide polymorphisms (SNPs) in the CHRNA5-A3-B4 nicotinic acetylcholine receptor subunit gene cluster on chromosome 15q25, lung cancer risk and smoking behaviors. However, these SNPs are rare in Asians, and there is currently no consensus on whether SNPs in CHRNA5-A3-B4 have a direct or indirect carcinogenic effect through smoking behaviors on lung cancer ri...

  2. Empirical testing of a 23-AIMs panel of SNPs for ancestry evaluations in four major US populations.

    Science.gov (United States)

    Zeng, Xiangpei; Warshauer, David H; King, Jonathan L; Churchill, Jennifer D; Chakraborty, Ranajit; Budowle, Bruce

    2016-07-01

    Ancestry informative markers (AIMs) can be used to determine population affiliation of the donors of forensic samples. In order to examine ancestry evaluations of the four major populations in the USA, 23 highly informative AIMs were identified from the International HapMap project. However, the efficacy of these 23 AIMs could not be fully evaluated in silico. In this study, these 23 SNPs were multiplexed to test their actual performance in ancestry evaluations. Genotype data were obtained from 189 individuals collected from four American populations. One SNP (rs12149261) on chromosome 16 was removed from this panel because it was duplicated on chromosome 1. The resultant 22-AIMs panel was able to empirically resolve the four major populations as in the in silico study. Eight individuals were assigned to a different group than indicated on their samples. The assignments of the 22 AIMs for these samples were consistent with AIMs results from the ForenSeq(TM) panel. No departures from Hardy-Weinberg equilibrium (HWE) and linkage disequilibrium (LD) were detected for all 22 SNPs in four US populations (after removing the eight problematic samples). The principal component analysis (PCA) results indicated that 181 individuals from these populations were assigned to the expected groups. These 22 SNPs can contribute to the candidate AIMs pool for potential forensic identification purposes in major US populations. PMID:26914801

  3. Regulatory SNPs in complex diseases: their identification and functional validation.

    Science.gov (United States)

    Prokunina, Ludmila; Alarcón-Riquelme, Marta E

    2004-04-01

    Finding the genetic causes for complex diseases is a challenge. Expression studies have shown that the level of expression of many genes is altered in disease compared with normal conditions, but what lies behind these changes? Linkage studies provide hints as to where in the genome the genetic triggers--the mutations--might be located. Fine-mapping and association studies can give yet more information about which genes, and which changes in the genes, are involved in the disease. Recent examples show that single-nucleotide polymorphisms (SNPs), which are variations at the single-nucleotide level within an individual's DNA, in the regulatory regions of some genes constitute susceptibility factors in many complex diseases. This article discusses the nature of regulatory SNPs (rSNPs) and techniques for their functional validation, and looks towards what rSNPs can tell us about complex diseases. PMID:15122975

  4. Analysis of mitochondrial transcription factor A SNPs in alcoholic cirrhosis

    OpenAIRE

    Tang, Chun; LIU, HONGMING; TANG, YONGLIANG; Guo, Yong; LIANG, XIANCHUN; GUO, LIPING; Pi, Ruxian; Yang, Juntao

    2013-01-01

    Genetic susceptibility to alcoholic cirrhosis (AC) exists. We previously demonstrated hepatic mitochondrial DNA (mtDNA) damage in patients with AC compared with chronic alcoholics without cirrhosis. Mitochondrial transcription factor A (mtTFA) is central to mtDNA expression regulation and repair; however, it is unclear whether there are specific mtTFA single nucleotide polymorphisms (SNPs) in patients with AC and whether they affect mtDNA repair. In the present study, we screened mtTFA SNPs i...

  5. Retrieving Y chromosomal haplogroup trees using GWAS data

    OpenAIRE

    Peng, Min-Sheng; He, Jun-Dong; Fan, Long; Liu, Jie; Adeola, Adeniyi C; Wu, Shi-Fang; Murphy, Robert W; Yao, Yong-Gang; Zhang, Ya-ping

    2013-01-01

    Phylogenetically informative Y chromosomal single-nucleotide polymorphisms (Y-SNPs) integrated in DNA chips have not been sufficiently explored in most genome-wide association studies (GWAS). Herein, we introduce a pipeline to retrieve Y-SNP data. We introduce the software YTool (http://mitotool.org/ytool/) to handle conversion, filtering, and annotation of the data. Genome-wide SNP data from populations in Myanmar are used to construct a haplogroup tree for 117 Y chromosomes based on 369 hig...

  6. Chromosomal aberration

    International Nuclear Information System (INIS)

    Chromosomal aberrations are classified into two types, chromosome-type and chromatid-type. Chromosom-type aberrations include terminal deletion, dicentric, ring and interstitial deletion, and chromatid-type aberrations include achromatic lesion, chromatid deletion, isochromatid deletion and chromatid exchange. Clastogens which induce chromosomal aberration are divided into ''S-dependent'' agents and ''S-independent''. It might mean whether they can induce double strand breaks independent of the S phase or not. Double strand breaks may be the ultimate lesions to induce chromosomal aberrations. Caffeine added even in the G2 phase appeared to modify the frequency of chromatid aberrations induced by X-rays and mitomycin C. Those might suggest that the G2 phase involves in the chromatid aberration formation. The double strand breaks might be repaired by ''G2 repair system'', the error of which might yield breakage types of chromatid aberrations and the by-pass of which might yield chromatid exchanges. Chromosome-type aberrations might be formed in the G1 phase. (author)

  7. Diagnosis of a constitutional five-chromosome rearrangement by fluorescent in situ hybridization (FISH)

    Energy Technology Data Exchange (ETDEWEB)

    Tsien, F.; Shapira, E. [Tulane Univ. School of Medicine, New Orleans, LA (United States); Carvalho, T. [Hospital Sarah Kubitschek, Brasilia (Brazil)] [and others

    1994-09-01

    Complex chromosomal rearrangements are structural rearrangements involving at least three chromosomes and three or more chromosome breakpoints. Such karyotypes are often acquired during cancer multi-step development and in chromosome instability syndromes. However, extremely rare constitutional forms have been reported, most of which are incompatible with life. We present a 2-year-old female with de novo complex rearrangement consisting of five chromosomes and nine breakpoints. Clinical evaluation at two years of age revealed a weight of 5 kg, length of 66 cm, and had circumference of 38 cm, all below the 5th percentile, microcephaly, trigonocephaly, epicanthal folds, inguinal hernia, left clubfoot, hypertonicity, and developmental delay. The neurological examination revealed chorea-acanthocytosis and psychomotor delay. Cultured lymphocytes and fibroblasts revealed a karyotype consisting of five derivative chromosomes. The metaphases were further analyzed by FISH using chromosome-specific libraries and telomeric probes in order to delineate the composition of the rearranged chromosomes; FISH results demonstrated a karyotype of: 46,XX,1pter{r_arrow}1q25::1q42.1{r_arrow}1qter, 2pter{r_arrow}q32.3::1q32.3{r_arrow}2q41::2q37.3{r_arrow}2qter, 7qter{r_arrow}7q21.2::6q22.3{r_arrow}6qter::1q31{r_arrow}1q32.3::6p23{r_arrow}6q22.3, 7pter{r_arrow}7q21.1::6p23{r_arrow}6pter, 2q33{r_arrow}2q37, 1::9p21{r_arrow}9qter. This analysis demonstrates the usefulness of FISH in characterizing complex chromosome rearrangements otherwise difficult to correctly interpret using classical cytogenetics alone.

  8. The genomic distribution of population substructure in four populations using 8,525 autosomal SNPs

    Directory of Open Access Journals (Sweden)

    Shriver Mark D

    2004-05-01

    Full Text Available Abstract Understanding the nature of evolutionary relationships among persons and populations is important for the efficient application of genome science to biomedical research. We have analysed 8,525 autosomal single nucleotide polymorphisms (SNPs in 84 individuals from four populations: African-American, European-American, Chinese and Japanese. Individual relationships were reconstructed using the allele sharing distance and the neighbour-joining tree making method. Trees show clear clustering according to population, with the root branching from the African-American clade. The African-American cluster is much less star-like than European-American and East Asian clusters, primarily because of admixture. Furthermore, on the East Asian branch, all ten Chinese individuals cluster together and all ten Japanese individuals cluster together. Using positional information, we demonstrate strong correlations between inter-marker distance and both locus-specific FST (the proportion of total variation due to differentiation levels and branch lengths. Chromosomal maps of the distribution of locus-specific branch lengths were constructed by combining these data with other published SNP markers (total of 33,704 SNPs. These maps clearly illustrate a non-uniform distribution of human genetic substructure, an instructional and useful paradigm for education and research.

  9. Analysis and visualization of chromosomal abnormalities in SNP data with SNPscan

    OpenAIRE

    Thomas George H; Ye Ying; Ting Jason C; Ruczinski Ingo; Pevsner Jonathan

    2006-01-01

    Abstract Background A variety of diseases are caused by chromosomal abnormalities such as aneuploidies (having an abnormal number of chromosomes), microdeletions, microduplications, and uniparental disomy. High density single nucleotide polymorphism (SNP) microarrays provide information on chromosomal copy number changes, as well as genotype (heterozygosity and homozygosity). SNP array studies generate multiple types of data for each SNP site, some with more than 100,000 SNPs represented on e...

  10. Synthetic chromosomes.

    Science.gov (United States)

    Schindler, Daniel; Waldminghaus, Torsten

    2015-11-01

    What a living organism looks like and how it works and what are its components-all this is encoded on DNA, the genetic blueprint. Consequently, the way to change an organism is to change its genetic information. Since the first pieces of recombinant DNA have been used to transform cells in the 1970s, this approach has been enormously extended. Bigger and bigger parts of the genetic information have been exchanged or added over the years. Now we are at a point where the construction of entire chromosomes becomes a reachable goal and first examples appear. This development leads to fundamental new questions, for example, about what is possible and desirable to build or what construction rules one needs to follow when building synthetic chromosomes. Here we review the recent progress in the field, discuss current challenges and speculate on the appearance of future synthetic chromosomes. PMID:26111960

  11. Mapping and linkage disequilibrium analysis with a genome-wide collection of SNPs that detect polymorphism in cultivated tomato

    Science.gov (United States)

    Robbins, Matthew D.; Yang, Wencai; Van Deynze, Allen; van der Knaap, Esther; Joobeur, Tarek; Francis, David M.

    2011-01-01

    The history of tomato (Solanum lycopersicum L.) improvement includes genetic bottlenecks, wild species introgressions, and divergence into distinct market classes. This history makes tomato an excellent model to investigate the effects of selection on genome variation. A combination of linkage mapping in two F2 populations and physical mapping with emerging genome sequence data was used to position 434 PCR-based markers including SNPs. Three-hundred-and-forty markers were used to genotype 102 tomato lines representing wild species, landraces, vintage cultivars, and contemporary (fresh market and processing) varieties. Principal component analysis confirmed genetic divergence between market classes of cultivated tomato (P <0.0001). A genome-wide survey indicated that linkage disequilibrium (LD) decays over 6–8 cM when all cultivated tomatoes, including vintage and contemporary, were considered together. Within contemporary processing varieties, LD decayed over 6–14 cM, and decay was over 3–16 cM within fresh market varieties. Significant inter-chromosomal (gametic phase) LD was detected in both fresh market and processing varieties between chromosomes 2 and 3, and 2 and 4, but in distinct chromosomal locations for each market class. Additional LD was detected between chromosomes 3 and 4, 3 and 11, and 4 and 6 in fresh market varieties and chromosomes 3 and 12 in processing varieties. These results suggest that breeding practices for market specialization in tomato have led to a genetic divergence between fresh market and processing types. PMID:21193580

  12. SNP-RFLPing: restriction enzyme mining for SNPs in genomes

    OpenAIRE

    Cheng Yu-Huei; Chang Phei-Lang; Yang Cheng-Hong; Chang Hsueh-Wei; Chuang Li-Yeh

    2006-01-01

    Abstract Background The restriction fragment length polymorphism (RFLP) is a common laboratory method for the genotyping of single nucleotide polymorphisms (SNPs). Here, we describe a web-based software, named SNP-RFLPing, which provides the restriction enzyme for RFLP assays on a batch of SNPs and genes from the human, rat, and mouse genomes. Results Three user-friendly inputs are included: 1) NCBI dbSNP "rs" or "ss" IDs; 2) NCBI Entrez gene ID and HUGO gene name; 3) any formats of SNP-in-se...

  13. High density genome wide genotyping-by-sequencing and association identifies common and low frequency SNPs, and novel candidate genes influencing cow milk traits

    Science.gov (United States)

    Ibeagha-Awemu, Eveline M.; Peters, Sunday O.; Akwanji, Kingsley A.; Imumorin, Ikhide G.; Zhao, Xin

    2016-01-01

    High-throughput sequencing technologies have increased the ability to detect sequence variations for complex trait improvement. A high throughput genome wide genotyping-by-sequencing (GBS) method was used to generate 515,787 single nucleotide polymorphisms (SNPs), from which 76,355 SNPs with call rates >85% and minor allele frequency ≥1.5% were used in genome wide association study (GWAS) of 44 milk traits in 1,246 Canadian Holstein cows. GWAS was accomplished with a mixed linear model procedure implementing the additive and dominant models. A strong signal within the centromeric region of bovine chromosome 14 was associated with test day fat percentage. Several SNPs were associated with eicosapentaenoic acid, docosapentaenoic acid, arachidonic acid, CLA:9c11t and gamma linolenic acid. Most of the significant SNPs for 44 traits studied are novel and located in intergenic regions or introns of genes. Novel potential candidate genes for milk traits or mammary gland functions include ERCC6, TONSL, NPAS2, ACER3, ITGB4, GGT6, ACOX3, MECR, ADAM12, ACHE, LRRC14, FUK, NPRL3, EVL, SLCO3A1, PSMA4, FTO, ADCK5, PP1R16A and TEP1. Our study further demonstrates the utility of the GBS approach for identifying population-specific SNPs for use in improvement of complex dairy traits. PMID:27506634

  14. Multistudy fine mapping of chromosome 2q identifies XRCC5 as a chronic obstructive pulmonary disease susceptibility gene

    DEFF Research Database (Denmark)

    Hersh, Craig P; Pillai, Sreekumar G; Zhu, Guohua;

    2010-01-01

    RATIONALE: Several family-based studies have identified genetic linkage for lung function and airflow obstruction to chromosome 2q. OBJECTIVES: We hypothesized that merging results of high-resolution single nucleotide polymorphism (SNP) mapping in four separate populations would lead to the...... identification of chronic obstructive pulmonary disease (COPD) susceptibility genes on chromosome 2q. METHODS: Within the chromosome 2q linkage region, 2,843 SNPs were genotyped in 806 COPD cases and 779 control subjects from Norway, and 2,484 SNPs were genotyped in 309 patients with severe COPD from the...... in the Boston Early-Onset COPD Study. MEASUREMENTS AND MAIN RESULTS: Merging the results of the two case-control analyses, 14 of the 790 overlapping SNPs had a combined P < 0.01. Two of these 14 SNPs were consistently associated with COPD in the ICGN families. The association with one SNP, located in...

  15. Inherited variants in the inner centromere protein (INCENP) gene of the chromosomal passenger complex contribute to the susceptibility of ER-negative breast cancer

    DEFF Research Database (Denmark)

    Kabisch, Maria; Lorenzo Bermejo, Justo; Dünnebier, Thomas;

    2015-01-01

    The chromosomal passenger complex (CPC) plays a pivotal role in the regulation of cell division. Therefore, inherited CPC variability could influence tumor development. The present candidate gene approach investigates the relationship between single nucleotide polymorphisms (SNPs) in genes encodi...

  16. Chromosome Microarray.

    Science.gov (United States)

    Anderson, Sharon

    2016-01-01

    Over the last half century, knowledge about genetics, genetic testing, and its complexity has flourished. Completion of the Human Genome Project provided a foundation upon which the accuracy of genetics, genomics, and integration of bioinformatics knowledge and testing has grown exponentially. What is lagging, however, are efforts to reach and engage nurses about this rapidly changing field. The purpose of this article is to familiarize nurses with several frequently ordered genetic tests including chromosomes and fluorescence in situ hybridization followed by a comprehensive review of chromosome microarray. It shares the complexity of microarray including how testing is performed and results analyzed. A case report demonstrates how this technology is applied in clinical practice and reveals benefits and limitations of this scientific and bioinformatics genetic technology. Clinical implications for maternal-child nurses across practice levels are discussed. PMID:27276104

  17. Combinations of SNPs related to signal transduction in bipolar disorder

    DEFF Research Database (Denmark)

    Koefoed, Pernille; Andreassen, Ole A; Bennike, Bente;

    2011-01-01

    Any given single nucleotide polymorphism (SNP) in a genome may have little or no functional impact. A biologically significant effect may possibly emerge only when a number of key SNP-related genotypes occur together in a single organism. Thus, in analysis of many SNPs in association studies of...... complex diseases, it may be useful to look at combinations of genotypes. Genes related to signal transmission, e.g., ion channel genes, may be of interest in this respect in the context of bipolar disorder. In the present study, we analysed 803 SNPs in 55 genes related to aspects of signal transmission...... and calculated all combinations of three genotypes from the 3×803 SNP genotypes for 1355 controls and 607 patients with bipolar disorder. Four clusters of patient-specific combinations were identified. Permutation tests indicated that some of these combinations might be related to bipolar disorder...

  18. Computational screening and molecular dynamics simulation of disease associated nsSNPs in CENP-E

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Ambuj [Bioinformatics Division, School of Bio Sciences and Technology, Vellore Institute of Technology University, Vellore 632014, Tamil Nadu (India); Purohit, Rituraj, E-mail: riturajpurohit@gmail.com [Bioinformatics Division, School of Bio Sciences and Technology, Vellore Institute of Technology University, Vellore 632014, Tamil Nadu (India)

    2012-10-15

    Aneuploidy and chromosomal instability (CIN) are hallmarks of most solid tumors. Mutations in centroemere proteins have been observed in promoting aneuploidy and tumorigenesis. Recent studies reported that Centromere-associated protein-E (CENP-E) is involved in inducing cancers. In this study we investigated the pathogenic effect of 132 nsSNPs reported in CENP-E using computational platform. Y63H point mutation found to be associated with cancer using SIFT, Polyphen, PhD-SNP, MutPred, CanPredict and Dr. Cancer tools. Further we investigated the binding affinity of ATP molecule to the CENP-E motor domain. Complementarity scores obtained from docking studies showed significant loss in ATP binding affinity of mutant structure. Molecular dynamics simulation was carried to examine the structural consequences of Y63H mutation. Root mean square deviation (RMSD), root mean square fluctuation (RMSF), radius of gyration (R{sub g}), solvent accessibility surface area (SASA), energy value, hydrogen bond (NH Bond), eigenvector projection, trace of covariance matrix and atom density analysis results showed notable loss in stability for mutant structure. Y63H mutation was also shown to disrupt the native conformation of ATP binding region in CENP-E motor domain. Docking studies for remaining 18 mutations at 63rd residue position as well as other two computationally predicted disease associated mutations S22L and P69S were also carried to investigate their affect on ATP binding affinity of CENP-E motor domain. Our study provided a promising computational methodology to study the tumorigenic consequences of nsSNPs that have not been characterized and clear clue to the wet lab scientist.

  19. A consensus linkage map of the grass carp (Ctenopharyngodon idella based on microsatellites and SNPs

    Directory of Open Access Journals (Sweden)

    Li Jiale

    2010-02-01

    Full Text Available Abstract Background Grass carp (Ctenopharyngodon idella belongs to the family Cyprinidae which includes more than 2000 fish species. It is one of the most important freshwater food fish species in world aquaculture. A linkage map is an essential framework for mapping traits of interest and is often the first step towards understanding genome evolution. The aim of this study is to construct a first generation genetic map of grass carp using microsatellites and SNPs to generate a new resource for mapping QTL for economically important traits and to conduct a comparative mapping analysis to shed new insights into the evolution of fish genomes. Results We constructed a first generation linkage map of grass carp with a mapping panel containing two F1 families including 192 progenies. Sixteen SNPs in genes and 263 microsatellite markers were mapped to twenty-four linkage groups (LGs. The number of LGs was corresponding to the haploid chromosome number of grass carp. The sex-specific map was 1149.4 and 888.8 cM long in females and males respectively whereas the sex-averaged map spanned 1176.1 cM. The average resolution of the map was 4.2 cM/locus. BLAST searches of sequences of mapped markers of grass carp against the whole genome sequence of zebrafish revealed substantial macrosynteny relationship and extensive colinearity of markers between grass carp and zebrafish. Conclusions The linkage map of grass carp presented here is the first linkage map of a food fish species based on co-dominant markers in the family Cyprinidae. This map provides a valuable resource for mapping phenotypic variations and serves as a reference to approach comparative genomics and understand the evolution of fish genomes and could be complementary to grass carp genome sequencing project.

  20. Computational screening and molecular dynamics simulation of disease associated nsSNPs in CENP-E

    International Nuclear Information System (INIS)

    Aneuploidy and chromosomal instability (CIN) are hallmarks of most solid tumors. Mutations in centroemere proteins have been observed in promoting aneuploidy and tumorigenesis. Recent studies reported that Centromere-associated protein-E (CENP-E) is involved in inducing cancers. In this study we investigated the pathogenic effect of 132 nsSNPs reported in CENP-E using computational platform. Y63H point mutation found to be associated with cancer using SIFT, Polyphen, PhD-SNP, MutPred, CanPredict and Dr. Cancer tools. Further we investigated the binding affinity of ATP molecule to the CENP-E motor domain. Complementarity scores obtained from docking studies showed significant loss in ATP binding affinity of mutant structure. Molecular dynamics simulation was carried to examine the structural consequences of Y63H mutation. Root mean square deviation (RMSD), root mean square fluctuation (RMSF), radius of gyration (Rg), solvent accessibility surface area (SASA), energy value, hydrogen bond (NH Bond), eigenvector projection, trace of covariance matrix and atom density analysis results showed notable loss in stability for mutant structure. Y63H mutation was also shown to disrupt the native conformation of ATP binding region in CENP-E motor domain. Docking studies for remaining 18 mutations at 63rd residue position as well as other two computationally predicted disease associated mutations S22L and P69S were also carried to investigate their affect on ATP binding affinity of CENP-E motor domain. Our study provided a promising computational methodology to study the tumorigenic consequences of nsSNPs that have not been characterized and clear clue to the wet lab scientist.

  1. SNPs and Hox gene mapping in Ciona intestinalis

    Directory of Open Access Journals (Sweden)

    Biffali Elio

    2008-01-01

    Full Text Available Abstract Background The tunicate Ciona intestinalis (Enterogona, Ascidiacea, a major model system for evolutionary and developmental genetics of chordates, harbours two cryptic species. To assess the degree of intra- and inter-specific genetic variability, we report the identification and analysis of C. intestinalis SNP (Single Nucleotide Polymorphism markers. A SNP subset was used to determine the genetic distance between Hox-5 and -10 genes. Results DNA fragments were amplified from 12 regions of C. intestinalis sp. A. In total, 128 SNPs and 32 one bp indels have been identified within 8 Kb DNA. SNPs in coding regions cause 4 synonymous and 12 non-synonymous substitutions. The highest SNP frequency was detected in the Hox5 and Hox10 intragenic regions. In C. intestinalis, these two genes have lost their archetypal topology within the cluster, such that Hox10 is located between Hox4 and Hox5. A subset of the above primers was used to perform successful amplification in C. intestinalis sp. B. In this cryptic species, 62 SNPs were identified within 3614 bp: 41 in non-coding and 21 in coding regions. The genetic distance of the Hox-5 and -10 loci, computed combining a classical backcross approach with the application of SNP markers, was found to be 8.4 cM (Haldane's function. Based on the physical distance, 1 cM corresponds to 39.5 Kb. Linkage disequilibrium between the aforementioned loci was calculated in the backcross generation. Conclusion SNPs here described allow analysis and comparisons within and between C. intestinalis cryptic species. We provide the first reliable computation of genetic distance in this important model chordate. This latter result represents an important platform for future studies on Hox genes showing deviations from the archetypal topology.

  2. Consortium analysis of 7 candidate SNPs for ovarian cancer

    DEFF Research Database (Denmark)

    Ramus, S.J.; Vierkant, R.A.; Johnatty, S.E.;

    2008-01-01

    The Ovarian Cancer Association Consortium selected 7 candidate single nucleotide polymorphisms (SNPs), for which there is evidence from previous studies of an association with variation in ovarian cancer or breast cancer risks. The SNPs selected for analysis were F31I (rs2273535) in AURKA, N372H...... suggestive although no longer statistically significant (ordinal OR 0.92, 95% CI 0.79-1.06). This SNP has also been shown to have an association with decreased risk in breast cancer. There was a suggestion of an association for AURKA, when one study that caused significant study heterogeneity was excluded...... [ordinal OR 1.10 (95% CI 1.01-1.20) p = 0.027; dominant OR 1.12 (95% CI 1.01-1.24) p = 0.03]. The other 5 SNPs in BRCA2, CDKN2A, SRD5A2, CASP8 and TGFB1 showed no association with ovarian cancer risk; given the large sample size, these results can also be considered to be informative. These null results...

  3. Comparison of SNPs and microsatellites in identifying offtypes of cacao clones from Cameroon

    Science.gov (United States)

    Single Nucleotide Polymorphism (SNP) markers are increasingly being used in crop breeding programs, slowly replacing microsatellites and other markers. SNPs provide many benefits over microsatellites, including ease of analysis and unambiguous results across various platforms. We compare SNPs to m...

  4. SNP@Promoter: a database of human SNPs (Single Nucleotide Polymorphisms) within the putative promoter regions

    OpenAIRE

    Chung Won-Hyong; Park Daeui; Kim Woo-Yeon; Kim Byoung-Chul; Shin Kwang-sik; Bhak Jong

    2008-01-01

    Abstract Background Analysis of single nucleotide polymorphism (SNP) is becoming a key research in genomics fields. Many functional analyses of SNPs have been carried out for coding regions and splicing sites that can alter proteins and mRNA splicing. However, SNPs in non-coding regulatory regions can also influence important biological regulation. Presently, there are few databases for SNPs in non-coding regulatory regions. Description We identified 488,452 human SNPs in the putative promote...

  5. SNPs Selection using Gravitational Search Algorithm and Exhaustive Search for Association Mapping

    Science.gov (United States)

    Kusuma, W. A.; Hasibuan, L. S.; Istiadi, M. A.

    2016-01-01

    Single Nucleotide Polymorphisms (SNPs) are known having association to phenotipic variations. The study of linking SNPs to interest phenotype is refer to Association Mapping (AM), which is classified as a combinatorial problem. Exhaustive Search (ES) approach is able to be implemented to select targeted SNPs exactly since it evaluate all possible combinations of SNPs, but it is not efficient in terms of computer resources and computation time. Heuristic Search (HS) approach is an alternative to improve the performance of ES in those terms, but it still suffers high false positive SNPs in each combinations. Gravitational Search Algorithm (GSA) is a new HS algorithm that yields better performance than other nature inspired HS. This paper proposed a new method which combined GSA and ES to identify the most appropriate combination of SNPs linked to interest phenotype. Testing was conducted using dataset without epistasis and dataset with epistasis. Using dataset without epistasis with 7 targeted SNPs, the proposed method identified 7 SNPs - 6 True Positive (TP) SNPs and 1 False Positive (FP) SNP- with association value of 0.83. In addition, the proposed method could identified 3 SNPs- 2 TP SNP and 1 FP SNP with association value of 0.87 by using dataset with epistases and 5 targeted SNPs. The results showed that the method is robust in reducing redundant SNPs and identifying main markers.

  6. Identification of functional SNPs in the 5-prime flanking sequences of human genes

    Directory of Open Access Journals (Sweden)

    Lenhard Boris

    2005-02-01

    Full Text Available Abstract Background Over 4 million single nucleotide polymorphisms (SNPs are currently reported to exist within the human genome. Only a small fraction of these SNPs alter gene function or expression, and therefore might be associated with a cell phenotype. These functional SNPs are consequently important in understanding human health. Information related to functional SNPs in candidate disease genes is critical for cost effective genetic association studies, which attempt to understand the genetics of complex diseases like diabetes, Alzheimer's, etc. Robust methods for the identification of functional SNPs are therefore crucial. We report one such experimental approach. Results Sequence conserved between mouse and human genomes, within 5 kilobases of the 5-prime end of 176 GPCR genes, were screened for SNPs. Sequences flanking these SNPs were scored for transcription factor binding sites. Allelic pairs resulting in a significant score difference were predicted to influence the binding of transcription factors (TFs. Ten such SNPs were selected for mobility shift assays (EMSA, resulting in 7 of them exhibiting a reproducible shift. The full-length promoter regions with 4 of the 7 SNPs were cloned in a Luciferase based plasmid reporter system. Two out of the 4 SNPs exhibited differential promoter activity in several human cell lines. Conclusions We propose a method for effective selection of functional, regulatory SNPs that are located in evolutionary conserved 5-prime flanking regions (5'-FR regions of human genes and influence the activity of the transcriptional regulatory region. Some SNPs behave differently in different cell types.

  7. Genotyping of Brucella species using clade specific SNPs

    Directory of Open Access Journals (Sweden)

    Foster Jeffrey T

    2012-06-01

    Full Text Available Abstract Background Brucellosis is a worldwide disease of mammals caused by Alphaproteobacteria in the genus Brucella. The genus is genetically monomorphic, requiring extensive genotyping to differentiate isolates. We utilized two different genotyping strategies to characterize isolates. First, we developed a microarray-based assay based on 1000 single nucleotide polymorphisms (SNPs that were identified from whole genome comparisons of two B. abortus isolates , one B. melitensis, and one B. suis. We then genotyped a diverse collection of 85 Brucella strains at these SNP loci and generated a phylogenetic tree of relationships. Second, we developed a selective primer-extension assay system using capillary electrophoresis that targeted 17 high value SNPs across 8 major branches of the phylogeny and determined their genotypes in a large collection ( n = 340 of diverse isolates. Results Our 1000 SNP microarray readily distinguished B. abortus, B. melitensis, and B. suis, differentiating B. melitensis and B. suis into two clades each. Brucella abortus was divided into four major clades. Our capillary-based SNP genotyping confirmed all major branches from the microarray assay and assigned all samples to defined lineages. Isolates from these lineages and closely related isolates, among the most commonly encountered lineages worldwide, can now be quickly and easily identified and genetically characterized. Conclusions We have identified clade-specific SNPs in Brucella that can be used for rapid assignment into major groups below the species level in the three main Brucella species. Our assays represent SNP genotyping approaches that can reliably determine the evolutionary relationships of bacterial isolates without the need for whole genome sequencing of all isolates.

  8. Molecular Beacon CNT-based Detection of SNPs

    Science.gov (United States)

    Egorova, V. P.; Krylova, H. V.; Lipnevich, I. V.; Veligura, A. A.; Shulitsky, B. G.; Y Fedotenkova, L.

    2015-11-01

    An fluorescence quenching effect due to few-walled carbon nanotubes chemically modified by carboxyl groups has been utilized to discriminate Single Nucleotide Polymorphism (SNP). It was shown that the complex obtained from these nanotube and singlestranded primer DNA is formed due to stacking interactions between the hexagons of the nanotubes and aromatic rings of nucleotide bases as well as due to establishing of hydrogen bonds between acceptor amine groups of nucleotide bases and donor carboxyl groups of the nanotubes. It has been demonstrated that these complexes may be used to make highly effective DNA biosensors detecting SNPs which operate as molecular beacons.

  9. Analysis of 49 autosomal SNPs in an Iraqi population

    DEFF Research Database (Denmark)

    Tomas Mas, Carmen; Diez, Isabel E; Moncada, Enrique;

    2013-01-01

    Forty-nine of the 52 autosomal single nucleotide polymorphisms (SNPs) in the SNPforID 52plex were typed in 101 unrelated Iraqis living in Denmark. No significant deviation from HWE was found in all but one of the 49 SNP systems and no significant pairwise linkage disequilibrium was observed for any...... SNP pair. When 18 worldwide populations were compared (including populations in Iraq, Turkey, Israel, Pakistan, India, China, Taiwan, Japan, Siberia, Algeria, Somalia, Uganda, Mozambique, Angola, Nigeria, Denmark, Portugal, Spain), a significant global F(ST) value was obtained. All but six F...

  10. Taiwan Y-chromosomal DNA variation and its relationship with Island Southeast Asia

    OpenAIRE

    Trejaut, Jean A; Poloni, Estella S.; Yen, Ju-Chen; Lai, Ying-Hui; Loo, Jun-Hun; Lee, Chien-Liang; He, Chun-Lin; Lin, Marie

    2014-01-01

    BACKGROUND: Much of the data resolution of the haploid non-recombining Y chromosome (NRY) haplogroup O in East Asia are still rudimentary and could be an explanatory factor for current debates on the settlement history of Island Southeast Asia (ISEA). Here, 81 slowly evolving markers (mostly SNPs) and 17 Y-chromosomal short tandem repeats were used to achieve higher level molecular resolution. Our aim is to investigate if the distribution of NRY DNA variation in Taiwan and ISEA is consistent ...

  11. Identification of candidate genes for dyslexia susceptibility on chromosome 18.

    Directory of Open Access Journals (Sweden)

    Thomas S Scerri

    Full Text Available Six independent studies have identified linkage to chromosome 18 for developmental dyslexia or general reading ability. Until now, no candidate genes have been identified to explain this linkage. Here, we set out to identify the gene(s conferring susceptibility by a two stage strategy of linkage and association analysis.Linkage analysis: 264 UK families and 155 US families each containing at least one child diagnosed with dyslexia were genotyped with a dense set of microsatellite markers on chromosome 18. Association analysis: Using a discovery sample of 187 UK families, nearly 3000 SNPs were genotyped across the chromosome 18 dyslexia susceptibility candidate region. Following association analysis, the top ranking SNPs were then genotyped in the remaining samples. The linkage analysis revealed a broad signal that spans approximately 40 Mb from 18p11.2 to 18q12.2. Following the association analysis and subsequent replication attempts, we observed consistent association with the same SNPs in three genes; melanocortin 5 receptor (MC5R, dymeclin (DYM and neural precursor cell expressed, developmentally down-regulated 4-like (NEDD4L.Along with already published biological evidence, MC5R, DYM and NEDD4L make attractive candidates for dyslexia susceptibility genes. However, further replication and functional studies are still required.

  12. Genetic variation of goat Y chromosome in the Sardinian population

    Directory of Open Access Journals (Sweden)

    Antonello Carta

    2010-01-01

    Full Text Available Sardinian goat population is commonly considered a crossbred of autochthonous animals with improved Mediterranean breeds, mainly the Maltese. It has been demonstrated by using autosomal microsatellites that the Sardinian goats can be divided into three subpopulations: Sardinian, crossbred with Maltese, and Maltese. The aim of this study was to evaluate sequence variation at Y chromosome in Sardinian bucks and to integrate autosomal microsatellites data. Blood from 190 bucks from 68 farms spread in the main Sardinian goat farming areas was sampled. Three ECONOGENE project primer pairs plus an additional one corresponding to a total of 7 SNPs were used. For all common SNPs, the most frequent allele corresponded to the ECONOGENE one. The additional analysed SNP showed allelic frequencies similar to the other markers. The comparison with haplotypes based on the 6 common SNPs showed that the Sardinian most frequent haplotype corresponded to the predominant one in Central Europe. Results of this study showed that the Sardinian goat population has 8 haplotypes resulting in a large diversity of paternal lineages. The next step will be linking autosomal information to Y chromosome data. In fact, up to date, it seems unfeasible to detect recent upgrading breeds by using Y chromosome variation only.

  13. Tetra-allelic SNPs: Informative forensic markers compiled from public whole-genome sequence data.

    Science.gov (United States)

    Phillips, C; Amigo, J; Carracedo, Á; Lareu, M V

    2015-11-01

    Multiple-allele single nucleotide polymorphisms (SNPs) are potentially useful for forensic DNA analysis as they can provide more discrimination power than normal binary SNPs. In addition, the presence in a profile of more than two alleles per marker provides a clearer indication of mixed DNA than assessments of imbalanced signals in the peak pairs of binary SNPs. Using the 1000 Genomes Phase III human variant data release of 2014 as the starting point, this study collated 961 tetra-allelic SNPs that pass minimum sequence quality thresholds and where four separate nucleotide substitution alleles were detected. Although most of these loci had three of the four alleles in combined frequencies of 2% or less, 160 had high heterozygosities with 50 exceeding those of 'ideal' 0.5:0.5 binary SNPs. From this set of most polymorphic tetra-allelic SNPs, we identified markers most informative for forensic purposes and explored these loci in detail. Subsets of the most polymorphic tetra-allelic SNPs will make useful additions to current panels of forensic identification SNPs and ancestry-informative SNPs. The 24 most discriminatory tetra-allelic SNPs were estimated to detect more than two alleles in at least one marker per profile in 99.9% of mixtures of African contributors. In European contributor mixtures 99.4% of profiles would show multiple allele patterns, but this drops to 92.6% of East Asian contributor mixtures due to reduced levels of polymorphism for the 24 SNPs in this population group. PMID:26209763

  14. A survey of endogenous retrovirus (ERV) sequences in the vicinity of multiple sclerosis (MS)-associated single nucleotide polymorphisms (SNPs).

    Science.gov (United States)

    Brütting, Christine; Emmer, Alexander; Kornhuber, Malte; Staege, Martin S

    2016-08-01

    Although multiple sclerosis (MS) is one of the most common central nervous system diseases in young adults, little is known about its etiology. Several human endogenous retroviruses (ERVs) are considered to play a role in MS. We are interested in which ERVs can be identified in the vicinity of MS associated genetic marker to find potential initiators of MS. We analysed the chromosomal regions surrounding 58 single nucleotide polymorphisms (SNPs) that are associated with MS identified in one of the last major genome wide association studies. We scanned these regions for putative endogenous retrovirus sequences with large open reading frames (ORFs). We observed that more retrovirus-related putative ORFs exist in the relatively close vicinity of SNP marker indices in multiple sclerosis compared to control SNPs. We found very high homologies to HERV-K, HCML-ARV, XMRV, Galidia ERV, HERV-H/env62 and XMRV-like mouse endogenous retrovirus mERV-XL. The associated genes (CYP27B1, CD6, CD58, MPV17L2, IL12RB1, CXCR5, PTGER4, TAGAP, TYK2, ICAM3, CD86, GALC, GPR65 as well as the HLA DRB1*1501) are mainly involved in the immune system, but also in vitamin D regulation. The most frequently detected ERV sequences are related to the multiple sclerosis-associated retrovirus, the human immunodeficiency virus 1, HERV-K, and the Simian foamy virus. Our data shows that there is a relation between MS associated SNPs and the number of retroviral elements compared to control. Our data identifies new ERV sequences that have not been associated with MS, so far. PMID:27169423

  15. Mitotic chromosome structure

    International Nuclear Information System (INIS)

    Mounting evidence is compiling linking the physical organizational structure of chromosomes and the nuclear structure to biological function. At the base of the physical organizational structure of both is the concept of loop formation. This implies that physical proximity within chromosomes is provided for otherwise distal genomic regions and thus hierarchically organizing the chromosomes. Together with entropy many experimental observations can be explained with these two concepts. Among the observations that can be explained are the measured physical extent of the chromosomes, their shape, mechanical behavior, the segregation into territories (chromosomal and territories within chromosomes), the results from chromosome conformation capture experiments, as well as linking gene expression to structural organization.

  16. MirSNP, a database of polymorphisms altering miRNA target sites, identifies miRNA-related SNPs in GWAS SNPs and eQTLs

    Directory of Open Access Journals (Sweden)

    Liu Chenxing

    2012-11-01

    Full Text Available Abstract Background Numerous single nucleotide polymorphisms (SNPs associated with complex diseases have been identified by genome-wide association studies (GWAS and expression quantitative trait loci (eQTLs studies. However, few of these SNPs have explicit biological functions. Recent studies indicated that the SNPs within the 3’UTR regions of susceptibility genes could affect complex traits/diseases by affecting the function of miRNAs. These 3’UTR SNPs are functional candidates and therefore of interest to GWAS and eQTL researchers. Description We developed a publicly available online database, MirSNP (http://cmbi.bjmu.edu.cn/mirsnp, which is a collection of human SNPs in predicted miRNA-mRNA binding sites. We identified 414,510 SNPs that might affect miRNA-mRNA binding. Annotations were added to these SNPs to predict whether a SNP within the target site would decrease/break or enhance/create an miRNA-mRNA binding site. By applying MirSNP database to three brain eQTL data sets, we identified four unreported SNPs (rs3087822, rs13042, rs1058381, and rs1058398, which might affect miRNA binding and thus affect the expression of their host genes in the brain. We also applied the MirSNP database to our GWAS for schizophrenia: seven predicted miRNA-related SNPs (p  Conclusion MirSNP could identify the putative miRNA-related SNPs from GWAS and eQTLs researches and provide the direction for subsequent functional researches.

  17. Development of a multiplex PCR assay detecting 52 autosomal SNPs

    DEFF Research Database (Denmark)

    Sanchez Sanchez, Juan Jose; Phillips, C.; Børsting, Claus;

    2006-01-01

    An efficient method that can be used to simultaneously amplify a set of genetic loci across the genome with high reliability can provide a valuable tool for single nucleotide polymorphism (SNP) forensic genotyping. A crucial element is the number of individual biochemical reactions that must be...... performed. The SNPforID consortium (www.snpforid.org) was established in 2003 with the principal goal of developing a SNP-based system of DNA analysis that would have comparable discrimination power and ease of use to those of existing short tandem repeat (STR) based techniques. Here, we describe a strategy...... for amplifying 52 genomic DNA fragments, each containing one SNP, in a single tube, and accurately genotyping the PCR product mixture using two single base extension reactions. This multiplex approach reduces the cost of SNP genotyping and requires as little as 0.5 ng of genomic DNA to detect 52 SNPs...

  18. Fetal chromosome analysis: screening for chromosome disease?

    DEFF Research Database (Denmark)

    Philip, J; Tabor, Ann; Bang, J;

    1983-01-01

    A + B). Pregnant women 35 years of age, women who previously had a chromosomally abnormal child, families with translocation carriers or other heritable chromosomal disease, families where the father was 50 years or more and women in families with a history of Down's syndrome (group A), were...... unbalanced chromosome abnormality in group A (women with elevated risk) is significantly higher than in group B + C (women without elevated risk) (relative risk 2.4). Women with a known familial translocation and women 40 years or more have a relative risk of 5.7 of having an unbalanced chromosome......The aim of the study was to investigate the rationale of the current indications for fetal chromosome analysis. 5372 women had 5423 amniocentesis performed, this group constituting a consecutive sample at the chromosome laboratory, Rigshospitalet, Copenhagen from March 1973 to September 1980 (Group...

  19. Combining functional and linkage disequilibrium information in the selection of tag SNPs

    OpenAIRE

    Sham, PC; Ao, SI; Kwan, JSH; Kao, P; Cheung, F; Fong, PY; Ng, MK

    2007-01-01

    Summary: We have developed an online program, WCLUSTAG, for tag SNP selection that allows the user to specify variable tagging thresholds for different SNPs. Tag SNPs are selected such that a SNP with user-specified tagging threshold C will have a minimum R2 of C with at least one tag SNP. This flexible feature is useful for researchers who wish to prioritize genomic regions or SNPs in an association study. © 2007 Oxford University Press.

  20. Single nucleotide polymorphism discovery of Pinus radiata with chromosome walking PCR method

    Institute of Scientific and Technical Information of China (English)

    Wei LI; Hui LI; Xiaoyang CHEN; Harry WU

    2008-01-01

    In this paper, the basic principle of chromosome walking is presented and we used an actin gene of radiata pine (Pinus radiata) as an example to conduct upstream and downstream chromosome walking for EST sequences. The full genomic sequence (2154 bp) of the actin gene, including promoters 5' UTR, CDS and 3' UTR, was identified by chromosome walking. PCR amplification and DNA band sequencing from 200 unrelated radiata pine trees revealed a total of 21 SNPs for the actin gene, three in the promoter region, 15 in CDS and 4 in 3' UTR. The results of this experiment provide a technical framework for SNPs dis-covery in none coding regions of candidate genes.

  1. FGFR2 risk SNPs confer breast cancer risk by augmenting oestrogen responsiveness.

    Science.gov (United States)

    Campbell, Thomas M; Castro, Mauro A A; de Santiago, Ines; Fletcher, Michael N C; Halim, Silvia; Prathalingam, Radhika; Ponder, Bruce A J; Meyer, Kerstin B

    2016-08-01

    The fibroblast growth factor receptor 2 (FGFR2) locus is consistently the top hit in genome-wide association studies for oestrogen receptor-positive (ER(+)) breast cancer. Yet, its mode of action continues to be controversial. Here, we employ a systems biology approach to demonstrate that signalling via FGFR2 counteracts cell activation by oestrogen. In the presence of oestrogen, the oestrogen receptor (ESR1) regulon (set of ESR1 target genes) is in an active state. However, signalling by FGFR2 is able to reverse the activity of the ESR1 regulon. This effect is seen in multiple distinct FGFR2 signalling model systems, across multiple cells lines and is dependent on the presence of FGFR2. Increased oestrogen exposure has long been associated with an increased risk of breast cancer. We therefore hypothesized that risk variants should reduce FGFR2 expression and subsequent signalling. Indeed, transient transfection experiments assaying the three independent variants of the FGFR2 risk locus (rs2981578, rs35054928 and rs45631563) in their normal chromosomal context show that these single-nucleotide polymorphisms (SNPs) map to transcriptional silencer elements and that, compared with wild type, the risk alleles augment silencer activity. The presence of risk variants results in lower FGFR2 expression and increased oestrogen responsiveness. We thus propose a molecular mechanism by which FGFR2 can confer increased breast cancer risk that is consistent with oestrogen exposure as a major driver of breast cancer risk. Our findings may have implications for the clinical use of FGFR2 inhibitors. PMID:27236187

  2. A microarray system for Y chromosomal and mitochondrial single nucleotide polymorphism analysis in chimpanzee populations.

    Science.gov (United States)

    Andrés, Olga; Rönn, Ann-Charlotte; Bonhomme, Maxime; Kellermann, Thomas; Crouau-Roy, Brigitte; Doxiadis, Gaby; Verschoor, Ernst J; Goossens, Benoît; Domingo-Roura, Xavier; Bruford, Michael W; Bosch, Montserrat; Syvänen, Ann-Christine

    2008-05-01

    Chimpanzee populations are diminishing as a consequence of human activities, and as a result this species is now endangered. In the context of conservation programmes, genetic data can add vital information, for instance on the genetic diversity and structure of threatened populations. Single nucleotide polymorphisms (SNP) are biallelic markers that are widely used in human molecular studies and can be implemented in efficient microarray systems. This technology offers the potential of robust, multiplexed SNP genotyping at low reagent cost in other organisms than humans, but it is not commonly used yet in wild population studies. Here, we describe the characterization of new SNPs in Y-chromosomal intronic regions in chimpanzees and also identify SNPs from mitochondrial genes, with the aim of developing a microarray system that permits the simultaneous study of both paternal and maternal lineages. Our system consists of 42 SNPs for the Y chromosome and 45 SNPs for the mitochondrial genome. We demonstrate the applicability of this microarray in a captive population where genotypes accurately reflected its large pedigree. Two wild-living populations were also analysed and the results show that the microarray will be a useful tool alongside microsatellite markers, since it supplies complementary information about population structure and ecology. SNP genotyping using microarray technology, therefore, is a promising approach and may become an essential tool in conservation genetics to help in the management and study of captive and wild-living populations. Moreover, microarrays that combine SNPs from different genomic regions could replace microsatellite typing in the future. PMID:21585830

  3. Chromosome painting in plants.

    NARCIS (Netherlands)

    Schubert, I.; Fransz, P.F.; Fuchs, J.; Jong, de J.H.

    2001-01-01

    The current 'state-of-art' as to chromosome painting in plants is reviewed. We define different situations described as painting so far: i) Genomic in situ hybridisation (GISH) with total genomic DNA to distinguish alien chromosomes on the basis of divergent dispersed repeats, ii) 'Chromosomal in si

  4. Common non-synonymous SNPs associated with breast cancer susceptibility

    DEFF Research Database (Denmark)

    Milne, Roger L; Burwinkel, Barbara; Michailidou, Kyriaki;

    2014-01-01

    SNPs: ATXN7-K264R at 3p21 [rs1053338, per allele OR = 1.07, 95% confidence interval (CI) = 1.04-1.10, P = 2.9 × 10(-6)], AKAP9-M463I at 7q21 (rs6964587, OR = 1.05, 95% CI = 1.03-1.07, P = 1.7 × 10(-6)) and NEK10-L513S at 3p24 (rs10510592, OR = 1.10, 95% CI = 1.07-1.12, P = 5.1 × 10(-17)). The first two...... associations reached genome-wide statistical significance in a combined analysis of available data, including independent data from nine genome-wide association studies (GWASs): for ATXN7-K264R, OR = 1.07 (95% CI = 1.05-1.10, P = 1.0 × 10(-8)); for AKAP9-M463I, OR = 1.05 (95% CI = 1.04-1.07, P = 2.0 × 10...

  5. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits

    OpenAIRE

    Geísa Pinheiro Paes; José Marcelo Soriano Viana; Fabyano Fonseca e Silva; Gabriel Borges Mundim

    2016-01-01

    Abstract The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kerne...

  6. Targeted Metabolic Engineering Guided by Computational Analysis of Single-Nucleotide Polymorphisms (SNPs)

    DEFF Research Database (Denmark)

    Udatha, D B R K Gupta; Rasmussen, Simon; Sicheritz-Pontén, Thomas;

    2013-01-01

    The non-synonymous SNPs, the so-called non-silent SNPs, which are single-nucleotide variations in the coding regions that give "birth" to amino acid mutations, are often involved in the modulation of protein function. Understanding the effect of individual amino acid mutations on a protein...

  7. SNPs in PPARG associate with type 2 diabetes and interact with physical activity

    DEFF Research Database (Denmark)

    Oskari Kilpeläinen, Tuomas; Lakka, Timo A; Laaksonen, David E;

    2008-01-01

    To study the associations of seven single-nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptor gamma (PPARG) gene with the conversion from impaired glucose tolerance (IGT) to type 2 diabetes (T2D), and the interactions of the SNPs with physical activity (PA)....

  8. Data mining of public SNP databases for the selection of intragenic SNPs

    NARCIS (Netherlands)

    Aerts, J.; Wetzels, Y.; Cohen, N.; Aerssens, J.

    2002-01-01

    Different strategies to search public single nucleotide polymorphism (SNP) databases for intragenic SNPs were evaluated. First, we assembled a strategy to annotate SNPs onto candidate genes based on a BLAST search of public SNP databases (Intragenic SNP Annotation by BLAST, ISAB). Only BLAST hits th

  9. CsSNP: A Web-Based Tool for the Detecting of Comparative Segments SNPs.

    Science.gov (United States)

    Wang, Yi; Wang, Shuangshuang; Zhou, Dongjie; Yang, Shuai; Xu, Yongchao; Yang, Chao; Yang, Long

    2016-07-01

    SNP (single nucleotide polymorphism) is a popular tool for the study of genetic diversity, evolution, and other areas. Therefore, it is necessary to develop a convenient, utility, robust, rapid, and open source detecting-SNP tool for all researchers. Since the detection of SNPs needs special software and series steps including alignment, detection, analysis and present, the study of SNPs is limited for nonprofessional users. CsSNP (Comparative segments SNP, http://biodb.sdau.edu.cn/cssnp/ ) is a freely available web tool based on the Blat, Blast, and Perl programs to detect comparative segments SNPs and to show the detail information of SNPs. The results are filtered and presented in the statistics figure and a Gbrowse map. This platform contains the reference genomic sequences and coding sequences of 60 plant species, and also provides new opportunities for the users to detect SNPs easily. CsSNP is provided a convenient tool for nonprofessional users to find comparative segments SNPs in their own sequences, and give the users the information and the analysis of SNPs, and display these data in a dynamic map. It provides a new method to detect SNPs and may accelerate related studies. PMID:27347883

  10. Application of SNPs for population genetics of nonmodel organisms: new opportunities and challenges

    DEFF Research Database (Denmark)

    Helyar, S.J.; Hansen, Jakob Hemmer; Bekkevold, Dorte;

    2011-01-01

    Recent improvements in the speed, cost and accuracy of next generation sequencing are revolutionizing the discovery of single nucleotide polymorphisms (SNPs). SNPs are increasingly being used as an addition to the molecular ecology toolkit in nonmodel organisms, but their efficient use remains ch...... population genetic analysis of SNPs in nonmodel taxa, focusing specifically on some of the most commonly applied methods.......Recent improvements in the speed, cost and accuracy of next generation sequencing are revolutionizing the discovery of single nucleotide polymorphisms (SNPs). SNPs are increasingly being used as an addition to the molecular ecology toolkit in nonmodel organisms, but their efficient use remains...... challenging. Here, we discuss common issues when employing SNP markers, including the high numbers of markers typically employed, the effects of ascertainment bias and the inclusion of nonneutral loci in a marker panel. We provide a critique of considerations specifically associated with the application and...

  11. SNPsnap: a Web-based tool for identification and annotation of matched SNPs

    DEFF Research Database (Denmark)

    Pers, Tune Hannes; Timshel, Pascal; Hirschhorn, Joel N.

    2015-01-01

    Summary : An important computational step following genome-wide association studies (GWAS) is to assess whether disease or trait-associated single-nucleotide polymorphisms (SNPs) enrich for particular biological annotations. SNP-based enrichment analysis needs to account for biases such as co......-localization of GWAS signals to gene-dense and high linkage disequilibrium (LD) regions, and correlations of gene size, location and function. The SNPsnap Web server enables SNP-based enrichment analysis by providing matched sets of SNPs that can be used to calibrate background expectations. Specifically, SNPsnap...... efficiently identifies sets of randomly drawn SNPs that are matched to a set of query SNPs based on allele frequency, number of SNPs in LD, distance to nearest gene and gene density. Availability and implementation : SNPsnap server is available at http://www.broadinstitute.org/mpg/snpsnap/. Contact: joelh...

  12. Genotyping of 75 SNPs using arrays for individual identification in five population groups.

    Science.gov (United States)

    Hwa, Hsiao-Lin; Wu, Lawrence Shih Hsin; Lin, Chun-Yen; Huang, Tsun-Ying; Yin, Hsiang-I; Tseng, Li-Hui; Lee, James Chun-I

    2016-01-01

    Single nucleotide polymorphism (SNP) typing offers promise to forensic genetics. Various strategies and panels for analyzing SNP markers for individual identification have been published. However, the best panels with fewer identity SNPs for all major population groups are still under discussion. This study aimed to find more autosomal SNPs with high heterozygosity for individual identification among Asian populations. Ninety-six autosomal SNPs of 502 DNA samples from unrelated individuals of five population groups (208 Taiwanese Han, 83 Filipinos, 62 Thais, 69 Indonesians, and 80 individuals with European, Near Eastern, or South Asian ancestry) were analyzed using arrays in an initial screening, and 75 SNPs (group A, 46 newly selected SNPs; groups B, 29 SNPs based on a previous SNP panel) were selected for further statistical analyses. Some SNPs with high heterozygosity from Asian populations were identified. The combined random match probability of the best 40 and 45 SNPs was between 3.16 × 10(-17) and 7.75 × 10(-17) and between 2.33 × 10(-19) and 7.00 × 10(-19), respectively, in all five populations. These loci offer comparable power to short tandem repeats (STRs) for routine forensic profiling. In this study, we demonstrated the population genetic characteristics and forensic parameters of 75 SNPs with high heterozygosity from five population groups. This SNPs panel can provide valuable genotypic information and can be helpful in forensic casework for individual identification among these populations. PMID:26297200

  13. Effective selection of informative SNPs and classification on the HapMap genotype data

    Directory of Open Access Journals (Sweden)

    Wang Lipo

    2007-12-01

    Full Text Available Abstract Background Since the single nucleotide polymorphisms (SNPs are genetic variations which determine the difference between any two unrelated individuals, the SNPs can be used to identify the correct source population of an individual. For efficient population identification with the HapMap genotype data, as few informative SNPs as possible are required from the original 4 million SNPs. Recently, Park et al. (2006 adopted the nearest shrunken centroid method to classify the three populations, i.e., Utah residents with ancestry from Northern and Western Europe (CEU, Yoruba in Ibadan, Nigeria in West Africa (YRI, and Han Chinese in Beijing together with Japanese in Tokyo (CHB+JPT, from which 100,736 SNPs were obtained and the top 82 SNPs could completely classify the three populations. Results In this paper, we propose to first rank each feature (SNP using a ranking measure, i.e., a modified t-test or F-statistics. Then from the ranking list, we form different feature subsets by sequentially choosing different numbers of features (e.g., 1, 2, 3, ..., 100. with top ranking values, train and test them by a classifier, e.g., the support vector machine (SVM, thereby finding one subset which has the highest classification accuracy. Compared to the classification method of Park et al., we obtain a better result, i.e., good classification of the 3 populations using on average 64 SNPs. Conclusion Experimental results show that the both of the modified t-test and F-statistics method are very effective in ranking SNPs about their classification capabilities. Combined with the SVM classifier, a desirable feature subset (with the minimum size and most informativeness can be quickly found in the greedy manner after ranking all SNPs. Our method is able to identify a very small number of important SNPs that can determine the populations of individuals.

  14. Overview of some projects of SNPS for global space communication

    International Nuclear Information System (INIS)

    In this presentation we focused on three variants of prospective concepts of SNPS. They are intended to solve tasks of global space communication (GSC) as nearest future tasks in space. Modern concepts of the application of power technology in space believe in using an onboard source of energy for maintenance of self-transportation of the vehicle into geostationary orbit (GSO). There are three more prospective systems as follows: gas cooled nuclear reactor with hybrid thermal engine and machine power converter; nuclear reactor cooled by liquid metal and with a thermoelectric power generating system; nuclear reactor with Li cooling and a thermionic and thermoelectric power generator on board. The choice of a concept must fit strong requirements such as: space nuclear power unit is aimed to be used in a powerful mission; space power unit must be able to maintain the dual - mode regime of vehicle operation (self - transportation and long life in geosynchronous orbit [GEO]); nuclear rector of unit must be safety and it must be designed in such a way that it will ensure minimum size of the complete system; the elements of the considered technology can be used for the creation of NPPI and with other sources of heat (for example, radioisotope); the degree of technical and technological readiness of units of the thermal and power circuit of installation is estimated to be high and is defined by a number of technological developments in air, space and nuclear branches; nuclear reactor and heat transfer equipment should work in a normal mode, which can be very reliably confirmed for other high-temperature nuclear systems. Considering these concepts we practically consider one of possible strategy of developing of complex system of nuclear power engineering. It is the strategy of step-by-step development of space engineering with real application of them in commercial, scientific and other powerful missions in the nearest and deep space. As starting point of this activity is

  15. LDGIdb: a database of gene interactions inferred from long-range strong linkage disequilibrium between pairs of SNPs

    Directory of Open Access Journals (Sweden)

    Wang Ming-Chih

    2012-05-01

    Full Text Available Abstract Background Complex human diseases may be associated with many gene interactions. Gene interactions take several different forms and it is difficult to identify all of the interactions that are potentially associated with human diseases. One approach that may fill this knowledge gap is to infer previously unknown gene interactions via identification of non-physical linkages between different mutations (or single nucleotide polymorphisms, SNPs to avoid hitchhiking effect or lack of recombination. Strong non-physical SNP linkages are considered to be an indication of biological (gene interactions. These interactions can be physical protein interactions, regulatory interactions, functional compensation/antagonization or many other forms of interactions. Previous studies have shown that mutations in different genes can be linked to the same disorders. Therefore, non-physical SNP linkages, coupled with knowledge of SNP-disease associations may shed more light on the role of gene interactions in human disorders. A user-friendly web resource that integrates information about non-physical SNP linkages, gene annotations, SNP information, and SNP-disease associations may thus be a good reference for biomedical research. Findings Here we extracted the SNPs located within the promoter or exonic regions of protein-coding genes from the HapMap database to construct a database named the Linkage-Disequilibrium-based Gene Interaction database (LDGIdb. The database stores 646,203 potential human gene interactions, which are potential interactions inferred from SNP pairs that are subject to long-range strong linkage disequilibrium (LD, or non-physical linkages. To minimize the possibility of hitchhiking, SNP pairs inferred to be non-physically linked were required to be located in different chromosomes or in different LD blocks of the same chromosomes. According to the genomic locations of the involved SNPs (i.e., promoter, untranslated region (UTR and

  16. An examination of clinical differences between carriers and non-carriers of chromosome 8q24 risk alleles in a New Zealand Caucasian population with prostate cancer.

    Science.gov (United States)

    Bishop, Karen S; Han, Dug Yeo; Karunasinghe, Nishi; Goudie, Megan; Masters, Jonathan G; Ferguson, Lynnette R

    2016-01-01

    Background. Prostate cancer makes up approximately 15% of all cancers diagnosed in men in developed nations and approximately 4% of cases in developing nations. Although it is clear that prostate cancer has a genetic component and single nucleotide polymorphisms (SNPs) can contribute to prostate cancer risk, detecting associations is difficult in multi-factorial diseases, as environmental and lifestyle factors also play a role. In this study, specific clinical characteristics, environmental factors and genetic risk factors were assessed for interaction with prostate cancer. Methods. A total of 489 prostate cancer cases and 427 healthy controls were genotyped for SNPs found on chromosome 8q24 and a genetic risk score was calculated. In addition the SNPs were tested for an association with a number of clinical and environmental factors. Results. Age and tobacco use were positively associated, whilst alcohol consumption was negatively associated with prostate cancer risk. The following SNPs found on chromosome 8q24 were statistically significantly associated with prostate cancer: rs10086908, rs16901979; rs1447295and rs4242382. No association between Gleason score and smoking status, or between Gleason score and genotype were detected. Conclusion. A genetic risk score was calculated based on the 15 SNPs tested and found to be significantly associated with prostate cancer risk. Smoking significantly contributed to the risk of developing prostate cancer, and this risk was further increased by the presence of four SNPs in the 8q24 chromosomal region. PMID:26966665

  17. Chimpanzee chromosome 12 is homologous to human chromosome 2q

    Energy Technology Data Exchange (ETDEWEB)

    Sun, N. C.; Sun, C. R.Y.; Ho, T.

    1977-01-01

    Most of the 46 human chromosomes find their counterparts in the 48 chimpanzee chromosomes except for chromosome 2 which has been hypothesized to have been derived from a centric fusion of two chimpanzee acrocentric chromosomes. These two chromosomes correspond to the human chromosomes 2p and 2g. This conclusion is based primarily on chromosome banding techniques, and the somatic cell hybridization technique has also been used. (HLW)

  18. A comparison of SNPs and microsatellites as linkage mapping markers: lessons from the zebra finch (Taeniopygia guttata

    Directory of Open Access Journals (Sweden)

    Birkhead Tim R

    2010-04-01

    Full Text Available Abstract Background Genetic linkage maps are essential tools when searching for quantitative trait loci (QTL. To maximize genome coverage and provide an evenly spaced marker distribution a combination of different types of genetic marker are sometimes used. In this study we created linkage maps of four zebra finch (Taeniopygia guttata chromosomes (1, 1A, 2 and 9 using two types of marker, Single Nucleotide Polymorphisms (SNPs and microsatellites. To assess the effectiveness and accuracy of each kind of marker we compared maps built with each marker type separately and with both types of marker combined. Linkage map marker order was validated by making comparisons to the assembled zebra finch genome sequence. Results We showed that marker order was less reliable and linkage map lengths were inflated for microsatellite maps relative to SNP maps, apparently due to differing error rates between the two types of marker. Guidelines on how to minimise the effects of error are provided. In particular, we show that when combining both types of marker the conventional process of building linkage maps, whereby the most informative markers are added to the map first, has to be modified in order to improve map accuracy. Conclusions When using multiple types and large numbers of markers to create dense linkage maps, the least error prone loci (SNPs rather than the most informative should be used to create framework maps before the addition of other potentially more error prone markers (microsatellites. This raises questions about the accuracy of marker order and predicted recombination rates in previous microsatellite linkage maps which were created using the conventional building process, however, provided suitable error detection strategies are followed microsatellite-based maps can continue to be regarded as reasonably reliable.

  19. X-chromosome Forkhead Box P3 polymorphisms associate with atopy in girls in three Dutch birth cohorts

    NARCIS (Netherlands)

    Bottema, R. W. B.; Kerkhof, M.; Reijmerink, N. E.; Koppelman, G. H.; Thijs, C.; Stelma, F. F.; Smit, H. A.; Brunekreef, B.; van Schayck, C. P.; Postma, D. S.

    2010-01-01

    P>Background: The Forkhead Box P3 (FOXP3) gene, located on the X-chromosome, encodes a transcription factor that directs T cells toward a regulatory phenotype. Regulatory T cells may suppress development of atopy. We evaluated whether single-nucleotide polymorphisms (SNPs) of FOXP3 are associated wi

  20. Understanding the Y chromosome variation in Korea--relevance of combined haplogroup and haplotype analyses.

    Science.gov (United States)

    Park, Myung Jin; Lee, Hwan Young; Yang, Woo Ick; Shin, Kyoung-Jin

    2012-07-01

    We performed a molecular characterization of Korean Y-chromosomal haplogroups using a combination of Y-chromosomal single nucleotide polymorphisms (Y-SNPs) and Y-chromosomal short tandem repeats (Y-STRs). In a test using DNA samples from 706 Korean males, a total of 19 different haplogroups were identified by 26 Y-SNPs including the newly redefined markers (PK4, KL2, and P164) in haplogroup O. When genotyping the SNPs, phylogenetic nonequivalence was found between SNPs M117 and M133, which define haplogroup O3a3c1 (O3a2c1a according to the updated tree of haplogroup O by Yan et al. (European Journal of Human Genetics 19:1013-1015, 2011)), suggesting that the position of the M133 marker should be corrected. We have shown that the haplotypes consisted of DYS392, DYS393, DYS437, DYS438, DYS448, and DYS388 loci, which exhibit a relatively lower mutation rate, can preserve phylogenetic information and hence can be used to roughly distinguish Y-chromosome haplogroups, whereas more rapidly mutating Y-STRs such as DYS449 and DYS458 are useful for differentiating male lineages. However, at the relatively rapidly mutating DYS447, DYS449, DYS458, and DYS464 loci, unusually short alleles and intermediate alleles with common sequence structures are informative for elucidating the substructure within the context of a particular haplogroup. In addition, some deletion mutations in the DYS385 flanking region and the null allele at DYS448 were associated with a single haplogroup background. These high-resolution haplogroup and haplotype data will improve our understanding of regional Y-chromosome variation or recent migration routes and will also help to infer haplogroup background or common ancestry. PMID:22569803

  1. Screening and Evaluation of Deleterious SNPs in APOE Gene of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Tariq Ahmad Masoodi

    2012-01-01

    Full Text Available Introduction. Apolipoprotein E (APOE is an important risk factor for Alzheimer’s disease (AD and is present in 30–50% of patients who develop late-onset AD. Several single-nucleotide polymorphisms (SNPs are present in APOE gene which act as the biomarkers for exploring the genetic basis of this disease. The objective of this study is to identify deleterious nsSNPs associated with APOE gene. Methods. The SNPs were retrieved from dbSNP. Using I-Mutant, protein stability change was calculated. The potentially functional nonsynonymous (ns SNPs and their effect on protein was predicted by PolyPhen and SIFT, respectively. FASTSNP was used for functional analysis and estimation of risk score. The functional impact on the APOE protein was evaluated by using Swiss PDB viewer and NOMAD-Ref server. Results. Six nsSNPs were found to be least stable by I-Mutant 2.0 with DDG value of >−1.0. Four nsSNPs showed a highly deleterious tolerance index score of 0.00. Nine nsSNPs were found to be probably damaging with position-specific independent counts (PSICs score of ≥2.0. Seven nsSNPs were found to be highly polymorphic with a risk score of 3-4. The total energies and root-mean-square deviation (RMSD values were higher for three mutant-type structures compared to the native modeled structure. Conclusion. We concluded that three nsSNPs, namely, rs11542041, rs11542040, and rs11542034, to be potentially functional polymorphic.

  2. Identifying Liver Cancer-Related Enhancer SNPs by Integrating GWAS and Histone Modification ChIP-seq Data

    Directory of Open Access Journals (Sweden)

    Tianjiao Zhang

    2016-01-01

    Full Text Available Many disease-related single nucleotide polymorphisms (SNPs have been inferred from genome-wide association studies (GWAS in recent years. Numerous studies have shown that some SNPs located in protein-coding regions are associated with numerous diseases by affecting gene expression. However, in noncoding regions, the mechanism of how SNPs contribute to disease susceptibility remains unclear. Enhancer elements are functional segments of DNA located in noncoding regions that play an important role in regulating gene expression. The SNPs located in enhancer elements may affect gene expression and lead to disease. We presented a method for identifying liver cancer-related enhancer SNPs through integrating GWAS and histone modification ChIP-seq data. We identified 22 liver cancer-related enhancer SNPs, 9 of which were regulatory SNPs involved in distal transcriptional regulation. The results highlight that these enhancer SNPs may play important roles in liver cancer.

  3. Identifying Liver Cancer-Related Enhancer SNPs by Integrating GWAS and Histone Modification ChIP-seq Data

    Science.gov (United States)

    Hu, Yang; Wu, Xiaoliang; Ma, Rui

    2016-01-01

    Many disease-related single nucleotide polymorphisms (SNPs) have been inferred from genome-wide association studies (GWAS) in recent years. Numerous studies have shown that some SNPs located in protein-coding regions are associated with numerous diseases by affecting gene expression. However, in noncoding regions, the mechanism of how SNPs contribute to disease susceptibility remains unclear. Enhancer elements are functional segments of DNA located in noncoding regions that play an important role in regulating gene expression. The SNPs located in enhancer elements may affect gene expression and lead to disease. We presented a method for identifying liver cancer-related enhancer SNPs through integrating GWAS and histone modification ChIP-seq data. We identified 22 liver cancer-related enhancer SNPs, 9 of which were regulatory SNPs involved in distal transcriptional regulation. The results highlight that these enhancer SNPs may play important roles in liver cancer. PMID:27429976

  4. Single nucleotide polymorphisms (SNPs) that map to gaps in the human SNP map

    OpenAIRE

    Tsui, Circe; Coleman, Laura E.; Griffith, Jacqulyn L.; Bennett, E. Andrew; Goodson, Summer G.; Scott, Jason D.; Pittard, W. Stephen; Devine, Scott E.

    2003-01-01

    An international effort is underway to generate a comprehensive haplotype map (HapMap) of the human genome represented by an estimated 300 000 to 1 million ‘tag’ single nucleotide polymorphisms (SNPs). Our analysis indicates that the current human SNP map is not sufficiently dense to support the HapMap project. For example, 24.6% of the genome currently lacks SNPs at the minimal density and spacing that would be required to construct even a conservative tag SNP map containing 300 000 SNPs. In...

  5. Association of SNPs and haplotypes in GABA(A) receptor beta(2) gene with schizophrenia

    Institute of Scientific and Technical Information of China (English)

    WSLau; CFXuan; ZChan; CFFeng; GYHe; LCao; ZCLiu; HLuan; QMXue

    2005-01-01

    Disturbances in GABAergic system have been observed in schizophrenics.(1-3) In the present study, population association analysis was performed on 19 SNPs in the alpha(l), beta(2), gamma(2), epsilon and pi subunit genes of GABA(A) receptor. Five SNPs in GABRB2, namely B217G1584T, rs1816071, rs194072, rs252944 and rs187269,were found to be significantly associated, and their haplotypes in linkage disequilibrium, with schizophrenia. This represents the first report on any disease association of SNPs in the human GABA(A) receptor genes, and focuses attention on the GABAergic hypothesis of schizophrenia etiology.(3,4)

  6. Improved Resolution Haplogroup G Phylogeny in the Y Chromosome, Revealed by a Set of Newly Characterized SNPs

    OpenAIRE

    Sims, Lynn M.; Garvey, Dennis; Ballantyne, Jack

    2009-01-01

    Background Y-SNP haplogroup G (hgG), defined by Y-SNP marker M201, is relatively uncommon in the United States general population, with only 8 additional sub-markers characterized. Many of the previously described eight sub-markers are either very rare (2–4%) or do not distinguish between major populations within this hg. In fact, prior to the current study, only 2% of our reference Caucasian population belonged to hgG and all of these individuals were in sub-haplogroup G2a, defined by P15. A...

  7. The plasmacytoma resistance gene, Pctr2, delays the onset of tumorigenesis and resides in the telomeric region of chromosome 4.

    Science.gov (United States)

    Mock, B A; Hartley, J; Le Tissier, P; Wax, J S; Potter, M

    1997-11-15

    Mouse plasmacytomas share pathogenetic features in common with both multiple myeloma and Burkitt's lymphoma in humans. Susceptibility to plasmacytoma induction by intraperitoneal pristane in mice is controlled by multiple genes. At least two of these genes reside on mouse chromosome 4 in regions of the genome sharing linkage homology with human chromosomes 9p21, 1p32, and 1p36. A series of congenic strains recombinant for regions of mouse chromosome 4 in the vicinity of the Pctr2 predisposition locus were created and typed for their tumor susceptibility/resistance phenotypes. These strains were derived by introgressively backcrossing alleles from resistant DBA/2 mice onto the susceptible BALB/cAnPt background. Six resistant and two susceptible strains were allelotyped for 10 genes and 49 random DNA markers to identify the smallest region of overlap in the resistant strains. These studies have determined that the Pctr2 locus resides in either a 500-kb interval proximal to Nppa, or in a 1- to 2-centiMorgan (cM) interval distal to Nppa. In these congenic strain analyses, the Nppa and Fv1 loci, in addition to genes within about 1 cM of these loci, have been excluded as candidates for the Pctr2 locus. A relevant locus that may reside in this interval is Rep2; it is associated with the efficiency of repairing X-ray induced DNA damage sustained during the G2 phase of the mitotic cycle. The Pctr2 locus acts in a codominant fashion. F1 hybrids between resistant and susceptible congenic strains exhibit a reduced tumor incidence and a significant delay in the onset of tumorigenesis. Identification and eventual cloning of the Pctr2 locus may assist in the identification of genes involved in many types of cancer showing aberrations in human chromosome 1p36. PMID:9354679

  8. Rapid De Novo Evolution of X Chromosome Dosage Compensation in Silene latifolia, a Plant with Young Sex Chromosomes

    Science.gov (United States)

    Deschamps, Clothilde; Mousset, Sylvain; Widmer, Alex; Marais, Gabriel A. B.

    2012-01-01

    Silene latifolia is a dioecious plant with heteromorphic sex chromosomes that have originated only ∼10 million years ago and is a promising model organism to study sex chromosome evolution in plants. Previous work suggests that S. latifolia XY chromosomes have gradually stopped recombining and the Y chromosome is undergoing degeneration as in animal sex chromosomes. However, this work has been limited by the paucity of sex-linked genes available. Here, we used 35 Gb of RNA-seq data from multiple males (XY) and females (XX) of an S. latifolia inbred line to detect sex-linked SNPs and identified more than 1,700 sex-linked contigs (with X-linked and Y-linked alleles). Analyses using known sex-linked and autosomal genes, together with simulations indicate that these newly identified sex-linked contigs are reliable. Using read numbers, we then estimated expression levels of X-linked and Y-linked alleles in males and found an overall trend of reduced expression of Y-linked alleles, consistent with a widespread ongoing degeneration of the S. latifolia Y chromosome. By comparing expression intensities of X-linked alleles in males and females, we found that X-linked allele expression increases as Y-linked allele expression decreases in males, which makes expression of sex-linked contigs similar in both sexes. This phenomenon is known as dosage compensation and has so far only been observed in evolutionary old animal sex chromosome systems. Our results suggest that dosage compensation has evolved in plants and that it can quickly evolve de novo after the origin of sex chromosomes. PMID:22529744

  9. Optimisation and validation of methods to assess single nucleotide polymorphisms (SNPs) in archival histological material

    DEFF Research Database (Denmark)

    Andreassen, C N; Sørensen, Flemming Brandt; Overgaard, J;

    2004-01-01

    only archival specimens are available. This study was conducted to validate protocols optimised for assessment of SNPs based on paraffin embedded, formalin fixed tissue samples. PATIENTS AND METHODS: In 137 breast cancer patients, three TGFB1 SNPs were assessed based on archival histological specimens....... In 37 of these patients, the SNPs were also assessed using cultured fibroblasts and the assays were validated by direct comparison of the results. From the remaining 100 patients, only archival material was available. In these patients, the existence of a genetic linkage pattern between the assessed...... precipitation). RESULTS: Assessment of SNPs based on archival histological material is encumbered by a number of obstacles and pitfalls. However, these can be widely overcome by careful optimisation of the methods used for sample selection, DNA extraction and PCR. Within 130 samples that fulfil the criteria...

  10. Genetic relationship between five psychiatric disorders estimated from genome-wide SNPs

    DEFF Research Database (Denmark)

    Lee, S Hong; Ripke, Stephan; Neale, Benjamin M;

    2013-01-01

    and controls in schizophrenia, bipolar disorder, major depressive disorder, autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD). We apply univariate and bivariate methods for the estimation of genetic variation within and covariation between disorders. SNPs explained 17...

  11. INSIG2 SNPS ASSOCIATED WITH OBESITY & GLUCOSE HOMEOSTASIS TRAITS IN HISPANICS: THE IRAS FAMILY STUDY

    OpenAIRE

    Talbert, Matthew E.; Langefeld, Carl D.; Ziegler, Julie; Haffner, Steven M.; Norris, Jill M.; Donald W Bowden

    2009-01-01

    The genome-wide association study by Herbert and colleagues identified the INSIG2 single nucleotide polymorphism (SNP) rs7566605 as contributing to increased BMI in ethnically distinct cohorts. The present study sought to further clarify by testing whether SNPs of INSIG2 influenced quantitative adiposity or glucose homeostasis traits in Hispanics of the Insulin Resistance Atherosclerosis Family Study (IRASFS). Using a tagging SNP approach, rs7566605 and 31 additional SNPs were genotyped in 14...

  12. Association of obesity risk SNPs in PCSK1 with insulin sensitivity and proinsulin conversion

    OpenAIRE

    Häring Hans-Ulrich; Staiger Harald; Stefan Norbert; Machicao Fausto; Thamer Claus; Ketterer Caroline; Schäfer Silke A; Haupt Axel; Heni Martin; Fritsche Andreas

    2010-01-01

    Abstract Background Prohormone convertase 1 is involved in maturation of peptides. Rare mutations in gene PCSK1, encoding this enzyme, cause childhood obesity and abnormal glucose homeostasis with elevated proinsulin concentrations. Common single nucleotide polymorphisms (SNPs) within this gene, rs6232 and rs6235, are associated with obesity. We studied whether these SNPs influence the prediabetic traits insulin resistance, β-cell dysfunction, or glucose intolerance. Methods We genotyped 1498...

  13. No Association of SNPs in One-Carbon Metabolism Genes with Prostate Cancer Risk

    OpenAIRE

    Stevens, Victoria L; Rodriguez, Carmen; Sun, Juzhong; Talbot, Jeffrey T.; Michael J Thun; Eugenia E Calle

    2008-01-01

    One-carbon metabolism mediates the inter-conversion of folates for the synthesis of precursors used in DNA synthesis, repair and methylation. Inadequate folate nutrition or compromised metabolism can disrupt these processes and facilitate carcinogenesis. In this study, we investigated associations of 39 candidate SNPs in nine one-carbon metabolism genes with risk of prostate cancer using 1,144 cases and 1,144 controls from the Cancer Prevention Study-II Nutrition Cohort. None of these SNPs we...

  14. Genetic association of SNPs in the FTO gene and predisposition to obesity in Malaysian Malays

    OpenAIRE

    Y.D. Apalasamy; Ming, M.F.; Rampal, S; Bulgiba, A.; Mohamed, Z

    2012-01-01

    The common variants in the fat mass- and obesity-associated (FTO) gene have been previously found to be associated with obesity in various adult populations. The objective of the present study was to investigate whether the single nucleotide polymorphisms (SNPs) and linkage disequilibrium (LD) blocks in various regions of the FTO gene are associated with predisposition to obesity in Malaysian Malays. Thirty-one FTO SNPs were genotyped in 587 (158 obese and 429 non-obese) Malaysian Malay subje...

  15. Chronic Myelomonocytic Leukemia with t(3;9)(p21;p13) as a Sole Abnormal Appearance: One Case Report

    Institute of Scientific and Technical Information of China (English)

    Ji-hong ZHANG; Li-jun GUAN; Yun-xiu WANG; Ying-chun ZHENG; Nan ZHANG; Hai-xia TONG

    2010-01-01

    @@ Introduction Chronic myelomonocytic leukemia, (CMML) is a clinically rare chronic myeloid leukemia, with an incidence rate of about 1-2/100,000/year, and the age of the predominant cases is over 60 years. The median age of onset is 65-70 years, and the ratio of the incidence between male and female is about 1.5 : 3.1.

  16. Verification of SNPs Associated with Growth Traits in Two Populations of Farmed Atlantic Salmon

    Directory of Open Access Journals (Sweden)

    Hsin Y. Tsai

    2015-12-01

    Full Text Available Understanding the relationship between genetic variants and traits of economic importance in aquaculture species is pertinent to selective breeding programmes. High-throughput sequencing technologies have enabled the discovery of large numbers of SNPs in Atlantic salmon, and high density SNP arrays now exist. A previous genome-wide association study (GWAS using a high density SNP array (132K SNPs has revealed the polygenic nature of early growth traits in salmon, but has also identified candidate SNPs showing suggestive associations with these traits. The aim of this study was to test the association of the candidate growth-associated SNPs in a separate population of farmed Atlantic salmon to verify their effects. Identifying SNP-trait associations in two populations provides evidence that the associations are true and robust. Using a large cohort (N = 1152, we successfully genotyped eight candidate SNPs from the previous GWAS, two of which were significantly associated with several growth and fillet traits measured at harvest. The genes proximal to these SNPs were identified by alignment to the salmon reference genome and are discussed in the context of their potential role in underpinning genetic variation in salmon growth.

  17. Different evolutionary patterns of SNPs between domains and unassigned regions in human protein-coding sequences.

    Science.gov (United States)

    Pang, Erli; Wu, Xiaomei; Lin, Kui

    2016-06-01

    Protein evolution plays an important role in the evolution of each genome. Because of their functional nature, in general, most of their parts or sites are differently constrained selectively, particularly by purifying selection. Most previous studies on protein evolution considered individual proteins in their entirety or compared protein-coding sequences with non-coding sequences. Less attention has been paid to the evolution of different parts within each protein of a given genome. To this end, based on PfamA annotation of all human proteins, each protein sequence can be split into two parts: domains or unassigned regions. Using this rationale, single nucleotide polymorphisms (SNPs) in protein-coding sequences from the 1000 Genomes Project were mapped according to two classifications: SNPs occurring within protein domains and those within unassigned regions. With these classifications, we found: the density of synonymous SNPs within domains is significantly greater than that of synonymous SNPs within unassigned regions; however, the density of non-synonymous SNPs shows the opposite pattern. We also found there are signatures of purifying selection on both the domain and unassigned regions. Furthermore, the selective strength on domains is significantly greater than that on unassigned regions. In addition, among all of the human protein sequences, there are 117 PfamA domains in which no SNPs are found. Our results highlight an important aspect of protein domains and may contribute to our understanding of protein evolution. PMID:26833483

  18. Bioinformatics Analysis for Coding SNPs of the HLADQA1 Gene Involved in Susceptibility to Cervical Cancer

    Institute of Scientific and Technical Information of China (English)

    Yanyun Li; Jun Xing; Linsheng Zhao; Yanni Li; Yuchuan Wang; Weiming Zhang

    2006-01-01

    OBJECTIVE To analyze coding SNPs of the HLA-DQA1 gene involved in susceptibility for cervical cancer by a bioinformatics approach, and to choose some SNPs that may have an association with cervical cancer.METHODS By a SNPper tool we extracted SNPs from a public database (dbSNP), exporting them in FASTA formats suitable for subsequent use.Then we used PARSESNP as a tool for the analysis of the cSNPs.RESULTS In the cSNPs of the HLA-DQA1 gene, we find that rs9272693and rs9272703, are made up of missense mutations which convert a codon for one amino acid into a codon for a different amino acid. We chose a PSSM Difference >10 as a lower level for the scores of changes predicted to be deldterious.CONCLUSION We used a bioinformatics approach for cSNPs analysis of the HLA-DQA1 gene. This method can select the variants in a conserved region, and give a PSSM Difference score. But the results need to be verified in cervical cancer patients and a control population.

  19. Plant sex chromosome evolution.

    Science.gov (United States)

    Charlesworth, Deborah

    2013-01-01

    It is now well established that plants have an important place in studies of sex chromosome evolution because of the repeated independent evolution of separate sexes and sex chromosomes. There has been considerable recent progress in studying plant sex chromosomes. In this review, I focus on how these recent studies have helped clarify or answer several important questions about sex chromosome evolution, and I shall also try to clarify some common misconceptions. I also outline future work that will be needed to make further progress, including testing some important ideas by genetic, molecular, and developmental approaches. Systems with different ages can clearly help show the time course of events during changes from an ancestral co-sexual state (hermaphroditism or monoecy), and I will also explain how different questions can be studied in lineages whose dioecy or sex chromosomes evolved at different times in the past. PMID:23125359

  20. Vibrio chromosomes share common history

    OpenAIRE

    Gevers Dirk; Chang Sarah; Chang LeeAnn; Kirkup Benjamin C; Polz Martin F

    2010-01-01

    Abstract Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an open question to what extent the two chromosomes themselves share a common history since their formation. Results Single copy genes from each chromosome (142 genes from chromosome I and 42 genes from chromosome II) were identified from 19 sequenced Vibrionales genomes ...

  1. Genome-wide association analysis and replication of coronary artery disease in South Korea suggests a causal variant common to diverse populations

    Science.gov (United States)

    Cho, Eun Young; Jang, Yangsoo; Shin, Eun Soon; Jang, Hye Yoon; Yoo, Yeon-Kyeong; Kim, Sook; Jang, Ji Hyun; Lee, Ji Yeon; Yun, Min Hye; Park, Min Young; Chae, Jey Sook; Lim, Jin Woo; Shin, Dong Jik; Park, Sungha; Lee, Jong Ho; Han, Bok Ghee; Rae, Kim Hyung; Cardon, Lon R; Morris, Andrew P; Lee, Jong Eun; Clarke, Geraldine M

    2010-01-01

    Background Recent genome-wide association (GWA) studies have identified and replicated several genetic loci associated with the risk of development of coronary artery disease (CAD) in samples from populations of Caucasian and Asian descent. However, only chromosome 9p21 has been confirmed as a major susceptibility locus conferring risk for development of CAD across multiple ethnic groups. The authors aimed to find evidence of further similarities and differences in genetic risk of CAD between Korean and other populations. Methods The authors performed a GWA study comprising 230 cases and 290 controls from a Korean population typed on 490 032 single nucleotide polymorphisms (SNPs). A total of 3148 SNPs were taken forward for genotyping in a subsequent replication study using an independent sample of 1172 cases and 1087 controls from the same population. Results The association previously observed on chromosome 9p21 was independently replicated (p=3.08e–07). Within this region, the same risk haplotype was observed in samples from both Korea and of Western European descent, suggesting that the causal mutation carried on this background occurred on a single ancestral allele. Other than 9p21, the authors were unable to replicate any of the previously reported signals for association with CAD. Furthermore, no evidence of association was found at chromosome 1q41 for risk of myocardial infarction, previously identified as conferring risk in a Japanese population. Conclusion A common causal variant is likely to be responsible for risk of CAD in Korean and Western European populations at chromosome 9p21.3. Further investigations are required to confirm non-replication of any other cross-race genetic risk factors.

  2. Sequential cloning of chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Lacks, S.A.

    1991-12-31

    A method for sequential cloning of chromosomal DNA and chromosomal DNA cloned by this method are disclosed. The method includes the selection of a target organism having a segment of chromosomal DNA to be sequentially cloned. A first DNA segment, having a first restriction enzyme site on either side. homologous to the chromosomal DNA to be sequentially cloned is isolated. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes.

  3. Optimisation and validation of methods to assess single nucleotide polymorphisms (SNPs) in archival histological material

    International Nuclear Information System (INIS)

    Background and purpose: An increasing amount of evidence indicates that single nucleotide polymorphisms (SNPs) may affect a variety of oncology related phenotypes. Occasionally, it is convenient to base studies addressing genotype-phenotype relationships on historical patient cohorts, from which only archival specimens are available. This study was conducted to validate protocols optimised for assessment of SNPs based on paraffin embedded, formalin fixed tissue samples. Patients and methods: In 137 breast cancer patients, three TGFB1 SNPs were assessed based on archival histological specimens. In 37 of these patients, the SNPs were also assessed using cultured fibroblasts and the assays were validated by direct comparison of the results. From the remaining 100 patients, only archival material was available. In these patients, the existence of a genetic linkage pattern between the assessed TGFB1 SNPs was used to provide an indirect validation of the genotyping results. Furthermore, two different methods for DNA extraction were compared (semi-automatic DNA extraction using the ABI PrismTM 6100 Nucleic Acid PrepStation versus Proteinase K digestion for 5 days followed by boiling and DNA precipitation). Results: Assessment of SNPs based on archival histological material is encumbered by a number of obstacles and pitfalls. However, these can be widely overcome by careful optimisation of the methods used for sample selection, DNA extraction and PCR. Within 130 samples that fulfil the criteria for analysis a highly reliable SNP assessment was observed. The study demonstrated that different 'down-stream applications' ('single nucleotide primer extension' or 'TaqMan[reg]-based' real-time PCR) could be used as genotyping procedure. Conclusions: Reliable assessment of SNPs in formalin-fixed paraffin-embedded specimens is possible but a number of precautions should be carefully taken

  4. Identifying Prognostic SNPs in Clinical Cohorts: Complementing Univariate Analyses by Resampling and Multivariable Modeling

    Science.gov (United States)

    Hieke, Stefanie; Benner, Axel; Schlenk, Richard F.; Schumacher, Martin; Bullinger, Lars; Binder, Harald

    2016-01-01

    Clinical cohorts with time-to-event endpoints are increasingly characterized by measurements of a number of single nucleotide polymorphisms that is by a magnitude larger than the number of measurements typically considered at the gene level. At the same time, the size of clinical cohorts often is still limited, calling for novel analysis strategies for identifying potentially prognostic SNPs that can help to better characterize disease processes. We propose such a strategy, drawing on univariate testing ideas from epidemiological case-controls studies on the one hand, and multivariable regression techniques as developed for gene expression data on the other hand. In particular, we focus on stable selection of a small set of SNPs and corresponding genes for subsequent validation. For univariate analysis, a permutation-based approach is proposed to test at the gene level. We use regularized multivariable regression models for considering all SNPs simultaneously and selecting a small set of potentially important prognostic SNPs. Stability is judged according to resampling inclusion frequencies for both the univariate and the multivariable approach. The overall strategy is illustrated with data from a cohort of acute myeloid leukemia patients and explored in a simulation study. The multivariable approach is seen to automatically focus on a smaller set of SNPs compared to the univariate approach, roughly in line with blocks of correlated SNPs. This more targeted extraction of SNPs results in more stable selection at the SNP as well as at the gene level. Thus, the multivariable regression approach with resampling provides a perspective in the proposed analysis strategy for SNP data in clinical cohorts highlighting what can be added by regularized regression techniques compared to univariate analyses. PMID:27159447

  5. Identification and analysis of Single Nucleotide Polymorphisms (SNPs in the mosquito Anopheles funestus, malaria vector

    Directory of Open Access Journals (Sweden)

    Hemingway Janet

    2007-01-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs are the most common source of genetic variation in eukaryotic species and have become an important marker for genetic studies. The mosquito Anopheles funestus is one of the major malaria vectors in Africa and yet, prior to this study, no SNPs have been described for this species. Here we report a genome-wide set of SNP markers for use in genetic studies on this important human disease vector. Results DNA fragments from 50 genes were amplified and sequenced from 21 specimens of An. funestus. A third of specimens were field collected in Malawi, a third from a colony of Mozambican origin and a third form a colony of Angolan origin. A total of 494 SNPs including 303 within the coding regions of genes and 5 indels were identified. The physical positions of these SNPs in the genome are known. There were on average 7 SNPs per kilobase similar to that observed in An. gambiae and Drosophila melanogaster. Transitions outnumbered transversions, at a ratio of 2:1. The increased frequency of transition substitutions in coding regions is likely due to the structure of the genetic code and selective constraints. Synonymous sites within coding regions showed a higher polymorphism rate than non-coding introns or 3' and 5'flanking DNA with most of the substitutions in coding regions being observed at the 3rd codon position. A positive correlation in the level of polymorphism was observed between coding and non-coding regions within a gene. By genotyping a subset of 30 SNPs, we confirmed the validity of the SNPs identified during this study. Conclusion This set of SNP markers represents a useful tool for genetic studies in An. funestus, and will be useful in identifying candidate genes that affect diverse ranges of phenotypes that impact on vector control, such as resistance insecticide, mosquito behavior and vector competence.

  6. A new chromosome was born: comparative chromosome painting in Boechera.

    Science.gov (United States)

    Koch, Marcus A

    2015-09-01

    Comparative chromosome painting is a powerful tool to study the evolution of chromosomes and genomes. Analyzing karyotype evolution in cruciferous plants highlights the origin of aberrant chromosomes in apomictic Boechera and further establishes the cruciferous plants as important model system for our understanding of plant chromosome and genome evolution. PMID:26228436

  7. Chimpanzee chromosome 13 is homologous to human chromosome 2p

    Energy Technology Data Exchange (ETDEWEB)

    Sun, N. C.; Sun, C. R.Y.; Ho, T.

    1977-01-01

    Similarities between human and chimpanzee chromosomes are shown by chromosome banding techniques and somatic cell hybridization techniques. Cell hybrids were obtained from the chimpanzee lymphocyte LE-7, and the Chinese hamster mutant cell, Gal-2. Experiments showed that the ACPL, MDHs, and Gal-Act genes could be assigned to chimpanzee chromosome 13, and since these genes have been assigned to human chromosme 2p, it is suggested that chimpanzee chromosome 13 is homologous to human chromosome 2p. (HLW)

  8. Chromosome condensation and segmentation

    International Nuclear Information System (INIS)

    Some aspects of chromosome condensation in mammalians -humans especially- were studied by means of cytogenetic techniques of chromosome banding. Two further approaches were adopted: a study of normal condensation as early as prophase, and an analysis of chromosome segmentation induced by physical (temperature and γ-rays) or chemical agents (base analogues, antibiotics, ...) in order to show out the factors liable to affect condensation. Here 'segmentation' means an abnormal chromosome condensation appearing systematically and being reproducible. The study of normal condensation was made possible by the development of a technique based on cell synchronization by thymidine and giving prophasic and prometaphasic cells. Besides, the possibility of inducing R-banding segmentations on these cells by BrdU (5-bromodeoxyuridine) allowed a much finer analysis of karyotypes. Another technique was developed using 5-ACR (5-azacytidine), it allowed to induce a segmentation similar to the one obtained using BrdU and identify heterochromatic areas rich in G-C bases pairs

  9. Chromosomal abnormalities and autism

    Directory of Open Access Journals (Sweden)

    Farida El-Baz

    2016-01-01

    Conclusion: Chromosomal abnormalities were not detected in the studied autistic children, and so the relation between the genetics and autism still needs further work up with different study methods and techniques.

  10. Single Nucleotide Polymorphisms (SNPs) Discovery and Linkage Disequilibrium (LD) in Forest Trees

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    With completion of the Populus genome sequencing project and the availability of many expressed sequence tags (ESTs) databases in forest trees, attention is now rapidly shifting towards the study of individual genetic variation in natural populations. The most abundant form of genetic variation in many eukaryotic species is represented by single nucleotide polymorphisms (SNPs), which can account for heritable inter-individual differences in complex phenotypes. Unlike humans, the linkage disequilibrium (LD) rapidly decays within candidate genes in forest trees. Thus, SNPs-based candidate gene association studies are considered to be a most effective approach to dissect the complex quantitative traits in forest trees. The present study demonstrates that LD mapping can be used to identify alleles associated with quantitative traits and suggests that this new approach could be particularly useful for performing breeding programs in forest trees. In this review, we will describe the fundamentals, patterns of SNPs distribution and frequency, summarize recent advances in SNPs discovery and LD and comment on the application of LD in the dissection of complex quantitative traits in forest tress. We also put forward the outlook for future SNPs-based association analysis of quantitative traits in forest trees.

  11. Partition dataset according to amino acid type improves the prediction of deleterious non-synonymous SNPs

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jing; Li, Yuan-Yuan [School of Biotechnology, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Center for Bioinformation Technology, Shanghai 200235 (China); Li, Yi-Xue, E-mail: yxli@sibs.ac.cn [School of Biotechnology, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Center for Bioinformation Technology, Shanghai 200235 (China); Ye, Zhi-Qiang, E-mail: yezq@pkusz.edu.cn [Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055 (China); Key Laboratory of Systems Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China)

    2012-03-02

    Highlights: Black-Right-Pointing-Pointer Proper dataset partition can improve the prediction of deleterious nsSNPs. Black-Right-Pointing-Pointer Partition according to original residue type at nsSNP is a good criterion. Black-Right-Pointing-Pointer Similar strategy is supposed promising in other machine learning problems. -- Abstract: Many non-synonymous SNPs (nsSNPs) are associated with diseases, and numerous machine learning methods have been applied to train classifiers for sorting disease-associated nsSNPs from neutral ones. The continuously accumulated nsSNP data allows us to further explore better prediction approaches. In this work, we partitioned the training data into 20 subsets according to either original or substituted amino acid type at the nsSNP site. Using support vector machine (SVM), training classification models on each subset resulted in an overall accuracy of 76.3% or 74.9% depending on the two different partition criteria, while training on the whole dataset obtained an accuracy of only 72.6%. Moreover, the dataset was also randomly divided into 20 subsets, but the corresponding accuracy was only 73.2%. Our results demonstrated that partitioning the whole training dataset into subsets properly, i.e., according to the residue type at the nsSNP site, will improve the performance of the trained classifiers significantly, which should be valuable in developing better tools for predicting the disease-association of nsSNPs.

  12. Association of MHC region SNPs with irritant susceptibility in healthcare workers.

    Science.gov (United States)

    Yucesoy, Berran; Talzhanov, Yerkebulan; Michael Barmada, M; Johnson, Victor J; Kashon, Michael L; Baron, Elma; Wilson, Nevin W; Frye, Bonnie; Wang, Wei; Fluharty, Kara; Gharib, Rola; Meade, Jean; Germolec, Dori; Luster, Michael I; Nedorost, Susan

    2016-09-01

    Irritant contact dermatitis is the most common work-related skin disease, especially affecting workers in "wet-work" occupations. This study was conducted to investigate the association between single nucleotide polymorphisms (SNPs) within the major histocompatibility complex (MHC) and skin irritant response in a group of healthcare workers. 585 volunteer healthcare workers were genotyped for MHC SNPs and patch tested with three different irritants: sodium lauryl sulfate (SLS), sodium hydroxide (NaOH) and benzalkonium chloride (BKC). Genotyping was performed using Illumina Goldengate MHC panels. A number of SNPs within the MHC Class I (OR2B3, TRIM31, TRIM10, TRIM40 and IER3), Class II (HLA-DPA1, HLA-DPB1) and Class III (C2) genes were associated (p skin response to tested irritants in different genetic models. Linkage disequilibrium patterns and functional annotations identified two SNPs in the TRIM40 (rs1573298) and HLA-DPB1 (rs9277554) genes, with a potential impact on gene regulation. In addition, SNPs in PSMB9 (rs10046277 and ITPR3 (rs499384) were associated with hand dermatitis. The results are of interest as they demonstrate that genetic variations in inflammation-related genes within the MHC can influence chemical-induced skin irritation and may explain the connection between inflamed skin and propensity to subsequent allergic contact sensitization. PMID:27258892

  13. Association analysis identifies Melampsora ×columbiana poplar leaf rust resistance SNPs.

    Directory of Open Access Journals (Sweden)

    Jonathan La Mantia

    Full Text Available Populus species are currently being domesticated through intensive time- and resource-dependent programs for utilization in phytoremediation, wood and paper products, and conversion to biofuels. Poplar leaf rust disease can greatly reduce wood volume. Genetic resistance is effective in reducing economic losses but major resistance loci have been race-specific and can be readily defeated by the pathogen. Developing durable disease resistance requires the identification of non-race-specific loci. In the presented study, area under the disease progress curve was calculated from natural infection of Melampsora ×columbiana in three consecutive years. Association analysis was performed using 412 P. trichocarpa clones genotyped with 29,355 SNPs covering 3,543 genes. We found 40 SNPs within 26 unique genes significantly associated (permutated P<0.05 with poplar rust severity. Moreover, two SNPs were repeated in all three years suggesting non-race-specificity and three additional SNPs were differentially expressed in other poplar rust interactions. These five SNPs were found in genes that have orthologs in Arabidopsis with functionality in pathogen induced transcriptome reprogramming, Ca²⁺/calmodulin and salicylic acid signaling, and tolerance to reactive oxygen species. The additive effect of non-R gene functional variants may constitute high levels of durable poplar leaf rust resistance. Therefore, these findings are of significance for speeding the genetic improvement of this long-lived, economically important organism.

  14. Mining the 30UTR of Autism-implicated Genes for SNPs Perturbing MicroRNA Regulation

    Institute of Scientific and Technical Information of China (English)

    Varadharajan Vaishnavi; Mayakannan Manikandan; Arasambattu Kannan Munirajan

    2014-01-01

    Autism spectrum disorder (ASD) refers to a group of childhood neurodevelopmental dis-orders with polygenic etiology. The expression of many genes implicated in ASD is tightly regulated by various factors including microRNAs (miRNAs), a class of noncoding RNAs 22 nucleotides in length that function to suppress translation by pairing with‘miRNA recognition elements’ (MREs) present in the 30untranslated region (30UTR) of target mRNAs. This emphasizes the role played by miRNAs in regulating neurogenesis, brain development and differentiation and hence any perturba-tions in this regulatory mechanism might affect these processes as well. Recently, single nucleotide polymorphisms (SNPs) present within 30UTRs of mRNAs have been shown to modulate existing MREs or even create new MREs. Therefore, we hypothesized that SNPs perturbing miRNA-medi-ated gene regulation might lead to aberrant expression of autism-implicated genes, thus resulting in disease predisposition or pathogenesis in at least a subpopulation of ASD individuals. We developed a systematic computational pipeline that integrates data from well-established databases. By following a stringent selection criterion, we identified 9 MRE-modulating SNPs and another 12 MRE-creating SNPs in the 30UTR of autism-implicated genes. These high-confidence candidate SNPs may play roles in ASD and hence would be valuable for further functional validation.

  15. Enrichment of SNPs in Functional Categories Reveals Genes Affecting Complex Traits.

    Science.gov (United States)

    Zhao, Huiying; Fan, Dongsheng; Nyholt, Dale R; Yang, Yuedong

    2016-08-01

    Genome-wide association studies (GWAS) have indicated potential to identify heritability of common complex phenotypes, but traditional approaches have limited ability to detect hiding signals because single SNP has weak effect size accounting for only a small fraction of overall phenotypic variations. To improve the power of GWAS, methods have been developed to identify truly associated genes by jointly testing effects of all SNPs. However, equally considering all SNPs within a gene might dilute strong signals of SNPs in real functional categories. Here, we observed a consistent pattern on enrichment of significant SNPs in eight functional categories across six phenotypes, with the highest enrichment in coding and both UTR regions while the lowest enrichment in the intron. Based on the pattern of SNP enrichment in functional categories, we developed a new approach for detecting gene associations on traits (DGAT) by selecting the most significant functional category and then using SNPs within it to assess gene associations. The method was found to be robust in type I error rate on simulated data, and to have mostly higher power in detecting associated genes for three different diseases than other methods. Further analysis indicated ability of the DGAT to detect novel genes. The DGAT is available by http://sparks-lab.org/server/DGAT. PMID:27113629

  16. TRES: Identification of Discriminatory and Informative SNPs from Population Genomic Data.

    Science.gov (United States)

    Kavakiotis, Ioannis; Triantafyllidis, Alexandros; Ntelidou, Despoina; Alexandri, Panoraia; Megens, Hendrik-Jan; Crooijmans, Richard P M A; Groenen, Martien A M; Tsoumakas, Grigorios; Vlahavas, Ioannis

    2015-01-01

    The advent of high-throughput genomic technologies is enabling analyses on thousands or even millions of single-nucleotide polymorphisms (SNPs). At the same time, the selection of a minimum number of SNPs with the maximum information content is becoming increasingly problematic. Available locus ranking programs have been accused of providing upwardly biased results (concerning the predicted accuracy of the chosen set of markers for population assignment), cannot handle high-dimensional datasets, and some of them are computationally intensive. The toolbox for ranking and evaluation of SNPs (TRES) is a collection of algorithms built in a user-friendly and computationally efficient software that can manipulate and analyze datasets even in the order of millions of genotypes in a matter of seconds. It offers a variety of established methods for evaluating and ranking SNPs on user defined groups of populations and produces a set of predefined number of top ranked loci. Moreover, dataset manipulation algorithms enable users to convert datasets in different file formats, split the initial datasets into train and test sets, and finally create datasets containing only selected SNPs occurring from the SNP selection analysis for later on evaluation in dedicated software such as GENECLASS. This application can aid biologists to select loci with maximum power for optimization of cost-effective panels with applications related to e.g. species identification, wildlife management, and forensic problems. TRES is available for all operating systems at http://mlkd.csd.auth.gr/bio/tres. PMID:26137847

  17. A computational method for prediction of rSNPs in human genome.

    Science.gov (United States)

    Li, Rong; Han, Jiuqiang; Liu, Jun; Zheng, Jiguang; Liu, Ruiling

    2016-06-01

    Regulatory single nucleotide polymorphisms (rSNPs) in human genomes are thought to be responsible for phenotypic differences, including susceptibility to diseases and treatment outcomes, even they do not change any gene product. However, a genome-wide search for rSNPs has not been properly addressed so far. In this work, a computational method for rSNP identification is proposed. As background SNPs far outnumber rSNPs, an ensemble method is applied to handle imbalanced data, which firstly converts an unbalanced dataset into several balanced ones and then models for every balanced dataset. Two major types of features are extracted, that are sequence based features and allele-specific based features. Then random forest is applied to build the recognition model for each balanced dataset. Finally, ensemble strategies are adopted to combine the result of each model together. We have tested our method on a set of experimentally verified rSNPs, and leave-one-out cross-validation results showed that our method can achieve accuracy with sensitivity of 73.8%, specificity of 71.8% and the area under ROC curve (AUC) is 0.756. In addition, our method is threshold free and doesn't rely on data of regulatory elements, thus it will have better adaptability when facing different data scenarios. The original data and the source matlab codes involved are available at https://sourceforge.net/projects/rsnpdect/. PMID:27107687

  18. Partition dataset according to amino acid type improves the prediction of deleterious non-synonymous SNPs

    International Nuclear Information System (INIS)

    Highlights: ► Proper dataset partition can improve the prediction of deleterious nsSNPs. ► Partition according to original residue type at nsSNP is a good criterion. ► Similar strategy is supposed promising in other machine learning problems. -- Abstract: Many non-synonymous SNPs (nsSNPs) are associated with diseases, and numerous machine learning methods have been applied to train classifiers for sorting disease-associated nsSNPs from neutral ones. The continuously accumulated nsSNP data allows us to further explore better prediction approaches. In this work, we partitioned the training data into 20 subsets according to either original or substituted amino acid type at the nsSNP site. Using support vector machine (SVM), training classification models on each subset resulted in an overall accuracy of 76.3% or 74.9% depending on the two different partition criteria, while training on the whole dataset obtained an accuracy of only 72.6%. Moreover, the dataset was also randomly divided into 20 subsets, but the corresponding accuracy was only 73.2%. Our results demonstrated that partitioning the whole training dataset into subsets properly, i.e., according to the residue type at the nsSNP site, will improve the performance of the trained classifiers significantly, which should be valuable in developing better tools for predicting the disease-association of nsSNPs.

  19. Chromosome numbers in Bromeliaceae

    OpenAIRE

    2000-01-01

    The present study reports chromosome numbers of 17 species of Bromeliaceae, belonging to the genera Encholirium, Bromelia, Orthophytum, Hohenbergia, Billbergia, Neoglaziovia, Aechmea, Cryptanthus and Ananas. Most species present 2n = 50, however, Bromelia laciniosa, Orthophytum burle-marxii and O. maracasense are polyploids with 2n = 150, 2n = 100 and 2n = 150, respectively, while for Cryptanthus bahianus, 2n = 34 + 1-4B. B chromosomes were observed in Bromelia plumieri and Hohenbergia aff. u...

  20. All SNPs are not created equal: genome-wide association studies reveal a consistent pattern of enrichment among functionally annotated SNPs

    DEFF Research Database (Denmark)

    Schork, Andrew J; Thompson, Wesley K; Pham, Phillip;

    2013-01-01

    Recent results indicate that genome-wide association studies (GWAS) have the potential to explain much of the heritability of common complex phenotypes, but methods are lacking to reliably identify the remaining associated single nucleotide polymorphisms (SNPs). We applied stratified False...... Discovery Rate (sFDR) methods to leverage genic enrichment in GWAS summary statistics data to uncover new loci likely to replicate in independent samples. Specifically, we use linkage disequilibrium-weighted annotations for each SNP in combination with nominal p-values to estimate the True Discovery Rate...... (TDR = 1-FDR) for strata determined by different genic categories. We show a consistent pattern of enrichment of polygenic effects in specific annotation categories across diverse phenotypes, with the greatest enrichment for SNPs tagging regulatory and coding genic elements, little enrichment in...

  1. Seq4SNPs: new software for retrieval of multiple, accurately annotated DNA sequences, ready formatted for SNP assay design

    Science.gov (United States)

    Field, Helen I; Scollen, Serena A; Luccarini, Craig; Baynes, Caroline; Morrison, Jonathan; Dunning, Alison M; Easton, Douglas F; Pharoah, Paul DP

    2009-01-01

    Background In moderate-throughput SNP genotyping there was a gap in the workflow, between choosing a set of SNPs and submitting their sequences to proprietary assay design software, which was not met by existing software. Retrieval and formatting of sequences flanking each SNP, prior to assay design, becomes rate-limiting for more than about ten SNPs, especially if annotated for repetitive regions and adjacent variations. We routinely process up to 50 SNPs at once. Implementation We created Seq4SNPs, a web-based, walk-away software that can process one to several hundred SNPs given rs numbers as input. It outputs a file of fully annotated sequences formatted for one of three proprietary design softwares: TaqMan's Primer-By-Design FileBuilder, Sequenom's iPLEX or SNPstream's Autoprimer, as well as unannotated fasta sequences. We found genotyping assays to be inhibited by repetitive sequences or the presence of additional variations flanking the SNP under test, and in multiplexes, repetitive sequence flanking one SNP adversely affects multiple assays. Assay design software programs avoid such regions if the input sequences are appropriately annotated, so we used Seq4SNPs to provide suitably annotated input sequences, and improved our genotyping success rate. Adjacent SNPs can also be avoided, by annotating sequences used as input for primer design. Conclusion The accuracy of annotation by Seq4SNPs is significantly better than manual annotation (P < 1e-5). Using Seq4SNPs to incorporate all annotation for additional SNPs and repetitive elements into sequences, for genotyping assay designer software, minimizes assay failure at the design stage, reducing the cost of genotyping. Seq4SNPs provides a rapid route for replacement of poor test SNP sequences. We routinely use this software for assay sequence preparation. Seq4SNPs is available as a service at and , currently for human SNPs, but easily extended to include any species in dbSNP. PMID:19523221

  2. Micromechanics of human mitotic chromosomes

    International Nuclear Information System (INIS)

    Eukaryote cells dramatically reorganize their long chromosomal DNAs to facilitate their physical segregation during mitosis. The internal organization of folded mitotic chromosomes remains a basic mystery of cell biology; its understanding would likely shed light on how chromosomes are separated from one another as well as into chromosome structure between cell divisions. We report biophysical experiments on single mitotic chromosomes from human cells, where we combine micromanipulation, nano-Newton-scale force measurement and biochemical treatments to study chromosome connectivity and topology. Results are in accord with previous experiments on amphibian chromosomes and support the 'chromatin network' model of mitotic chromosome structure. Prospects for studies of chromosome-organizing proteins using siRNA expression knockdowns, as well as for differential studies of chromosomes with and without mutations associated with genetic diseases, are also discussed

  3. Vibrio chromosomes share common history

    Directory of Open Access Journals (Sweden)

    Gevers Dirk

    2010-05-01

    Full Text Available Abstract Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an open question to what extent the two chromosomes themselves share a common history since their formation. Results Single copy genes from each chromosome (142 genes from chromosome I and 42 genes from chromosome II were identified from 19 sequenced Vibrionales genomes and their phylogenetic comparison suggests consistent phylogenies for each chromosome. Additionally, study of the gene organization and phylogeny of the respective origins of replication confirmed the shared history. Conclusions Thus, while elements within the chromosomes may have experienced significant genetic mobility, the backbones share a common history. This allows conclusions based on multilocus sequence analysis (MLSA for one chromosome to be applied equally to both chromosomes.

  4. A robust linkage map of the porcine autosome based on gene-associated SNPs

    DEFF Research Database (Denmark)

    Vingborg, Rikke K K; Gregersen, Vivi R; Zhan, Bujie;

    2009-01-01

    Background Genetic linkage maps are necessary for mapping of mendelian traits and quantitative trait loci (QTLs). To identify the actual genes, which control these traits, a map based on gene-associated single nucleotide polymorphism (SNP) markers is highly valuable. In this study, the SNPs were...... genotyped in a large family material comprising more than 5,000 piglets derived from 12 Duroc boars crossed with 236 Danish Landrace/Danish Large White sows. The SNPs were identified in sequence alignments of 4,600 different amplicons obtained from the 12 boars and containing coding regions of genes derived...... from expressed sequence tags (ESTs) and genomic shotgun sequences. Results Linkage maps of all 18 porcine autosomes were constructed based on 456 gene-associated and six porcine EST-based SNPs. The total length of the averaged-sex whole porcine autosome was estimated to 1,711.8 cM resulting in an...

  5. Typing of 49 autosomal SNPs by single base extension and capillary electrophoresis for forensic genetic testing

    DEFF Research Database (Denmark)

    Børsting, Claus; Tomas Mas, Carmen; Morling, Niels

    2012-01-01

    We describe a method for simultaneous amplification of 49 autosomal single nucleotide polymorphisms (SNPs) by multiplex PCR and detection of the SNP alleles by single base extension (SBE) and capillary electrophoresis. All the SNPs may be amplified from only 100 pg of genomic DNA and the length of...... the amplicons range from 65 to 115 bp. The high sensitivity and the short amplicon sizes make the assay very suitable for typing of degraded DNA samples, and the low mutation rate of SNPs makes the assay very useful for relationship testing. Combined, these advantages make the assay well suited for...... disaster victim identifications, where the DNA from the victims may be highly degraded and the victims are identified via investigation of their relatives. The assay was validated according to the ISO 17025 standard and used for routine case work in our laboratory....

  6. Estimating the proportion of variation in susceptibility to multiple sclerosis captured by common SNPs

    Science.gov (United States)

    Watson, Corey T.; Disanto, Giulio; Breden, Felix; Giovannoni, Gavin; Ramagopalan, Sreeram V.

    2012-10-01

    Multiple sclerosis (MS) is a complex disease with underlying genetic and environmental factors. Although the contribution of alleles within the major histocompatibility complex (MHC) are known to exert strong effects on MS risk, much remains to be learned about the contributions of loci with more modest effects identified by genome-wide association studies (GWASs), as well as loci that remain undiscovered. We use a recently developed method to estimate the proportion of variance in disease liability explained by 475,806 single nucleotide polymorphisms (SNPs) genotyped in 1,854 MS cases and 5,164 controls. We reveal that ~30% of MS genetic liability is explained by SNPs in this dataset, the majority of which is accounted for by common variants. These results suggest that the unaccounted for proportion could be explained by variants that are in imperfect linkage disequilibrium with common GWAS SNPs, highlighting the potential importance of rare variants in the susceptibility to MS.

  7. Silver sulfide nanoparticles (Ag2S-NPs) are taken up by plants and are phytotoxic.

    Science.gov (United States)

    Wang, Peng; Menzies, Neal W; Lombi, Enzo; Sekine, Ryo; Blamey, F Pax C; Hernandez-Soriano, Maria C; Cheng, Miaomiao; Kappen, Peter; Peijnenburg, Willie J G M; Tang, Caixian; Kopittke, Peter M

    2015-01-01

    Silver nanoparticles (NPs) are used in more consumer products than any other nanomaterial and their release into the environment is unavoidable. Of primary concern is the wastewater stream in which most silver NPs are transformed to silver sulfide NPs (Ag2S-NPs) before being applied to agricultural soils within biosolids. While Ag2S-NPs are assumed to be biologically inert, nothing is known of their effects on terrestrial plants. The phytotoxicity of Ag and its accumulation was examined in short-term (24 h) and longer-term (2-week) solution culture experiments with cowpea (Vigna unguiculata L. Walp.) and wheat (Triticum aestivum L.) exposed to Ag2S-NPs (0-20 mg Ag L(-1)), metallic Ag-NPs (0-1.6 mg Ag L(-1)), or ionic Ag (AgNO3; 0-0.086 mg Ag L(-1)). Although not inducing any effects during 24-h exposure, Ag2S-NPs reduced growth by up to 52% over a 2-week period. This toxicity did not result from their dissolution and release of toxic Ag(+) in the rooting medium, with soluble Ag concentrations remaining below 0.001 mg Ag L(-1). Rather, Ag accumulated as Ag2S in the root and shoot tissues when plants were exposed to Ag2S-NPs, consistent with their direct uptake. Importantly, this differed from the form of Ag present in tissues of plants exposed to AgNO3. For the first time, our findings have shown that Ag2S-NPs exert toxic effects through their direct accumulation in terrestrial plant tissues. These findings need to be considered to ensure high yield of food crops, and to avoid increasing Ag in the food chain. PMID:25686712

  8. A Genome-Wide Investigation of SNPs and CNVs in Schizophrenia

    OpenAIRE

    Need, Anna C.; Ge, Dongliang; Weale, Michael E.; Maia, Jessica; Feng, Sheng; Heinzen, Erin L.; Shianna, Kevin V; Yoon, Woohyun; Kasperaviciute, Dalia; Gennarelli, Massimo; Strittmatter, Warren J.; Bonvicini, Cristian; Rossi, Giuseppe; Jayathilake, Karu; Cola, Philip A.

    2009-01-01

    We report a genome-wide assessment of single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) in schizophrenia. We investigated SNPs using 871 patients and 863 controls, following up the top hits in four independent cohorts comprising 1,460 patients and 12,995 controls, all of European origin. We found no genome-wide significant associations, nor could we provide support for any previously reported candidate gene or genome-wide associations. We went on to examine CNVs using a s...

  9. A genome-wide investigation of SNPs and CNVs in schizophrenia

    OpenAIRE

    Need, A.; Ge, D.; Weale, M; Maia, J.; Feng, S.; Heinzen, E; Shianna, K; Yoon, W.; Kasperavičiūtė, D.; M. GENNARELLI; Strittmatter, W; Bonvicini, C.; Rossi, G; Jayathilake, K.; De Cola, P.

    2009-01-01

    We report a genome-wide assessment of single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) in schizophrenia. We investigated SNPs using 871 patients and 863 controls, following up the top hits in four independent cohorts comprising 1,460 patients and 12,995 controls, all of European origin. We found no genome-wide significant associations, nor could we provide support for any previously reported candidate gene or genome-wide associations. We went on to examine CNVs using a s...

  10. Detection of cis-acting regulatory SNPs using allelic expression data

    OpenAIRE

    Xiao, Rui; Scott, Laura J.

    2011-01-01

    Allelic expression (AE) imbalance between the two alleles of a gene can be used to detect cis-acting regulatory SNPs (rSNPs) in individuals heterozygous for a transcribed SNP (tSNP). In this paper, we propose three tests for AE analysis focusing on phase-unknown data and any degree of linkage disequilibrium (LD) between the rSNP and tSNP: a test based on the minimum p-value of a one-sided F and two-sided t tests proposed previously for phase-unknown data, a test that combines these two p-valu...

  11. Typing of 49 autosomal SNPs by SNaPshot in the Slovenian population

    DEFF Research Database (Denmark)

    Drobnic, Katja; Børsting, Claus; Rockenbauer, Eszter;

    2010-01-01

    . Allele frequencies are presented for the 49 SNPs. No deviation from HWE was observed for any SNP. F(IS) and F(ST) were estimated. A principal coordinate analysis performed on six populations (Slovenian, Danish, Somali, Greenland, Turkish and Chinese) showed that the Slovenian population grouped with the......A total of 157 unrelated individuals residing in Slovenia were typed for 49 of the autosomal single nucleotide polymorphisms (SNPs) in the SNPforID 52plex with the SNaPshot assay. We obtained full SNP profiles in all but one individual and perfect concordance was obtained in duplicated analyses...

  12. Association between SNPs within candidate genes and compounds related to boar taint and reproduction

    DEFF Research Database (Denmark)

    Moe, Maren; Lien, Sigbjørn; Aasmundstad, Torunn;

    2009-01-01

    were genotyped in more than 2800 individuals and several SNPs were found to be significantly (LRT > 5.4) associated with the different phenotypes. Genes with significant SNPs in either of the traits investigated include cytochrome P450 members CYP2E1, CYP21, CYP2D6 and CYP2C49, steroid 5alpha...... in this study indicate that polymorphisms in CYP2E1, CYP21, CYP2D6, CYP2C49, NGFIB and CTNND1 might be used to reduce levels of boar taint without affecting levels of testosterone, estrone sulphate, 17beta-estradiol or length of bulbo urethralis gland. Udgivelsesdato: July...

  13. Typing of 24 mtDNA SNPs in a Chinese Population Using SNaPshot Minisequencing

    Institute of Scientific and Technical Information of China (English)

    黄代新; 桂程; 易少华; 杨庆恩; 杨荣芝; 梅焜

    2010-01-01

    Three SNaPshot multiplex assays were developed to test 23 coding region single nucleotide polymorphisms(SNPs) and one control region SNP outside hypervariable regions(HVR)Ⅰand Ⅱ,which was aimed at increasing the discrimination power of the mitochondrial DNA(mtDNA) typing in forensic casework,and confirming haplogroup assignments of mtDNA profiles in both human population studies and medical research.The selected SNPs targeted the East Asian phylogeny.These multiplex assays were validated by comparing with t...

  14. A genome-wide survey for SNPs altering microRNA seed sites identifies functional candidates in GWAS

    Directory of Open Access Journals (Sweden)

    Lee Yu-Chi

    2011-10-01

    Full Text Available Abstract Background Gene variants within regulatory regions are thought to be major contributors of the variation of complex traits/diseases. Genome wide association studies (GWAS, have identified scores of genetic variants that appear to contribute to human disease risk. However, most of these variants do not appear to be functional. Thus, the significance of the association may be brought up by still unknown mechanisms or by linkage disequilibrium (LD with functional polymorphisms. In the present study, focused on functional variants related with the binding of microRNAs (miR, we utilized SNP data, including newly released 1000 Genomes Project data to perform a genome-wide scan of SNPs that abrogate or create miR recognition element (MRE seed sites (MRESS. Results We identified 2723 SNPs disrupting, and 22295 SNPs creating MRESSs. We estimated the percent of SNPs falling within both validated (5% and predicted conserved MRESSs (3%. We determined 87 of these MRESS SNPs were listed in GWAS association studies, or in strong LD with a GWAS SNP, and may represent the functional variants of identified GWAS SNPs. Furthermore, 39 of these have evidence of co-expression of target mRNA and the predicted miR. We also gathered previously published eQTL data supporting a functional role for four of these SNPs shown to associate with disease phenotypes. Comparison of FST statistics (a measure of population subdivision for predicted MRESS SNPs against non MRESS SNPs revealed a significantly higher (P = 0.0004 degree of subdivision among MRESS SNPs, suggesting a role for these SNPs in environmentally driven selection. Conclusions We have demonstrated the potential of publicly available resources to identify high priority candidate SNPs for functional studies and for disease risk prediction.

  15. Chromosome numbers in Bromeliaceae

    Directory of Open Access Journals (Sweden)

    Cotias-de-Oliveira Ana Lúcia Pires

    2000-01-01

    Full Text Available The present study reports chromosome numbers of 17 species of Bromeliaceae, belonging to the genera Encholirium, Bromelia, Orthophytum, Hohenbergia, Billbergia, Neoglaziovia, Aechmea, Cryptanthus and Ananas. Most species present 2n = 50, however, Bromelia laciniosa, Orthophytum burle-marxii and O. maracasense are polyploids with 2n = 150, 2n = 100 and 2n = 150, respectively, while for Cryptanthus bahianus, 2n = 34 + 1-4B. B chromosomes were observed in Bromelia plumieri and Hohenbergia aff. utriculosa. The chromosome number of all species was determined for the first time, except for Billbergia chlorosticta and Cryptanthus bahianus. Our data supports the hypothesis of a basic number of x = 25 for the Bromeliaceae family and decreasing aneuploidy in the genus Cryptanthus.

  16. Those amazing dinoflagellate chromosomes

    Institute of Scientific and Technical Information of China (English)

    PETER J RIZZO

    2003-01-01

    Dinoflagellates are a very large and diverse group of eukaryotic algae that play a major role in aquatic food webs of both fresh water and marine habitats. Moreover, the toxic members of this group pose a health threat in the form of red tides. Finally, dinoflagellates are of great evolutionary importance,because of their taxonomic position, and their unusual chromosome structure and composition. While the cytoplasm of dinoflagellates is typically eukaryotic, the nucleus is unique when compared to the nucleus of other eukaryotes. More specifically, while the chromosomes of all other eukaryotes contain histones,dinoflagellate chromosomes lack histones completely. There are no known exceptions to this observation: all dinoflagellates lack histones, and all other eukaryotes contain histones. Nevertheless, dinoflagellates remain a relatively unstudied group of eukaryotes.

  17. SNPs for parentage testing and traceability in globally diverse breeds of sheep

    Science.gov (United States)

    DNA-based parentage determination accelerates genetic improvement by increasing pedigree accuracy. However, the utility of any “parentage SNP” varies by breed depending on its minor allele frequency (MAF) and its sequence context. Our aims were to identify parentage SNPs with exceptional qualities...

  18. Connecting SNPs in Diabetes: A Spatial Analysis of Meta-GWAS Loci

    Science.gov (United States)

    Schierding, William; O’Sullivan, Justin M.

    2015-01-01

    Meta-analyses of genome-wide association studies (GWAS) have improved our understanding of the genetic foundations of a number of diseases, including diabetes. However, single nucleotide polymorphisms (SNPs) that are identified by GWAS, especially those that fall outside of gene regions, do not always clearly link to the underlying biology. Despite this, these SNPs have often been validated through re-sequencing efforts as not just tag SNPs, but as causative SNPs, and so must play a role in disease development or progression. In this study, we show how the 3D genome (spatial connections) and trans-expression Quantitative Trait Loci connect diabetes loci from different GWAS meta-analyses, informing the backbone of regulatory networks. Our findings include a three-way functional–spatial connection between the TM6SF2, CTRB1–BCAR1, and CELSR2–PSRC1 loci (rs201189528, rs7202844, and rs7202844, respectively) connected through the KCNIP3 and BCAR1/BCAR3 loci, respectively. These spatial hubs serve as an example of how loci in genes with little biological connection to disease come together to contribute to the diabetes phenotype. PMID:26191039

  19. LD-Spline: Mapping SNPs on genotyping platforms to genomic regions using patterns of linkage disequilibrium

    Directory of Open Access Journals (Sweden)

    Bush William S

    2009-12-01

    Full Text Available Abstract Background Gene-centric analysis tools for genome-wide association study data are being developed both to annotate single locus statistics and to prioritize or group single nucleotide polymorphisms (SNPs prior to analysis. These approaches require knowledge about the relationships between SNPs on a genotyping platform and genes in the human genome. SNPs in the genome can represent broader genomic regions via linkage disequilibrium (LD, and population-specific patterns of LD can be exploited to generate a data-driven map of SNPs to genes. Methods In this study, we implemented LD-Spline, a database routine that defines the genomic boundaries a particular SNP represents using linkage disequilibrium statistics from the International HapMap Project. We compared the LD-Spline haplotype block partitioning approach to that of the four gamete rule and the Gabriel et al. approach using simulated data; in addition, we processed two commonly used genome-wide association study platforms. Results We illustrate that LD-Spline performs comparably to the four-gamete rule and the Gabriel et al. approach; however as a SNP-centric approach LD-Spline has the added benefit of systematically identifying a genomic boundary for each SNP, where the global block partitioning approaches may falter due to sampling variation in LD statistics. Conclusion LD-Spline is an integrated database routine that quickly and effectively defines the genomic region marked by a SNP using linkage disequilibrium, with a SNP-centric block definition algorithm.

  20. RNAsnp: efficient detection of local RNA secondary structure changes induced by SNPs

    DEFF Research Database (Denmark)

    Radhakrishnan, Sabarinathan; Tafer, Hakim; Seemann, Ernst Stefan; Hofacker, Ivo L.; Stadler, Peter F.; Gorodkin, Jan

    2013-01-01

    Structural characteristics are essential for the functioning of many noncoding RNAs and cis-regulatory elements of mRNAs. SNPs may disrupt these structures, interfere with their molecular function, and hence cause a phenotypic effect. RNA folding algorithms can provide detailed insights into stru...

  1. Biomarker Detection in Association Studies: Modeling SNPs Simultaneously via Logistic ANOVA

    KAUST Repository

    Jung, Yoonsuh

    2014-10-02

    In genome-wide association studies, the primary task is to detect biomarkers in the form of Single Nucleotide Polymorphisms (SNPs) that have nontrivial associations with a disease phenotype and some other important clinical/environmental factors. However, the extremely large number of SNPs comparing to the sample size inhibits application of classical methods such as the multiple logistic regression. Currently the most commonly used approach is still to analyze one SNP at a time. In this paper, we propose to consider the genotypes of the SNPs simultaneously via a logistic analysis of variance (ANOVA) model, which expresses the logit transformed mean of SNP genotypes as the summation of the SNP effects, effects of the disease phenotype and/or other clinical variables, and the interaction effects. We use a reduced-rank representation of the interaction-effect matrix for dimensionality reduction, and employ the L 1-penalty in a penalized likelihood framework to filter out the SNPs that have no associations. We develop a Majorization-Minimization algorithm for computational implementation. In addition, we propose a modified BIC criterion to select the penalty parameters and determine the rank number. The proposed method is applied to a Multiple Sclerosis data set and simulated data sets and shows promise in biomarker detection.

  2. Identification of pummelo cultivars by using a panel of 25 selected SNPs and 12 DNA segments.

    Directory of Open Access Journals (Sweden)

    Bo Wu

    Full Text Available Pummelo cultivars are usually difficult to identify morphologically, especially when fruits are unavailable. The problem was addressed in this study with the use of two methods: high resolution melting analysis of SNPs and sequencing of DNA segments. In the first method, a set of 25 SNPs with high polymorphic information content were selected from SNPs predicted by analyzing ESTs and sequenced DNA segments. High resolution melting analysis was then used to genotype 260 accessions including 55 from Myanmar, and 178 different genotypes were thus identified. A total of 99 cultivars were assigned to 86 different genotypes since the known somatic mutants were identical to their original genotypes at the analyzed SNP loci. The Myanmar samples were genotypically different from each other and from all other samples, indicating they were derived from sexual propagation. Statistical analysis showed that the set of SNPs was powerful enough for identifying at least 1000 pummelo genotypes, though the discrimination power varied in different pummelo groups and populations. In the second method, 12 genomic DNA segments of 24 representative pummelo accessions were sequenced. Analysis of the sequences revealed the existence of a high haplotype polymorphism in pummelo, and statistical analysis showed that the segments could be used as genetic barcodes that should be informative enough to allow reliable identification of 1200 pummelo cultivars. The high level of haplotype diversity and an apparent population structure shown by DNA segments and by SNP genotypes, respectively, were discussed in relation to the origin and domestication of the pummelo species.

  3. Chromosomal rearrangements in cattle and pigs revealed by chromosome microdissection and chromosome painting

    Directory of Open Access Journals (Sweden)

    Yerle Martine

    2003-11-01

    Full Text Available Abstract A pericentric inversion of chromosome 4 in a boar, as well as a case of (2q-;5p+ translocation mosaicism in a bull were analysed by chromosome painting using probes generated by conventional microdissection. For the porcine inversion, probes specific for p arms and q arms were produced and hybridised simultaneously on metaphases of a heterozygote carrier. In the case of the bovine translocation, two whole chromosome probes (chromosome 5, and derived chromosome 5 were elaborated and hybridised independently on chromosomal preparations of the bull who was a carrier of the mosaic translocation. The impossibility of differentiating chromosomes 2 and der(2 from other chromosomes of the metaphases did not allow the production of painting probes for these chromosomes. For all experiments, the quality of painting was comparable to that usually observed with probes obtained from flow-sorted chromosomes. The results obtained allowed confirmation of the interpretations proposed with G-banding karyotype analyses. In the bovine case, however, the reciprocity of the translocation could not be proven. The results presented in this paper show the usefulness of the microdissection technique for characterising chromosomal rearrangements in species for which commercial probes are not available. They also confirmed that the main limiting factor of the technique is the quality of the chromosomal preparations, which does not allow the identification of target chromosomes or chromosome fragments in all cases.

  4. Parent-of-origin effects in autism identified through genome-wide linkage analysis of 16,000 SNPs.

    Directory of Open Access Journals (Sweden)

    Delphine Fradin

    Full Text Available BACKGROUND: Autism is a common heritable neurodevelopmental disorder with complex etiology. Several genome-wide linkage and association scans have been carried out to identify regions harboring genes related to autism or autism spectrum disorders, with mixed results. Given the overlap in autism features with genetic abnormalities known to be associated with imprinting, one possible reason for lack of consistency would be the influence of parent-of-origin effects that may mask the ability to detect linkage and association. METHODS AND FINDINGS: We have performed a genome-wide linkage scan that accounts for potential parent-of-origin effects using 16,311 SNPs among families from the Autism Genetic Resource Exchange (AGRE and the National Institute of Mental Health (NIMH autism repository. We report parametric (GH, Genehunter and allele-sharing linkage (Aspex results using a broad spectrum disorder case definition. Paternal-origin genome-wide statistically significant linkage was observed on chromosomes 4 (LOD(GH = 3.79, empirical p<0.005 and LOD(Aspex = 2.96, p = 0.008, 15 (LOD(GH = 3.09, empirical p<0.005 and LOD(Aspex = 3.62, empirical p = 0.003 and 20 (LOD(GH = 3.36, empirical p<0.005 and LOD(Aspex = 3.38, empirical p = 0.006. CONCLUSIONS: These regions may harbor imprinted sites associated with the development of autism and offer fruitful domains for molecular investigation into the role of epigenetic mechanisms in autism.

  5. Association of p21 SNPs and risk of cervical cancer among Chinese women

    International Nuclear Information System (INIS)

    The p21 codon 31 single nucleotide polymorphism (SNP), rs1801270, has been linked to cervical cancer but with controversial results. The aims of this study were to investigate the role of p21 SNP-rs1801270 and other untested p21 SNPs in the risk of cervical cancer in a Chinese population. We genotyped five p21 SNPs (rs762623, rs2395655, rs1801270, rs3176352, and rs1059234) using peripheral blood DNA from 393 cervical cancer patients and 434 controls. The frequency of the rs1801270 A allele in patients (0.421) was significantly lower than that in controls (0.494, p = 0.003). The frequency of the rs3176352 C allele in cases (0.319) was significantly lower than that in controls (0.417, p < 0.001).The allele frequency of other three p21 SNPs showed not statistically significantly different between patients and controls. The rs1801270 AA genotype was associated with a decreased risk for the development of cervical cancer (OR = 0.583, 95%CI: 0.399 - 0.853, P = 0.005). We observed that the three p21 SNPs (rs1801270, rs3176352, and rs1059234) was in linkage disequilibrium (LD) and thus haplotype analysis was performed. The AGT haplotype (which includes the rs1801270A allele) was the most frequent haplotype among all subjects, and both homozygosity and heterozygosity for the AGT haplotype provided a protective effect from development of cervical cancer. We show an association between the p21 SNP rs1801270A allele and a decreased risk for cervical cancer in a population of Chinese women. The AGT haplotype formed by three p21 SNPs in LD (rs1801270, rs3176352 and rs1059234) also provided a protective effect in development of cervical cancer in this population

  6. PExFInS: An Integrative Post-GWAS Explorer for Functional Indels and SNPs.

    Science.gov (United States)

    Cheng, Zhongshan; Chu, Hin; Fan, Yanhui; Li, Cun; Song, You-Qiang; Zhou, Jie; Yuen, Kwok-Yung

    2015-01-01

    Expression quantitative trait loci (eQTLs) mapping and linkage disequilibrium (LD) analysis have been widely employed to interpret findings of genome-wide association studies (GWAS). With the availability of deep sequencing data of 423 lymphoblastoid cell lines (LCLs) from six global populations and the microarray expression data, we performed eQTL analysis, identified more than 228 K SNP cis-eQTLs and 21 K indel cis-eQTLs and generated a LCL cis-eQTL database. We demonstrate that the percentages of population-shared and population-specific cis-eQTLs are comparable; while indel cis-eQTLs in the population-specific subsection make more contribution to gene expression variations than those in the population-shared subsection. We found cis-eQTLs, especially the population-shared cis-eQTLs are significantly enriched toward transcription start site. Moreover, the National Human Genome Research Institute cataloged GWAS SNPs are enriched for LCL cis-eQTLs. Specifically, 32.8% GWAS SNPs are LCL cis-eQTLs, among which 12.5% can be tagged by indel cis-eQTLs, suggesting the fundamental contribution of indel cis-eQTLs to GWAS association signals. To search for functional indels and SNPs tagging GWAS SNPs, a pipeline Post-GWAS Explorer for Functional Indels and SNPs (PExFInS) has been developed, integrating LD analysis, functional annotation from public databases, cis-eQTL mapping with our LCL cis-eQTL database and other published cis-eQTL datasets. PMID:26612672

  7. Predicting deleterious nsSNPs: an analysis of sequence and structural attributes

    Directory of Open Access Journals (Sweden)

    Saqi Mansoor AS

    2006-04-01

    Full Text Available Abstract Background There has been an explosion in the number of single nucleotide polymorphisms (SNPs within public databases. In this study we focused on non-synonymous protein coding single nucleotide polymorphisms (nsSNPs, some associated with disease and others which are thought to be neutral. We describe the distribution of both types of nsSNPs using structural and sequence based features and assess the relative value of these attributes as predictors of function using machine learning methods. We also address the common problem of balance within machine learning methods and show the effect of imbalance on nsSNP function prediction. We show that nsSNP function prediction can be significantly improved by 100% undersampling of the majority class. The learnt rules were then applied to make predictions of function on all nsSNPs within Ensembl. Results The measure of prediction success is greatly affected by the level of imbalance in the training dataset. We found the balanced dataset that included all attributes produced the best prediction. The performance as measured by the Matthews correlation coefficient (MCC varied between 0.49 and 0.25 depending on the imbalance. As previously observed, the degree of sequence conservation at the nsSNP position is the single most useful attribute. In addition to conservation, structural predictions made using a balanced dataset can be of value. Conclusion The predictions for all nsSNPs within Ensembl, based on a balanced dataset using all attributes, are available as a DAS annotation. Instructions for adding the track to Ensembl are at http://www.brightstudy.ac.uk/das_help.html

  8. Identification of Type 2 Diabetes-associated combination of SNPs using Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Park Keun-Joon

    2010-04-01

    Full Text Available Abstract Background Type 2 diabetes mellitus (T2D, a metabolic disorder characterized by insulin resistance and relative insulin deficiency, is a complex disease of major public health importance. Its incidence is rapidly increasing in the developed countries. Complex diseases are caused by interactions between multiple genes and environmental factors. Most association studies aim to identify individual susceptibility single markers using a simple disease model. Recent studies are trying to estimate the effects of multiple genes and multi-locus in genome-wide association. However, estimating the effects of association is very difficult. We aim to assess the rules for classifying diseased and normal subjects by evaluating potential gene-gene interactions in the same or distinct biological pathways. Results We analyzed the importance of gene-gene interactions in T2D susceptibility by investigating 408 single nucleotide polymorphisms (SNPs in 87 genes involved in major T2D-related pathways in 462 T2D patients and 456 healthy controls from the Korean cohort studies. We evaluated the support vector machine (SVM method to differentiate between cases and controls using SNP information in a 10-fold cross-validation test. We achieved a 65.3% prediction rate with a combination of 14 SNPs in 12 genes by using the radial basis function (RBF-kernel SVM. Similarly, we investigated subpopulation data sets of men and women and identified different SNP combinations with the prediction rates of 70.9% and 70.6%, respectively. As the high-throughput technology for genome-wide SNPs improves, it is likely that a much higher prediction rate with biologically more interesting combination of SNPs can be acquired by using this method. Conclusions Support Vector Machine based feature selection method in this research found novel association between combinations of SNPs and T2D in a Korean population.

  9. Ring chromosome 13

    DEFF Research Database (Denmark)

    Brandt, C A; Hertz, Jens Michael; Petersen, M B; Vogel, F; Noer, H; Mikkelsen, M

    1992-01-01

    A stillborn male child with anencephaly and multiple malformations was found to have the karyotype 46,XY,r(13) (p11q21.1). The breakpoint at 13q21.1, determined by high resolution banding, is the most proximal breakpoint ever reported in patients with ring chromosome 13. In situ hybridisation with...

  10. The Y Chromosome

    Science.gov (United States)

    Offner, Susan

    2010-01-01

    The Y chromosome is of great interest to students and can be used to teach about many important biological concepts in addition to sex determination. This paper discusses mutation, recombination, mammalian sex determination, sex determination in general, and the evolution of sex determination in mammals. It includes a student activity that…

  11. Chromosomes, cancer and radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Samouhos, E.

    1983-08-01

    Some specific chromosomal abnormalities are associated with certain cancers. The earliest description of such a specific association is the one of the Philadelphia chromosome and myelogenous leukemia (1960). Other congenital karyotype abnormalities are associated with specific cancers. Examples of these are Down's syndrome with leukemia and Klinefelter's syndrome with male breast cancer. Genetic diseases of increased chromosome breakage, or of defective chromosome repair, are associated with greatly increased cancer incidence. Three such diseases have been recognized: 1) Fanconi's anemia, associated with leukemias and lymphomas, 2) Bloom's syndrome, associated with acute leukemias and lymphosarcoma, and 3) ataxia telangiectasia, associated with Hodgkin's disease, leukemia, and lymphosarcomas. Ten percent of individuals with ataxia telangiectasia will develop one of these neoplasms. Individuals with certain of these syndromes display an unusually high radiosensitivity. Radiation therapy for cancers has been fatal in patients who received as low as 3000 rad. This remarkable radiosensitivity has been quantitated in cell cultures from such cases. Evidence suggests that the apparent sensitivity may reflect subnormal ability to repair radiation damage. The rapid proliferation of information in this field stems from the interdigitation of many disciplines and specialties, including cytogenetics, cell biology, molecular biology, epidemiology, radiobiology, and several others. This paper is intended for clinicians; it presents a structured analytic scheme for correlating and classifying this multidisciplinary information as it becomes available.

  12. Chromosomes, cancer and radiosensitivity

    International Nuclear Information System (INIS)

    Some specific chromosomal abnormalities are associated with certain cancers. The earliest description of such a specific association is the one of the Philadelphia chromosome and myelogenous leukemia (1960). Other congenital karyotype abnormalities are associated with specific cancers. Examples of these are Down's syndrome with leukemia and Klinefelter's syndrome with male breast cancer. Genetic diseases of increased chromosome breakage, or of defective chromosome repair, are associated with greatly increased cancer incidence. Three such diseases have been recognized: 1) Fanconi's anemia, associated with leukemias and lymphomas, 2) Bloom's syndrome, associated with acute leukemias and lymphosarcoma, and 3) ataxia telangiectasia, associated with Hodgkin's disease, leukemia, and lymphosarcomas. Ten percent of individuals with ataxia telangiectasia will develop one of these neoplasms. Individuals with certain of these syndromes display an unusually high radiosensitivity. Radiation therapy for cancers has been fatal in patients who received as low as 3000 rad. This remarkable radiosensitivity has been quantitated in cell cultures from such cases. Evidence suggests that the apparent sensitivity may reflect subnormal ability to repair radiation damage. The rapid proliferation of information in this field stems from the interdigitation of many disciplines and specialties, including cytogenetics, cell biology, molecular biology, epidemiology, radiobiology, and several others. This paper is intended for clinicians; it presents a structured analytic scheme for correlating and classifying this multidisciplinary information as it becomes available

  13. Chromosome Morphology in Kniphofia.

    Directory of Open Access Journals (Sweden)

    J. M. J de Wet

    1960-12-01

    Full Text Available A number of species and varieties of the genus  Kniphofia (Liliaceae were studied cytologically. The somatic chromosome number is  2n = 12 in all the species. This is also true in  Notosceptrum natalense Baker.

  14. Telomere dysfunction and chromosome instability

    Energy Technology Data Exchange (ETDEWEB)

    Murnane, John P., E-mail: jmurnane@radonc.ucsf.edu [Department of Radiation Oncology, University of California San Francisco, 2340 Sutter Street, San Francisco, CA 94143-1331 (United States)

    2012-02-01

    The ends of chromosomes are composed of a short repeat sequence and associated proteins that together form a cap, called a telomere, that keeps the ends from appearing as double-strand breaks (DSBs) and prevents chromosome fusion. The loss of telomeric repeat sequences or deficiencies in telomeric proteins can result in chromosome fusion and lead to chromosome instability. The similarity between chromosome rearrangements resulting from telomere loss and those found in cancer cells implicates telomere loss as an important mechanism for the chromosome instability contributing to human cancer. Telomere loss in cancer cells can occur through gradual shortening due to insufficient telomerase, the protein that maintains telomeres. However, cancer cells often have a high rate of spontaneous telomere loss despite the expression of telomerase, which has been proposed to result from a combination of oncogene-mediated replication stress and a deficiency in DSB repair in telomeric regions. Chromosome fusion in mammalian cells primarily involves nonhomologous end joining (NHEJ), which is the major form of DSB repair. Chromosome fusion initiates chromosome instability involving breakage-fusion-bridge (B/F/B) cycles, in which dicentric chromosomes form bridges and break as the cell attempts to divide, repeating the process in subsequent cell cycles. Fusion between sister chromatids results in large inverted repeats on the end of the chromosome, which amplify further following additional B/F/B cycles. B/F/B cycles continue until the chromosome acquires a new telomere, most often by translocation of the end of another chromosome. The instability is not confined to a chromosome that loses its telomere, because the instability is transferred to the chromosome donating a translocation. Moreover, the amplified regions are unstable and form extrachromosomal DNA that can reintegrate at new locations. Knowledge concerning the factors promoting telomere loss and its consequences is

  15. Organization of the bacterial chromosome.

    OpenAIRE

    Krawiec, S.; Riley, M

    1990-01-01

    Recent progress in studies on the bacterial chromosome is summarized. Although the greatest amount of information comes from studies on Escherichia coli, reports on studies of many other bacteria are also included. A compilation of the sizes of chromosomal DNAs as determined by pulsed-field electrophoresis is given, as well as a discussion of factors that affect gene dosage, including redundancy of chromosomes on the one hand and inactivation of chromosomes on the other hand. The distinction ...

  16. Finding the founder of Stockholm - A kinship study based on Y-chromosomal, autosomal and mitochondrial DNA

    DEFF Research Database (Denmark)

    Malmström, Helena; Vretemark, Maria; Tillmar, Andreas;

    2012-01-01

    -chromosomal and autosomal SNPs and compared the results with haplogroup frequencies of modern Swedes to investigate paternal relations. Possible maternal kinship was investigated by deep FLX-sequencing of overlapping mtDNA amplicons. The authenticity of the sequences was examined using data from independent...... extractions, massive clonal data, the c-statistics, and real-time quantitative data. We show that the males carry the same Y-chromosomal haplogroup and thus we cannot reject a father-son type of relation. Further, as shown by the mtDNA analyses, none of the individuals are maternally related. We conclude that...

  17. Combined Use of Molecular Markers and High-Resolution Melting (HRM) to Assess Chromosome Dosage in Potato Hybrids.

    Science.gov (United States)

    Villano, Clizia; Miraglia, Valeria; Iorizzo, Massimo; Aversano, Riccardo; Carputo, Domenico

    2016-03-01

    In plants, the most widely used cytological techniques to assess parental genome contributions are based on in situ hybridization (FISH and GISH), but they are time-consuming and need specific expertise and equipment. Recent advances in genomics and molecular biology have made PCR-based markers a straightforward, affordable technique for chromosome typing. Here, we describe the development of a molecular assay that uses single-copy conserved ortholog set II (COSII)-based single nucleotide polymorphisms (SNPs) and the high-resolution melting (HRM) technique to assess the chromosome dosage of interspecific hybrids between a Solanum phureja-S. tuberosum diploid (2n = 2x = 24) hybrid and its wild relative S. commersonii. Screening and analysis of 45 COSII marker sequences allowed S. commersonii-specific SNPs to be identified for all 12 chromosomes. Combining the HRM technique with the establishment of synthetic DNA hybrids, SNP markers were successfully used to predict the expected parental chromosome ratio of 5 interspecific triploid hybrids. These results demonstrate the ability of this strategy to distinguish diverged genomes from each other, and to estimate chromosome dosage. The method could potentially be applied to any species as a tool to assess paternal to maternal ratios in the framework of a breeding program or following transformation techniques. PMID:26663623

  18. Quick, “Imputation-free” meta-analysis with proxy-SNPs

    Directory of Open Access Journals (Sweden)

    Meesters Christian

    2012-09-01

    Full Text Available Abstract Background Meta-analysis (MA is widely used to pool genome-wide association studies (GWASes in order to a increase the power to detect strong or weak genotype effects or b as a result verification method. As a consequence of differing SNP panels among genotyping chips, imputation is the method of choice within GWAS consortia to avoid losing too many SNPs in a MA. YAMAS (Yet Another Meta Analysis Software, however, enables cross-GWAS conclusions prior to finished and polished imputation runs, which eventually are time-consuming. Results Here we present a fast method to avoid forfeiting SNPs present in only a subset of studies, without relying on imputation. This is accomplished by using reference linkage disequilibrium data from 1,000 Genomes/HapMap projects to find proxy-SNPs together with in-phase alleles for SNPs missing in at least one study. MA is conducted by combining association effect estimates of a SNP and those of its proxy-SNPs. Our algorithm is implemented in the MA software YAMAS. Association results from GWAS analysis applications can be used as input files for MA, tremendously speeding up MA compared to the conventional imputation approach. We show that our proxy algorithm is well-powered and yields valuable ad hoc results, possibly providing an incentive for follow-up studies. We propose our method as a quick screening step prior to imputation-based MA, as well as an additional main approach for studies without available reference data matching the ethnicities of study participants. As a proof of principle, we analyzed six dbGaP Type II Diabetes GWAS and found that the proxy algorithm clearly outperforms naïve MA on the p-value level: for 17 out of 23 we observe an improvement on the p-value level by a factor of more than two, and a maximum improvement by a factor of 2127. Conclusions YAMAS is an efficient and fast meta-analysis program which offers various methods, including conventional MA as well as inserting proxy-SNPs

  19. [Chromosomal organization of the genomes of small-chromosome plants].

    Science.gov (United States)

    Muravenko, O V; Zelenin, A V

    2009-11-01

    An effective approach to study the chromosome organization in genomes of plants with small chromosomes and/or with low-informative C-banding patterns was developed in the course of investigation of the karyotypes of cotton plant, camomile, flax, and pea. To increase the resolving power of chromosome analysis, methods were worked out for revealing early replication patterns on chromosomes and for artificial impairment of mitotic chromosome condensation with the use of a DNA intercalator, 9-aminoacridine (9-AMA). To estimate polymorphism of the patterns of C-banding of small chromosomes on preparations obtained with the use of 9-AMA, it is necessary to choose a length interval that must not exceed three average sizes of metaphase chromosomes without the intercalator. The use of 9-AMA increases the resolution of differential C- and OR-banding and the precision of physical chromosome mapping by the FISH method. Of particular importance in studying small chromosomes is optimization of the computer-aided methods used to obtain and process chromosome images. The complex approach developed for analysis of the chromosome organization in plant genomes was used to study the karyotypes of 24 species of the genus Linum L. It permitted their chromosomes to be identified for the first time, and, in addition, B chromosomes were discovered and studied in the karyotypes of the species of the section Syllinum. By similarity of the karyotypes, the studied flax species were distributed in eight groups in agreement with the clusterization of these species according to the results of RAPD analysis performed in parallel. Systematic positions and phylogenetic relationships of the studied flax species were verified. Out results can serve as an important argument in favour of the proposal to develop a special program for sequencing the genome of cultivated flax (L. usitatissimum L.), which is a major representative of small-chromosome species. PMID:20058798

  20. A follow-up study for left ventricular mass on chromosome 12p11 identifies potential candidate genes

    Directory of Open Access Journals (Sweden)

    Slifer Susan

    2011-07-01

    Full Text Available Abstract Background Left ventricular mass (LVM is an important risk factor for cardiovascular disease. Previously we found evidence for linkage to chromosome 12p11 in Dominican families, with a significant increase in a subset of families with high average waist circumference (WC. In the present study, we use association analysis to further study the genetic effect on LVM. Methods Association analysis with LVM was done in the one LOD critical region of the linkage peak in an independent sample of 897 Caribbean Hispanics. Genotype data were available on 7085 SNPs from 23 to 53 MB on chromosome 12p11. Adjustment was made for vascular risk factors and population substructure using an additive genetic model. Subset analysis by WC was performed to test for a difference in genetic effects between the high and low WC subsets. Results In the overall analysis, the most significant association was found to rs10743465, downstream of the SOX5 gene (p = 1.27E-05. Also, 19 additional SNPs had nominal p TMTC1. Twelve additional SNPs in or near 6 genes had p Conclusions The current study supports previously identified evidence by linkage for a genetic effect on LVM on chromosome 12p11 using association analysis in population-based Caribbean Hispanic cohort. SOX5 may play an important role in the regulation of LVM. An interaction of TMTC1 with abdominal obesity may contribute to phenotypic variation of LVM.

  1. Non-invasive prenatal aneuploidy testing at chromosomes 13, 18, 21, X, and Y, using targeted sequencing of polymorphic loci

    Science.gov (United States)

    Zimmermann, Bernhard; Hill, Matthew; Gemelos, George; Demko, Zachary; Banjevic, Milena; Baner, Johan; Ryan, Allison; Sigurjonsson, Styrmir; Chopra, Nikhil; Dodd, Michael; Levy, Brynn; Rabinowitz, Matthew

    2012-01-01

    Objective Develop a non-invasive prenatal test based on analysis of cell-free DNA in maternal blood to detect fetal aneuploidy at chromosomes 13, 18, 21, X, and Y. Methods 166 samples from pregnant women, including eleven trisomy 21, three trisomy 18, two trisomy 13, two 45,X, and two 47,XXY samples were analyzed using an informatics-based method. Cell-free DNA from maternal blood was isolated and amplified using a multiplex PCR assay targeting 11,000 SNPs on chromosomes 13, 18, 21, X, and Y in a single reaction, then sequenced. A Bayesian-based Maximum Likelihood statistical method was applied to determine the chromosomal count of the five chromosomes interrogated in each sample, along with a sample-specific calculated accuracy for each test result. Results The algorithm correctly reported the chromosome copy number at all five chromosomes in 145 samples that passed a DNA quality test, for a total of 725/725 correct calls. The average calculated accuracy for these samples was 99.92%. Twenty-one samples did not pass the DNA quality test. Conclusions This informatics-based method non-invasively detected fetuses with trisomy 13, 18, and 21, 45,X, and 47,XXY with high sample-specific calculated accuracies for each individual chromosome and across all five chromosomes. PMID:23108718

  2. Analysis of 49 autosomal SNPs in three ethnic groups from Iran

    DEFF Research Database (Denmark)

    Sharafi Farzad, M; Tomas Mas, Carmen; Børsting, C;

    2013-01-01

    A total number of 149 individuals from Iran (Persians, Lurs and Kurds) were analyzed for 49 autosomal SNPs using PCR, SBE and capillary electrophoresis. No deviation from Hardy-Weinberg expectations was observed. One SNP pair (rs1015250-rs251934) showed significant linkage disequilibrium in Kurds....... However, this was most likely due to chance. High intrapopulation variability and no significant population structure were observed among the three ethnic groups from Iran. Pairwise FST values obtained from the mean numbers of pairwise differences between SNP profiles were calculated for Persians, Lurs...... Asian populations in the MDS plot drawn from the FST values. Statistical parameters of forensic interest calculated for the Iranian ethnic groups showed values of the same order of magnitudes as those obtained for Asians. The mean match probability calculated for the 49 SNPs ranged from 1.7x10(-18) for...

  3. Identification of SNPs associated with susceptibility for development of adverse reactions to radiotherapy.

    Science.gov (United States)

    Rosenstein, Barry S

    2011-02-01

    Although cancer treatment with radiation can produce high cure rates, adverse effects often result from radiotherapy. These toxicities are manifested as damage to normal tissues and organs in the radiation field. In recognition of the substantial variation in the intrinsic response of individuals to radiation, an effort began approximately 10 years ago to discover the genetic markers, primarily SNPs, which are associated with susceptibility for the development of these adverse responses to radiation therapy. The goal of this research is to identify the SNPs that could serve as the basis of an assay to predict which cancer patients are most likely to develop complications resulting from radiotherapy. This would permit personalization and optimization of the treatment plan for each cancer patient. PMID:21332318

  4. Functional SNPs in the human ficolin (FCN) genes reveal distinct geographical patterns

    DEFF Research Database (Denmark)

    Hummelshøj, Tina; Munthe-Fog, Lea; Madsen, Hans O;

    2008-01-01

    (Argentina, n=50). We identified the most common FCN gene polymorphisms in five ethnic groups. Large ethnic differences were observed and the African populations contained several SNPs that were not observed in the other groups. Several variations, that will have major impact on the function of the ficolin...... proteins, were found. Three novel amino acid variations in Ficolin-1*Gly303Ser, Ficolin-2*Arg103Cys, and Ficolin-2*Thr137Met SNP were predicted by computational analyses to have a major functional physicochemical effect on their respective proteins. Additionally, a Gly43Asp in Ficolin-1 affects the Gly......-Xaa-Yaa repeats and a Trp279STOP introduces a stop codon, thereby destroying the fibrinogen-like domain of Ficolin-1. In contrast to FCN1 and FCN2, the number of SNPs in FCN3 was very low. In conclusion, large ethnic differences in the FCN genes that will affect the concentration, structure, and function of the...

  5. Chromosome 19 International Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Pericak-Vance, M.A. (Duke Univ., Durham, NC (United States). Medical Center); Ropers, H.H. (Univ. Hospital Nijmegen, (The Netherlands). Dept. of Human Genetics); Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))

    1993-01-04

    The Second International Workshop on Human Chromosome 19 was hosted on January 25 and 26, 1992, by the Department of Human Genetics, University Hospital Nijmegen, The Netherlands, at the 'Meerdal Conference Center'. The workshop was supported by a grant from the European Community obtained through HUGO, the Dutch Research Organization (NWO) and the Muscular Dystrophy Association (MDA). Travel support for American participants was provided by the Department of Energy. The goals of this workshop were to produce genetic, physical and integrated maps of chromosome 19, to identify inconsistencies and gaps, and to discuss and exchange resources and techniques available for the completion of these maps. The second day of the meeting was largely devoted to region or disease specific efforts. In particular, the meeting served as a platform for assessing and discussing the recent progress made into the molecular elucidation of myotonic dystrophy.

  6. EphB2 SNPs and sporadic prostate cancer risk in African American men.

    Directory of Open Access Journals (Sweden)

    Christiane M Robbins

    Full Text Available The EphB2 gene has been implicated as a tumor suppressor gene somatically altered in both prostate cancer (PC and colorectal cancer. We have previously shown an association between an EphB2 germline nonsense variant and risk of familial prostate cancer among African American Men (AAM. Here we set out to test the hypothesis that common variation within the EphB2 locus is associated with increased risk of sporadic PC in AAM. We genotyped a set of 341 single nucleotide polymorphisms (SNPs encompassing the EphB2 locus, including known and novel coding and noncoding variants, in 490 AA sporadic PC cases and 567 matched controls. Single marker-based logistical regression analyses revealed seven EphB2 SNPs showing statistically significant association with prostate cancer risk in our population. The most significant association was achieved for a novel synonymous coding SNP, TGen-624, (Odds Ratio (OR  = 0.22; 95% Confidence Interval (CI 0.08-0.66, p = 1×10(-5. Two other SNPs also show significant associations toward a protective effect rs10465543 and rs12090415 (p = 1×10(-4, OR = 0.49 and 0.7, respectively. Two additional SNPs revealed trends towards an increase in risk of prostate cancer, rs4612601 and rs4263970 (p = 0.001, OR = 1.35 and 1.31, respectively. Furthermore, haplotype analysis revealed low levels of linkage disequilibrium within the region, with two blocks being associated with prostate cancer risk among our population. These data suggest that genetic variation at the EphB2 locus may increase risk of sporadic PC among AAM.

  7. SNPs selection using support vector regression and genetic algorithms in GWAS

    Science.gov (United States)

    2014-01-01

    Introduction This paper proposes a new methodology to simultaneously select the most relevant SNPs markers for the characterization of any measurable phenotype described by a continuous variable using Support Vector Regression with Pearson Universal kernel as fitness function of a binary genetic algorithm. The proposed methodology is multi-attribute towards considering several markers simultaneously to explain the phenotype and is based jointly on statistical tools, machine learning and computational intelligence. Results The suggested method has shown potential in the simulated database 1, with additive effects only, and real database. In this simulated database, with a total of 1,000 markers, and 7 with major effect on the phenotype and the other 993 SNPs representing the noise, the method identified 21 markers. Of this total, 5 are relevant SNPs between the 7 but 16 are false positives. In real database, initially with 50,752 SNPs, we have reduced to 3,073 markers, increasing the accuracy of the model. In the simulated database 2, with additive effects and interactions (epistasis), the proposed method matched to the methodology most commonly used in GWAS. Conclusions The method suggested in this paper demonstrates the effectiveness in explaining the real phenotype (PTA for milk), because with the application of the wrapper based on genetic algorithm and Support Vector Regression with Pearson Universal, many redundant markers were eliminated, increasing the prediction and accuracy of the model on the real database without quality control filters. The PUK demonstrated that it can replicate the performance of linear and RBF kernels. PMID:25573332

  8. Joint Modeling of Linkage and Association: Identifying SNPs Responsible for a Linkage Signal

    OpenAIRE

    Li, Mingyao; Boehnke, Michael; Abecasis, Gonçalo R

    2005-01-01

    Once genetic linkage has been identified for a complex disease, the next step is often association analysis, in which single-nucleotide polymorphisms (SNPs) within the linkage region are genotyped and tested for association with the disease. If a SNP shows evidence of association, it is useful to know whether the linkage result can be explained, in part or in full, by the candidate SNP. We propose a novel approach that quantifies the degree of linkage disequilibrium (LD) between the candidate...

  9. SparSNP: Fast and memory-efficient analysis of all SNPs for phenotype prediction

    OpenAIRE

    Abraham Gad; Kowalczyk Adam; Zobel Justin; Inouye Michael

    2012-01-01

    Abstract Background A central goal of genomics is to predict phenotypic variation from genetic variation. Fitting predictive models to genome-wide and whole genome single nucleotide polymorphism (SNP) profiles allows us to estimate the predictive power of the SNPs and potentially develop diagnostic models for disease. However, many current datasets cannot be analysed with standard tools due to their large size. Results We introduce SparSNP, a tool for fitting lasso linear models for massive S...

  10. Genome-wide association studies using haplotypes and individual SNPs in Simmental cattle.

    Directory of Open Access Journals (Sweden)

    Yang Wu

    Full Text Available Recent advances in high-throughput genotyping technologies have provided the opportunity to map genes using associations between complex traits and markers. Genome-wide association studies (GWAS based on either a single marker or haplotype have identified genetic variants and underlying genetic mechanisms of quantitative traits. Prompted by the achievements of studies examining economic traits in cattle and to verify the consistency of these two methods using real data, the current study was conducted to construct the haplotype structure in the bovine genome and to detect relevant genes genuinely affecting a carcass trait and a meat quality trait. Using the Illumina BovineHD BeadChip, 942 young bulls with genotyping data were introduced as a reference population to identify the genes in the beef cattle genome significantly associated with foreshank weight and triglyceride levels. In total, 92,553 haplotype blocks were detected in the genome. The regions of high linkage disequilibrium extended up to approximately 200 kb, and the size of haplotype blocks ranged from 22 bp to 199,266 bp. Additionally, the individual SNP analysis and the haplotype-based analysis detected similar regions and common SNPs for these two representative traits. A total of 12 and 7 SNPs in the bovine genome were significantly associated with foreshank weight and triglyceride levels, respectively. By comparison, 4 and 5 haplotype blocks containing the majority of significant SNPs were strongly associated with foreshank weight and triglyceride levels, respectively. In addition, 36 SNPs with high linkage disequilibrium were detected in the GNAQ gene, a potential hotspot that may play a crucial role for regulating carcass trait components.

  11. Genome-wide association studies using haplotypes and individual SNPs in Simmental cattle.

    Science.gov (United States)

    Wu, Yang; Fan, Huizhong; Wang, Yanhui; Zhang, Lupei; Gao, Xue; Chen, Yan; Li, Junya; Ren, HongYan; Gao, Huijiang

    2014-01-01

    Recent advances in high-throughput genotyping technologies have provided the opportunity to map genes using associations between complex traits and markers. Genome-wide association studies (GWAS) based on either a single marker or haplotype have identified genetic variants and underlying genetic mechanisms of quantitative traits. Prompted by the achievements of studies examining economic traits in cattle and to verify the consistency of these two methods using real data, the current study was conducted to construct the haplotype structure in the bovine genome and to detect relevant genes genuinely affecting a carcass trait and a meat quality trait. Using the Illumina BovineHD BeadChip, 942 young bulls with genotyping data were introduced as a reference population to identify the genes in the beef cattle genome significantly associated with foreshank weight and triglyceride levels. In total, 92,553 haplotype blocks were detected in the genome. The regions of high linkage disequilibrium extended up to approximately 200 kb, and the size of haplotype blocks ranged from 22 bp to 199,266 bp. Additionally, the individual SNP analysis and the haplotype-based analysis detected similar regions and common SNPs for these two representative traits. A total of 12 and 7 SNPs in the bovine genome were significantly associated with foreshank weight and triglyceride levels, respectively. By comparison, 4 and 5 haplotype blocks containing the majority of significant SNPs were strongly associated with foreshank weight and triglyceride levels, respectively. In addition, 36 SNPs with high linkage disequilibrium were detected in the GNAQ gene, a potential hotspot that may play a crucial role for regulating carcass trait components. PMID:25330174

  12. Identification of SNPs associated with susceptibility for development of adverse reactions to radiotherapy

    OpenAIRE

    Rosenstein, Barry S.

    2011-01-01

    Although cancer treatment with radiation can produce high cure rates, adverse effects often result from radiotherapy. These toxicities are manifested as damage to normal tissues and organs in the radiation field. In recognition of the substantial variation in the intrinsic response of individuals to radiation, an effort began approximately 10 years ago to discover the genetic markers, primarily SNPs, which are associated with susceptibility for the development of these adverse responses to ra...

  13. SNPs in stress-responsive rice genes: validation, genotyping, functional relevance and population structure

    OpenAIRE

    Parida Swarup K; Mukerji Mitali; Singh Ashok K; Singh Nagendra K; Mohapatra Trilochan

    2012-01-01

    Abstract Background Single nucleotide polymorphism (SNP) validation and large-scale genotyping are required to maximize the use of DNA sequence variation and determine the functional relevance of candidate genes for complex stress tolerance traits through genetic association in rice. We used the bead array platform-based Illumina GoldenGate assay to validate and genotype SNPs in a select set of stress-responsive genes to understand their functional relevance and study the population structure...

  14. Chromosomal gains and genomic loss of p53 and p16 genes in Barrett's esophagus detected by fluorescence in situ hybridization of cytology specimens.

    Science.gov (United States)

    Fahmy, Mona; Skacel, Marek; Gramlich, Terry L; Brainard, Jennifer A; Rice, Thomas W; Goldblum, John R; Connor, Jason T; Casey, Graham; Legator, Mona S; Tubbs, Raymond R; Falk, Gary W

    2004-05-01

    Endoscopic brush cytology is a promising surveillance technique for Barrett's esophagus. Ancillary markers are sought to increase the sensitivity of cytology and allow identification of patients at increased risk for disease progression. To determine if there are specific genetic changes in Barrett's esophagus with associated high-grade dysplasia/intramucosal adenocarcinoma compared to those without dysplasia, we performed fluorescence in situ hybridization (FISH) on cytologic specimens using probes to chromosomes and genomic regions previously described as altered in this disease. We studied archival brush cytology slides from 40 Barrett's esophagus patients: 21 with biopsy-proven high-grade dysplasia/carcinoma and 19 with no dysplasia and a minimum 5 years of negative follow-up. Centromeric enumeration probes (CEP) for chromosomes 6, 7, 11, and 12, and locus-specific probes (LSI) for 9p21 (p16 gene), and 17p13.1 (p53 gene) loci along with their corresponding CEP (9 and 17, respectively) were used in this study. A positive FISH result was defined as the presence of cells with >2 CEP signals or with a loss of the LSI signals relative to their corresponding CEP. p53 locus loss and/or aneusomy of chromosomes 6, 7, 11, and 12 abnormalities could be detected by FISH in routinely processed endoscopic brush cytology specimens from 95% of biopsy-positive cases with a specificity of 100%. Interestingly, all five cases with cytologic changes classified as indefinite for dysplasia from patients with a positive biopsy showed changes by FISH. Loss of the p16 locus was seen commonly in patients both with and without dysplasia/carcinoma. Selected biomarkers from this study merit further investigation to determine their potential to detect genetic changes in patients with Barrett's esophagus prior to the development of high-grade dysplasia. PMID:15017433

  15. Pedigree with frontotemporal lobar degeneration – motor neuron disease and Tar DNA binding protein-43 positive neuropathology: genetic linkage to chromosome 9

    Directory of Open Access Journals (Sweden)

    Loy Clement T

    2008-08-01

    Full Text Available Abstract Background Frontotemporal lobar degeneration (FTLD represents a clinically, pathologically and genetically heterogenous neurodegenerative disorder, often complicated by neurological signs such as motor neuron-related limb weakness, spasticity and paralysis, parkinsonism and gait disturbances. Linkage to chromosome 9p had been reported for pedigrees with the neurodegenerative disorder, frontotemporal lobar degeneration (FTLD and motor neuron disease (MND. The objective in this study is to identify the genetic locus in a multi-generational Australian family with FTLD-MND. Methods Clinical review and standard neuropathological analysis of brain sections from affected pedigree members. Genome-wide scan using microsatellite markers and single nucleotide polymorphism fine mapping. Examination of candidate genes by direct DNA sequencing. Results Neuropathological examination revealed cytoplasmic deposition of the TDP-43 protein in three affected individuals. Moreover, we identify a family member with clinical Alzheimer's disease, and FTLD-Ubiquitin neuropathology. Genetic linkage and haplotype analyses, defined a critical region between markers D9S169 and D9S1845 on chromosome 9p21. Screening of all candidate genes within this region did not reveal any novel genetic alterations that co-segregate with disease haplotype, suggesting that one individual carrying a meiotic recombination may represent a phenocopy. Re-analysis of linkage data using the new affection status revealed a maximal two-point LOD score of 3.24 and a multipoint LOD score of 3.41 at marker D9S1817. This provides the highest reported LOD scores from a single FTLD-MND pedigree. Conclusion Our reported increase in the minimal disease region should inform other researchers that the chromosome 9 locus may be more telomeric than predicted by published recombination boundaries. Moreover, the existence of a family member with clinical Alzheimer's disease, and who shares the disease

  16. TGFβ1 SNPs and radio-induced toxicity in prostate cancer patients

    International Nuclear Information System (INIS)

    Background and purpose: We have performed a case-control study in 413 prostate cancer patients to test for association between TGFβ1 and the development of late normal-tissue toxicity among prostate cancer patients treated with three-dimensional conformational radiotherapy (3D-CRT) Materials and methods: Late gastrointestinal and genitourinary toxicities were assessed for at least two years after radiotherapy in 413 patients according to CTCAEvs3 scores. Codominant genotypic tests and haplotypic analyses were undertaken to evaluate the correlation between TGFβ1 SNPs rs1800469, rs1800470 and rs1800472 and radio-induced toxicity. Results: Neither the SNPs nor the haplotypes were found to be associated with the risk of late toxicity. Conclusions: We were able to exclude up to a 2-fold increase in the risk of developing late gastrointestinal and genitourinary radio-induced toxicity due to the TGFβ1 SNPs rs1800469 and rs1800470, as well as the two most frequent TGFβ1 haplotypes.

  17. Identification of candidate SNPs for drug induced toxicity from differentially expressed genes in associated tissues.

    Science.gov (United States)

    Hasmats, Johanna; Kupershmidt, Ilya; Rodríguez-Antona, Cristina; Su, Qiaojuan Jane; Khan, Muhammad Suleman; Jara, Carlos; Mielgo, Xabier; Lundeberg, Joakim; Green, Henrik

    2012-09-10

    The growing collection of publicly available high-throughput data provides an invaluable resource for generating preliminary in silico data in support of novel hypotheses. In this study we used a cross-dataset meta-analysis strategy to identify novel candidate genes and genetic variations relevant to paclitaxel/carboplatin-induced myelosuppression and neuropathy. We identified genes affected by drug exposure and present in tissues associated with toxicity. From ten top-ranked genes 42 non-synonymous single nucleotide polymorphisms (SNPs) were identified in silico and genotyped in 94 cancer patients treated with carboplatin/paclitaxel. We observed variations in 11 SNPs, of which seven were present in a sufficient frequency for statistical evaluation. Of these seven SNPs, three were present in ABCA1 and ATM, and showed significant or borderline significant association with either myelosuppression or neuropathy. The strikingly high number of associations between genotype and clinically observed toxicity provides support for our data-driven computations strategy to identify biomarkers for drug toxicity. PMID:22759513

  18. Genetic association of SNPs in the FTO gene and predisposition to obesity in Malaysian Malays

    Directory of Open Access Journals (Sweden)

    Y.D. Apalasamy

    2012-12-01

    Full Text Available The common variants in the fat mass- and obesity-associated (FTO gene have been previously found to be associated with obesity in various adult populations. The objective of the present study was to investigate whether the single nucleotide polymorphisms (SNPs and linkage disequilibrium (LD blocks in various regions of the FTO gene are associated with predisposition to obesity in Malaysian Malays. Thirty-one FTO SNPs were genotyped in 587 (158 obese and 429 non-obese Malaysian Malay subjects. Obesity traits and lipid profiles were measured and single-marker association testing, LD testing, and haplotype association analysis were performed. LD analysis of the FTO SNPs revealed the presence of 57 regions with complete LD (D’ = 1.0. In addition, we detected the association of rs17817288 with low-density lipoprotein cholesterol. The FTO gene may therefore be involved in lipid metabolism in Malaysian Malays. Two haplotype blocks were present in this region of the FTO gene, but no particular haplotype was found to be significantly associated with an increased risk of obesity in Malaysian Malays.

  19. Genetic association of SNPs in the FTO gene and predisposition to obesity in Malaysian Malays

    Energy Technology Data Exchange (ETDEWEB)

    Apalasamy, Y.D. [Pharmacogenomics Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur (Malaysia); Ming, M.F.; Rampal, S.; Bulgiba, A. [Julius Centre University of Malaya, Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur (Malaysia); Mohamed, Z. [Pharmacogenomics Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur (Malaysia)

    2012-08-24

    The common variants in the fat mass- and obesity-associated (FTO) gene have been previously found to be associated with obesity in various adult populations. The objective of the present study was to investigate whether the single nucleotide polymorphisms (SNPs) and linkage disequilibrium (LD) blocks in various regions of the FTO gene are associated with predisposition to obesity in Malaysian Malays. Thirty-one FTO SNPs were genotyped in 587 (158 obese and 429 non-obese) Malaysian Malay subjects. Obesity traits and lipid profiles were measured and single-marker association testing, LD testing, and haplotype association analysis were performed. LD analysis of the FTO SNPs revealed the presence of 57 regions with complete LD (D' = 1.0). In addition, we detected the association of rs17817288 with low-density lipoprotein cholesterol. The FTO gene may therefore be involved in lipid metabolism in Malaysian Malays. Two haplotype blocks were present in this region of the FTO gene, but no particular haplotype was found to be significantly associated with an increased risk of obesity in Malaysian Malays.

  20. Novel SNPs in the Ankyrin 1 gene and their association with beef quality traits.

    Science.gov (United States)

    Horodyska, J; Sweeney, T; Ryan, M; Hamill, R M

    2015-10-01

    Single nucleotide polymorphisms (SNPs) in the promoter region of bovine Ankyrin 1 (ANK1) have been associated with tenderness and intramuscular fat level in beef. The objectives of this study were to characterise novel DNA variants in the coding region of bovine ANK1 and test for association with beef quality traits. A 3kb region of ANK1 cDNA was amplified and sequenced in 32 Charolais cattle using five sets of overlapping primers. Eighteen SNPs were identified and a predicted exon was confirmed. An in silico translation indicated that SNP4 and SNP16 were non-conservative. Three SNPs were genotyped in 158 crossbred cattle (n=158) with associated meat quality data. SNP6 was associated with texture scores while SNP17 was associated with juiciness. Haplotype (cHAP) 1 was associated with lightness, redness, ultimate pH, as well as sarcomere length. Alleles of the ANK1 gene could be potential targets for gene-assisted selection to improve a range of meat quality traits in beef. PMID:26051041

  1. Genetic association of SNPs in the FTO gene and predisposition to obesity in Malaysian Malays

    International Nuclear Information System (INIS)

    The common variants in the fat mass- and obesity-associated (FTO) gene have been previously found to be associated with obesity in various adult populations. The objective of the present study was to investigate whether the single nucleotide polymorphisms (SNPs) and linkage disequilibrium (LD) blocks in various regions of the FTO gene are associated with predisposition to obesity in Malaysian Malays. Thirty-one FTO SNPs were genotyped in 587 (158 obese and 429 non-obese) Malaysian Malay subjects. Obesity traits and lipid profiles were measured and single-marker association testing, LD testing, and haplotype association analysis were performed. LD analysis of the FTO SNPs revealed the presence of 57 regions with complete LD (D' = 1.0). In addition, we detected the association of rs17817288 with low-density lipoprotein cholesterol. The FTO gene may therefore be involved in lipid metabolism in Malaysian Malays. Two haplotype blocks were present in this region of the FTO gene, but no particular haplotype was found to be significantly associated with an increased risk of obesity in Malaysian Malays

  2. Enrichment of risk SNPs in regulatory regions implicate diverse tissues in Parkinson’s disease etiology

    Science.gov (United States)

    Coetzee, Simon G.; Pierce, Steven; Brundin, Patrik; Brundin, Lena; Hazelett, Dennis J.; Coetzee, Gerhard A.

    2016-01-01

    Recent genome-wide association studies (GWAS) of Parkinson’s disease (PD) revealed at least 26 risk loci, with associated single nucleotide polymorphisms (SNPs) located in non-coding DNA having unknown functions in risk. In order to explore in which cell types these SNPs (and their correlated surrogates at r2 ≥ 0.8) could alter cellular function, we assessed their location overlap with histone modification regions that indicate transcription regulation in 77 diverse cell types. We found statistically significant enrichment of risk SNPs at 12 loci in active enhancers or promoters. We investigated 4 risk loci in depth that were most significantly enriched (−logeP > 14) and contained 8 putative enhancers in the different cell types. These enriched loci, along with eQTL associations, were unexpectedly present in non-neuronal cell types. These included lymphocytes, mesendoderm, liver- and fat-cells, indicating that cell types outside the brain are involved in the genetic predisposition to PD. Annotating regulatory risk regions within specific cell types may unravel new putative risk mechanisms and molecular pathways that contribute to PD development. PMID:27461410

  3. Concordant gene expression in leukemia cells and normal leukocytes is associated with germline cis-SNPs.

    Directory of Open Access Journals (Sweden)

    Deborah French

    Full Text Available The degree to which gene expression covaries between different primary tissues within an individual is not well defined. We hypothesized that expression that is concordant across tissues is more likely influenced by genetic variability than gene expression which is discordant between tissues. We quantified expression of 11,873 genes in paired samples of primary leukemia cells and normal leukocytes from 92 patients with acute lymphoblastic leukemia (ALL. Genetic variation at >500,000 single nucleotide polymorphisms (SNPs was also assessed. The expression of only 176/11,783 (1.5% genes was correlated (p<0.008, FDR = 25% in the two tissue types, but expression of a high proportion (20 of these 176 genes was significantly related to cis-SNP genotypes (adjusted p<0.05. In an independent set of 134 patients with ALL, 14 of these 20 genes were validated as having expression related to cis-SNPs, as were 9 of 20 genes in a second validation set of HapMap cell lines. Genes whose expression was concordant among tissue types were more likely to be associated with germline cis-SNPs than genes with discordant expression in these tissues; genes affected were involved in housekeeping functions (GSTM2, GAPDH and NCOR1 and purine metabolism.

  4. Schizophrenia susceptibility genes on chromosome 13q32

    Institute of Scientific and Technical Information of China (English)

    胡颖; 许琪; 鞠桂芝; 刘树铮; 史杰萍; 于雅琴; 尉军

    2004-01-01

    @@Schizophrenia is a complex mental disorder affecting approximately 1% of the general population worldwide.1 It has a high incidence in the general population, a poor prognosis and a poor outcome, in that it has become a major social problem. Family, twin, and adoption studies have clearly shown that a genetic component is quite likely to play an important role in determining susceptibility to schizophrenia. The genome-wide scan indicates that several chromosomal regions are linked to schizophrenia, some of which have been replicated independently including 6p21-24, 8p21-22, 13q14-33 and 22q11-12.2,3 This study was designed to detect two single nucleotide polymorphisms (SNPs) located in the 13q14-33 region, rs188608 at the STK24 locus and rs2892679 at the GPC6 locus, among Chinese population.

  5. A set of EST-SNPs for map saturation and cultivar identification in melon

    Directory of Open Access Journals (Sweden)

    Monforte Antonio J

    2009-07-01

    Full Text Available Abstract Background There are few genomic tools available in melon (Cucumis melo L., a member of the Cucurbitaceae, despite its importance as a crop. Among these tools, genetic maps have been constructed mainly using marker types such as simple sequence repeats (SSR, restriction fragment length polymorphisms (RFLP and amplified fragment length polymorphisms (AFLP in different mapping populations. There is a growing need for saturating the genetic map with single nucleotide polymorphisms (SNP, more amenable for high throughput analysis, especially if these markers are located in gene coding regions, to provide functional markers. Expressed sequence tags (ESTs from melon are available in public databases, and resequencing ESTs or validating SNPs detected in silico are excellent ways to discover SNPs. Results EST-based SNPs were discovered after resequencing ESTs between the parental lines of the PI 161375 (SC × 'Piel de sapo' (PS genetic map or using in silico SNP information from EST databases. In total 200 EST-based SNPs were mapped in the melon genetic map using a bin-mapping strategy, increasing the map density to 2.35 cM/marker. A subset of 45 SNPs was used to study variation in a panel of 48 melon accessions covering a wide range of the genetic diversity of the species. SNP analysis correctly reflected the genetic relationships compared with other marker systems, being able to distinguish all the accessions and cultivars. Conclusion This is the first example of a genetic map in a cucurbit species that includes a major set of SNP markers discovered using ESTs. The PI 161375 × 'Piel de sapo' melon genetic map has around 700 markers, of which more than 500 are gene-based markers (SNP, RFLP and SSR. This genetic map will be a central tool for the construction of the melon physical map, the step prior to sequencing the complete genome. Using the set of SNP markers, it was possible to define the genetic relationships within a collection of forty

  6. 118 SNPs of folate-related genes and risks of spina bifida and conotruncal heart defects

    Directory of Open Access Journals (Sweden)

    Shaw Gary M

    2009-06-01

    Full Text Available Abstract Background Folic acid taken in early pregnancy reduces risks for delivering offspring with several congenital anomalies. The mechanism by which folic acid reduces risk is unknown. Investigations into genetic variation that influences transport and metabolism of folate will help fill this data gap. We focused on 118 SNPs involved in folate transport and metabolism. Methods Using data from a California population-based registry, we investigated whether risks of spina bifida or conotruncal heart defects were influenced by 118 single nucleotide polymorphisms (SNPs associated with the complex folate pathway. This case-control study included 259 infants with spina bifida and a random sample of 359 nonmalformed control infants born during 1983–86 or 1994–95. It also included 214 infants with conotruncal heart defects born during 1983–86. Infant genotyping was performed blinded to case or control status using a designed SNPlex assay. We examined single SNP effects for each of the 118 SNPs, as well as haplotypes, for each of the two outcomes. Results Few odds ratios (ORs revealed sizable departures from 1.0. With respect to spina bifida, we observed ORs with 95% confidence intervals that did not include 1.0 for the following SNPs (heterozygous or homozygous relative to the reference genotype: BHMT (rs3733890 OR = 1.8 (1.1–3.1, CBS (rs2851391 OR = 2.0 (1.2–3.1; CBS (rs234713 OR = 2.9 (1.3–6.7; MTHFD1 (rs2236224 OR = 1.7 (1.1–2.7; MTHFD1 (hcv11462908 OR = 0.2 (0–0.9; MTHFD2 (rs702465 OR = 0.6 (0.4–0.9; MTHFD2 (rs7571842 OR = 0.6 (0.4–0.9; MTHFR (rs1801133 OR = 2.0 (1.2–3.1; MTRR (rs162036 OR = 3.0 (1.5–5.9; MTRR (rs10380 OR = 3.4 (1.6–7.1; MTRR (rs1801394 OR = 0.7 (0.5–0.9; MTRR (rs9332 OR = 2.7 (1.3–5.3; TYMS (rs2847149 OR = 2.2 (1.4–3.5; TYMS (rs1001761 OR = 2.4 (1.5–3.8; and TYMS (rs502396 OR = 2.1 (1.3–3.3. However, multiple SNPs observed for a given gene showed evidence of linkage disequilibrium indicating

  7. Variation in conserved non-coding sequences on chromosome 5q andsusceptibility to asthma and atopy

    Energy Technology Data Exchange (ETDEWEB)

    Donfack, Joseph; Schneider, Daniel H.; Tan, Zheng; Kurz,Thorsten; Dubchak, Inna; Frazer, Kelly A.; Ober, Carole

    2005-09-10

    Background: Evolutionarily conserved sequences likely havebiological function. Methods: To determine whether variation in conservedsequences in non-coding DNA contributes to risk for human disease, westudied six conserved non-coding elements in the Th2 cytokine cluster onhuman chromosome 5q31 in a large Hutterite pedigree and in samples ofoutbred European American and African American asthma cases and controls.Results: Among six conserved non-coding elements (>100 bp,>70percent identity; human-mouse comparison), we identified one singlenucleotide polymorphism (SNP) in each of two conserved elements and sixSNPs in the flanking regions of three conserved elements. We genotypedour samples for four of these SNPs and an additional three SNPs each inthe IL13 and IL4 genes. While there was only modest evidence forassociation with single SNPs in the Hutterite and European Americansamples (P<0.05), there were highly significant associations inEuropean Americans between asthma and haplotypes comprised of SNPs in theIL4 gene (P<0.001), including a SNP in a conserved non-codingelement. Furthermore, variation in the IL13 gene was strongly associatedwith total IgE (P = 0.00022) and allergic sensitization to mold allergens(P = 0.00076) in the Hutterites, and more modestly associated withsensitization to molds in the European Americans and African Americans (P<0.01). Conclusion: These results indicate that there is overalllittle variation in the conserved non-coding elements on 5q31, butvariation in IL4 and IL13, including possibly one SNP in a conservedelement, influence asthma and atopic phenotypes in diversepopulations.

  8. Molecular fundamentals of chromosomal mutagenesis

    International Nuclear Information System (INIS)

    Precise quantitative correlation between the yield of chromosome structure damages and the yield of DNA damages is shown when comparing data on molecular and cytogenetic investigations carried out in cultural Mammalia cells. As the chromosome structure damage is to be connected with the damage of its carcass structure, then it is natural that DNA damage in loop regions is not to affect considerably the structure, while DNA damage lying on the loop base and connected with the chromosome carcass is to play a determining role in chromosomal mutagenesis. This DNA constitutes 1-2% from the total quantity of nuclear DNA. If one accepts that damages of these regions of DNA are ''hot'' points of chromosomal mutagenesis, then it becomes clear why 1-2% of preparation damages in a cell are realized in chromosome structural damages

  9. Electochemical detection of chromosome translocation

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Dimaki, Maria; Silahtaroglu, Asli;

    2014-01-01

    Cytogenetics is a study of the cell structure with a main focus on chromosomes content and their structure. Chromosome abnormalities, such as translocations may cause various genetic disorders and heametological malignancies. Chromosome translocations are structural rearrangements of two...... hybridization approach developed for label-free detection of the chromosome translocations. For specific translocation detection it is necessary to determine that the two DNA sequences forming a derivative chromosome are connected, which is achieved by two subsequent hybridization steps. The electrochemical...... impedance spectroscopy was selected as the sensing method on a microfabricated chip with array of 12 electrode sets. Two independent chips (Chip1 and Chip2) were used for targeting the chromosomal fragments involved in the translocation. Each chip was differentially functionalized with DNA probes matching...

  10. A Comprehensive Survey of Single Nucleotide Polymorphisms (SNPs) across Mycobacterium bovis Strains and M. bovis BCG Vaccine Strains Refines the Genealogy and Defines a Minimal Set of SNPs That Separate Virulent M. bovis Strains and M. bovis BCG Strains▿ †

    OpenAIRE

    Garcia Pelayo, M. Carmen; Uplekar, Swapna; Keniry, Andrew; Mendoza Lopez, Pablo; Garnier, Thierry; Nunez Garcia, Javier; Boschiroli, Laura; Zhou, Xiangmei; Parkhill, Julian; Smith, Noel; Hewinson, R Glyn; Cole, Stewart T.; Gordon, Stephen V.

    2009-01-01

    To further unravel the mechanisms responsible for attenuation of the tuberculosis vaccine Mycobacterium bovis BCG, comparative genomics was used to identify single nucleotide polymorphisms (SNPs) that differed between sequenced strains of Mycobacterium bovis and M. bovis BCG. SNPs were assayed in M. bovis isolates from France and the United Kingdom and from different BCG vaccines in order to identify those that arose during the attenuation process which gave rise to BCG. Informative data sets...

  11. Intraspecific chromosome variability

    Directory of Open Access Journals (Sweden)

    N Dubinin

    2010-12-01

    Full Text Available (Editorial preface. The publication is presented in order to remind us of one of dramatic pages of the history of genetics. It re-opens for the contemporary reader a comprehensive work marking the priority change from plant cytogenetics to animal cytogenetics led by wide population studies which were conducted on Drosophila polytene chromosomes. The year of the publication (1937 became the point of irretrievable branching between the directions of Old World and New World genetics connected with the problems of chromosome variability and its significance for the evolution of the species. The famous book of T. Dobzhansky (1937 was published by Columbia University in the US under the title “Genetics and the origin of species”, and in the shadow of this American ‘skybuilding’ all other works grew dim. It is remarkable that both Dobzhansky and Dubinin come to similar conclusions about the role of chromosomes in speciation. This is not surprising given that they both might be considered as representatives of the Russian genetic school, by their birth and education. Interestingly, Dobzhansky had never referred to the full paper of Dubinin et al. (1937, though a previous short communication in Nature (1936 was included together with all former papers on the related subject. In full, the volume of the original publication printed in the Biological Journal in Moscow comprised 47 pages, in that number 41 pages of the Russian text accompanied by 16 Figs, a table and reference list, and, above all, 6 pages of the English summary. This final part in English is now reproduced in the authors’ version with the only addition being the reference list in the originally printed form.

  12. Design of a High Density SNP Genotyping Assay in the Pig Using SNPs Identified and Characterized by Next Generation Sequencing Technology

    Science.gov (United States)

    The dissection of complex traits of economic importance for the pig industry requires the availability of a significant number of genetic markers, such as SNPs. This study was conducted in order to discover thousands of porcine SNPs using next generation sequencing technologies and use those SNPs, a...

  13. Reference-assisted chromosome assembly

    OpenAIRE

    Kim, Jaebum; Larkin, Denis M; Cai, Qingle; Asan,; Zhang, Yongfen; Ge, Ri-Li; Auvil, Loretta; Capitanu, Boris; Zhang, Guojie; Lewin, Harris A.; Ma, Jian

    2013-01-01

    One of the most difficult problems in modern genomics is the assembly of full-length chromosomes using next generation sequencing (NGS) data. To address this problem, we developed “reference-assisted chromosome assembly” (RACA), an algorithm to reliably order and orient sequence scaffolds generated by NGS and assemblers into longer chromosomal fragments using comparative genome information and paired-end reads. Evaluation of results using simulated and real genome assemblies indicates that ou...

  14. Diagnostic SNPs for inferring population structure in American mink (Neovison vison) identified through RAD sequencing

    DEFF Research Database (Denmark)

    2015-01-01

    Data from: "Diagnostic SNPs for inferring population structure in American mink (Neovison vison) identified through RAD sequencing" in Genomic Resources Notes accepted 1 October 2014 to 30 November 2014....

  15. Determinants of the Usage of Splice-Associated cis-Motifs Predict the Distribution of Human Pathogenic SNPs

    Science.gov (United States)

    Wu, XianMing; Hurst, Laurence D.

    2016-01-01

    Where in genes do pathogenic mutations tend to occur and does this provide clues as to the possible underlying mechanisms by which single nucleotide polymorphisms (SNPs) cause disease? As splice-disrupting mutations tend to occur predominantly at exon ends, known also to be hot spots of cis-exonic splice control elements, we examine the relationship between the relative density of such exonic cis-motifs and pathogenic SNPs. In particular, we focus on the intragene distribution of exonic splicing enhancers (ESE) and the covariance between them and disease-associated SNPs. In addition to showing that disease-causing genes tend to be genes with a high intron density, consistent with missplicing, five factors established as trends in ESE usage, are considered: relative position in exons, relative position in genes, flanking intron size, splice sites usage, and phase. We find that more than 76% of pathogenic SNPs are within 3–69 bp of exon ends where ESEs generally reside, this being 13% more than expected. Overall from enrichment of pathogenic SNPs at exon ends, we estimate that approximately 20–45% of SNPs affect splicing. Importantly, we find that within genes pathogenic SNPs tend to occur in splicing-relevant regions with low ESE density: they are found to occur preferentially in the terminal half of genes, in exons flanked by short introns and at the ends of phase (0,0) exons with 3′ non-“AGgt” splice site. We suggest the concept of the “fragile” exon, one home to pathogenic SNPs owing to its vulnerability to splice disruption owing to low ESE density. PMID:26545919

  16. Elucidating the Chromosome 9 Association with AS; CARD9 is a Candidate Gene

    OpenAIRE

    Pointon, Jennifer J.; Harvey, David; Karaderi, Tugce; Appleton, Louise H; Farrar, Claire; Stone, Millicent A; Sturrock, Roger D.; Brown, Matthew A; Wordsworth, B Paul

    2010-01-01

    Ankylosing spondylitis (AS) is polygenic with contributions from the immunologically relevant genes HLA-B*27, ERAP1 and IL23R. A recent genome-wide association study (GWAS) identified associations (p~0.005) with the non-synonymous single nucleotide polymorphisms (nsSNPs), rs4077515 and rs3812571, in CARD9 and SNAPC4 on chromosome 9q that had previously been linked to AS. We replicated these associations in a study of 730 AS patients compared to 2879 historic disease controls, (rs4077515 p = 0...

  17. Chromosome Connections: Compelling Clues to Common Ancestry

    Science.gov (United States)

    Flammer, Larry

    2013-01-01

    Students compare banding patterns on hominid chromosomes and see striking evidence of their common ancestry. To test this, human chromosome no. 2 is matched with two shorter chimpanzee chromosomes, leading to the hypothesis that human chromosome 2 resulted from the fusion of the two shorter chromosomes. Students test that hypothesis by looking for…

  18. X-chromosome workshop.

    Science.gov (United States)

    Paterson, A D

    1998-01-01

    Researchers presented results of ongoing research to the X-chromosome workshop of the Fifth World Congress on Psychiatric Genetics, covering a wide range of disorders: X-linked infantile spasms; a complex phenotype associated with deletions of Xp11; male homosexuality; degree of handedness; bipolar affective disorder; schizophrenia; childhood onset psychosis; and autism. This report summarizes the presentations, as well as reviewing previous studies. The focus of this report is on linkage findings for schizophrenia and bipolar disorder from a number of groups. For schizophrenia, low positive lod scores were obtained for markers DXS991 and DXS993 from two studies, although the sharing of alleles was greatest from brother-brother pairs in one study, and sister-sister in the other. Data from the Irish schizophrenia study was also submitted, with no strong evidence for linkage on the X chromosome. For bipolar disease, following the report of a Finnish family linked to Xq24-q27, the Columbia group reported some positive results for this region from 57 families, however, another group found no evidence for linkage to this region. Of interest, is the clustering of low positive linkage results that point to regions for possible further study. PMID:9686435

  19. Chromosome analysis and sorting

    Czech Academy of Sciences Publication Activity Database

    Doležel, Jaroslav; Kubaláková, Marie; Suchánková, Pavla; Kovářová, Pavlína; Bartoš, Jan; Šimková, Hana

    Weinheim : Wiley-VCH, 2007 - (Doležel, J.; Greilhuber, J.; Suda, J.), s. 373-403 ISBN 978-3-527-31487-4 R&D Projects: GA ČR GA521/04/0607; GA ČR GP521/05/P257; GA ČR GD521/05/H013; GA MŠk(CZ) LC06004 Grant ostatní: Mendelova zemědělská a lesnická univerzita v Brně / Agronomická fakulta(CZ) ME 844 Institutional research plan: CEZ:AV0Z5038910 Source of funding: V - iné verejné zdroje ; V - iné verejné zdroje ; V - iné verejné zdroje ; V - iné verejné zdroje ; V - iné verejné zdroje Keywords : Plant flow cytometry * chromosome sorting * flow cytogenetics Subject RIV: EB - Genetics ; Molecular Biology http://books. google .com/books?id=3cwakORieqUC&pg=PA373&lpg=PA373&dq=Chromosome+analysis+and+sorting&source=web&ots=8IyvJlBQyq&sig=_NlXyQQgBCwpj1pTC9YITvvVZqU

  20. Simultaneous analysis of all SNPs in genome-wide and re-sequencing association studies.

    Directory of Open Access Journals (Sweden)

    Clive J Hoggart

    Full Text Available Testing one SNP at a time does not fully realise the potential of genome-wide association studies to identify multiple causal variants, which is a plausible scenario for many complex diseases. We show that simultaneous analysis of the entire set of SNPs from a genome-wide study to identify the subset that best predicts disease outcome is now feasible, thanks to developments in stochastic search methods. We used a Bayesian-inspired penalised maximum likelihood approach in which every SNP can be considered for additive, dominant, and recessive contributions to disease risk. Posterior mode estimates were obtained for regression coefficients that were each assigned a prior with a sharp mode at zero. A non-zero coefficient estimate was interpreted as corresponding to a significant SNP. We investigated two prior distributions and show that the normal-exponential-gamma prior leads to improved SNP selection in comparison with single-SNP tests. We also derived an explicit approximation for type-I error that avoids the need to use permutation procedures. As well as genome-wide analyses, our method is well-suited to fine mapping with very dense SNP sets obtained from re-sequencing and/or imputation. It can accommodate quantitative as well as case-control phenotypes, covariate adjustment, and can be extended to search for interactions. Here, we demonstrate the power and empirical type-I error of our approach using simulated case-control data sets of up to 500 K SNPs, a real genome-wide data set of 300 K SNPs, and a sequence-based dataset, each of which can be analysed in a few hours on a desktop workstation.

  1. EphB2 SNPs and Sporadic Prostate Cancer Risk in African American Men

    OpenAIRE

    Christiane M Robbins; Stanley Hooker; Kittles, Rick A.; John D. Carpten

    2011-01-01

    The EphB2 gene has been implicated as a tumor suppressor gene somatically altered in both prostate cancer (PC) and colorectal cancer. We have previously shown an association between an EphB2 germline nonsense variant and risk of familial prostate cancer among African American Men (AAM). Here we set out to test the hypothesis that common variation within the EphB2 locus is associated with increased risk of sporadic PC in AAM. We genotyped a set of 341 single nucleotide polymorphisms (SNPs) enc...

  2. Association of obesity risk SNPs in PCSK1 with insulin sensitivity and proinsulin conversion

    Directory of Open Access Journals (Sweden)

    Häring Hans-Ulrich

    2010-06-01

    Full Text Available Abstract Background Prohormone convertase 1 is involved in maturation of peptides. Rare mutations in gene PCSK1, encoding this enzyme, cause childhood obesity and abnormal glucose homeostasis with elevated proinsulin concentrations. Common single nucleotide polymorphisms (SNPs within this gene, rs6232 and rs6235, are associated with obesity. We studied whether these SNPs influence the prediabetic traits insulin resistance, β-cell dysfunction, or glucose intolerance. Methods We genotyped 1498 German subjects for SNPs rs6232 and rs6235 within PCSK1. The subjects were metabolically characterized by oral glucose tolerance test with glucose, insulin, proinsulin, and C-peptide measurements. A subgroup of 512 subjects underwent a hyperinsulinemic-euglycemic clamp. Results The minor allele frequencies were 25.8% for SNP rs6235 and 6.0% for rs6232. After adjustment for sex and age, we found no association of SNPs rs6235 and rs6232 with BMI or other weight-related traits (all p ≥ 0.07. Both minor alleles, adjusted for sex, age, BMI and insulin sensitivity were associated with elevated AUCproinsulin and AUCproinsulin/AUCinsulin (rs6235: padditive model ≤ 0.009, effect sizes 8/8%, rs6232: pdominant model ≤ 0.01, effect sizes 10/21%. Insulin secretion was not affected by the variants (different secretion parameters, all p ≥ 0.08. The minor allele of SNP rs6232 was additionally associated with 15% higher OGTT-derived and 19% higher clamp-derived insulin sensitivity (pdom ≤ 0.0047, 4.5% lower HOMAIR (pdom = 0.02 and 3.5% lower 120-min glucose (pdom = 0.0003 independently of BMI and proinsulin conversion. SNP rs6235 was not associated with parameters of glucose metabolism. Conclusions Like rare mutations in PCSK1, the more common variants tested determine glucose-stimulated proinsulin conversion, but not insulin secretion. In addition, rs6232, encoding the amino acid exchange N221D, influences insulin sensitivity and glucose homeostasis.

  3. Rapid multiplex high resolution melting method to analyze inflammatory related SNPs in preterm birth

    Directory of Open Access Journals (Sweden)

    Pereyra Silvana

    2012-01-01

    Full Text Available Abstract Background Complex traits like cancer, diabetes, obesity or schizophrenia arise from an intricate interaction between genetic and environmental factors. Complex disorders often cluster in families without a clear-cut pattern of inheritance. Genomic wide association studies focus on the detection of tens or hundreds individual markers contributing to complex diseases. In order to test if a subset of single nucleotide polymorphisms (SNPs from candidate genes are associated to a condition of interest in a particular individual or group of people, new techniques are needed. High-resolution melting (HRM analysis is a new method in which polymerase chain reaction (PCR and mutations scanning are carried out simultaneously in a closed tube, making the procedure fast, inexpensive and easy. Preterm birth (PTB is considered a complex disease, where genetic and environmental factors interact to carry out the delivery of a newborn before 37 weeks of gestation. It is accepted that inflammation plays an important role in pregnancy and PTB. Methods Here, we used real time-PCR followed by HRM analysis to simultaneously identify several gene variations involved in inflammatory pathways on preterm labor. SNPs from TLR4, IL6, IL1 beta and IL12RB genes were analyzed in a case-control study. The results were confirmed either by sequencing or by PCR followed by restriction fragment length polymorphism. Results We were able to simultaneously recognize the variations of four genes with similar accuracy than other methods. In order to obtain non-overlapping melting temperatures, the key step in this strategy was primer design. Genotypic frequencies found for each SNP are in concordance with those previously described in similar populations. None of the studied SNPs were associated with PTB. Conclusions Several gene variations related to the same inflammatory pathway were screened through a new flexible, fast and non expensive method with the purpose of analyzing

  4. Cohesin in determining chromosome architecture

    Energy Technology Data Exchange (ETDEWEB)

    Haering, Christian H., E-mail: christian.haering@embl.de [Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg (Germany); Jessberger, Rolf, E-mail: rolf.jessberger@tu-dresden.de [Institute of Physiological Chemistry, Dresden University of Technology, Dresden (Germany)

    2012-07-15

    Cells use ring-like structured protein complexes for various tasks in DNA dynamics. The tripartite cohesin ring is particularly suited to determine chromosome architecture, for it is large and dynamic, may acquire different forms, and is involved in several distinct nuclear processes. This review focuses on cohesin's role in structuring chromosomes during mitotic and meiotic cell divisions and during interphase.

  5. Causes of oncogenic chromosomal translocation

    OpenAIRE

    Aplan, Peter D.

    2005-01-01

    Non-random chromosomal translocations are frequently associated with a variety of cancers, especially hematologic malignancies and childhood sarcomas In addition to their diagnostic utility, chromosomal translocations are increasingly being used in the clinic to guide therapeutic decisions. However, the mechanisms which cause these translocations remain poorly understood. Illegit...

  6. Genetics Home Reference: ring chromosome 20 syndrome

    Science.gov (United States)

    ... 3 links) Encyclopedia: Chromosome Encyclopedia: Epilepsy Health Topic: Epilepsy Genetic and Rare Diseases Information Center (1 link) Ring chromosome 20 Additional NIH Resources (2 links) National Human Genome Research Institute: Chromosome Abnormalities National Institute of ...

  7. Genetics Home Reference: ring chromosome 14 syndrome

    Science.gov (United States)

    ... Encyclopedia: Chromosome Health Topic: Developmental Disabilities Health Topic: Epilepsy Genetic and Rare Diseases Information Center (1 link) Ring chromosome 14 Additional NIH Resources (2 links) National Human Genome Research Institute: Chromosome Abnormalities National Institute of ...

  8. Bacterial chromosome organization and segregation.

    Science.gov (United States)

    Badrinarayanan, Anjana; Le, Tung B K; Laub, Michael T

    2015-01-01

    If fully stretched out, a typical bacterial chromosome would be nearly 1 mm long, approximately 1,000 times the length of a cell. Not only must cells massively compact their genetic material, but they must also organize their DNA in a manner that is compatible with a range of cellular processes, including DNA replication, DNA repair, homologous recombination, and horizontal gene transfer. Recent work, driven in part by technological advances, has begun to reveal the general principles of chromosome organization in bacteria. Here, drawing on studies of many different organisms, we review the emerging picture of how bacterial chromosomes are structured at multiple length scales, highlighting the functions of various DNA-binding proteins and the impact of physical forces. Additionally, we discuss the spatial dynamics of chromosomes, particularly during their segregation to daughter cells. Although there has been tremendous progress, we also highlight gaps that remain in understanding chromosome organization and segregation. PMID:26566111

  9. LD2SNPing: linkage disequilibrium plotter and RFLP enzyme mining for tag SNPs

    Directory of Open Access Journals (Sweden)

    Cheng Yu-Huei

    2009-06-01

    Full Text Available Abstract Background Linkage disequilibrium (LD mapping is commonly used to evaluate markers for genome-wide association studies. Most types of LD software focus strictly on LD analysis and visualization, but lack supporting services for genotyping. Results We developed a freeware called LD2SNPing, which provides a complete package of mining tools for genotyping and LD analysis environments. The software provides SNP ID- and gene-centric online retrievals for SNP information and tag SNP selection from dbSNP/NCBI and HapMap, respectively. Restriction fragment length polymorphism (RFLP enzyme information for SNP genotype is available to all SNP IDs and tag SNPs. Single and multiple SNP inputs are possible in order to perform LD analysis by online retrieval from HapMap and NCBI. An LD statistics section provides D, D', r2, δQ, ρ, and the P values of the Hardy-Weinberg Equilibrium for each SNP marker, and Chi-square and likelihood-ratio tests for the pair-wise association of two SNPs in LD calculation. Finally, 2D and 3D plots, as well as plain-text output of the results, can be selected. Conclusion LD2SNPing thus provides a novel visualization environment for multiple SNP input, which facilitates SNP association studies. The software, user manual, and tutorial are freely available at http://bio.kuas.edu.tw/LD2NPing.

  10. Single nucleotide polymorphisms (SNPs are inherited from parents and they measure heritable events

    Directory of Open Access Journals (Sweden)

    Hemminki Kari

    2005-01-01

    Full Text Available Abstract Single nucleotide polymorphisms (SNPs are extensively used in case-control studies of practically all cancer types. They are used for the identification of inherited cancer susceptibility genes and those that may interact with environmental factors. However, being genetic markers, they are applicable only on heritable conditions, which is often a neglected fact. Based on the data in the nationwide Swedish Family-Cancer Database, we review familial risks for all main cancers and discuss the evidence for a heritable component in cancer. The available evidence is not conclusive but it is consistent in pointing to a minor heritable etiology in cancer, which will hamper the success of SNP-based association studies. Empirical familial risks should be used as guidance for the planning of SNP studies. We provide calculations for the assessment of familial risks for assumed allele frequencies and gene effects (odds ratios for different modes of inheritance. Based on these data, we discuss the gene effects that could account for the unexplained proportion of familial breast and lung cancer. As a conclusion, we are concerned about the indiscriminate use of a genetic tool to cancers, which are mainly environmental in origin. We consider the likelihood of a successful application of SNPs in gene-environment studies small, unless established environmental risk factors are tested on proven candidate genes.

  11. Optimization of heteroduplex analysis for the detection of BRCA mutations and SNPs

    Directory of Open Access Journals (Sweden)

    Lucian Negura

    2011-02-01

    Full Text Available BRCA1 and BRCA2 are tumour suppressor genes whose mutant phenotypes predispose to breast and ovarian cancer. Screening for mutations in these genes is now standard practice for hereditary breast and ovarian cancer (HBOC cases in Europe, and permits medical follow-up and genetic counselling adapted to the needs of individuals in such families. Currently, most laboratories performing diagnostic analysis of the BRCA genes use PCR of exons and intron-exon boundaries coupled to a pre-screening step to identify anomalous amplicons. The techniques employed for the detection of mutations and SNPs have evolved over time and vary in sensitivity, specificity and cost-effectiveness. As a variant for pre-screening techniques, we chose the recently developed Surveyor® heteroduplex cleavage method as a sensitive and specific technique to reveal anomalous amplicons of the BRCA genes, using only basic laboratory equipment and agarose gel electrophoresis. Here we present the detection of either mutations or SNPs within the BRCA1 exon 7, using heteroduplex analysis (HA by mismatch-specific endonuclease, confirmed by dideoxy sequencing.

  12. Analysis of Case-Control Association Studies: SNPs, Imputation and Haplotypes

    KAUST Repository

    Chatterjee, Nilanjan

    2009-11-01

    Although prospective logistic regression is the standard method of analysis for case-control data, it has been recently noted that in genetic epidemiologic studies one can use the "retrospective" likelihood to gain major power by incorporating various population genetics model assumptions such as Hardy-Weinberg-Equilibrium (HWE), gene-gene and gene-environment independence. In this article we review these modern methods and contrast them with the more classical approaches through two types of applications (i) association tests for typed and untyped single nucleotide polymorphisms (SNPs) and (ii) estimation of haplotype effects and haplotype-environment interactions in the presence of haplotype-phase ambiguity. We provide novel insights to existing methods by construction of various score-tests and pseudo-likelihoods. In addition, we describe a novel two-stage method for analysis of untyped SNPs that can use any flexible external algorithm for genotype imputation followed by a powerful association test based on the retrospective likelihood. We illustrate applications of the methods using simulated and real data. © Institute of Mathematical Statistics, 2009.

  13. Evaluation of random forest regression for prediction of breeding value from genomewide SNPs

    Indian Academy of Sciences (India)

    Rupam Kumar Sarkar; A. R. Rao; Prabina Kumar Meher; T. Nepolean; T. Mohapatra

    2015-06-01

    Genomic prediction is meant for estimating the breeding value using molecular marker data which has turned out to be a powerful tool for efficient utilization of germplasm resources and rapid improvement of cultivars. Model-based techniques have been widely used for prediction of breeding values of genotypes from genomewide association studies. However, application of the random forest (RF), a model-free ensemble learning method, is not widely used for prediction. In this study, the optimum values of tuning parameters of RF have been identified and applied to predict the breeding value of genotypes based on genomewide single-nucleotide polymorphisms (SNPs), where the number of SNPs ($P$ variables) is much higher than the number of genotypes ($n$ observations) ($P >> n$). Further, a comparison was made with the model-based genomic prediction methods, namely, least absolute shrinkage and selection operator (LASSO), ridge regression (RR) and elastic net (EN) under $P >> n$. It was found that the correlations between the predicted and observed trait response were 0.591, 0.539, 0.431 and 0.587 for RF, LASSO, RR and EN, respectively, which implies superiority of the RF over the model-based techniques in genomic prediction. Hence, we suggest that the RF methodology can be used as an alternative to the model-based techniques for the prediction of breeding value at genome level with higher accuracy.

  14. ADN et chromosomes

    OpenAIRE

    Hayes, Hélène

    2000-01-01

    Chaque chromosome contient une seule molécule d’ADN. L’ADN déroulé d’un noyau de cellule humaine mesurerait environ 1,8 m : chaque molécule d’ADN est enroulée et compactée en plusieurs étapes, grâce à l’association de différentes protéines, et loge dans le noyau de 6 µm de diamètre. Le degré de condensation de l’ADN est variable selon les régions chromosomiques et les régions les moins condensées sont les plus riches en gènes. L’ADN est composé d’une variété de séquences codantes ou non et ré...

  15. X-Chromosome dosage compensation.

    Science.gov (United States)

    Meyer, Barbara J

    2005-01-01

    In mammals, flies, and worms, sex is determined by distinctive regulatory mechanisms that cause males (XO or XY) and females (XX) to differ in their dose of X chromosomes. In each species, an essential X chromosome-wide process called dosage compensation ensures that somatic cells of either sex express equal levels of X-linked gene products. The strategies used to achieve dosage compensation are diverse, but in all cases, specialized complexes are targeted specifically to the X chromosome(s) of only one sex to regulate transcript levels. In C. elegans, this sex-specific targeting of the dosage compensation complex (DCC) is controlled by the same developmental signal that establishes sex, the ratio of X chromosomes to sets of autosomes (X:A signal). Molecular components of this chromosome counting process have been defined. Following a common step of regulation, sex determination and dosage compensation are controlled by distinct genetic pathways. C. elegans dosage compensation is implemented by a protein complex that binds both X chromosomes of hermaphrodites to reduce transcript levels by one-half. The dosage compensation complex resembles the conserved 13S condensin complex required for both mitotic and meiotic chromosome resolution and condensation, implying the recruitment of ancient proteins to the new task of regulating gene expression. Within each C. elegans somatic cell, one of the DCC components also participates in the separate mitotic/meiotic condensin complex. Other DCC components play pivotal roles in regulating the number and distribution of crossovers during meiosis. The strategy by which C. elegans X chromosomes attract the condensin-like DCC is known. Small, well-dispersed X-recognition elements act as entry sites to recruit the dosage compensation complex and to nucleate spreading of the complex to X regions that lack recruitment sites. In this manner, a repressed chromatin state is spread in cis over short or long distances, thus establishing the

  16. Association between SNPs in defined functional pathways and risk of early or late toxicity as well as individual radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Reuther, Sebastian; Raabe, Annette; Borgmann, Kerstin; Dikomey, Ekkehard [University Medical Center Hamburg-Eppendorf, Laboratory of Radiobiology and Experimental Radiooncology, Department of Radiotherapy and Radiooncology, Hamburg (Germany); Szymczak, Silke [University at Luebeck, Institute of Medical Biometry and Statistics, University Medical Center Schleswig-Holstein (Germany); Christian-Albrechts-University Kiel, Institute of Clinical Molecular Biology, Kiel (Germany); Ziegler, Andreas [University at Luebeck, Institute of Medical Biometry and Statistics, University Medical Center Schleswig-Holstein (Germany); University of Luebeck, Center for Clinical Trials, Luebeck (Germany); Petersen, Cordula [University Medical Center Hamburg-Eppendorf, Clinic of Radiotherapy and Radiooncology, Hamburg (Germany); Hoeller, Ulrike [Charite Universitaetsmedizin Berlin, Department of Radiotherapy, Berlin (Germany)

    2014-08-26

    The aim of this study was to determine the impact of functional single nucleotide polymorphism (SNP) pathways involved in the ROS pathway, DNA repair, or TGFB1 signaling on acute or late normal toxicity as well as individual radiosensitivity. Patients receiving breast-conserving surgery and radiotherapy were examined either for erythema (n = 83), fibrosis (n = 123), or individual radiosensitivity (n = 123). The 17 SNPs analyzed are involved in the ROS pathway (GSTP1, SOD2, NQO1, NOS3, XDH), DNA repair (XRCC1, XRCC3, XRCC6, ERCC2, LIG4, ATM) or TGFB signaling (SKIL, EP300, APC, AXIN1, TGFB1). Associations with biological and clinical endpoints were studied for single SNPs but especially for combinations of SNPs assuming that a SNP is either beneficial or deleterious and needs to be weighted. With one exception, no significant association was seen between a single SNP and the three endpoints studied. No significant associations were also observed when applying a multi-SNP model assuming that each SNP was deleterious. In contrast, significant associations were obtained when SNPs were suggested to be either beneficial or deleterious. These associations increased, when each SNP was weighted individually. Detailed analysis revealed that both erythema and individual radiosensitivity especially depend on SNPs affecting DNA repair and TGFB1 signaling, while SNPs in ROS pathway were of minor importance. Functional pathways of SNPs may be used to form a risk score allowing to predict acute and late radiation-induced toxicity but also to unravel the underlying biological mechanisms. (orig.) [German] Fuer ein SNP-Netzwerk (''single nucleotide polymorphism'', Einzelnukleotidpolymorphismus), welches im ROS-Signalweg, an der DNA-Reparatur und im TGFB1-Signalweg involviert ist, sollen die Bedeutung fuer die akute und spaete Toxizitaet sowie die individuelle Strahlenempfindlichkeit bestimmt werden. Nach Strahlentherapie wurden Brustkrebspatientinnen entweder

  17. Y-chromosome haplotype distribution in Han Chinese populations and modern human origin in East Asians

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We investigated the distribution of Y-chromosome haplotype using 19 Y-SNPs in Han Chinese populations from 22 provinces of China. Our data indicate distinctive patterns of Y chromosome between southern and northern Han Chinese populations. The southern populations are much more polymorphic than northern populations. The latter has only a subset of the southern haplotypes. This result confirms the genetic difference observed between southern and northern ethnic populations in East Asia. It supports the hypothesis that the first settlement of modern hu-mans of African origin occurred in the southern part of East Asia during the last Ice Age, and a northward migration led to the peopling of northern China.

  18. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the continued development of a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and...

  19. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and inversions) have profound genetic...

  20. Association between SNPs in defined functional pathways and risk of early or late toxicity as well as individual radiosensitivity

    International Nuclear Information System (INIS)

    The aim of this study was to determine the impact of functional single nucleotide polymorphism (SNP) pathways involved in the ROS pathway, DNA repair, or TGFB1 signaling on acute or late normal toxicity as well as individual radiosensitivity. Patients receiving breast-conserving surgery and radiotherapy were examined either for erythema (n = 83), fibrosis (n = 123), or individual radiosensitivity (n = 123). The 17 SNPs analyzed are involved in the ROS pathway (GSTP1, SOD2, NQO1, NOS3, XDH), DNA repair (XRCC1, XRCC3, XRCC6, ERCC2, LIG4, ATM) or TGFB signaling (SKIL, EP300, APC, AXIN1, TGFB1). Associations with biological and clinical endpoints were studied for single SNPs but especially for combinations of SNPs assuming that a SNP is either beneficial or deleterious and needs to be weighted. With one exception, no significant association was seen between a single SNP and the three endpoints studied. No significant associations were also observed when applying a multi-SNP model assuming that each SNP was deleterious. In contrast, significant associations were obtained when SNPs were suggested to be either beneficial or deleterious. These associations increased, when each SNP was weighted individually. Detailed analysis revealed that both erythema and individual radiosensitivity especially depend on SNPs affecting DNA repair and TGFB1 signaling, while SNPs in ROS pathway were of minor importance. Functional pathways of SNPs may be used to form a risk score allowing to predict acute and late radiation-induced toxicity but also to unravel the underlying biological mechanisms. (orig.)

  1. Natural Functional SNPs in miR-155 Alter Its Expression Level, Blood Cell Counts, and Immune Responses

    Science.gov (United States)

    Li, Congcong; He, Huabin; Liu, An; Liu, Huazhen; Huang, Haibo; Zhao, Changzhi; Jing, Lu; Ni, Juan; Yin, Lilin; Hu, Suqin; Wu, Hui; Li, Xinyun; Zhao, Shuhong

    2016-01-01

    miR-155 has been confirmed to be a key factor in immune responses in humans and other mammals. Therefore, investigation of variations in miR-155 could be useful for understanding the differences in immunity between individuals. In this study, four SNPs in miR-155 were identified in mice (Mus musculus) and humans (Homo sapiens). In mice, the four SNPs were closely linked and formed two miR-155 haplotypes (A and B). Ten distinct types of blood parameters were associated with miR-155 expression under normal conditions. Additionally, 4 and 14 blood parameters were significantly different between these two genotypes under normal and lipopolysaccharide (LPS) stimulation conditions, respectively. Moreover, the expression levels of miR-155, the inflammatory response to LPS stimulation, and the lethal ratio following Salmonella typhimurium infection were significantly increased in mice harboring the AA genotype. Further, two SNPs, one in the loop region and the other near the 3′ terminal of pre-miR-155, were confirmed to be responsible for the differential expression of miR-155 in mice. Interestingly, two additional SNPs, one in the loop region and the other in the middle of miR-155*, modulated the function of miR-155 in humans. Predictions of secondary RNA structure using RNAfold showed that these SNPs affected the structure of miR-155 in both mice and humans. Our results provide novel evidence of the natural functional SNPs of miR-155 in both mice and humans, which may affect the expression levels of mature miR-155 by modulating its secondary structure. The SNPs of human miR-155 may be considered as causal mutations for some immune-related diseases in the clinic. The two genotypes of mice could be used as natural models for studying the mechanisms of immune diseases caused by abnormal expression of miR-155 in humans. PMID:27532002

  2. Mitotic chromosome condensation in vertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Vagnarelli, Paola, E-mail: P.Vagnarelli@ed.ac.uk

    2012-07-15

    Work from several laboratories over the past 10-15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292-301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories-a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307-316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119-1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579-589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different classes

  3. Mitotic chromosome condensation in vertebrates

    International Nuclear Information System (INIS)

    Work from several laboratories over the past 10–15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292–301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories—a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307–316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119–1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579–589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different

  4. Generation of meiomaps of genome-wide recombination and chromosome segregation in human oocytes.

    Science.gov (United States)

    Ottolini, Christian S; Capalbo, Antonio; Newnham, Louise; Cimadomo, Danilo; Natesan, Senthilkumar A; Hoffmann, Eva R; Ubaldi, Filippo M; Rienzi, Laura; Handyside, Alan H

    2016-07-01

    We have developed a protocol for the generation of genome-wide maps (meiomaps) of recombination and chromosome segregation for the three products of human female meiosis: the first and second polar bodies (PB1 and PB2) and the corresponding oocyte. PB1 is biopsied and the oocyte is artificially activated by exposure to calcium ionophore, after which PB2 is biopsied and collected with the corresponding oocyte. The whole genomes of the polar bodies and oocytes are amplified by multiple displacement amplification and, together with maternal genomic DNA, genotyped for ∼300,000 single-nucleotide polymorphisms (SNPs) genome-wide by microarray. Informative maternal heterozygous SNPs are phased using a haploid PB2 or oocyte as a reference. A simple algorithm is then used to identify the maternal haplotypes for each chromosome, in all of the products of meiosis for each oocyte. This allows mapping of crossovers and analysis of chromosome segregation patterns. The protocol takes a minimum of 3-5 d and requires a clinical embryologist with micromanipulation experience and a molecular biologist with basic bioinformatic skills. It has several advantages over previous methods; importantly, the use of artificial oocyte activation avoids the creation of embryos for research purposes. In addition, compared with next-generation sequencing, targeted SNP genotyping is cost-effective and it simplifies the bioinformatic analysis, as only one haploid reference sample is required to establish phase for maternal haplotyping. Finally, meiomapping is more informative than copy-number analysis alone for analysis of chromosome segregation patterns. Using this protocol, we have provided new insights that may lead to improvements in assisted reproduction for the treatment of infertility. PMID:27310263

  5. Genome-wide association study identifies a region on chromosome 11q14.3 associated with late rectal bleeding following radiation therapy for prostate cancer*

    Science.gov (United States)

    Kerns, Sarah L.; Stock, Richard; Stone, Nelson N.; Blacksburg, Seth R.; Rath, Lynda; Vega, Ana; Fachal, Laura; Gómez-Caamaño, Antonio; De Ruysscher, Dirk; Lammering, Guido; Parliament, Matthew; Blackshaw, Michael; Sia, Michael; Cesaretti, Jamie; Terk, Mitchell; Hixson, Rosetta; Rosenstein, Barry S.; Ostrer, Harry

    2013-01-01

    Background and Purpose Rectal bleeding can occur following radiotherapy for prostate cancer and negatively impacts quality of life for cancer survivors. Treatment and clinical factors do not fully predict for rectal bleeding, and genetic factors may be important. Materials and Methods A genome-wide association study (GWAS) was performed to identify SNPs associated with development of late rectal bleeding following radiotherapy for prostate cancer. Logistic regression was used to test association between 614,453 SNPs and rectal bleeding in a discovery cohort (79 cases, 289 controls), and top-ranking SNPs were tested in a replication cohort (108 cases, 673 controls) from four independent sites. Results rs7120482 and rs17630638, which tag a single locus on chromosome 11q14.3, reached genome-wide significance for association with rectal bleeding (combined p-values 5.4×10−8 and 6.9×10−7 respectively). Several other SNPs had p-values trending towards genome-wide significance, and a polygenic risk score including these SNPs shows a strong rank-correlation with rectal bleeding (Sommers’ d = 5.0×10−12 in the replication cohort). Conclusions This GWAS identified novel genetic markers of rectal bleeding following prostate radiotherapy. These findings could lead to development of a predictive assay to identify patients at risk for this adverse treatment outcome so that dose or treatment modality could be modified. PMID:23719583

  6. Genome-wide association study identifies a region on chromosome 11q14.3 associated with late rectal bleeding following radiation therapy for prostate cancer

    International Nuclear Information System (INIS)

    Background and purpose: Rectal bleeding can occur following radiotherapy for prostate cancer and negatively impacts quality of life for cancer survivors. Treatment and clinical factors do not fully predict rectal bleeding, and genetic factors may be important. Materials and methods: A genome-wide association study (GWAS) was performed to identify SNPs associated with the development of late rectal bleeding following radiotherapy for prostate cancer. Logistic regression was used to test the association between 614,453 SNPs and rectal bleeding in a discovery cohort (79 cases, 289 controls), and top-ranking SNPs were tested in a replication cohort (108 cases, 673 controls) from four independent sites. Results: rs7120482 and rs17630638, which tag a single locus on chromosome 11q14.3, reached genome-wide significance for association with rectal bleeding (combined p-values 5.4 × 10−8 and 6.9 × 10−7 respectively). Several other SNPs had p-values trending toward genome-wide significance, and a polygenic risk score including these SNPs shows a strong rank-correlation with rectal bleeding (Sommers’ d = 5.0 × 10−12 in the replication cohort). Conclusions: This GWAS identified novel genetic markers of rectal bleeding following prostate radiotherapy. These findings could lead to the development of a predictive assay to identify patients at risk for this adverse treatment outcome so that dose or treatment modality could be modified

  7. Microsatellite and single nucleotide polymorphisms in the β-globin locus control region-hypersensitive Site 2: SPECIFICITY of Tunisian βs chromosomes.

    Science.gov (United States)

    Ben Mustapha, Maha; Moumni, Imen; Zorai, Amine; Douzi, Kaïs; Ghanem, Abderraouf; Abbes, Salem

    2012-01-01

    The diversity of sickle cell disease severity is attributed to several cis acting factors, among them the single nucleotide polymorphisms (SNPs) and (AT) rich region in the β-locus control region (β-LCR). This contains five DNase I hypersensitive sites (HS) located 6 to 22 kb upstream to the ϵ gene. The most important of these is the HS2 (5' β-LCR-HS2), characterized by the presence of three different SNPs and a microsatellite region known to be in association with β(S) chromosomes in various populations. The aim of this study was to present the molecular investigation of the 5' β-LCR-HS2 site in normal and sickle cell disease individuals in order to determine if there is any correlation or specificity between these molecular markers, the β(S) Tunisian chromosomes and phenotypical expression of sickle cell disease. One hundred and twenty-four chromosomes from Tunisian individuals (49 β(S) carriers and 13 normal individuals) were screened by polymerase chain reaction (PCR) and sequencing for the polymorphic short tandem microsatellite repeats (AT)(X)N(12)(AT)(Y) and the three SNPs (rs7119428, rs9736333 and rs60240093) of the 5' β-LCR-HS2. Twelve configurations of the microsatellite motif were found with an ancestral configuration elaborated by ClustalW software. Normal and mutated alleles were observed at the homozygous and heterozygous states for the three SNPs. Correlation between microsatellites and SNPs suggests that mutant SNP alleles were mainly associated, in the homozygous sickle cell disease phenotype, with the (AT)(8)N(12)GT(AT)(7) configuration, whereas, normal SNP alleles were associated with the (AT)(X)N(12)(AT)(11) configurations in normal β(A) chromosomes. The correlation of these various configurations with Hb F expression was also investigated. The principal component analysis (PCA) showed the correlation between the homozygous sickle cell disease phenotype, mutated SNP alleles and the Benin microsatellite configuration (AT)(8)N(12)GT

  8. Gametocidal chromosomes enhancing chromosome aberration in common wheat induced by 5-azacytidine.

    Science.gov (United States)

    Su, W-Y; Cong, W-W; Shu, Y-J; Wang, D; Xu, G-H; Guo, C-H

    2013-01-01

    The gametocidal (Gc) chromosome from Aegilops spp induces chromosome mutation, which is introduced into common wheat as a tool of chromosome manipulation for genetic improvement. The Gc chromosome functions similar to a restriction-modification system in bacteria, in which DNA methylation is an important regulator. We treated root tips of wheat carrying Gc chromosomes with the hypomethylation agent 5-azacytidine; chromosome breakage and micronuclei were observed in these root tips. The frequency of aberrations differed in wheat containing different Gc chromosomes, suggesting different functions inducing chromosome breakage. Gc chromosome 3C caused the greatest degree of chromosome aberration, while Gc chromosome 3C(SAT) and 2C caused only slight chromosome aberration. Gc chromosome 3C induced different degrees of chromosome aberration in wheat varieties Triticum aestivum var. Chinese Spring and Norin 26, demonstrating an inhibition function in common wheat. PMID:23884766

  9. Chromosome conservation in squamate reptiles revealed by comparative chromosome painting

    Czech Academy of Sciences Publication Activity Database

    Giovannotti, M.; Pokorná, Martina; Kratochvíl, L.; Caputo, V.; Olmo, E.; Ferguson-Smith, M. A.; Rens, W.

    Manchester : ICCS, 2011. 78-78. [Intarnational Chromosome Conference /18./. 29.08.2011-02.09.2011, Manchester] Institutional research plan: CEZ:AV0Z50450515 Keywords : squamate reptiles Subject RIV: EG - Zoology

  10. Numerous transitions of sex chromosomes in Diptera.

    Directory of Open Access Journals (Sweden)

    Beatriz Vicoso

    2015-04-01

    Full Text Available Many species groups, including mammals and many insects, determine sex using heteromorphic sex chromosomes. Diptera flies, which include the model Drosophila melanogaster, generally have XY sex chromosomes and a conserved karyotype consisting of six chromosomal arms (five large rods and a small dot, but superficially similar karyotypes may conceal the true extent of sex chromosome variation. Here, we use whole-genome analysis in 37 fly species belonging to 22 different families of Diptera and uncover tremendous hidden diversity in sex chromosome karyotypes among flies. We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera. However, we identify species with undifferentiated sex chromosomes, others in which a different chromosome replaced the dot as a sex chromosome or in which up to three chromosomal elements became incorporated into the sex chromosomes, and others yet with female heterogamety (ZW sex chromosomes. Transcriptome analysis shows that dosage compensation has evolved multiple times in flies, consistently through up-regulation of the single X in males. However, X chromosomes generally show a deficiency of genes with male-biased expression, possibly reflecting sex-specific selective pressures. These species thus provide a rich resource to study sex chromosome biology in a comparative manner and show that similar selective forces have shaped the unique evolution of sex chromosomes in diverse fly taxa.

  11. Association of Five SNPs at the PARK16 locus as a Susceptibility Locus with Parkinson's Disease for Forensic Application

    Institute of Scientific and Technical Information of China (English)

    CUI Hong-gang; TIAN Xiao-fei; LUO Xiao-guang; LI Feng-rui; ZHU Lan-hui; ZHOU Yi-shu; REN Yan

    2013-01-01

    To investigate the association of five SNPs (rs823083,rs708723,rs4951261,rs823076 and rs16856110) at the PARK16 locus with Parkinson's disease (PD),and to potentiate its forensic application.The genomic DNAs of 215 PD patients and 212 matched controls from the northern Han Chinese population were amplified in two independent PCR systems and subsequently genotyped by digestion with the three endonucleases (Hinf Ⅰ,Nco Ⅰ and Msp Ⅰ).The genetic parameters and association studies were carried out with SPSS 13.0,Haploview version 4.2 and PLINK 1.07 sofiwares.We detected accurately all genotypes in the five SNPs with multiplex PCR-RFLP and mismatched multiplex PCR-RFLP techniques.The genotypes of four SNPs,except for rs823083,were in Hardy-Weinberg equilibrium.The four SNPs,rs16856110,rs4951261,rs708723 and rs823076,which were in linkage equilibrium,should not be associated with PD (P-values ranging from 0.077 to 0.544).The SNPs investigated at the PARK16 locus were not found to be involved in PD-associated blocks in the northern Han Chinese population.The allele distributions of rs708723,rs4951261,rs823076 and rs16856110 in the northern Han Chinese population can be highly polymorphic,which can be applied to genetic analvsis and forensic practices.

  12. A Mismatch EndoNuclease Array-Based Methodology (MENA for Identifying Known SNPs or Novel Point Mutations

    Directory of Open Access Journals (Sweden)

    Josep M. Comeron

    2016-04-01

    Full Text Available Accurate and rapid identification or confirmation of single nucleotide polymorphisms (SNPs, point mutations and other human genomic variation facilitates understanding the genetic basis of disease. We have developed a new methodology (called MENA (Mismatch EndoNuclease Array pairing DNA mismatch endonuclease enzymology with tiling microarray hybridization in order to genotype both known point mutations (such as SNPs as well as identify previously undiscovered point mutations and small indels. We show that our assay can rapidly genotype known SNPs in a human genomic DNA sample with 99% accuracy, in addition to identifying novel point mutations and small indels with a false discovery rate as low as 10%. Our technology provides a platform for a variety of applications, including: (1 genotyping known SNPs as well as confirming newly discovered SNPs from whole genome sequencing analyses; (2 identifying novel point mutations and indels in any genomic region from any organism for which genome sequence information is available; and (3 screening panels of genes associated with particular diseases and disorders in patient samples to identify causative mutations. As a proof of principle for using MENA to discover novel mutations, we report identification of a novel allele of the beethoven (btv gene in Drosophila, which encodes a ciliary cytoplasmic dynein motor protein important for auditory mechanosensation.

  13. Bioinformatics Approach for Prediction of Functional Coding/Noncoding Simple Polymorphisms (SNPs/Indels) in Human BRAF Gene

    Science.gov (United States)

    Omer, Shaza E.; Khalf-allah, Rahma M.; Mustafa, Razaz Y.; Ali, Isra S.; Mohamed, Sofia B.

    2016-01-01

    This study was carried out for Homo sapiens single variation (SNPs/Indels) in BRAF gene through coding/non-coding regions. Variants data was obtained from database of SNP even last update of November, 2015. Many bioinformatics tools were used to identify functional SNPs and indels in proteins functions, structures and expressions. Results shown, for coding polymorphisms, 111 SNPs predicted as highly damaging and six other were less. For UTRs, showed five SNPs and one indel were altered in micro RNAs binding sites (3′ UTR), furthermore nil SNP or indel have functional altered in transcription factor binding sites (5′ UTR). In addition for 5′/3′ splice sites, analysis showed that one SNP within 5′ splice site and one Indel in 3′ splice site showed potential alteration of splicing. In conclude these previous functional identified SNPs and indels could lead to gene alteration, which may be directly or indirectly contribute to the occurrence of many diseases. PMID:27478437

  14. Genetic polymorphism of human Y chromosome and risk factors for cardiovascular diseases: a study in WOBASZ cohort.

    Directory of Open Access Journals (Sweden)

    Grażyna Kostrzewa

    Full Text Available Genetic variants of Y chromosome predispose to hypertension in rodents, whereas in humans the evidence is conflicting. Our purpose was to study the distribution of a panel of Y chromosome markers in a cohort from a cross-sectional population-based study on the prevalence of cardiovascular risk factors in Poland (WOBASZ study. The HindIII, YAP Y chromosome variants, previously shown to influence blood pressure, lipid traits or height, as well as SNPs defining main Y chromosome haplogroups, were typed in 3026, 2783 and 2652 samples, respectively. In addition, 4 subgroups (N~100 each representing extremes of LDL concentration or blood pressure (BP were typed for a panel of 17 STRs. The HindIII and YAP polymorphism were not associated with any of the studied traits. Analysis of the haplogroup distribution showed an association between higher HDL level and hg I-M170 (P = 0.02, higher LDL level and hg F*(xI-M170, J2-M172, K-M9 (P = 0.03 and lower BMI and hg N3-Tat (P = 0.04. Analysis of STRs did not show statistically significant differences. Since all these associations lost statistical significance after Bonferroni correction, we conclude that a major role of Y chromosome genetic variation (defined by HindIII, YAP or main Y chromosome haplogroups in determining cardiovascular risk in Poles is unlikely.

  15. Familial transmission of a deletion of chromosome 21 derived from a translocation between chromosome 21 and an inverted chromosome 22.

    Science.gov (United States)

    Aviv, H; Lieber, C; Yenamandra, A; Desposito, F

    1997-06-27

    Chromosome analysis of a newborn boy with Down syndrome resulted in the identification of a family with an unusual derivative chromosome 22. The child has 46 chromosomes, including two chromosomes 21, one normal chromosome 22, and a derivative chromosome 22. Giemsa banding and fluorescent in situ hybridization (FISH) studies show that the derivative chromosome is chromosome 22 with evidence of both paracentric and pericentric inversions, joined to the long arm of chromosome 21 from 21q21.2 to qter. The rearrangement results in partial trisomy 21 extending from 21q21.2 to 21q terminus in the patient. The child's mother, brother, maternal aunt, and maternal grandmother are all carriers of the derivative chromosome. All have 45 chromosomes, with one normal chromosome 21, one normal chromosome 22, and the derivative chromosome 22. The rearrangement results in the absence of the short arm, the centromere, and the proximal long arm of chromosome 21 (del 21pter-21q21.2) in carriers. Carriers of the derivative chromosome in this family have normal physical appearance, mild learning disabilities and poor social adjustment. PMID:9182781

  16. Meiosis and chromosome painting of sex chromosome systems in Ceboidea.

    Science.gov (United States)

    Mudry, M D; Rahn, I M; Solari, A J

    2001-06-01

    The identity of the chromosomes involved in the multiple sex system of Alouatta caraya (Aca) and the possible distribution of this system among other Ceboidea were investigated by chromosome painting of mitotic cells from five species and by analysis of meiosis at pachytene in two species. The identity of the autosome #7 (X2) involved in the multiple system of Aca and its breakage points were demonstrated by both meiosis and chromosome painting. These features are identical to those described by Consigliere et al. [1996] in Alouatta seniculus sara (Assa) and Alouatta seniculus arctoidea (Asar). This multiple system was absent in the other four Ceboidea species studied here. However, data from the literature strongly suggest the presence of this multiple in other members of this genus. The presence of this multiple system among several species and subspecies that show high levels of chromosome rearrangements may suggest a special selective value of this multiple. The meiotic features of the sex systems of Aca and Cebus apella paraguayanus (Cap) are strikingly different at pachytene, as the latter system is similar to the sex pair of man and other primates. The relatively large genetic distances between species presently showing this multiple system suggest that its origin is not recent. Other members of the same genus should be investigated at meiosis and by chromosome painting in order to know the extent and distribution of this complex sex-chromosome system. PMID:11376445

  17. A genome-wide association study identifies pancreatic cancer susceptibility loci on chromosomes 13q22.1, 1q32.1 and 5p15.33

    OpenAIRE

    Petersen, Gloria M.; Amundadottir, Laufey; Fuchs, Charles S; Kraft, Peter; Stolzenberg-Solomon, Rachael Z; Jacobs, Kevin B.; Arslan, Alan A.; Bueno-de-Mesquita, H Bas; Gallinger, Steven; Gross, Myron; Helzlsouer, Kathy; Holly, Elizabeth A.; Jacobs, Eric J.; Klein, Alison P; LaCroix, Andrea

    2010-01-01

    We conducted a genome-wide association study (GWAS) of pancreatic cancer in 3,851 cases and 3,934 controls drawn from twelve prospective cohort studies and eight case-control studies. Based on a logistic regression model for genotype trend effect that was adjusted for study, age, sex, self-described ancestry and five principal components, we identified eight SNPs that map to three loci on chromosomes 13q22.1, 1q32.1 and 5p15.33. Two correlated SNPs, rs9543325 (P=3.27×10−11; per allele odds ra...

  18. Tracking chromosomal positions of oligomers - a case study with Illumina's BovineSNP50 beadchip

    Directory of Open Access Journals (Sweden)

    Brockmann Gudrun A

    2010-02-01

    Full Text Available Abstract Background High density genotyping arrays have become established as a valuable research tool in human genetics. Currently, more than 300 genome wide association studies were published for human reporting about 1,000 SNPs that are associated with a phenotype. Also in animal sciences high density genotyping arrays are harnessed to analyse genetic variation. To exploit the full potential of this technology single nucleotide polymorphisms (SNPs on the chips should be well characterized and their chromosomal position should be precisely known. This, however, is a challenge if the genome sequence is still subject to changes. Results We have developed a mapping strategy and a suite of software scripts to update the chromosomal positions of oligomer sequences used for SNP genotyping on high density arrays. We describe the mapping procedure in detail so that scientists with moderate bioinformatics skills can reproduce it. We furthermore present a case study in which we re-mapped 54,001 oligomer sequences from Ilumina's BovineSNP50 beadchip to the bovine genome sequence. We found in 992 cases substantial discrepancies between the manufacturer's annotations and our results. The software scripts in the Perl and R programming languages are provided as supplements. Conclusions The positions of oligomer sequences in the genome are volatile even within one build of the genome. To facilitate the analysis of data from a GWAS or from an expression study, especially with species whose genome assembly is still unstable, it is recommended to update the oligomer positions before data analysis.

  19. Linkage disequilibrium blocks, haplotype structure, and htSNPs of human CYP7A1 gene

    Directory of Open Access Journals (Sweden)

    Wan Yu-Jui

    2006-05-01

    Full Text Available Abstract Background Cholesterol 7-alpha-hydroxylase (CYP7A1 is the rate limiting enzyme for converting cholesterol into bile acids. Genetic variations in the CYP7A1 gene have been associated with metabolic disorders of cholesterol and bile acids, including hypercholesterolemia, hypertriglyceridemia, arteriosclerosis, and gallstone disease. Current genetic studies are focused mainly on analysis of a single nucleotide polymorphism (SNP at A-278C in the promoter region of the CYP7A1 gene. Here we report a genetic approach for an extensive analysis on linkage disequilibrium (LD blocks and haplotype structures of the entire CYP7A1 gene and its surrounding sequences in Africans, Caucasians, Asians, Mexican-Americans, and African-Americans. Result The LD patterns and haplotype blocks of CYP7A1 gene were defined in Africans, Caucasians, and Asians using genotyping data downloaded from the HapMap database to select a set of haplotype-tagging SNPs (htSNP. A low cost, microarray-based platform on thin-film biosensor chips was then developed for high-throughput genotyping to study transferability of the HapMap htSNPs to Mexican-American and African-American populations. Comparative LD patterns and haplotype block structure was defined across all test populations. Conclusion A constant genetic structure in CYP7A1 gene and its surrounding sequences was found that may lead to a better design for association studies of genetic variations in CYP7A1 gene with cholesterol and bile acid metabolism.

  20. Comparison of family history and SNPs for predicting risk of complex disease.

    Science.gov (United States)

    Do, Chuong B; Hinds, David A; Francke, Uta; Eriksson, Nicholas

    2012-01-01

    The clinical utility of family history and genetic tests is generally well understood for simple Mendelian disorders and rare subforms of complex diseases that are directly attributable to highly penetrant genetic variants. However, little is presently known regarding the performance of these methods in situations where disease susceptibility depends on the cumulative contribution of multiple genetic factors of moderate or low penetrance. Using quantitative genetic theory, we develop a model for studying the predictive ability of family history and single nucleotide polymorphism (SNP)-based methods for assessing risk of polygenic disorders. We show that family history is most useful for highly common, heritable conditions (e.g., coronary artery disease), where it explains roughly 20%-30% of disease heritability, on par with the most successful SNP models based on associations discovered to date. In contrast, we find that for diseases of moderate or low frequency (e.g., Crohn disease) family history accounts for less than 4% of disease heritability, substantially lagging behind SNPs in almost all cases. These results indicate that, for a broad range of diseases, already identified SNP associations may be better predictors of risk than their family history-based counterparts, despite the large fraction of missing heritability that remains to be explained. Our model illustrates the difficulty of using either family history or SNPs for standalone disease prediction. On the other hand, we show that, unlike family history, SNP-based tests can reveal extreme likelihood ratios for a relatively large percentage of individuals, thus providing potentially valuable adjunctive evidence in a differential diagnosis. PMID:23071447

  1. The more the merrier? How a few SNPs predict pigmentation phenotypes in the Northern German population.

    Science.gov (United States)

    Caliebe, Amke; Harder, Melanie; Schuett, Rebecca; Krawczak, Michael; Nebel, Almut; von Wurmb-Schwark, Nicole

    2016-05-01

    Human pigmentation traits are of great interest to many research areas, from ancient DNA analysis to forensic science. We developed a gene-based predictive model for pigmentation phenotypes in a realistic target population for forensic case work from Northern Germany and compared our model with those brought forth by previous studies of genetically more heterogeneous populations. In doing so, we aimed at answering the following research questions: (1) do existing models allow good prediction of high-quality phenotypes in a genetically similar albeit more homogeneous population? (2) Would a model specifically set up for the more homogeneous population perform notably better than existing models? (3) Can the number of markers included in existing models be reduced without compromising their predictive capability in the more homogenous population? We investigated the association between eye, hair and skin colour and 12 candidate single-nucleotide polymorphisms (SNPs) from six genes. Our study comprised two samples of 300 and 100 individuals from Northern Germany. SNP rs12913832 in HERC2 was found to be strongly associated with blue eye colour (odds ratio=40.0, Pyield moderate predictive power (AUC: 77%; sensitivity: 90%, specificity: 63%, both at a 0.5 threshold for blue eye colour probability). SNP associations with hair and skin colour were weaker and genotypes less predictive. A comparison with two recently published sets of markers to predict eye and hair colour revealed that the consideration of additional SNPs with weak-to-moderate effect increased the predictive power for eye colour, but not for hair colour. PMID:26286644

  2. Association of CAPN10 SNPs and haplotypes with polycystic ovary syndrome among South Indian Women.

    Directory of Open Access Journals (Sweden)

    Shilpi Dasgupta

    Full Text Available Polycystic Ovary Syndrome (PCOS is known to be characterized by metabolic disorder in which hyperinsulinemia and peripheral insulin resistance are central features. Given the physiological overlap between PCOS and type-2 diabetes (T2DM, and calpain 10 gene (CAPN10 being a strong candidate for T2DM, a number of studies have analyzed CAPN10 SNPs among PCOS women yielding contradictory results. Our study is first of its kind to investigate the association pattern of CAPN10 polymorphisms (UCSNP-44, 43, 56, 19 and 63 with PCOS among Indian women. 250 PCOS cases and 299 controls from Southern India were recruited for this study. Allele and genotype frequencies of the SNPs were determined and compared between the cases and controls. Results show significant association of UCSNP-44 genotype CC with PCOS (p = 0.007 with highly significant odds ratio when compared to TC (OR = 2.51, p = 0.003, 95% CI = 1.37-4.61 as well as TT (OR = 1.94, p = 0.016, 95% CI = 1.13-3.34. While the haplotype carrying the SNP-44 and SNP-19 variants (21121 exhibited a 2 fold increase in the risk for PCOS (OR = 2.37, p = 0.03, the haplotype containing SNP-56 and SNP-19 variants (11221 seems to have a protective role against PCOS (OR = 0.20, p = 0.004. Our results support the earlier evidence for a possible role of UCSNP-44 of the CAPN10 gene in the manifestation of PCOS.

  3. The evolutionary history of Afrocanarian blue tits inferred from genomewide SNPs.

    Science.gov (United States)

    Gohli, Jostein; Leder, Erica H; Garcia-Del-Rey, Eduardo; Johannessen, Lars Erik; Johnsen, Arild; Laskemoen, Terje; Popp, Magnus; Lifjeld, Jan T

    2015-01-01

    A common challenge in phylogenetic reconstruction is to find enough suitable genomic markers to reliably trace splitting events with short internodes. Here, we present phylogenetic analyses based on genomewide single-nucleotide polymorphisms (SNPs) of an enigmatic avian radiation, the subspecies complex of Afrocanarian blue tits (Cyanistes teneriffae). The two sister species, the Eurasian blue tit (Cyanistes caeruleus) and the azure tit (Cyanistes cyanus), constituted the out-group. We generated a large data set of SNPs for analysis of population structure and phylogeny. We also adapted our protocol to utilize degraded DNA from old museum skins from Libya. We found strong population structuring that largely confirmed subspecies monophyly and constructed a coalescent-based phylogeny with full support at all major nodes. The results are consistent with a recent hypothesis that La Palma and Libya are relic populations of an ancient Afrocanarian blue tit, although a small data set for Libya could not resolve its position relative to La Palma. The birds on the eastern islands of Fuerteventura and Lanzarote are similar to those in Morocco. Together they constitute the sister group to the clade containing the other Canary Islands (except La Palma), in which El Hierro is sister to the three central islands. Hence, extant Canary Islands populations seem to originate from multiple independent colonization events. We also found population divergences in a key reproductive trait, viz. sperm length, which may constitute reproductive barriers between certain populations. We recommend a taxonomic revision of this polytypic species, where several subspecies should qualify for species rank. PMID:25407440

  4. Allelic Spectra of Risk SNPs Are Different for Environment/Lifestyle Dependent versus Independent Diseases.

    Directory of Open Access Journals (Sweden)

    Ivan P Gorlov

    2015-07-01

    Full Text Available Genome-wide association studies (GWAS have generated sufficient data to assess the role of selection in shaping allelic diversity of disease-associated SNPs. Negative selection against disease risk variants is expected to reduce their frequencies making them overrepresented in the group of minor (<50% alleles. Indeed, we found that the overall proportion of risk alleles was higher among alleles with frequency <50% (minor alleles compared to that in the group of major alleles. We hypothesized that negative selection may have different effects on environment (or lifestyle-dependent versus environment (or lifestyle-independent diseases. We used an environment/lifestyle index (ELI to assess influence of environmental/lifestyle factors on disease etiology. ELI was defined as the number of publications mentioning "environment" or "lifestyle" AND disease per 1,000 disease-mentioning publications. We found that the frequency distributions of the risk alleles for the diseases with strong environmental/lifestyle components follow the distribution expected under a selectively neutral model, while frequency distributions of the risk alleles for the diseases with weak environmental/lifestyle influences is shifted to the lower values indicating effects of negative selection. We hypothesized that previously selectively neutral variants become risk alleles when environment changes. The hypothesis of ancestrally neutral, currently disadvantageous risk-associated alleles predicts that the distribution of risk alleles for the environment/lifestyle dependent diseases will follow a neutral model since natural selection has not had enough time to influence allele frequencies. The results of our analysis suggest that prediction of SNP functionality based on the level of evolutionary conservation may not be useful for SNPs associated with environment/lifestyle dependent diseases.

  5. Chromosome fragility in Freemartin cattle

    Directory of Open Access Journals (Sweden)

    V. Barbieri

    2010-04-01

    Full Text Available The aim of the present study was to verify chromosome fragility in freemartin cattle using chromosome aberration (CA and sister chromatid exchange (SCE tests. A total of eighteen co-twins were investigated. Fourteen animals were identified as cytogenetically chimeric (2n=60, XX/XY while 4 were classified as normal. Freemartin cattle showed a higher percentage of aneuploid cells (18.64% and highly significant statistical differences (P < 0.001 in mean values of gaps (4.53 ± 2.05, chromatid breaks (0.26 ± 0.51, and significant statistical differences (P < 0.005 in mean values of chromosome breaks (0.12 ± 0.43 when compared to 10 control animals from single births (aneuploid cells, 11.20%; gaps, 2.01 ± 1.42; chromatid breaks, 0.05 ± 0.22; chromosome breaks, 0.02 ± 0.14.

  6. The identification of trans-associations between prostate cancer GWAS SNPs and RNA expression differences in tumor-adjacent stroma

    Science.gov (United States)

    Chen, Xin; McClelland, Michael; Jia, Zhenyu; Rahmatpanah, Farah B.; Sawyers, Anne; Trent, Jeffrey; Duggan, David; Mercola, Dan

    2015-01-01

    Here we tested the hypothesis that SNPs associated with prostate cancer risk, might differentially affect RNA expression in prostate cancer stroma. The most significant 35 SNP loci were selected from Genome Wide Association (GWA) studies of ~40,000 patients. We also selected 4030 transcripts previously associated with prostate cancer diagnosis and prognosis. eQTL analysis was carried out by a modified BAYES method to analyze the associations between the risk variants and expressed transcripts jointly in a single model. We observed 47 significant associations between eight risk variants and the expression patterns of 46 genes. This is the first study to identify associations between multiple SNPs and multiple in trans gene expression differences in cancer stroma. Potentially, a combination of SNPs and associated expression differences in prostate stroma may increase the power of risk assessment for individuals, and for cancer progression. PMID:25638161

  7. Prediction of Disease Causing Non-Synonymous SNPs by the Artificial Neural Network Predictor NetDiseaseSNP

    DEFF Research Database (Denmark)

    Johansen, Morten Bo; Gonzalez-Izarzugaza, Jose Maria; Brunak, Søren;

    2013-01-01

    We have developed a sequence conservation-based artificial neural network predictor called NetDiseaseSNP which classifies nsSNPs as disease-causing or neutral. Our method uses the excellent alignment generation algorithm of SIFT to identify related sequences and a combination of 31 features...... assessing sequence conservation and the predicted surface accessibility to produce a single score which can be used to rank nsSNPs based on their potential to cause disease. NetDiseaseSNP classifies successfully disease-causing and neutral mutations. In addition, we show that NetDiseaseSNP discriminates...... cancer driver and passenger mutations satisfactorily. Our method outperforms other state-of-the-art methods on several disease/neutral datasets as well as on cancer driver/passenger mutation datasets and can thus be used to pinpoint and prioritize plausible disease candidates among nsSNPs for further...

  8. Cost-effective multiplexing before capture allows screening of 25 000 clinically relevant SNPs in childhood acute lymphoblastic leukemia

    DEFF Research Database (Denmark)

    Wesolowska, Agata; Dalgaard, M. D.; Borst, L.;

    2011-01-01

    Genetic variants, including single-nucleotide polymorphisms (SNPs), are key determiners of interindividual differences in treatment efficacy and toxicity in childhood acute lymphoblastic leukemia (ALL). Although up to 13 chemotherapeutic agents are used in the treatment of this cancer, it remains a...... model disease for exploring the impact of genetic variation due to well-characterized cytogenetics, drug response pathways and precise monitoring of minimal residual disease. Here, we have selected clinically relevant genes and SNPs through literature screening, and on the basis of associations with key...... designed a cost-effective, high-throughput capture assay of â¼25â000 clinically relevant SNPs, and demonstrated that multiple samples can be tagged and pooled before genome capture in targeted enrichment with a sufficient sequencing depth for genotyping. This multiplexed, targeted sequencing method allows...

  9. Identification of SNPs in barley(Hordeum vulgare L.)by deep sequencing of six reduced representation libraries

    Institute of Scientific and Technical Information of China (English)

    Ganggang; Guo; Dawa; Dondup; Lisha; Zhang; Sha; Hu; Xingmiao; Yuan; Jing; Zhang

    2014-01-01

    High-density genetic markers are required for genotyping and linkage mapping in identifying genes from crops with complex genomes, such as barley. As the most common variation, single nucleotide polymorphisms(SNPs) are suitable for accurate genotyping by using the next-generation sequencing(NGS) technology. Reduced representation libraries(RRLs) of five barley accessions and one mutant were sequenced using NGS technology for SNP discovery. Twenty million short reads were generated and the proportion of repetitive sequences was reduced by more than 56%. A total of 6061 SNPs were identified, and 451 were mapped to the draft sequence of the barley genome with pairing reads. Eleven SNPs were validated using length polymorphic allele-specific PCR markers.

  10. Methods for chromosome-specific staining

    Science.gov (United States)

    Gray, Joe W.; Pinkel, Daniel

    1995-01-01

    Methods and compositions for chromosome-specific staining are provided. Compositions comprise heterogenous mixtures of labeled nucleic acid fragments having substantially complementary base sequences to unique sequence regions of the chromosomal DNA for which their associated staining reagent is specific. Methods include methods for making the chromosome-specific staining compositions of the invention, and methods for applying the staining compositions to chromosomes.

  11. Recent Y chromosome divergence despite ancient origin of dioecy in poplars (Populus).

    Science.gov (United States)

    Geraldes, A; Hefer, C A; Capron, A; Kolosova, N; Martinez-Nuñez, F; Soolanayakanahally, R Y; Stanton, B; Guy, R D; Mansfield, S D; Douglas, C J; Cronk, Q C B

    2015-07-01

    All species of the genus Populus (poplar, aspen) are dioecious, suggesting an ancient origin of this trait. Despite some empirical counter examples, theory suggests that nonrecombining sex-linked regions should quickly spread, eventually becoming heteromorphic chromosomes. In contrast, we show using whole-genome scans that the sex-associated region in Populus trichocarpa is small and much younger than the age of the genus. This indicates that sex determination is highly labile in poplar, consistent with recent evidence of 'turnover' of sex-determination regions in animals. We performed whole-genome resequencing of 52 P. trichocarpa (black cottonwood) and 34 Populus balsamifera (balsam poplar) individuals of known sex. Genomewide association studies in these unstructured populations identified 650 SNPs significantly associated with sex. We estimate the size of the sex-linked region to be ~100 kbp. All SNPs significantly associated with sex were in strong linkage disequilibrium despite the fact that they were mapped to six different chromosomes (plus 3 unmapped scaffolds) in version 2.2 of the reference genome. We show that this is likely due to genome misassembly. The segregation pattern of sex-associated SNPs revealed this to be an XY sex-determining system. Estimated divergence times of X and Y haplotype sequences (6-7 Ma) are much more recent than the divergence of P. trichocarpa (poplar) and Populus tremuloides (aspen). Consistent with this, in P. tremuloides, we found no XY haplotype divergence within the P. trichocarpa sex-determining region. These two species therefore have a different genomic architecture of sex, suggestive of at least one turnover event in the recent past. PMID:25728270

  12. Chromosome Architecture and Genome Organization

    OpenAIRE

    Giorgio Bernardi

    2015-01-01

    How the same DNA sequences can function in the three-dimensional architecture of interphase nucleus, fold in the very compact structure of metaphase chromosomes and go precisely back to the original interphase architecture in the following cell cycle remains an unresolved question to this day. The strategy used to address this issue was to analyze the correlations between chromosome architecture and the compositional patterns of DNA sequences spanning a size range from a few hundreds to a few...

  13. Chromosome evolution in Neotropical butterflies

    OpenAIRE

    Saura, Anssi; Von Schoultz, Barbara; Saura, Anja O.; Brown, Keith S., Jr.

    2013-01-01

    We list the chromosome numbers for 65 species of Neotropical Hesperiidae and 104 species or subspecies of Pieridae. In Hesperiidae the tribe Pyrrhopygini have a modal n = 28, Eudaminae and Pyrgini a modal n = 31, while Hesperiinae have n = around 29. Among Pieridae, Coliadinae have a strong modal n = 31 and among Pierinae Anthocharidini are almost fixed for n = 15 while Pierini vary with n = 26 as the most common chromosome number. Dismorphiinae show wide variation. We discuss these results i...

  14. SNPs in genes implicated in radiation response are associated with radiotoxicity and evoke roles as predictive and prognostic biomarkers

    International Nuclear Information System (INIS)

    Biomarkers are needed to individualize cancer radiation treatment. Therefore, we have investigated the association between various risk factors, including single nucleotide polymorphisms (SNPs) in candidate genes and late complications to radiotherapy in our nasopharyngeal cancer patients. A cohort of 155 patients was included. Normal tissue fibrosis was scored using RTOG/EORTC grading system. A total of 45 SNPs in 11 candidate genes (ATM, XRCC1, XRCC3, XRCC4, XRCC5, PRKDC, LIG4, TP53, HDM2, CDKN1A, TGFB1) were genotyped by direct genomic DNA sequencing. Patients with severe fibrosis (cases, G3-4, n = 48) were compared to controls (G0-2, n = 107). Univariate analysis showed significant association (P < 0.05) with radiation complications for 6 SNPs (ATM G/A rs1801516, HDM2 promoter T/G rs2279744 and T/A rs1196333, XRCC1 G/A rs25487, XRCC5 T/C rs1051677 and TGFB1 C/T rs1800469). In addition, Kaplan-Meier analyses have also highlighted significant association between genotypes and length of patients’ follow-up after radiotherapy. Multivariate logistic regression has further sustained these results suggesting predictive and prognostic roles of SNPs. Univariate and multivariate analysis suggest that radiation toxicity in radiotherapy patients are associated with certain SNPs, in genes including HDM2 promoter studied for the 1st time. These results support the use of SNPs as genetic predictive markers for clinical radiosensitivity and evoke a prognostic role for length of patients’ follow-up after radiotherapy

  15. A framework radiation hybrid map of buffalo chromosome 1 ordering scaffolds from buffalo genome sequence assembly.

    Science.gov (United States)

    Stafuzza, N B; Naressi, B C M; Yang, E; Cai, J J; Amaral-Trusty, M E J

    2015-01-01

    River buffalo chromosome 1 (BBU1) is a sub-metacentric chromosome homologous to bovine chromosomes 1 and 27. In this study, we constructed a new framework radiation hybrid (RH) map from BBU1 using BBURH5000 panel adding nine new genes (ADRB3, ATP2C1, COPB2, CRYGS, P2RY1, SLC5A3, SLC20A2, SST, and ZDHHC2) and one microsatellite (CSSM043) to the set of markers previously mapped on BBU1. The new framework RH map of BBU1 contained 141 markers (55 genes, 2 ESTs, 10 microsatellites, and 74 SNPs) distributed within one linkage group spanning 2832.62 centirays. Comparison of the RH map to sequences from bovine chromosomes 1 and 27 revealed an inversion close to the telomeric region. In addition, we ordered a set of 34 scaffolds from the buffalo genome assembly UMD_CASPUR_WB_2.0. The RH map could provide a valuable tool to order scaffolds from the buffalo genome sequence, contributing to its annotation. PMID:26535622

  16. Numerically abnormal chromosome constitutions in humans

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    Chapter 24, discusses numerically abnormal chromosome constitutions in humans. This involves abnormalities of human chromosome number, including polyploidy (when the number of sets of chromosomes increases) and aneuploidy (when the number of individual normal chromosomes changes). Chapter sections discuss the following chromosomal abnormalities: human triploids, imprinting and uniparental disomy, human tetraploids, hydatidiform moles, anomalies caused by chromosomal imbalance, 13 trisomy (D{sub 1} trisomy, Patau syndrome), 21 trisomy (Down syndrome), 18 trisomy syndrome (Edwards syndrome), other autosomal aneuploidy syndromes, and spontaneous abortions. The chapter concludes with remarks on the nonrandom participation of chromosomes in trisomy. 69 refs., 3 figs., 4 tabs.

  17. Chromosome evolution in Neotropical butterflies.

    Science.gov (United States)

    Saura, Anssi; Von Schoultz, Barbara; Saura, Anja O; Brown, Keith S

    2013-06-01

    We list the chromosome numbers for 65 species of Neotropical Hesperiidae and 104 species or subspecies of Pieridae. In Hesperiidae the tribe Pyrrhopygini have a modal n = 28, Eudaminae and Pyrgini a modal n = 31, while Hesperiinae have n = around 29. Among Pieridae, Coliadinae have a strong modal n = 31 and among Pierinae Anthocharidini are almost fixed for n = 15 while Pierini vary with n = 26 as the most common chromosome number. Dismorphiinae show wide variation. We discuss these results in the context of chromosome numbers of over 1400 Neotropical butterfly species and subspecies derived from about 3000 populations published here and in earlier papers of a series. The overall results show that many Neotropical groups are characterized by karyotype instability with several derived modal numbers or none at all, while almost all taxa of Lepidoptera studied from the other parts of the world have one of n = 29-31 as modal numbers. Possibly chromosome number changes become fixed in the course of speciation driven by biotic interactions. Population subdivision and structuring facilitate karyotype change. Factors that stabilize chromosome numbers include hybridization among species sharing the same number, migration, sexual selection and possibly the distribution of chromosomes within the nucleus. PMID:23865963

  18. Chromosome Architecture and Genome Organization

    Science.gov (United States)

    Bernardi, Giorgio

    2015-01-01

    How the same DNA sequences can function in the three-dimensional architecture of interphase nucleus, fold in the very compact structure of metaphase chromosomes and go precisely back to the original interphase architecture in the following cell cycle remains an unresolved question to this day. The strategy used to address this issue was to analyze the correlations between chromosome architecture and the compositional patterns of DNA sequences spanning a size range from a few hundreds to a few thousands Kilobases. This is a critical range that encompasses isochores, interphase chromatin domains and boundaries, and chromosomal bands. The solution rests on the following key points: 1) the transition from the looped domains and sub-domains of interphase chromatin to the 30-nm fiber loops of early prophase chromosomes goes through the unfolding into an extended chromatin structure (probably a 10-nm “beads-on-a-string” structure); 2) the architectural proteins of interphase chromatin, such as CTCF and cohesin sub-units, are retained in mitosis and are part of the discontinuous protein scaffold of mitotic chromosomes; 3) the conservation of the link between architectural proteins and their binding sites on DNA through the cell cycle explains the “mitotic memory” of interphase architecture and the reversibility of the interphase to mitosis process. The results presented here also lead to a general conclusion which concerns the existence of correlations between the isochore organization of the genome and the architecture of chromosomes from interphase to metaphase. PMID:26619076

  19. APCR, factor V gene known and novel SNPs and adverse pregnancy outcomes in an Irish cohort of pregnant women

    LENUS (Irish Health Repository)

    Sedano-Balbas, Sara

    2010-03-10

    Abstract Background Activated Protein C Resistance (APCR), a poor anticoagulant response of APC in haemostasis, is the commonest heritable thrombophilia. Adverse outcomes during pregnancy have been linked to APCR. This study determined the frequency of APCR, factor V gene known and novel SNPs and adverse outcomes in a group of pregnant women. Methods Blood samples collected from 907 pregnant women were tested using the Coatest® Classic and Modified functional haematological tests to establish the frequency of APCR. PCR-Restriction Enzyme Analysis (PCR-REA), PCR-DNA probe hybridisation analysis and DNA sequencing were used for molecular screening of known mutations in the factor V gene in subjects determined to have APCR based on the Coatest® Classic and\\/or Modified functional haematological tests. Glycosylase Mediated Polymorphism Detection (GMPD), a SNP screening technique and DNA sequencing, were used to identify SNPs in the factor V gene of 5 APCR subjects. Results Sixteen percent of the study group had an APCR phenotype. Factor V Leiden (FVL), FV Cambridge, and haplotype (H) R2 alleles were identified in this group. Thirty-three SNPs; 9 silent SNPs and 24 missense SNPs, of which 20 SNPs were novel, were identified in the 5 APCR subjects. Adverse pregnancy outcomes were found at a frequency of 35% in the group with APCR based on Classic Coatest® test only and at 45% in the group with APCR based on the Modified Coatest® test. Forty-eight percent of subjects with FVL had adverse outcomes while in the group of subjects with no FVL, adverse outcomes occurred at a frequency of 37%. Conclusions Known mutations and novel SNPs in the factor V gene were identified in the study cohort determined to have APCR in pregnancy. Further studies are required to investigate the contribution of these novel SNPs to the APCR phenotype. Adverse outcomes including early pregnancy loss (EPL), preeclampsia (PET) and intrauterine growth restriction (IGUR) were not significantly more

  20. Role of plasma matrix-metalloproteases (MMPs) and their polymorphisms (SNPs) in sepsis development and outcome in ICU patients

    OpenAIRE

    Guadalupe Martin; Víctor Asensi; A. Hugo Montes; Julio Collazos; Victoria Alvarez; Carton, José A.; Francisco Taboada; Eulalia Valle-Garay

    2014-01-01

    Matrix-metalloproteases (MMPs) and their tissue-inhibitors (TIMPs), modulated by different single nucleotide polymorphisms (SNPs), are critical in sepsis development. Ninety ICU severely septic and 91 ICU uninfected patients were prospectively studied. MMP-1 (−1607 1G/2G), MMP-3 (−1612 5A/6A), MMP-8 (−799 C/T), MMP-9 (−1562 C/T), and MMP-13 (−77A/G) SNPs were genotyped. Plasma MMPs (-1, -2, -3, -8, -9, -10, -13) and TIMPs (-1,-2,-4) were measured. AA homozygotes and A allele carriers of MMP-1...

  1. Mutations and/or close relatives? Six case work examples where 49 autosomal SNPs were used as supplementary markers

    DEFF Research Database (Denmark)

    Børsting, Claus; Morling, Niels

    2011-01-01

    Six case work examples are presented, where the individuals were typed for 15 autosomal short tandem repeats (STRs) and 49 autosomal single nucleotide polymorphisms (SNPs). The 15 STRs were typed with the AmpFlSTR Identifiler PCR Amplification Kit and the 49 SNPs were typed with the SNPfor...... father would have been falsely included based on the STR results, while the SNP results showed that the alleged father was not the true parent. These case work examples underline the importance of performing supplementary investigations in selected cases and demonstrate the usefulness of the SNPfor...

  2. Evolution of Sex Chromosomes in Insects

    OpenAIRE

    Kaiser, Vera B; Bachtrog, Doris

    2010-01-01

    Sex chromosomes have many unusual features relative to autosomes. Y (or W) chromosomes lack genetic recombination, are male- (female-) limited, and show an abundance of genetically inert heterochromatic DNA but contain few functional genes. X (or Z) chromosomes also show sex-biased transmission (i.e., X chromosomes show female-biased and Z-chromosomes show male-biased inheritance) and are hemizygous in the heterogametic sex. Their unusual ploidy level and pattern of inheritance imply that sex...

  3. Structure SNP (StSNP): a web server for mapping and modeling nsSNPs on protein structures with linkage to metabolic pathways

    OpenAIRE

    Uzun, Alper; Leslin, Chesley M.; Abyzov, Alexej; Ilyin, Valentin

    2007-01-01

    SNPs located within the open reading frame of a gene that result in an alteration in the amino acid sequence of the encoded protein [nonsynonymous SNPs (nsSNPs)] might directly or indirectly affect functionality of the protein, alone or in the interactions in a multi-protein complex, by increasing/decreasing the activity of the metabolic pathway. Understanding the functional consequences of such changes and drawing conclusions about the molecular basis of diseases, involves integrating inform...

  4. Exploring the tertiary gene pool of bread wheat: sequence assembly and analysis of chromosome 5M(g) of Aegilops geniculata.

    Science.gov (United States)

    Tiwari, Vijay K; Wang, Shichen; Danilova, Tatiana; Koo, Dal Hoe; Vrána, Jan; Kubaláková, Marie; Hribova, Eva; Rawat, Nidhi; Kalia, Bhanu; Singh, Narinder; Friebe, Bernd; Doležel, Jaroslav; Akhunov, Eduard; Poland, Jesse; Sabir, Jamal S M; Gill, Bikram S

    2015-11-01

    Next-generation sequencing (NGS) provides a powerful tool for the discovery of important genes and alleles in crop plants and their wild relatives. Despite great advances in NGS technologies, whole-genome shotgun sequencing is cost-prohibitive for species with complex genomes. An attractive option is to reduce genome complexity to a single chromosome prior to sequencing. This work describes a strategy for studying the genomes of distant wild relatives of wheat by isolating single chromosomes from addition or substitution lines, followed by chromosome sorting using flow cytometry and sequencing of chromosomal DNA by NGS technology. We flow-sorted chromosome 5M(g) from a wheat/Aegilops geniculata disomic substitution line [DS5M(g) (5D)] and sequenced it using an Illumina HiSeq 2000 system at approximately 50 × coverage. Paired-end sequences were assembled and used for structural and functional annotation. A total of 4236 genes were annotated on 5M(g) , in close agreement with the predicted number of genes on wheat chromosome 5D (4286). Single-gene FISH indicated no major chromosomal rearrangements between chromosomes 5M(g) and 5D. Comparing chromosome 5M(g) with model grass genomes identified synteny blocks in Brachypodium distachyon, rice (Oryza sativa), sorghum (Sorghum bicolor) and barley (Hordeum vulgare). Chromosome 5M(g) -specific SNPs and cytogenetic probe-based resources were developed and validated. Deletion bin-mapped and ordered 5M(g) SNP markers will be useful to track 5M-specific introgressions and translocations. This study provides a detailed sequence-based analysis of the composition of a chromosome from a distant wild relative of bread wheat, and opens up opportunities to develop genomic resources for wild germplasm to facilitate crop improvement. PMID:26408103

  5. Association, characterisation and meta-analysis of SNPs linked to general reading ability in a German dyslexia case-control cohort.

    Science.gov (United States)

    Müller, Bent; Wilcke, Arndt; Czepezauer, Ivonne; Ahnert, Peter; Boltze, Johannes; Kirsten, Holger

    2016-01-01

    Dyslexia is a severe disorder in the acquisition of reading and writing. Several studies investigated the role of genetics for reading, writing and spelling ability in the general population. However, many of the identified SNPs were not analysed in case-control cohorts. Here, we investigated SNPs previously linked to reading or spelling ability in the general population in a German case-control cohort. Furthermore, we characterised these SNPs for functional relevance with in silico methods and meta-analysed them with previous studies. A total of 16 SNPs within five genes were included. The total number of risk alleles was higher in cases than in controls. Three SNPs were nominally associated with dyslexia: rs7765678 within DCDC2, and rs2038137 and rs6935076 within KIAA0319. The relevance of rs2038137 and rs6935076 was further supported by the meta-analysis. Functional profiling included analysis of tissue-specific expression, annotations for regulatory elements and effects on gene expression levels (eQTLs). Thereby, we found molecular mechanistical implications for 13 of all 16 included SNPs. SNPs associated in our cohort showed stronger gene-specific eQTL effects than non-associated SNPs. In summary, our results validate SNPs previously linked to reading and spelling in the general population in dyslexics and provide insights into their putative molecular pathomechanisms. PMID:27312598

  6. A large-scale rheumatoid arthritis genetic study identifies association at chromosome 9q33.2.

    Directory of Open Access Journals (Sweden)

    Monica Chang

    2008-06-01

    Full Text Available Rheumatoid arthritis (RA is a chronic, systemic autoimmune disease affecting both joints and extra-articular tissues. Although some genetic risk factors for RA are well-established, most notably HLA-DRB1 and PTPN22, these markers do not fully account for the observed heritability. To identify additional susceptibility loci, we carried out a multi-tiered, case-control association study, genotyping 25,966 putative functional SNPs in 475 white North American RA patients and 475 matched controls. Significant markers were genotyped in two additional, independent, white case-control sample sets (661 cases/1322 controls from North America and 596 cases/705 controls from The Netherlands identifying a SNP, rs1953126, on chromosome 9q33.2 that was significantly associated with RA (OR(common = 1.28, trend P(comb = 1.45E-06. Through a comprehensive fine-scale-mapping SNP-selection procedure, 137 additional SNPs in a 668 kb region from MEGF9 to STOM on 9q33.2 were chosen for follow-up genotyping in a staged-approach. Significant single marker results (P(comb 5.41E-09. The observed association patterns for these SNPs had heightened statistical significance and a higher degree of consistency across sample sets. In addition, the allele frequencies for these SNPs displayed reduced variability between control groups when compared to other SNPs. Lastly, in combination with the other two known genetic risk factors, HLA-DRB1 and PTPN22, the variants reported here generate more than a 45-fold RA-risk differential.

  7. Retrospective dosimetry using chromosome painting

    International Nuclear Information System (INIS)

    Chromosome aberration frequency measured in peripheral lymphocytes of persons exposed to ionizing radiation has been used since 1960s for dose assessment. Suspected overexposure is usually evaluated by the frequency of dicentrics and centric rings using an appropriate in vitro calibration curve. However, these chromosome aberrations are unstable with time after exposure and dose reconstruction may encounter uncertainties when the time between the exposure and the analysis is considerable or even unknown. It appears that translocations persist with time after exposure and may be used as an indication of acute past overexposures. Moreover, they appear to accumulate the cytogenetical information, which correlates with the dose received under fractionated, chronic or even occupational exposure conditions. Translocations may be detected using G-banding, which allows to score the total amount of radiation induced translocations but it is a time consuming method, or by Chromosome Painting, a method base on the Fluorescence in situ Hybridization (FISH) technique, painting only some chromosome pairs with specific whole chromosome probes and then extrapolating the observed translocation frequencies to the full genome. The latter method allows a faster aberration scoring than G-banding and appears to be the most promissory tool for biodosimetry, particularly when it is necessary to assess low doses and consequently to score a large number of metaphases, e.g. radiation workers exposed within dose limits. As with the unstable chromosome aberration, it is necessary an in vitro calibration curve based on the frequency of stable chromosome aberrations to assess doses. Our laboratory performed calibration curves for Co60 γ-rays based on the frequencies of unstable (dicentrics and centric rings detected by conventional Giemsa staining) and stable chromosome aberrations (translocations and inversions, detected by G-banding). In order to minimize the interlaboratory variability, we

  8. The Reduction of Chromosome Number in Meiosis Is Determined by Properties Built into the Chromosomes

    OpenAIRE

    Paliulis, Leocadia V.; Nicklas, R. Bruce

    2000-01-01

    In meiosis I, two chromatids move to each spindle pole. Then, in meiosis II, the two are distributed, one to each future gamete. This requires that meiosis I chromosomes attach to the spindle differently than meiosis II chromosomes and that they regulate chromosome cohesion differently. We investigated whether the information that dictates the division type of the chromosome comes from the whole cell, the spindle, or the chromosome itself. Also, we determined when chromosomes can switch from ...

  9. Susceptibility to oral cancers with CD95 and CD95L promoter SNPs may vary with the site and gender.

    Science.gov (United States)

    Daripally, Sarika; Nallapalle, Sateesh Reddy; Katta, Saritha; Prasad, Vidudala V T S

    2015-09-01

    We investigated risk association of oral cancers (tongue and buccal mucosa cancers) with FAS (-1377G > A and FAS -670 A > G) and FASL (-844 T > C) SNPs, in males and females. A case-control study of 535 oral cancer and 525 control subjects was performed. SNPs were detected in the genomic DNA isolated from peripheral blood using PCR-RFLP. We report FASL -844 T > C SNPs increased risk for buccal mucosa cancer in females but not in males. On the other hand, FAS genotypes did not alter the risk of the cancers in both females and males. However, co-occurrence of FAS -1377 GA and -670 GG, FAS -1377 AA and -670 GG genotypes, and combined genotypes of FAS and FASL (FAS -1377 AA + FAS -670 GG + FASL -844 CC) alter male susceptibility towards tongue cancer. In females, combined genotypes of FAS (-1377GA and -670 AA) were found to be a risk factor of buccal mucosa cancer (OR = 3.27, CI = 1.28-8.36; P ≤ 0.01). FASL variants (GA and AA) increased tongue cancer risk in females who were tobacco users compared to non-tobacco users. In conclusion, SNPs of the FAS and FASL might alter risk of tongue and buccal mucosa cancers differentially, in a gender-dependent manner. PMID:25944167

  10. The study of the relation of DNA repair pathway genes SNPs and the sensitivity to radiotherapy and chemotherapy of NSCLC.

    Science.gov (United States)

    Wang, Chunbo; Nie, Huan; Li, Yiqun; Liu, Guiyou; Wang, Xu; Xing, Shijie; Zhang, Liping; Chen, Xin; Chen, Yue; Li, Yu

    2016-01-01

    To analyze the relation between SNPs in DNA repair pathway-related genes and sensitivity of tumor radio-chemotherapy, 26 SNPs in 20 DNA repair genes were genotyped on 176 patients of NSCLC undertaking radio-chemotherapy treatment. In squamous cell carcinoma (SCC), as the rs2228000, rs2228001 (XPC), rs2273953 (TP73), rs2279744 (MDM2), rs2299939 (PTEN) and rs8178085, rs12334811 (DNA-PKcs) affected the sensitivity to chemotherapy, so did the rs8178085, rs12334811 to radiotherapy. Moreover rs344781, rs2273953 and rs12334811 were related with the survival time of SCC. In general, the "good" genotype GG (rs12334811) showed greater efficacy of radio-chemotherapy and MSF (24 months) on SCC. In adenocarcinoma, as the rs2699887 (PIK3), rs12334811 (DNA-PKcs) influenced the sensitivity to chemotherapy, so did the rs2299939, rs2735343 (PTEN) to radiotherapy. And rs402710, rs80270, rs2279744 and rs2909430 impacted the survival time of the adenocarcinoma patients. Both GG (rs2279744) and AG (rs2909430) showed a shorter survival time (MFS = 6). Additionally, some SNPs such as rs2228000, rs2228001 and rs344781 were found to regulate the expression of DNA repair pathway genes through eQTLs dataset analysis. These results indicate that SNPs in DNA repair pathway genes might regulate the expression and affect the DNA damage repair, and thereby impact the efficacy of radio-chemotherapy and the survival time of NSCLC. PMID:27246533

  11. In silico transcriptional regulation and functional analysis of dengue shock syndrome associated SNPs in PLCE1 and MICB genes.

    Science.gov (United States)

    Taqi, Malik Mumtaz; Waseem, Durdana; Ismatullah, Humaira; Haider, Syed Aleem; Faisal, Muhammad

    2016-05-01

    Single nucleotide polymorphisms (SNPs) in PLCE1 and MICB genes increase risk for the development of dengue shock syndrome (DSS). We used Bioinformatics tools to predict alterations at the transcriptional and posttranslational levels driven by PLCE1 and MICB SNPs associated with DSS. Functional and phenotypic analysis conducted to determine deleterious SNPs and impact of amino acid substitution on the structure and function of proteins identified rs2274223 (H1619R) as deleterious to protein coding as it induces structural change in the C2 domain of PLCε, with the mutant residue more positively charged than the wild-type residue (RMSD score, 1.75 Å). Moreover, rs2274223 condenses the chromatin-repressing PLCε expression in DSS. Briefly, this study presents the impact of a single nucleotide transition at SNPs associated with DSS on differential protein binding patterns with PLCE1 and MICB genes and on protein structure modification and their possible role in the pathogenesis of DSS. PMID:27038471

  12. Adiponectin gene ADIPOQ SNP associations with serum adiponectin in two female populations and effects of SNPs on promoter activity

    NARCIS (Netherlands)

    Kyriakou, Theodosios; Collins, Laura J.; Spencer-Jones, Nicola J.; Malcolm, Claire; Wang, Xiaoling; Snieder, Harold; Swaminathan, Ramasamyiyer; Burling, Keith A.; Hart, Deborah J.; Spector, Tim D.; O'Dell, Sandra D.

    2008-01-01

    Adiponectin is an insulin sensitiser in muscle and liver, and low serum levels characterise obesity and insulin resistance. Eight tagging single nucleotide polymorphisms (tSNPs) in the ADIPOQ gene and promoter were selected, and association with serum adiponectin was tested, in two independent sampl

  13. Identification of SNPs and Their Effects on Swine Growth and Carcass Traits for Porcine IGFBP-3 Gene

    Institute of Scientific and Technical Information of China (English)

    LIU De-wu; ZHANG Hao; WU Zhen-fang; LI Jia-qi; YANG Guan-fu; ZHANG Xi-quan

    2008-01-01

    The insulin-like growth factor binding protein-3 (IGFBP-3) was known as a key factor that regulates the effect of insulinlike growth factors (IGF-1 and IGF-2) on pig growth and development. We first identified 38 single nucleotide polymorphisms (SNPs) from a fragment of the IGFBP-3 gene spanning 1 823 bp using the denaturing high-performance liquid chromatography (DHPLC) method and confirmed them by direct sequencing. Among these SNPs, 36 located in introns and the remaining 2 in the 3 prime untranslated region (3UTR). In addition, 16 PCR-RFLP polymorphisms were identified within these SNPs. Three SNPs were then selected to genotype 272 F2 individuals with PCR-RFLP method and the association of polymorphism with growth and carcass traits were analyzed. The results showed that no significant associations were observed between polymorphisms of A265G and A952G and traits. However, the A2670G significantly related with live body length, loin muscle area, and skin and fat percentage (P<0.05); highly significantly associated with weight of carcass lean and lean percentage (P<0.01).

  14. A Markov blanket-based method for detecting causal SNPs in GWAS

    Directory of Open Access Journals (Sweden)

    Han Bing

    2010-04-01

    Full Text Available Abstract Background Detecting epistatic interactions associated with complex and common diseases can help to improve prevention, diagnosis and treatment of these diseases. With the development of genome-wide association studies (GWAS, designing powerful and robust computational method for identifying epistatic interactions associated with common diseases becomes a great challenge to bioinformatics society, because the study of epistatic interactions often deals with the large size of the genotyped data and the huge amount of combinations of all the possible genetic factors. Most existing computational detection methods are based on the classification capacity of SNP sets, which may fail to identify SNP sets that are strongly associated with the diseases and introduce a lot of false positives. In addition, most methods are not suitable for genome-wide scale studies due to their computational complexity. Results We propose a new Markov Blanket-based method, DASSO-MB (Detection of ASSOciations using Markov Blanket to detect epistatic interactions in case-control GWAS. Markov blanket of a target variable T can completely shield T from all other variables. Thus, we can guarantee that the SNP set detected by DASSO-MB has a strong association with diseases and contains fewest false positives. Furthermore, DASSO-MB uses a heuristic search strategy by calculating the association between variables to avoid the time-consuming training process as in other machine-learning methods. We apply our algorithm to simulated datasets and a real case-control dataset. We compare DASSO-MB to other commonly-used methods and show that our method significantly outperforms other methods and is capable of finding SNPs strongly associated with diseases. Conclusions Our study shows that DASSO-MB can identify a minimal set of causal SNPs associated with diseases, which contains less false positives compared to other existing methods. Given the huge size of genomic dataset

  15. Transcriptome characterization and high throughput SSRs and SNPs discovery in Cucurbita pepo (Cucurbitaceae

    Directory of Open Access Journals (Sweden)

    Nuez Fernando

    2011-02-01

    Full Text Available Abstract Background Cucurbita pepo belongs to the Cucurbitaceae family. The "Zucchini" types rank among the highest-valued vegetables worldwide, and other C. pepo and related Cucurbita spp., are food staples and rich sources of fat and vitamins. A broad range of genomic tools are today available for other cucurbits that have become models for the study of different metabolic processes. However, these tools are still lacking in the Cucurbita genus, thus limiting gene discovery and the process of breeding. Results We report the generation of a total of 512,751 C. pepo EST sequences, using 454 GS FLX Titanium technology. ESTs were obtained from normalized cDNA libraries (root, leaves, and flower tissue prepared using two varieties with contrasting phenotypes for plant, flowering and fruit traits, representing the two C. pepo subspecies: subsp. pepo cv. Zucchini and subsp. ovifera cv Scallop. De novo assembling was performed to generate a collection of 49,610 Cucurbita unigenes (average length of 626 bp that represent the first transcriptome of the species. Over 60% of the unigenes were functionally annotated and assigned to one or more Gene Ontology terms. The distributions of Cucurbita unigenes followed similar tendencies than that reported for Arabidopsis or melon, suggesting that the dataset may represent the whole Cucurbita transcriptome. About 34% unigenes were detected to have known orthologs of Arabidopsis or melon, including genes potentially involved in disease resistance, flowering and fruit quality. Furthermore, a set of 1,882 unigenes with SSR motifs and 9,043 high confidence SNPs between Zucchini and Scallop were identified, of which 3,538 SNPs met criteria for use with high throughput genotyping platforms, and 144 could be detected as CAPS. A set of markers were validated, being 80% of them polymorphic in a set of variable C. pepo and C. moschata accessions. Conclusion We present the first broad survey of gene sequences and allelic

  16. Chromosome segregation in plant meiosis

    Directory of Open Access Journals (Sweden)

    Linda eZamariola

    2014-06-01

    Full Text Available Faithful chromosome segregation in meiosis is essential for ploidy stability over sexual life cycles. In plants, defective chromosome segregation caused by gene mutations or other factors leads to the formation of unbalanced or unreduced gametes creating aneuploid or polyploid progeny, respectively. Accurate segregation requires the coordinated execution of conserved processes occurring throughout the two meiotic cell divisions. Synapsis and recombination ensure the establishment of chiasmata that hold homologous chromosomes together allowing their correct segregation in the first meiotic division, which is also tightly regulated by cell-cycle dependent release of cohesin and monopolar attachment of sister kinetochores to microtubules. In meiosis II, bi-orientation of sister kinetochores and proper spindle orientation correctly segregate chromosomes in four haploid cells. Checkpoint mechanisms acting at kinetochores control the accuracy of kinetochore-microtubule attachment, thus ensuring the completion of segregation. Here we review the current knowledge on the processes taking place during chromosome segregation in plant meiosis, focusing on the characterization of the molecular factors involved.

  17. Radiation-induced chromosomal instability

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, S. [GSI, Biophysics, Darmstadt (Germany)

    1999-03-01

    Recent studies on radiation-induced chromosomal instability in the progeny of exposed mammalian cells were briefly described as well as other related studies. For the analysis of chromosomal damage in clones, cells were seeded directly after exposure in cell well-dish to form single cell clones and post-irradiation chromosome aberrations were scored. Both exposure to isoeffective doses of X-ray or 270 MeV/u C-ions (13 keV/{mu}m) increased the number of clones with abnormal karyotype and the increase was similar for X-ray and for C-ions. Meanwhile, in the progeny of cells for mass cultures, there was no indication of a delayed expression of chromosomal damage up to 40 population doublings after the exposure. A high number of aberrant cells were only observed directly after exposure to 10.7 MeV/u O-ions, i.e. in the first cycle cells and decreased with subsequent cell divisions. The reason for these differences in the radiation-induced chromosomal instability between clonal isolates and mass culture has not been clarified. Recent studies indicated that genomic instability occurs at a high frequency in the progeny of cells irradiated with both sparsely and densely ionizing radiation. Such genomic instability is thought likely to increase the risk of carcinogenesis, but more data are required for a well understanding of the health risks resulting from radiation-induced delayed instability. (M.N.)

  18. Dean flow fractionation of chromosomes

    Science.gov (United States)

    Hockin, Matt; Sant, Himanshu J.; Capecchi, Mario; Gale, Bruce K.

    2016-03-01

    Efforts to transfer intact mammalian chromosomes between cells have been attempted for more than 50 years with the consistent result being transfer of sub unit length pieces regardless of method. Inertial microfluidics is a new field that has shown much promise in addressing the fractionation of particles in the 2-20 μm size range (with unknown limits) and separations are based upon particles being carried by curving confined flows (within a spiral shaped, often rectangular flow chamber) and migrating to stable "equilibrium" positions of varying distance from a chamber wall depending on the balance of dean and lift forces. We fabricated spiral channels for inertial microfluidic separations using a standard soft lithography process. The concentration of chromosomes, small contaminant DNA and large cell debris in each outlets were evaluated using microscope (60X) and a flow cytometer. Using Dean Flow Fractionation, we were able to focus 4.5 times more chromosomes in outlet 2 compared to outlet 4 where most of the large debris is found. We recover 16% of the chromosomes in outlet #1- 50% in 2, 23% in 3 and 11% in 4. It should be noted that these estimates of recovery do not capture one piece of information- it actually may be that the chromosomes at each outlet are physically different and work needs to be done to verify this potential.

  19. Chromosomal rearrangement interferes with meiotic X chromosome inactivation

    Czech Academy of Sciences Publication Activity Database

    Homolka, David; Ivánek, Robert; Čapková, Jana; Jansa, Petr; Forejt, Jiří

    2007-01-01

    Roč. 17, č. 10 (2007), s. 1431-1437. ISSN 1088-9051 R&D Projects: GA MŠk(CZ) 1M0520; GA ČR GA301/06/1334; GA ČR GA301/07/1383 Grant ostatní: Howard Hughes Medical Institute(US) HHMI 55000306 Institutional research plan: CEZ:AV0Z50520514 Keywords : chromosomal translocations * meiotic X chromosome inactivation * spermatogenesis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 11.224, year: 2007

  20. WASP: a Web-based Allele-Specific PCR assay designing tool for detecting SNPs and mutations

    Directory of Open Access Journals (Sweden)

    Assawamakin Anunchai

    2007-08-01

    Full Text Available Abstract Background Allele-specific (AS Polymerase Chain Reaction is a convenient and inexpensive method for genotyping Single Nucleotide Polymorphisms (SNPs and mutations. It is applied in many recent studies including population genetics, molecular genetics and pharmacogenomics. Using known AS primer design tools to create primers leads to cumbersome process to inexperience users since information about SNP/mutation must be acquired from public databases prior to the design. Furthermore, most of these tools do not offer the mismatch enhancement to designed primers. The available web applications do not provide user-friendly graphical input interface and intuitive visualization of their primer results. Results This work presents a web-based AS primer design application called WASP. This tool can efficiently design AS primers for human SNPs as well as mutations. To assist scientists with collecting necessary information about target polymorphisms, this tool provides a local SNP database containing over 10 million SNPs of various populations from public domain databases, namely NCBI dbSNP, HapMap and JSNP respectively. This database is tightly integrated with the tool so that users can perform the design for existing SNPs without going off the site. To guarantee specificity of AS primers, the proposed system incorporates a primer specificity enhancement technique widely used in experiment protocol. In particular, WASP makes use of different destabilizing effects by introducing one deliberate 'mismatch' at the penultimate (second to last of the 3'-end base of AS primers to improve the resulting AS primers. Furthermore, WASP offers graphical user interface through scalable vector graphic (SVG draw that allow users to select SNPs and graphically visualize designed primers and their conditions. Conclusion WASP offers a tool for designing AS primers for both SNPs and mutations. By integrating the database for known SNPs (using gene ID or rs number

  1. Functional nsSNPs from carcinogenesis-related genes expressed in breast tissue: Potential breast cancer risk alleles and their distribution across human populations

    Directory of Open Access Journals (Sweden)

    Savas Sevtap

    2006-03-01

    Full Text Available Abstract Although highly penetrant alleles of BRCA1 and BRCA2 have been shown to predispose to breast cancer, the majority of breast cancer cases are assumed to result from the presence of low-moderate penetrant alleles and environmental carcinogens. Non-synonymous single nucleotide polymorphisms (nsSNPs are hypothesised to contribute to disease susceptibility and approximately 30 per cent of them are predicted to have a biological significance. In this study, we have applied a bioinformatics-based strategy to identify breast cancer-related nsSNPs from 981 carcinogenesis-related genes expressed in breast tissue. Our results revealed a total of 367 validated nsSNPs, 109 (29.7 per cent of which are predicted to affect the protein function (functional nsSNPs, suggesting that these nsSNPs are likely to influence the development and homeostasis of breast tissue and hence contribute to breast cancer susceptibility. Sixty-seven of the functional nsSNPs presented as commonly occurring nsSNPs (minor allele frequencies ≥ 5 per cent, representing excellent candidates for breast cancer susceptibility. Additionally, a non-uniform distribution of the common functional nsSNPs among different human populations was observed: 15 nsSNPs were reported to be present in all populations analysed, whereas another set of 15 nsSNPs was specific to particular population(s. We propose that the nsSNPs analysed in this study constitute a unique resource of potential genetic factors for breast cancer susceptibility. Furthermore, the variations in functional nsSNP allele frequencies across major population backgrounds may point to the potential variability of the molecular basis of breast cancer predisposition and treatment response among different human populations.

  2. Escape Artists of the X Chromosome.

    Science.gov (United States)

    Balaton, Bradley P; Brown, Carolyn J

    2016-06-01

    Inactivation of one X chromosome in mammalian females achieves dosage compensation between XX females and XY males; however, over 15% of human X-linked genes continue to be expressed from the inactive X chromosome. New genomic methodologies have improved our identification and characterization of these escape genes, revealing the importance of DNA sequence, chromatin structure, and chromosome ultrastructure in regulating expression from an otherwise inactive chromosome. Study of these exceptions to the rule of silencing highlights the interconnectedness of chromatin and chromosome structure in X-chromosome inactivation (XCI). Recent advances also demonstrate the importance of these genes in sexually dimorphic disease risk, particularly cancer. PMID:27103486

  3. SNPs in transporter and metabolizing genes as predictive markers for oxaliplatin treatment in colorectal cancer patients.

    Science.gov (United States)

    Kap, Elisabeth J; Seibold, Petra; Scherer, Dominique; Habermann, Nina; Balavarca, Yesilda; Jansen, Lina; Zucknick, Manuela; Becker, Natalia; Hoffmeister, Michael; Ulrich, Alexis; Benner, Axel; Ulrich, Cornelia M; Burwinkel, Barbara; Brenner, Hermann; Chang-Claude, Jenny

    2016-06-15

    Oxaliplatin is frequently used as part of a chemotherapeutic regimen with 5-fluorouracil in the treatment of colorectal cancer (CRC). The cellular availability of oxaliplatin is dependent on metabolic and transporter enzymes. Variants in genes encoding these enzymes may cause variation in response to oxaliplatin and could be potential predictive markers. Therefore, we used a two-step procedure to comprehensively investigate 1,444 single nucleotide polymorphisms (SNPs) from these pathways for their potential as predictive markers for oxaliplatin treatment, using 623 stage II-IV CRC patients (of whom 201 patients received oxaliplatin) from a German prospective patient cohort treated with adjuvant or palliative chemotherapy. First, all genes were screened using the global test that evaluated SNP*oxaliplatin interaction terms per gene. Second, one model was created by backward elimination on all SNP*oxaliplatin interactions of the selected genes. The statistical procedure was evaluated using bootstrap analyses. Nine genes differentially associated with overall survival according to oxaliplatin treatment (unadjusted p values analysis we show an improvement of the prediction error of 3.7% in patients treated with oxaliplatin. Several variants in genes involved in metabolism and transport could thus be potential predictive markers for oxaliplatin treatment in CRC patients. If confirmed, inclusion of these variants in a predictive test could identify patients who are more likely to benefit from treatment with oxaliplatin. PMID:26835885

  4. Au-nanoprobes for detection of SNPs associated with antibiotic resistance in Mycobacterium tuberculosis

    International Nuclear Information System (INIS)

    Tuberculosis (TB) is one of the leading causes of infection in humans, causing high morbility and mortality all over the world. The rate of new cases of multidrug resistant tuberculosis (MDRTB) continues to increase, and since these infections are very difficult to manage, they constitute a serious health problem. In most cases, drug resistance in Mycobacterium tuberculosis has been related to mutations in several loci within the pathogen's genome. The development of fast, cheap and simple screening methodologies would be of paramount relevance for the early detection of these mutations, essential for the timely and effective diagnosis and management of MDRTB patients. The use of gold nanoparticles derivatized with thiol-modified oligonucleotides (Au-nanoprobes) has led to new approaches in molecular diagnostics. Based on the differential non-cross-linking aggregation of Au-nanoprobes, we were able to develop a colorimetric method for the detection of specific sequences and to apply this approach to pathogen identification and single base mutations/single nucleotide polymorphisms (SNP) discrimination. Here we report on the development of Au-nanoprobes for the specific identification of SNPs within the beta subunit of the RNA polymerase (rpoB locus), responsible for resistance to rifampicin in over 95% of rifampicin resistant M. tuberculosis strains.

  5. Adults with Chromosome 18 Abnormalities.

    Science.gov (United States)

    Soileau, Bridgette; Hasi, Minire; Sebold, Courtney; Hill, Annice; O'Donnell, Louise; Hale, Daniel E; Cody, Jannine D

    2015-08-01

    The identification of an underlying chromosome abnormality frequently marks the endpoint of a diagnostic odyssey. However, families are frequently left with more questions than answers as they consider their child's future. In the case of rare chromosome conditions, a lack of longitudinal data often makes it difficult to provide anticipatory guidance to these families. The objective of this study is to describe the lifespan, educational attainment, living situation, and behavioral phenotype of adults with chromosome 18 abnormalities. The Chromosome 18 Clinical Research Center has enrolled 483 individuals with one of the following conditions: 18q-, 18p-, Tetrasomy 18p, and Ring 18. As a part of the ongoing longitudinal study, we collect data on living arrangements, educational level attained, and employment status as well as data on executive functioning and behavioral skills on an annual basis. Within our cohort, 28 of the 483 participants have died, the majority of whom have deletions encompassing the TCF4 gene or who have unbalanced rearrangement involving other chromosomes. Data regarding the cause of and age at death are presented. We also report on the living situation, educational attainment, and behavioral phenotype of the 151 participants over the age of 18. In general, educational level is higher for people with all these conditions than implied by the early literature, including some that received post-high school education. In addition, some individuals are able to live independently, though at this point they represent a minority of patients. Data on executive function and behavioral phenotype are also presented. Taken together, these data provide insight into the long-term outcome for individuals with a chromosome 18 condition. This information is critical in counseling families on the range of potential outcomes for their child. PMID:25403900

  6. Making chromosome abnormalities treatable conditions.

    Science.gov (United States)

    Cody, Jannine DeMars; Hale, Daniel Esten

    2015-09-01

    Individuals affected by the classic chromosome deletion syndromes which were first identified at the beginning of the genetic age, are now positioned to benefit from genomic advances. This issue highlights five of these conditions (4p-, 5p-, 11q-, 18p-, and 18q-). It focuses on the increased in understanding of the molecular underpinnings and envisions how these can be transformed into effective treatments. While it is scientifically exciting to see the phenotypic manifestations of hemizygosity being increasingly understood at the molecular and cellular level, it is even more amazing to consider that we are now on the road to making chromosome abnormalities treatable conditions. PMID:26351122

  7. Using Chromosomes to Teach Evolution: Chromosomal Rearrangements in Speciation Events.

    Science.gov (United States)

    Offner, Susan

    1994-01-01

    Uses diagrams to aid in discussing how the English map of the human chromosomes, published by Offner in 1993, can be used to illustrate some important questions in evolution, as well as give students a glimpse into some of the mechanisms underlying evolutionary change. (ZWH)

  8. Identification of QTLs for eight agronomically important traits using an ultra-high-density map based on SNPs generated from high-throughput sequencing in sorghum under contrasting photoperiods.

    Science.gov (United States)

    Zou, Guihua; Zhai, Guowei; Feng, Qi; Yan, Song; Wang, Ahong; Zhao, Qiang; Shao, Jianfeng; Zhang, Zhipeng; Zou, Jianqiu; Han, Bin; Tao, Yuezhi

    2012-09-01

    The productivity of sorghum is mainly determined by agronomically important traits. The genetic bases of these traits have historically been dissected and analysed through quantitative trait locus (QTL) mapping based on linkage maps with low-throughput molecular markers, which is one of the factors that hinder precise and complete information about the numbers and locations of the genes or QTLs controlling the traits. In this study, an ultra-high-density linkage map based on high-quality single nucleotide polymorphisms (SNPs) generated from low-coverage sequences (~0.07 genome sequence) in a sorghum recombinant inbred line (RIL) population was constructed through new sequencing technology. This map consisted of 3418 bin markers and spanned 1591.4 cM of genome size with an average distance of 0.5 cM between adjacent bins. QTL analysis was performed and a total of 57 major QTLs were detected for eight agronomically important traits under two contrasting photoperiods. The phenotypic variation explained by individual QTLs varied from 3.40% to 33.82%. The high accuracy and quality of this map was evidenced by the finding that genes underlying two cloned QTLs, Dw3 for plant height (chromosome 7) and Ma1 for flowering time (chromosome 6), were localized to the correct genomic regions. The close associations between two genomic regions on chromosomes 6 and 7 with multiple traits suggested the existence of pleiotropy or tight linkage. Several major QTLs for heading date, plant height, numbers of nodes, stem diameter, panicle neck length, and flag leaf width were detected consistently under both photoperiods, providing useful information for understanding the genetic mechanisms of the agronomically important traits responsible for the change of photoperiod. PMID:22859680

  9. Cacao single-nucleotide polymorphism (SNP) markers: A discovery strategy to identify SNPs for genotyping, genetic mapping and genome wide association studies (GWAS)

    Science.gov (United States)

    Single-nucleotide polymorphisms (SNPs) are the most common genetic markers in Theobroma cacao, occurring approximately once in every 200 nucleotides. SNPs, like microsatellites, are co-dominant and PCR-based, but they have several advantages over microsatellites. They are unambiguous, so that a SN...

  10. Characterization of chromosome structures of Falconinae (Falconidae, Falconiformes, Aves) by chromosome painting and delineation of chromosome rearrangements during their differentiation

    OpenAIRE

    Nishida, Chizuko; Ishijima, Junko; KOSAKA, Ayumi; Tanabe, Hideyuki; Habermann, Felix A.; Griffin, Darren K.; MATSHUDA, Yoichi; 秀之, 田辺

    2008-01-01

    Karyotypes of most bird species are characterized by around 2n = 80 chromosomes, comprising 7–10 pairs of large- and medium-sized macrochromosomes including sex chromosomes and numerous morphologically indistinguishable microchromosomes. The Falconinae of the Falconiformes has a different karyotype from the typical avian karyotype in low chromosome numbers, little size difference between macrochromosomes and a smaller number of microchromosomes. To characterize chromosome structures of Falcon...

  11. Characterization of chromosome structures of Falconinae (Falconidae, Falconiformes, Aves) by chromosome painting and delineation of chromosome rearrangements during their differentiation

    OpenAIRE

    Nishida, Chizuko; Ishijima, Junko; KOSAKA, Ayumi; Tanabe, Hideyuki; Habermann, Felix A.; Griffin, Darren K.; Matsuda, Yoichi

    2008-01-01

    Karyotypes of most bird species are characterized by around 2n = 80 chromosomes, comprising 7Y10 pairs of large- and medium-sized macrochromosomes including sex chromosomes and numerous morphologically indistinguishable microchromosomes. The Falconinae of the Falconiformes has a different karyotype from the typical avian karyotype in low chromosome numbers, little size difference between macrochromosomes and a smaller number of microchromosomes. To characterize chromosome structures of Falcon...

  12. Radiation induced chromosomal instability in lymphocytes of cancer patients

    International Nuclear Information System (INIS)

    Full text: Cytokinesis-blocked micronucleus (CBMN) assay has been extensively used to evaluate the radiation sensitivity of human individuals. Using the CBMN assay, Scott et al (1998, 1999) demonstrated that a fraction of radiosensitive individuals in breast cancer case population was larger than in normal individual population. However, Vral et al were very skeptical about the Scott et al's findings (2002). Under the approval from the ethical committee of NIRS, peripheral blood was obtained from 46 normal healthy females, 131 breast cancer patients, 32 cervical cancer patients and 7 female head and neck cancer patients. Radiosensitivity of T-lymphocytes was assessed by using a CBMN assay. The frequencies of MN per binucleated cell in healthy donors were 0.031(±0.010) and 0.151(±0.066) for cells treated before and after X-ray-irradiation (2Gy), respectively. Spontaneous MN frequencies in cancer patients were significantly higher than healthy donors (p < 0.001). Radiation sensitivities of breast- and head and neck-cancer patients were significantly higher than normal individuals (p < 0.001). Cervical cancer patients were more resistant to irradiation than healthy donors, though the number of cases for statistical analysis was small. (p < 0.001). We are considering that the HPV infection affected the radiosensitivity of cervical cancer cases. Because it is widely believed that one key mechanism which leads to spontaneous micronucleus formation involves an imbalance of chromosomal segregation and a chromosomal instability in patients' lymphocytes might be greater than that in normal individuals' lymphocytes. Recently, Kuschel et al (2002) demonstrated that ratios in two SNPs on XRCC3 were significantly different between cancer patients and healthy females. Then, we can suppose that the radiation-related genes with low penetrance may be involved in tumorigenesis of mammary- and head and neck-cells, and also, in patients' radiation susceptibility

  13. Identificação de SNPs para conteúdo de ácidos graxos em soja pela técnica HRM

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Antunes da Cruz

    2013-12-01

    Full Text Available O objetivo deste trabalho foi identificar SNPs em genes associados ao conteúdo de ácidos graxos em soja e implementar a metodologia "high resolution melting" (HRM para genotipagem desses SNPs. Os iniciadores HRM foram desenhados para discriminar os alelos SNPs em duas populações de mapeamento (RILs e F2 e seguiram o padrão esperado de segregação. Os SNPs do gene ABI associaram-se significativamente ao conteúdo de ácido esteárico (R² = 12,14, e os do gene FAD3B, aos conteúdos de ácido oleico (R² = 14,69 e linolênico (R² = 10,62. A técnica de genotipagem dos SNPs por HRM é eficiente na discriminação das classes genotípicas.

  14. Design of a High Density SNP Genotyping Assay in the Pig Using SNPs Identified and Characterized by Next Generation Sequencing Technology

    DEFF Research Database (Denmark)

    Ramos, Antonio M; Crooijmans, Richard P M A; Nabeel, Nabeel A;

    2009-01-01

    Background The dissection of complex traits of economic importance to the pig industry requires the availability of a significant number of genetic markers, such as single nucleotide polymorphisms (SNPs). This study was conducted to discover several hundreds of thousands of porcine SNPs using next...... generation sequencing technologies and use these SNPs, as well as others from different public sources, to design a high-density SNP genotyping assay. Methodology/Principal Findings A total of 19 reduced representation libraries derived from four swine breeds (Duroc, Landrace, Large White, Pietrain) and a...... Wild Boar population and three restriction enzymes (AluI, HaeIII and MspI) were sequenced using Illumina's Genome Analyzer (GA). The SNP discovery effort resulted in the de novo identification of over 372K SNPs. More than 549K SNPs were used to design the Illumina Porcine 60K+SNP iSelect Beadchip, now...

  15. Mathematical glimpse on the Y chromosome degeneration

    Science.gov (United States)

    Lobo, M. P.

    2006-04-01

    The Y chromosomes are genetically degenerate and do not recombine with their matching partners X. Non-recombination of XY pairs has been pointed out as the key factor for the degeneration of the Y chromosome. The aim here is to show that there is a mathematical asymmetry in sex chromosomes which leads to the degeneration of Y chromosomes even in the absence of XX and XY recombination. A model for sex-chromosome evolution in a stationary regime is proposed. The consequences of their asymmetry are analyzed and lead us to a couple of conclusions. First, Y chromosome degeneration shows up sqrt{2} more often than X chromosome degeneration. Second, if nature prohibits female mortalities from beeing exactly 50%, then Y chromosome degeneration is inevitable.

  16. CHROMOSOMAL MULTIPLICITY IN BURKHOLDERIA CEPACIA

    Science.gov (United States)

    We have used CHEF gel electrophoresis to screen preparations of large DNA from different Burkholderia cepacia isolates for the presence of DNA species corresponding to the linearized forms of the three chromosomes of 3.4,2.5, and 0.9 Mb identified in B. cepacia strain 17616. DNA ...

  17. Vibrio chromosome-specific families

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Ussery, David

    2014-01-01

    We have compared chromosome-specific genes in a set of 18 finished Vibrio genomes, and, in addition, also calculated the pan- and core-genomes from a data set of more than 250 draft Vibrio genome sequences. These genomes come from 9 known species and 2 unknown species. Within the finished...

  18. Chromosome Territory Modeller and Viewer.

    Science.gov (United States)

    Tkacz, Magdalena A; Chromiński, Kornel; Idziak-Helmcke, Dominika; Robaszkiewicz, Ewa; Hasterok, Robert

    2016-01-01

    This paper presents ChroTeMo, a tool for chromosome territory modelling, accompanied by ChroTeVi-a chromosome territory visualisation software that uses the data obtained by ChroTeMo. These tools have been developed in order to complement the molecular cytogenetic research of interphase nucleus structure in a model grass Brachypodium distachyon. Although the modelling tool has been initially created for one particular species, it has universal application. The proposed version of ChroTeMo allows for generating a model of chromosome territory distribution in any given plant or animal species after setting the initial, species-specific parameters. ChroTeMo has been developed as a fully probabilistic modeller. Due to this feature, the comparison between the experimental data on the structure of a nucleus and the results obtained from ChroTeMo can indicate whether the distribution of chromosomes inside a nucleus is also fully probabilistic or is subjected to certain non-random patterns. The presented tools have been written in Python, so they are multiplatform, portable and easy to read. Moreover, if necessary they can be further developed by users writing their portions of code. The source code, documentation, and wiki, as well as the issue tracker and the list of related articles that use ChroTeMo and ChroTeVi, are accessible in a public repository at Github under GPL 3.0 license. PMID:27505434

  19. Chromosome Territory Modeller and Viewer

    Science.gov (United States)

    Idziak-Helmcke, Dominika; Robaszkiewicz, Ewa; Hasterok, Robert

    2016-01-01

    This paper presents ChroTeMo, a tool for chromosome territory modelling, accompanied by ChroTeVi–a chromosome territory visualisation software that uses the data obtained by ChroTeMo. These tools have been developed in order to complement the molecular cytogenetic research of interphase nucleus structure in a model grass Brachypodium distachyon. Although the modelling tool has been initially created for one particular species, it has universal application. The proposed version of ChroTeMo allows for generating a model of chromosome territory distribution in any given plant or animal species after setting the initial, species-specific parameters. ChroTeMo has been developed as a fully probabilistic modeller. Due to this feature, the comparison between the experimental data on the structure of a nucleus and the results obtained from ChroTeMo can indicate whether the distribution of chromosomes inside a nucleus is also fully probabilistic or is subjected to certain non-random patterns. The presented tools have been written in Python, so they are multiplatform, portable and easy to read. Moreover, if necessary they can be further developed by users writing their portions of code. The source code, documentation, and wiki, as well as the issue tracker and the list of related articles that use ChroTeMo and ChroTeVi, are accessible in a public repository at Github under GPL 3.0 license. PMID:27505434

  20. SNPs in the coding region of the metastasis-inducing gene MACC1 and clinical outcome in colorectal cancer

    Directory of Open Access Journals (Sweden)

    Schmid Felicitas

    2012-07-01

    Full Text Available Abstract Background Colorectal cancer is one of the main cancers in the Western world. About 90% of the deaths arise from formation of distant metastasis. The expression of the newly identified gene metastasis associated in colon cancer 1 (MACC1 is a prognostic indicator for colon cancer metastasis. Here, we analyzed for the first time the impact of single nucleotide polymorphisms (SNPs in the coding region of MACC1 for clinical outcome of colorectal cancer patients. Additionally, we screened met proto-oncogene (Met, the transcriptional target gene of MACC1, for mutations. Methods We sequenced the coding exons of MACC1 in 154 colorectal tumors (stages I, II and III and the crucial exons of Met in 60 colorectal tumors (stages I, II and III. We analyzed the association of MACC1 polymorphisms with clinical data, including metachronous metastasis, UICC stages, tumor invasion, lymph node metastasis and patients’ survival (n = 154, stages I, II and III. Furthermore, we performed biological assays in order to evaluate the functional impact of MACC1 SNPs on the motility of colorectal cancer cells. Results We genotyped three MACC1 SNPs in the coding region. Thirteen % of the tumors had the genotype cg (rs4721888, L31V, 48% a ct genotype (rs975263, S515L and 84% a gc or cc genotype (rs3735615, R804T. We found no association of these SNPs with clinicopathological parameters or with patients’ survival, when analyzing the entire patients’ cohort. An increased risk for a shorter metastasis-free survival of patients with a ct genotype (rs975263 was observed in younger colon cancer patients with stage I or II (P = 0.041, n = 18. In cell culture, MACC1 SNPs did not affect MACC1-induced cell motility and proliferation. Conclusion In summary, the identification of coding MACC1 SNPs in primary colorectal tumors does not improve the prediction for metastasis formation or for patients’ survival compared to MACC1 expression analysis alone. The ct genotype (rs

  1. Y-chromosome diversity in Catalan surname samples: insights into surname origin and frequency.

    Science.gov (United States)

    Solé-Morata, Neus; Bertranpetit, Jaume; Comas, David; Calafell, Francesc

    2015-11-01

    The biological behavior of the Y chromosome, which is paternally inherited, implies that males sharing the same surname may also share a similar Y chromosome. However, socio-cultural factors, such as polyphyletism, non-paternity, adoption, or matrilineal surname transmission, may prevent the joint transmission of the surname and the Y chromosome. By genotyping 17 Y-STRs and 68 SNPs in ~2500 male samples that each carried one of the 50 selected Catalan surnames, we could determine sets of descendants of a common ancestor, the population of origin of the common ancestor, and the date when such a common ancestor lived. Haplotype diversity was positively correlated with surname frequency, that is, rarer surnames showed the strongest signals of coancestry. Introgression rates of Y chromosomes into a surname by non-paternity, adoption, and transmission of the maternal surname were estimated at 1.5-2.6% per generation, with some local variation. Average ages for the founders of the surnames were estimated at ~500 years, suggesting a delay between the origin of surnames (twelfth and thirteenth centuries) and the systematization of their paternal transmission. We have found that, in general, a foreign etymology for a surname does not often result in a non-indigenous origin of surname founders; however, bearers of some surnames with an Arabic etymology show an excess of North African haplotypes. Finally, we estimate that surname prediction from a Y-chromosome haplotype, which may have interesting forensic applications, has a ~60% sensitivity but a 17% false discovery rate. PMID:25689924

  2. An X chromosome association scan of the Norfolk Island genetic isolate provides evidence for a novel migraine susceptibility locus at Xq12.

    Directory of Open Access Journals (Sweden)

    Bridget H Maher

    Full Text Available Migraine is a common and debilitating neurovascular disorder with a complex envirogenomic aetiology. Numerous studies have demonstrated a preponderance of women affected with migraine and previous pedigree linkage studies in our laboratory have identified susceptibility loci on chromosome Xq24-Xq28. In this study we have used the genetic isolate of Norfolk Island to further analyse the X chromosome for migraine susceptibility loci.An association approach was employed to analyse 14,124 SNPs spanning the entire X chromosome. Genotype data from 288 individuals comprising a large core-pedigree, of which 76 were affected with migraine, were analysed. Although no SNP reached chromosome-wide significance (empirical α = 1 × 10(-5 ranking by P-value revealed two primary clusters of SNPs in the top 25. A 10 SNP cluster represents a novel migraine susceptibility locus at Xq12 whilst a 11 SNP cluster represents a previously identified migraine susceptibility locus at Xq27. The strongest association at Xq12 was seen for rs599958 (OR = 1.75, P = 8.92 × 10(-4, whilst at Xq27 the strongest association was for rs6525667 (OR = 1.53, P = 1.65 × 10(-4. Further analysis of SNPs at these loci was performed in 5,122 migraineurs from the Women's Genome Health Study and provided additional evidence for association at the novel Xq12 locus (P<0.05.Overall, this study provides evidence for a novel migraine susceptibility locus on Xq12. The strongest effect SNP (rs102834, joint P = 1.63 × 10(-5 is located within the 5'UTR of the HEPH gene, which is involved in iron homeostasis in the brain and may represent a novel pathway for involvement in migraine pathogenesis.

  3. Multicolor spectral karyotyping of human chromosomes.

    Science.gov (United States)

    Schröck, E; du Manoir, S; Veldman, T; Schoell, B; Wienberg, J; Ferguson-Smith, M A; Ning, Y; Ledbetter, D H; Bar-Am, I; Soenksen, D; Garini, Y; Ried, T

    1996-07-26

    The simultaneous and unequivocal discernment of all human chromosomes in different colors would be of significant clinical and biologic importance. Whole-genome scanning by spectral karyotyping allowed instantaneous visualization of defined emission spectra for each human chromosome after fluorescence in situ hybridization. By means of computer separation (classification) of spectra, spectrally overlapping chromosome-specific DNA probes could be resolved, and all human chromosomes were simultaneously identified. PMID:8662537

  4. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH SPERM DISORDERS

    OpenAIRE

    L. Y. Pylyp; L. A. Spinenko; V. D. Zukin; N. M. Bilko

    2013-01-01

    Chromosomal abnormalities are among the most common genetic causes of spermatogenic disruptions. Carriers of chromosomal abnormalities are at increased risk of infertility, miscarriage or birth of a child with unbalanced karyotype due to the production of unbalanced gametes. The natural selection against chromosomally abnormal sperm usually prevents fertilization with sperm barring in cases of serious chromosomal abnormalities. However, assisted reproductive technologies in general and intrac...

  5. Association study of candidate genes for susceptibility to schizophrenia and bipolar disorder on chromosome 22Q13

    DEFF Research Database (Denmark)

    Severinsen, Jacob; Binderup, Helle; Mors, Ole; Wang, August G; Vang, Maria; Murray, V; Muir, Walter; Mckee, I; Kruse, Torben A; Blackwood, Douglas HR; Ewald, Henrik; Børglum, Anders

    Chromosome 22q is suspected to harbor risk genes for schizophrenia as well as bipolar affective disorder. This is evidenced through genetic mapping studies, investigations of cytogenetic abnormalities, and direct examination of candidate genes. In a recent study of distantly related patients from...... the Faroe Islands we have obtained evidence suggesting two regions on chromosome 22q13 to potentially harbor susceptibility genes for both schizophrenia and bipolar affective disorder. We have selected a number of candidate genes from these two regions for further analysis, including the neuro......-gene WKL1, in which a missense mutation recently has been suggested to cause catatonic schizophrenia in a German family. The selected candidate genes were analyzed by a combination of database search and direct sequencing in a subset of the patients from the Faroe Islands in order to identify SNPs in the...

  6. Evolution of sex chromosomes ZW of Schistosoma mansoni inferred from chromosome paint and BAC mapping analyses.

    Science.gov (United States)

    Hirai, Hirohisa; Hirai, Yuriko; LoVerde, Philip T

    2012-12-01

    Chromosomes of schistosome parasites among digenetic flukes have a unique evolution because they exhibit the sex chromosomes ZW, which are not found in the other groups of flukes that are hermaphrodites. We conducted molecular cytogenetic analyses for investigating the sex chromosome evolution using chromosome paint analysis and BAC clones mapping. To carry this out, we developed a technique for making paint probes of genomic DNA from a single scraped chromosome segment using a chromosome microdissection system, and a FISH mapping technique for BAC clones. Paint probes clearly identified each of the 8 pairs of chromosomes by a different fluorochrome color. Combination analysis of chromosome paint analysis with Z/W probes and chromosome mapping with 93 BAC clones revealed that the W chromosome of Schistosoma mansoni has evolved by at least four inversion events and heterochromatinization. Nine of 93 BAC clones hybridized with both the Z and W chromosomes, but the locations were different between Z and W chromosomes. The homologous regions were estimated to have moved from the original Z chromosome to the differentiated W chromosome by three inversions events that occurred before W heterohcromatinization. An inversion that was observed in the heterochromatic region of the W chromosome likely occurred after W heterochromatinization. These inversions and heterochromatinization are hypothesized to be the key factors that promoted the evolution of the W chromosome of S. mansoni. PMID:22831897

  7. Temperature Switch PCR (TSP: Robust assay design for reliable amplification and genotyping of SNPs

    Directory of Open Access Journals (Sweden)

    Mather Diane E

    2009-12-01

    Full Text Available Abstract Background Many research and diagnostic applications rely upon the assay of individual single nucleotide polymorphisms (SNPs. Thus, methods to improve the speed and efficiency for single-marker SNP genotyping are highly desirable. Here, we describe the method of temperature-switch PCR (TSP, a biphasic four-primer PCR system with a universal primer design that permits amplification of the target locus in the first phase of thermal cycling before switching to the detection of the alleles. TSP can simplify assay design for a range of commonly used single-marker SNP genotyping methods, and reduce the requirement for individual assay optimization and operator expertise in the deployment of SNP assays. Results We demonstrate the utility of TSP for the rapid construction of robust and convenient endpoint SNP genotyping assays based on allele-specific PCR and high resolution melt analysis by generating a total of 11,232 data points. The TSP assays were performed under standardised reaction conditions, requiring minimal optimization of individual assays. High genotyping accuracy was verified by 100% concordance of TSP genotypes in a blinded study with an independent genotyping method. Conclusion Theoretically, TSP can be directly incorporated into the design of assays for most current single-marker SNP genotyping methods. TSP provides several technological advances for single-marker SNP genotyping including simplified assay design and development, increased assay specificity and genotyping accuracy, and opportunities for assay automation. By reducing the requirement for operator expertise, TSP provides opportunities to deploy a wider range of single-marker SNP genotyping methods in the laboratory. TSP has broad applications and can be deployed in any animal and plant species.

  8. Chromosome Aberrations by Heavy Ions

    Science.gov (United States)

    Ballarini, Francesca; Ottolenghi, Andrea

    It is well known that mammalian cells exposed to ionizing radiation can show different types of chromosome aberrations (CAs) including dicentrics, translocations, rings, deletions and complex exchanges. Chromosome aberrations are a particularly relevant endpoint in radiobiology, because they play a fundamental role in the pathways leading either to cell death, or to cell conversion to malignancy. In particular, reciprocal translocations involving pairs of specific genes are strongly correlated (and probably also causally-related) with specific tumour types; a typical example is the BCR-ABL translocation for Chronic Myeloid Leukaemia. Furthermore, aberrations can be used for applications in biodosimetry and more generally as biomarkers of exposure and risk, that is the case for cancer patients monitored during Carbon-ion therapy and astronauts exposed to space radiation. Indeed hadron therapy and astronauts' exposure to space radiation represent two of the few scenarios where human beings can be exposed to heavy ions. After a brief introduction on the main general features of chromosome aberrations, in this work we will address key aspects of the current knowledge on chromosome aberration induction, both from an experimental and from a theoretical point of view. More specifically, in vitro data will be summarized and discussed, outlining important issues such as the role of interphase death/mitotic delay and that of complex-exchange scoring. Some available in vivo data on cancer patients and astronauts will be also reported, together with possible interpretation problems. Finally, two of the few available models of chromosome aberration induction by ionizing radiation (including heavy ions) will be described and compared, focusing on the different assumptions adopted by the authors and on how these models can deal with heavy ions.

  9. A case of trisomy of chromosome 15

    OpenAIRE

    Coldwell, S; Fitzgerald, B.; Semmens, J.M.; Ede, R; Bateman, C

    1981-01-01

    We describe a case of trisomy of chromosome 15 in an infant who presented at birth with numerous abnormalities. As far as we are aware this chromosomal abnormality has not been described before. On the basis of this one case there appear to be no features which are specific to this chromosomal abnormality.

  10. Analysis and visualization of chromosomal abnormalities in SNP data with SNPscan

    Directory of Open Access Journals (Sweden)

    Thomas George H

    2006-01-01

    Full Text Available Abstract Background A variety of diseases are caused by chromosomal abnormalities such as aneuploidies (having an abnormal number of chromosomes, microdeletions, microduplications, and uniparental disomy. High density single nucleotide polymorphism (SNP microarrays provide information on chromosomal copy number changes, as well as genotype (heterozygosity and homozygosity. SNP array studies generate multiple types of data for each SNP site, some with more than 100,000 SNPs represented on each array. The identification of different classes of anomalies within SNP data has been challenging. Results We have developed SNPscan, a web-accessible tool to analyze and visualize high density SNP data. It enables researchers (1 to visually and quantitatively assess the quality of user-generated SNP data relative to a benchmark data set derived from a control population, (2 to display SNP intensity and allelic call data in order to detect chromosomal copy number anomalies (duplications and deletions, (3 to display uniparental isodisomy based on loss of heterozygosity (LOH across genomic regions, (4 to compare paired samples (e.g. tumor and normal, and (5 to generate a file type for viewing SNP data in the University of California, Santa Cruz (UCSC Human Genome Browser. SNPscan accepts data exported from Affymetrix Copy Number Analysis Tool as its input. We validated SNPscan using data generated from patients with known deletions, duplications, and uniparental disomy. We also inspected previously generated SNP data from 90 apparently normal individuals from the Centre d'Étude du Polymorphisme Humain (CEPH collection, and identified three cases of uniparental isodisomy, four females having an apparently mosaic X chromosome, two mislabelled SNP data sets, and one microdeletion on chromosome 2 with mosaicism from an apparently normal female. These previously unrecognized abnormalities were all detected using SNPscan. The microdeletion was independently

  11. A genome-wide association study reveals a quantitative trait locus for days open on chromosome 2 in Japanese Black cattle.

    Science.gov (United States)

    Sasaki, Shinji; Ibi, Takayuki; Kojima, Takatoshi; Sugimoto, Yoshikazu

    2016-02-01

    Days open (DO), which is the interval from calving to conception, is an important trait related to reproductive performance in cattle. To identify quantitative trait loci for DO in Japanese Black cattle, we conducted a genome-wide association study with 33,303 single nucleotide polymorphisms (SNPs) using 459 animals with extreme DO values selected from a larger group of 15,488 animals. We identified a SNP on bovine chromosome 2 (BTA2) that was associated with DO. After imputation using phased haplotype data inferred from 586 812 SNPs of 1041 Japanese Black cattle, six SNPs associated with DO were located in an 8.5-kb region of high linkage disequilibrium on BTA2. These SNPs were located on the telomeric side at a distance of 177 kb from the parathyroid hormone 2 receptor (PTH2R) gene. The association was replicated in a sample of 1778 animals. In the replicated population, the frequency of the reduced-DO allele (Q) was 0.63, and it accounted for 1.72% of the total genetic variance. The effect of a Q-to-q allele substitution on DO was a decrease of 3.74 days. The results suggest that the Q allele could serve as a marker in Japanese Black cattle to select animals with superior DO performance. PMID:26374166

  12. Association between the European GWAS-Identified Susceptibility Locus at Chromosome 4p16 and the Risk of Atrial Septal Defect: A Case-Control Study in Southwest China and a Meta-Analysis

    OpenAIRE

    Zhao, Li; Li, Bei; Dian, Ke; Ying, Binwu; Lu, Xiaojun; Hu, Xuejiao; An, Qi; CHEN, CHUNXIA; Huang, Chunyan; Tan, Bin; Qin, Li

    2015-01-01

    Atrial septal defect (ASD) is the third most frequent type of congenital heart anomaly, featuring shunting of blood between the two atria. Gene-environment interaction remains to be an acknowledged cause for ASD occurrence. A recent European genome-wide association study (GWAS) of congenital heart disease (CHD) identified 3 susceptibility SNPs at chromosome 4p16 associated with ASD: rs870142, rs16835979 and rs6824295. A Chinese-GWAS of CHD conducted in the corresponding period did not reveal ...

  13. Forensic typing of autosomal SNPs with a 29 SNP-multiplex--results of a collaborative EDNAP exercise

    DEFF Research Database (Denmark)

    Sanchez, Juan Jose; Børsting, C; Balogh, K;

    2008-01-01

    We report the results of an inter-laboratory exercise on typing of autosomal single nucleotide polymorphisms (SNP) for forensic genetic investigations in crime cases. The European DNA Profiling Group (EDNAP), a working group under the International Society for Forensic Genetics (ISFG), organised...... the exercise. A total of 11 European and one US forensic genetic laboratories tested a subset of a 52 SNP-multiplex PCR kit developed by the SNPforID consortium. The 52 SNP-multiplex kit amplifies 52 DNA fragments with 52 autosomal SNP loci in one multiplex PCR. The 52 SNPs are detected in two...... separate single base extension (SBE) multiplex reactions with 29 and 23 SNPs, respectively, using SNaPshot kit, capillary electrophoresis and multicolour fluorescence detection. For practical reasons, only the 29 SBE multiplex reaction was carried out by the participating laboratories. A total of 11...

  14. Chromosomal instability in Streptomyces avermitilis: major deletion in the central region and stable circularized chromosome

    Directory of Open Access Journals (Sweden)

    Wen Ying

    2010-07-01

    Full Text Available Abstract Background The chromosome of Streptomyces has been shown to be unstable, frequently undergoing gross chromosomal rearrangements. However, the mechanisms underlying this phenomenon remain unclear, with previous studies focused on two chromosomal ends as targets for rearrangements. Here we investigated chromosomal instability of Streptomyces avermitilis, an important producer of avermectins, and characterized four gross chromosomal rearrangement events, including a major deletion in the central region. The present findings provide a valuable contribution to the mechanistic study of genetic instability in Streptomyces. Results Thirty randomly-selected "bald" mutants derived from the wild-type strain all contained gross chromosomal rearrangements of various types. One of the bald mutants, SA1-8, had the same linear chromosomal structure as the high avermectin-producing mutant 76-9. Chromosomes of both strains displayed at least three independent chromosomal rearrangements, including chromosomal arm replacement to form new 88-kb terminal inverted repeats (TIRs, and two major deletions. One of the deletions eliminated the 36-kb central region of the chromosome, but surprisingly did not affect viability of the cells. The other deletion (74-kb was internal to the right chromosomal arm. The chromosome of another bald mutant, SA1-6, was circularized with deletions at both ends. No obvious homology was found in all fusion sequences. Generational stability analysis showed that the chromosomal structure of SA1-8 and SA1-6 was stable. Conclusions Various chromosomal rearrangements, including chromosomal arm replacement, interstitial deletions and chromosomal circularization, occurred in S. avermitilis by non-homologous recombination. The finding of an inner deletion involving in the central region of S. avermitilis chromosome suggests that the entire Streptomyces chromosome may be the target for rearrangements, which are not limited, as previously

  15. The origin of human chromosome 2 analyzed by comparative chromosome mapping with a DNA microlibrary

    OpenAIRE

    Wienberg, Johannes; Jauch, Anna; Lüdecke, H J; Senger, G; Horsthemke, B; Claussen, U; Cremer, Thomas; Arnold, N.; Lengauer, Christoph

    1994-01-01

    Fluorescencein situ hybridization (FISH) of microlibraries established from distinct chromosome subregions can test the evolutionary conservation of chromosome bands as well as chromosomal rearrangements that occurred during primate evolution and will help to clarify phylogenetic relationships. We used a DNA library established by microdissection and microcloning from the entire long arm of human chromosome 2 for fluorescencein situ hybridization and comparative mapping of the chromosomes of ...

  16. Mapping and linkage disequilibrium analysis with a genome-wide collection of SNPs that detect polymorphism in cultivated tomato

    OpenAIRE

    Robbins, Matthew D.; Sim, Sung-Chur; Yang, Wencai; Van Deynze, Allen; Van der Knaap, Esther; Joobeur, Tarek; Francis, David M.

    2010-01-01

    The history of tomato (Solanum lycopersicum L.) improvement includes genetic bottlenecks, wild species introgressions, and divergence into distinct market classes. This history makes tomato an excellent model to investigate the effects of selection on genome variation. A combination of linkage mapping in two F2 populations and physical mapping with emerging genome sequence data was used to position 434 PCR-based markers including SNPs. Three-hundred-and-forty markers were used to genotype 102...

  17. Detection of associations with rare and common SNPs for quantitative traits: a nonparametric Bayes-based approach

    OpenAIRE

    Ding Lili; Baye Tesfaye M; He Hua; Zhang Xue; Kurowski Brad G; Martin Lisa J

    2011-01-01

    Abstract We propose a nonparametric Bayes-based clustering algorithm to detect associations with rare and common single-nucleotide polymorphisms (SNPs) for quantitative traits. Unlike current methods, our approach identifies associations with rare genetic variants at the variant level, not the gene level. In this method, we use a Dirichlet process prior for the distribution of SNP-specific regression coefficients, conduct hierarchical clustering with a distance measure derived from posterior ...

  18. GLIDERS - A web-based search engine for genome-wide linkage disequilibrium between HapMap SNPs

    Directory of Open Access Journals (Sweden)

    Broxholme John

    2009-10-01

    Full Text Available Abstract Background A number of tools for the examination of linkage disequilibrium (LD patterns between nearby alleles exist, but none are available for quickly and easily investigating LD at longer ranges (>500 kb. We have developed a web-based query tool (GLIDERS: Genome-wide LInkage DisEquilibrium Repository and Search engine that enables the retrieval of pairwise associations with r2 ≥ 0.3 across the human genome for any SNP genotyped within HapMap phase 2 and 3, regardless of distance between the markers. Description GLIDERS is an easy to use web tool that only requires the user to enter rs numbers of SNPs they want to retrieve genome-wide LD for (both nearby and long-range. The intuitive web interface handles both manual entry of SNP IDs as well as allowing users to upload files of SNP IDs. The user can limit the resulting inter SNP associations with easy to use menu options. These include MAF limit (5-45%, distance limits between SNPs (minimum and maximum, r2 (0.3 to 1, HapMap population sample (CEU, YRI and JPT+CHB combined and HapMap build/release. All resulting genome-wide inter-SNP associations are displayed on a single output page, which has a link to a downloadable tab delimited text file. Conclusion GLIDERS is a quick and easy way to retrieve genome-wide inter-SNP associations and to explore LD patterns for any number of SNPs of interest. GLIDERS can be useful in identifying SNPs with long-range LD. This can highlight mis-mapping or other potential association signal localisation problems.

  19. The prevalence of unique SNPs in the renin-angiotensin system highlights the need for pharmacogenetics in Indigenous Australians.

    Science.gov (United States)

    Grimson, Steven; Cox, Amanda J; Pringle, Kirsty G; Burns, Christine; Lumbers, Eugenie R; Blackwell, C Caroline; Scott, Rodney J

    2016-02-01

    Genetic differences between ethnic populations affect susceptibility to disease and efficacy of drugs. This study examined and compared the prevalence of single nucleotide polymorphisms (SNPs) in genes of the renin-angiotensin system (RAS) in a desert community of Indigenous Australians and in non-Indigenous Australians. The polymorphisms were angiotensinogen, AGT G-217A (rs5049); AGT G+174A (rs4762); Angiotensin II type 1 receptor, AGTR1 A+1166C (rs5186); angiotensin converting enzyme, ACE A-240T (rs4291), ACE T-93C (rs4292); renin, REN T+1142C (rs5706). They were measured using allelic discrimination assays. The prevalence of REN T+1142C SNP was similar in the two populations; 99% were homozygous for the T allele. All other SNPs were differently distributed between the two populations (P < 0.0001). In non-Indigenous Australians, the A allele at position 204 of ACE rs4291 was prevalent (61.8%) whereas in the Indigenous Australians the A allele was less prevalent (28%). For rs4292, the C allele had a prevalence of 37.9% in non-Indigenous Australians but in Indigenous Australians the prevalence was only 1%. No Indigenous individuals were homozygous for the C allele of AGTR1 (rs5186). Thus the prevalence of RAS SNPs in this Indigenous Australian desert community was different from non-Indigenous Australians as was the prevalence of cytokine SNPs (as shown in a previous study). These differences may affect susceptibility to chronic renal and cardiovascular disease and may alter the efficacy of drugs used to inhibit the RAS. These studies highlight the need to study the pharmacogenetics of drug absorption, distribution, metabolism and excretion in Indigenous Australians for safe prescribing guidelines. PMID:26667052

  20. LRRK2 gene G2019S mutation and SNPs [haplotypes] in subtypes of Parkinson’s disease

    Science.gov (United States)

    Patra, Biswanath; Parsian, Azemat J.; Racette, Brad A.; Zhao, Jing Hua; Perlmutter, Joel S.; Parsian, Abbas

    2009-01-01

    Mutation within the Leucine-rich repeat kinase 2 (LRRK2) gene has been identified as a cause of autosomal dominant Parkinson’s disease (PD). The purpose of this study was to determine the frequency of G2019S mutation and whether the differences in the allele and genotype distribution of six SNPs within LRRK2 gene are associated with PD in an American non-Hispanic white population. The sample included 350 sporadic PD (SPD), 225 familial PD (FPD) patients and 186 controls of the same race and ethnicity. The frequency of LRRK2 G2019S mutation in our total sample of PD (FPD and SPD) was 1.56%. The frequency of this mutation was 3.5% in the FPD and 0.3% in the SPD groups, respectively. Allele and genotype frequencies of six SNPs were compared between PD and control samples. In addition, PD groups were categorized by sporadic PD (no family history), familial PD (first degree relative with PD) and age of onset (AON, ≤50 or ≥51 years). The haplotypes of the six SNPs were also constructed for association analysis. After correction for multiple comparisons, there was no association between any SNPs (allele or genotype) and PD groups. One of the haplotypes was modestly associated with the combined PD (SPD & FPD) sample. There was also no association with age at onset of PD. Our study suggests that the LRRK2 gene may be a risk factor or the cause for a very small fraction of PD in American white population. PMID:18752982

  1. Signatures of selection in the Iberian honey bee: a genome wide approach using single nucleotide polymorphisms (SNPs)

    OpenAIRE

    Chavez-Galarza, Julio; Johnston, J. Spencer; Azevedo, João; Muñoz, Irene; De La Rúa, Pilar; Patton, John C.; Pinto, M. Alice

    2011-01-01

    Dissecting genome-wide (expansions, contractions, admixture) from genome-specific effects (selection) is a goal of central importance in evolutionary biology because it leads to more robust inferences of demographic history and to identification of adaptive divergence. The publication of the honey bee genome and the development of high-density SNPs genotyping, provide us with powerful tools, allowing us to identify signatures of selection in the honey bee genome. These signatures will be an i...

  2. Characterization of genome-wide SNPs for the water flea Daphnia pulicaria generated by genotyping-by-sequencing (GBS)

    Science.gov (United States)

    Muñoz, Joaquín; Chaturvedi, Anurag; De Meester, Luc; Weider, Lawrence J.

    2016-01-01

    The keystone aquatic herbivore Daphnia has been studied for more than 150 years in the context of evolution, ecology and ecotoxicology. Although it is rapidly becoming an emergent model for environmental and population genomics, there have been limited genome-wide level studies in natural populations. We report a unique resource of novel Single Nucleotide Polymorphic (SNP) markers for Daphnia pulicaria using the reduction in genomic complexity with the restriction enzymes approach, genotyping-by-sequencing. Using the genome of D. pulex as a reference, SNPs were scored for 53 clones from five natural populations that varied in lake trophic status. Our analyses resulted in 32,313 highly confident and bi-allelic SNP markers. 1,364 outlier SNPs were mapped on the annotated D. pulex genome, which identified 2,335 genes, including 565 within functional genes. Out of 885 EuKaryotic Orthologous Groups that we found from outlier SNPs, 294 were involved in three metabolic and four regulatory pathways. Bayesian-clustering analyses showed two distinct population clusters representing the possible combined effects of geography and lake trophic status. Our results provide an invaluable tool for future population genomics surveys in Daphnia targeting informative regions related to physiological processes that can be linked to the ecology of this emerging eco-responsive taxon. PMID:27346179

  3. SNPs in DNA repair or oxidative stress genes and late subcutaneous fibrosis in patients following single shot partial breast irradiation

    Directory of Open Access Journals (Sweden)

    Falvo Elisabetta

    2012-01-01

    Full Text Available Abstract Background The aim of this study was to evaluate the potential association between single nucleotide polymorphisms related response to radiotherapy injury, such as genes related to DNA repair or enzymes involved in anti-oxidative activities. The paper aims to identify marker genes able to predict an increased risk of late toxicity studying our group of patients who underwent a Single Shot 3D-CRT PBI (SSPBI after BCS (breast conserving surgery. Methods A total of 57 breast cancer patients who underwent SSPBI were genotyped for SNPs (single nucleotide polymorphisms in XRCC1, XRCC3, GST and RAD51 by Pyrosequencing technology. Univariate analysis (ORs and 95% CI was performed to correlate SNPs with the risk of developing ≥ G2 fibrosis or fat necrosis. Results A higher significant risk of developing ≥ G2 fibrosis or fat necrosis in patients with: polymorphic variant GSTP1 (Ile105Val (OR = 2.9; 95%CI, 0.88-10.14, p = 0.047. Conclusions The presence of some SNPs involved in DNA repair or response to oxidative stress seem to be able to predict late toxicity. Trial Registration ClinicalTrials.gov: NCT01316328

  4. The Effects of Sequence Variation on Genome-wide NRF2 Binding—New Target Genes and Regulatory SNPs

    Science.gov (United States)

    Kuosmanen, Suvi M.; Viitala, Sari; Laitinen, Tuomo; Peräkylä, Mikael; Pölönen, Petri; Kansanen, Emilia; Leinonen, Hanna; Raju, Suresh; Wienecke-Baldacchino, Anke; Närvänen, Ale; Poso, Antti; Heinäniemi, Merja; Heikkinen, Sami; Levonen, Anna-Liisa

    2016-01-01

    Transcription factor binding specificity is crucial for proper target gene regulation. Motif discovery algorithms identify the main features of the binding patterns, but the accuracy on the lower affinity sites is often poor. Nuclear factor E2-related factor 2 (NRF2) is a ubiquitous redox-activated transcription factor having a key protective role against endogenous and exogenous oxidant and electrophile stress. Herein, we decipher the effects of sequence variation on the DNA binding sequence of NRF2, in order to identify both genome-wide binding sites for NRF2 and disease-associated regulatory SNPs (rSNPs) with drastic effects on NRF2 binding. Interactions between NRF2 and DNA were studied using molecular modelling, and NRF2 chromatin immunoprecipitation-sequence datasets together with protein binding microarray measurements were utilized to study binding sequence variation in detail. The binding model thus generated was used to identify genome-wide binding sites for NRF2, and genomic binding sites with rSNPs that have strong effects on NRF2 binding and reside on active regulatory elements in human cells. As a proof of concept, miR-126–3p and -5p were identified as NRF2 target microRNAs, and a rSNP (rs113067944) residing on NRF2 target gene (Ferritin, light polypeptide, FTL) promoter was experimentally verified to decrease NRF2 binding and result in decreased transcriptional activity. PMID:26826707

  5. Influence of Gender and SNPs in GPX1 Gene on Biomarkers of Selenium Status in Healthy Brazilians

    Science.gov (United States)

    Donadio, Janaina L. S.; Guerra-Shinohara, Elvira M.; Rogero, Marcelo M.; Cozzolino, Silvia M. F.

    2016-01-01

    Selenium (Se) status varies worldwide as a result of natural variation of Se content in soils, dietary pattern, and the presence of SNPs. Further, Se status in Brazilians and its relationship between genetic variation and Se biomarkers is unknown. This work investigated the association between SNPs in glutathione peroxidase genes and biomarkers of Se status in healthy Brazilians. The study was conducted in 116 healthy adults in São Paulo, Brazil. Plasma and erythrocyte Se were measured by HGFAAS. Erythrocyte GPx (eGPx) activity was measured spectrometrically in a biochemical analyzer. Genotypes were determined by real-time PCR using Taqman® Assays. eGPx activity was higher in females compared with males. Lower erythrocyte Se concentrations were found in heterozygous GC carriers for GPX1 rs8179169. eGPx activity was higher in females with the common genotypes, except for rs8179169. GC carriers for rs8179169 had lower erythrocyte Se in both genders, and only male carriers of the variant alleles of both rs1050450 and rs1800668 had higher eGPx activity. In conclusion, the genotype for SNPs in GPX1 and gender affected biomarkers of Se status in this pilot study with healthy Brazilians. PMID:27164132

  6. Temporal genomic evolution of bird sex chromosomes

    DEFF Research Database (Denmark)

    Wang, Zongji; Zhang, Jilin; Yang, Wei;

    2014-01-01

    driving forces of Z chromosome evolution, we analyze here 45 newly available bird genomes and four species' transcriptomes, over their course of recombination loss between the sex chromosomes. RESULTS: We show Z chromosomes in general have a significantly higher substitution rate in introns and synonymous...... evolved very recently. CONCLUSIONS: In conclusion, we uncover that the sequence and expression patterns of Z chromosome genes covary with their ages of becoming Z-linked. In contrast to the mammalian X chromosomes, such patterns are mainly driven by mutational bias and genetic drift in birds, due...... to the opposite sex-biased inheritance of Z vs. X....

  7. Holoprosencephaly due to numeric chromosome abnormalities.

    Science.gov (United States)

    Solomon, Benjamin D; Rosenbaum, Kenneth N; Meck, Jeanne M; Muenke, Maximilian

    2010-02-15

    Holoprosencephaly (HPE) is the most common malformation of the human forebrain. When a clinician identifies a patient with HPE, a routine chromosome analysis is often the first genetic test sent for laboratory analysis in order to assess for a structural or numerical chromosome anomaly. An abnormality of chromosome number is overall the most frequently identified etiology in a patient with HPE. These abnormalities include trisomy 13, trisomy 18, and triploidy, though several others have been reported. Such chromosome number abnormalities are almost universally fatal early in gestation or in infancy. Clinical features of specific chromosome number abnormalities may be recognized by phenotypic manifestations in addition to the HPE. PMID:20104610

  8. Novel insights into mitotic chromosome condensation

    Science.gov (United States)

    Piskadlo, Ewa; Oliveira, Raquel A.

    2016-01-01

    The fidelity of mitosis is essential for life, and successful completion of this process relies on drastic changes in chromosome organization at the onset of nuclear division. The mechanisms that govern chromosome compaction at every cell division cycle are still far from full comprehension, yet recent studies provide novel insights into this problem, challenging classical views on mitotic chromosome assembly. Here, we briefly introduce various models for chromosome assembly and known factors involved in the condensation process (e.g. condensin complexes and topoisomerase II). We will then focus on a few selected studies that have recently brought novel insights into the mysterious way chromosomes are condensed during nuclear division.

  9. Transient Microgeographic Clines during B Chromosome Invasion.

    Science.gov (United States)

    Camacho, Juan Pedro M; Shaw, Michael W; Cabrero, Josefa; Bakkali, Mohammed; Ruíz-Estévez, Mercedes; Ruíz-Ruano, Francisco J; Martín-Blázquez, Rubén; López-León, María Dolores

    2015-11-01

    The near-neutral model of B chromosome evolution predicts that the invasion of a new population should last some tens of generations, but the details on how it proceeds in real populations are mostly unknown. Trying to fill this gap, we analyze here a natural population of the grasshopper Eyprepocnemis plorans at three time points during the last 35 years. Our results show that B chromosome frequency increased significantly during this period and that a cline observed in 1992 had disappeared in 2012 once B chromosome frequency reached an upper limit at all sites sampled. This indicates that, during B chromosome invasion, transient clines for B chromosome frequency are formed at the invasion front on a microgeographic scale. Computer simulation experiments showed that the pattern of change observed for genotypic frequencies is consistent with the existence of B chromosome drive through females and selection against individuals with a high number of B chromosomes. PMID:26655780

  10. Mitosis. Microtubule detyrosination guides chromosomes during mitosis.

    Science.gov (United States)

    Barisic, Marin; Silva e Sousa, Ricardo; Tripathy, Suvranta K; Magiera, Maria M; Zaytsev, Anatoly V; Pereira, Ana L; Janke, Carsten; Grishchuk, Ekaterina L; Maiato, Helder

    2015-05-15

    Before chromosomes segregate into daughter cells, they align at the mitotic spindle equator, a process known as chromosome congression. Centromere-associated protein E (CENP-E)/Kinesin-7 is a microtubule plus-end-directed kinetochore motor required for congression of pole-proximal chromosomes. Because the plus-ends of many astral microtubules in the spindle point to the cell cortex, it remains unknown how CENP-E guides pole-proximal chromosomes specifically toward the equator. We found that congression of pole-proximal chromosomes depended on specific posttranslational detyrosination of spindle microtubules that point to the equator. In vitro reconstitution experiments demonstrated that CENP-E-dependent transport was strongly enhanced on detyrosinated microtubules. Blocking tubulin tyrosination in cells caused ubiquitous detyrosination of spindle microtubules, and CENP-E transported chromosomes away from spindle poles in random directions. Thus, CENP-E-driven chromosome congression is guided by microtubule detyrosination. PMID:25908662

  11. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH RECURRENT MISCARRIAGE

    Directory of Open Access Journals (Sweden)

    Daniela Mierla

    2012-06-01

    Full Text Available Chromosomal abnormalities are involved in the etiology of recurrent spontaneous pregnancy loss and sub-fertility. The purpose of this study was to determine the frequency and contribution of chromosomal abnormalities in recurrent miscarriages. The results obtained and literature review are helpful in understanding the importance of cytogenetics analysis of female infertility. To investigate the distribution of chromosomal abnormalities in the Romanian population with recurrent miscarriage, karyotype analysis by G-banding was performed from peripheral blood in 967 women infertility. Results: Chromosomal abnormalities were found to 79 women (8,17%. The percentage of chromosomal abnormalities in the studied population correlates with the data in the literature. Chromosomal abnormalities could play the important role in etiology of infertility and are more frequently detected in this group of patients compared to general population. In the infertile couples balanced chromosomal abnormalities are the main cause of spontaneous abortions.

  12. [The evolution of human Y chromosome].

    Science.gov (United States)

    Yang, Xianrong; Wang, Meiqin; Li, Shaohua

    2014-09-01

    The human Y chromosome is always intriguing for researchers, because of its role in gender determination and its unusual evolutionary history. The Y chromosome evolves from an autosome, and its evolution has been characterized by massive gene decay. The lack of recombination and protein-coding genes and high content of repetitive sequences have hindered the progress in our understanding of the Y chromosome biology. Recently, with the advances in comparative genomics and sequencing technology, the research on Y chromosome has become a hotspot, with an intensified debate about Y-chromosome final destination resulting from degeneration. This review focuses on the structure, inheritance characteristics, gene content, and the origin and evolution of Y chromosome. We also discuss the long-term destiny of Y chromosome. PMID:25252301

  13. Dynamics of chromosome segregation in Escherichia coli

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck

    2007-01-01

    Since the 1960’es the conformation and segregation of the chromosome in Escherichia coli has been a subject of interest for many scientists. However, after 40 years of research, we still know incredibly little about how the chromosome is organized inside the cell, how it manages to duplicate this...... and reliable method enabled us to start the analysis on the distribution of various chromosomal loci inside slowly growing cells. With the actual counting and measuring no longer being any problem we could easily analyze 14 loci distributed on the E.coli chromosome. More than 15.000 cells were...... on the P1 par system. Using the new system, which is based on the pMT1 par system from Yersenia pestis, we labeled loci on opposite sides of the E.coli chromosome simultaneously and were able to show that the E.coli chromosome is organized with one chromosomal arm in each cell half. This astounding...

  14. Microdissection and chromosome painting of the alien chromosome in an addition line of wheat-Thinopyrum intermedium

    Science.gov (United States)

    The chromosome painting is an efficient tool for chromosome research. However, plant chromosome painting is relatively underdeveloped. In this study, chromosome painting was developed and used to identify alien chromosomes in TAi-27, a wheat-Thinopyrum intermedium addition line, and chromosomes of...

  15. Sequence diversity in three tomato species: SNPs, markers, and molecular evolution

    Directory of Open Access Journals (Sweden)

    Maloof Julin N

    2009-07-01

    new analysis of the extensive tomato EST sequences available that represents the most comprehensive survey of sequence diversity across Solanum species to date. These SNPs, plus thousands of molecular makers designed to detect the polymorphisms are available to the community via a website. Evolutionary analyses on these polymorphism uncovered sets of genes potentially important for the evolution and domestication of tomato; interestingly these sets were enriched for genes involved in response to the environment.

  16. International workshop of chromosome 19

    Energy Technology Data Exchange (ETDEWEB)

    Pericak-Vance, M.A. (Duke Univ. Medical Center, Durham, NC (United States). Div. of Neurology); Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))

    1991-09-16

    This document summarizes the workshop on physical and genetic mapping of chromosome 19. The first session discussed the major disease loci found on the chromosome. The second session concentrated on reference families, markers and linkage maps. The third session concentrated on radiation hybrid mapping, somatic cell hybrid panels, macro restriction maps and YACs, followed by cDNA and long range physical maps. The fourth session concentrated on compiling consensus genetic and physical maps as well as discussing regions of conflict. The final session dealt with the LLNL cosmid contig database and comparative mapping of homologous regions of the human and mouse genomes, and ended with a discussion of resource sharing. 18 refs., 2 figs. (MHB)

  17. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits

    Science.gov (United States)

    Paes, Geísa Pinheiro; Viana, José Marcelo Soriano; Silva, Fabyano Fonseca e; Mundim, Gabriel Borges

    2016-01-01

    Abstract The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D), the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis. PMID:27007903

  18. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits.

    Science.gov (United States)

    Paes, Geísa Pinheiro; Viana, José Marcelo Soriano; Silva, Fabyano Fonseca E; Mundim, Gabriel Borges

    2016-03-01

    The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D), the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis. PMID:27007903

  19. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits

    Directory of Open Access Journals (Sweden)

    Geísa Pinheiro Paes

    2016-03-01

    Full Text Available Abstract The objectives of this study were to assess linkage disequilibrium (LD and selection-induced changes in single nucleotide polymorphism (SNP frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D, the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis.

  20. Baseline chromosome aberrations in children

    Czech Academy of Sciences Publication Activity Database

    Merlo, D.F.; Ceppi, M.; Stagi, E.; Bocchini, V.; Šrám, Radim; Rössner st., Pavel

    2007-01-01

    Roč. 172, - (2007), s. 60-67. ISSN 0378-4274 Grant ostatní: EU(EU) 2002-02198; EU(EU) 2005-016320 Institutional research plan: CEZ:AV0Z50390512 Source of funding: R - rámcový projekt EK ; R - rámcový projekt EK Keywords : chromosome aberrations * children * molecular epidemiology Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.826, year: 2007

  1. Clonality - X Chromosome Inactivation Assay

    OpenAIRE

    sprotocols

    2014-01-01

    Author: Molecular Profiling Initiative, NCI This method was successful in our lab using prostate tissue and for our specific objectives. Investigators must be aware that they will need to tailor the following protocol for their own research objectives and tissue under study. Investigators can utilize X chromosome inactivation (methylation) to determine the clonality status of a tumor or premalignant lesion in females. The technique is based on a methylation-sensitive restriction enzym...

  2. Hobo transposons causing chromosomal breakpoints.

    OpenAIRE

    Ladevèze, V; Aulard, S.; Chaminade, N; Périquet, G; Lemeunier, F

    1998-01-01

    Several laboratory surveys have shown that transposable elements (TEs) can cause chromosomal breaks and lead to inversions, as in dysgenic crosses involving P-elements. However, it is not presently clear what causes inversions in natural populations of Drosophila. The only direct molecular studies must be taken as evidence against the involvement of mobile elements. Here, in Drosophila lines transformed with the hobo transposable element, and followed for 100 generations, we show the appearan...

  3. Chromosomal instability determines taxane response

    OpenAIRE

    Swanton, Charles; Nicke, Barbara; Schuett, Marion; Eklund, Aron C.; Ng, Charlotte; Li, Qiyuan; Hardcastle, Thomas; Lee, Alvin; Roy, Rajat; East, Philip; Kschischo, Maik; Endesfelder, David; Wylie, Paul; Kim, Se Nyun; Chen, Jie-Guang

    2009-01-01

    Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting chromosomal instability (CIN). Silencing 22/50 of these genes, many of which are involved in DNA repair, caused cancer cell death, suggesting that these genes are involved in the survival of aneuploid cells....

  4. Chromosome aberration assays in Allium

    Energy Technology Data Exchange (ETDEWEB)

    Grant, W.F.

    1982-01-01

    The common onion (Allium cepa) is an excellent plant for the assay of chromosome aberrations after chemical treatment. Other species of Allium (A. cepa var. proliferum, A. carinatum, A. fistulosum and A. sativum) have also been used but to a much lesser extent. Protocols have been given for using root tips from either bulbs or seeds of Allium cepa to study the cytological end-points, such as chromosome breaks and exchanges, which follow the testing of chemicals in somatic cells. It is considered that both mitotic and meiotic end-points should be used to a greater extent in assaying the cytogenetic effects of a chemical. From a literature survey, 148 chemicals are tabulated that have been assayed in 164 Allium tests for their clastogenic effect. Of the 164 assays which have been carried out, 75 are reported as giving a positive reaction, 49 positive and with a dose response, 1 positive and temperature-related, 9 borderline positive, and 30 negative; 76% of the chemicals gave a definite positive response. It is proposed that the Allium test be included among those tests routinely used for assessing chromosomal damage induced by chemicals.

  5. Chromosome rearrangements and transposable elements.

    Science.gov (United States)

    Lonnig, Wolf-Ekkehard; Saedler, Heinz

    2002-01-01

    There has been limited corroboration to date for McClintock's vision of gene regulation by transposable elements (TEs), although her proposition on the origin of species by TE-induced complex chromosome reorganizations in combination with gene mutations, i.e., the involvement of both factors in relatively sudden formations of species in many plant and animal genera, has been more promising. Moreover, resolution is in sight for several seemingly contradictory phenomena such as the endless reshuffling of chromosome structures and gene sequences versus synteny and the constancy of living fossils (or stasis in general). Recent wide-ranging investigations have confirmed and enlarged the number of earlier cases of TE target site selection (hot spots for TE integration), implying preestablished rather than accidental chromosome rearrangements for nonhomologous recombination of host DNA. The possibility of a partly predetermined generation of biodiversity and new species is discussed. The views of several leading transposon experts on the rather abrupt origin of new species have not been synthesized into the macroevolutionary theory of the punctuated equilibrium school of paleontology inferred from thoroughly consistent features of the fossil record. PMID:12429698

  6. The origin of Mosuo people as revealed by mtDNA and Y chromosome variation

    Institute of Scientific and Technical Information of China (English)

    WEN; Bo; SHI; Hong; REN; Ling; XI; Huifeng; LI; Kaiyuan; ZHA

    2004-01-01

    The Mosuo, living in the Lugu Lake area in northwest Yunnan Province, China, is the only matriarchal population in China. The Mosuo was officially identified as Naxi nationality although its relationship with Naxi remains controversial. We studied the genetic relationship between the Mosuo and five other ethnic groups currently residing in northwest Yunnan, i.e. Naxi, Tibetan, Bai, Yi and Pumi, by typing the genetic variations in mtDNA HVS1 and 21 Y chromosome markers (13 SNPs & 8 STR markers). We showed that the maternal lineages of the Mosuo bear the strongest resemblance with those found in Naxi while its paternal lineages are more similar to those that are prevalent in Yunnan Tibetan. The marked difference between paternal and maternal lineages may be attributable to the genetic history, matriarchal structure, and visiting marriage.

  7. Comparative analysis of sex chromosomes in Leporinus species (Teleostei, Characiformes) using chromosome painting

    Science.gov (United States)

    2013-01-01

    Background The Leporinus genus, belonging to the Anostomidae family, is an interesting model for studies of sex chromosome evolution in fish, particularly because of the presence of heteromorphic sex chromosomes only in some species of the genus. In this study we used W chromosome-derived probes in a series of cross species chromosome painting experiments to try to understand events of sex chromosome evolution in this family. Results W chromosome painting probes from Leporinus elongatus, L. macrocephalus and L. obtusidens were hybridized to each others chromosomes. The results showed signals along their W chromosomes and the use of L. elongatus W probe against L. macrocephalus and L. obtusidens also showed signals over the Z chromosome. No signals were observed when the later aforementioned probe was used in hybridization procedures against other four Anostomidae species without sex chromosomes. Conclusions Our results demonstrate a common origin of sex chromosomes in L. elongatus, L. macrocephalus and L. obtusidens but suggest that the L. elongatus chromosome system is at a different evolutionary stage. The absence of signals in the species without differentiated sex chromosomes does not exclude the possibility of cryptic sex chromosomes, but they must contain other Leporinus W sequences than those described here. PMID:23822802

  8. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae (Teleostei, Characidae)

    Science.gov (United States)

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko, Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    Abstract B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of Moenkhausia sanctaefilomenae. The results revealed that DNA sequences were shared between a specific B chromosome and many chromosomes of the A complement in all populations analyzed, suggesting a possible intra-specific origin of these B chromosomes. However, no hybridization signals were observed in other B chromosomes found in the same individuals, implying a possible independent origin of B chromosome variants in this species. FISH experiments using 18S rDNA probes revealed the presence of non-active ribosomal genes in some B chromosomes and in some chromosomes of the A complement, suggesting that at least two types of B chromosomes had an independent origin. The role of heterochromatic segments and ribosomal sequences in the origin of B chromosomes were discussed. PMID:26753081

  9. Chromosomal divergence and evolutionary inferences in Rhodniini based on the chromosomal location of ribosomal genes

    Directory of Open Access Journals (Sweden)

    Sebastian Pita

    2013-05-01

    Full Text Available In this study, we used fluorescence in situ hybridisation to determine the chromosomal location of 45S rDNA clusters in 10 species of the tribe Rhodniini (Hemiptera: Reduviidae: Triatominae. The results showed striking inter and intraspecific variability, with the location of the rDNA clusters restricted to sex chromosomes with two patterns: either on one (X chromosome or both sex chromosomes (X and Y chromosomes. This variation occurs within a genus that has an unchanging diploid chromosome number (2n = 22, including 20 autosomes and 2 sex chromosomes and a similar chromosome size and genomic DNA content, reflecting a genome dynamic not revealed by these chromosome traits. The rDNA variation in closely related species and the intraspecific polymorphism in Rhodnius ecuadoriensis suggested that the chromosomal position of rDNA clusters might be a useful marker to identify recently diverged species or populations. We discuss the ancestral position of ribosomal genes in the tribe Rhodniini and the possible mechanisms involved in the variation of the rDNA clusters, including the loss of rDNA loci on the Y chromosome, transposition and ectopic pairing. The last two processes involve chromosomal exchanges between both sex chromosomes, in contrast to the widely accepted idea that the achiasmatic sex chromosomes of Heteroptera do not interchange sequences.

  10. Novel Y-chromosome Short Tandem Repeat Variants Detected Through the Use of Massively Parallel Sequencing

    Institute of Scientific and Technical Information of China (English)

    David H Warshauer; Jennifer D Churchill; Nicole Novroski; Jonathan L King; Bruce Budowle

    2015-01-01

    Massively parallel sequencing (MPS) technology is capable of determining the sizes of short tandem repeat (STR) alleles as well as their individual nucleotide sequences. Thus, single nucleotide polymorphisms (SNPs) within the repeat regions of STRs and variations in the pattern of repeat units in a given repeat motif can be used to differentiate alleles of the same length. In this study, MPS was used to sequence 28 forensically-relevant Y-chromosome STRs in a set of 41 DNA samples from the 3 major U.S. population groups (African Americans, Caucasians, and Hispanics). The resulting sequence data, which were analyzed with STRait Razor v2.0, revealed 37 unique allele sequence variants that have not been previously reported. Of these, 19 sequences were variations of documented sequences resulting from the presence of intra-repeat SNPs or alternative repeat unit patterns. Despite a limited sampling, two of the most frequently-observed variants were found only in African American samples. The remaining 18 variants represented allele sequences for which there were no published data with which to compare. These findings illustrate the great potential of MPS with regard to increasing the resolving power of STR typing and emphasize the need for sample population characterization of STR alleles.

  11. Genome-wide association study identified a narrow chromosome 1 region associated with chicken growth traits.

    Directory of Open Access Journals (Sweden)

    Liang Xie

    Full Text Available Chicken growth traits are important economic traits in broilers. A large number of studies are available on finding genetic factors affecting chicken growth. However, most of these studies identified chromosome regions containing putative quantitative trait loci and finding causal mutations is still a challenge. In this genome-wide association study (GWAS, we identified a narrow 1.5 Mb region (173.5-175 Mb of chicken (Gallus gallus chromosome (GGA 1 to be strongly associated with chicken growth using 47,678 SNPs and 489 F2 chickens. The growth traits included aggregate body weight (BW at 0-90 d of age measured weekly, biweekly average daily gains (ADG derived from weekly body weight, and breast muscle weight (BMW, leg muscle weight (LMW and wing weight (WW at 90 d of age. Five SNPs in the 1.5 Mb KPNA3-FOXO1A region at GGA1 had the highest significant effects for all growth traits in this study, including a SNP at 8.9 Kb upstream of FOXO1A for BW at 22-48 d and 70 d, a SNP at 1.9 Kb downstream of FOXO1A for WW, a SNP at 20.9 Kb downstream of ENSGALG00000022732 for ADG at 29-42 d, a SNP in INTS6 for BW at 90 d, and a SNP in KPNA3 for BMW and LMW. The 1.5 Mb KPNA3-FOXO1A region contained two microRNA genes that could bind to messenger ribonucleic acid (mRNA of IGF1, FOXO1A and KPNA3. It was further indicated that the 1.5 Mb GGA1 region had the strongest effects on chicken growth during 22-42 d.

  12. Chromosome analysis of arsenic affected cattle

    Directory of Open Access Journals (Sweden)

    S. Shekhar

    2014-10-01

    Full Text Available Aim: The aim was to study the chromosome analysis of arsenic affected cattle. Materials and Methods: 27 female cattle (21 arsenic affected and 6 normal were selected for cytogenetical study. The blood samples were collected, incubated, and cultured using appropriate media and specific methods. The samples were analyzed for chromosome number and morphology, relative length of the chromosome, arm ratio, and centromere index of X chromosome and chromosomal abnormalities in arsenic affected cattle to that of normal ones. Results: The diploid number of metaphase chromosomes in arsenic affected cattle as well as in normal cattle were all 2n=60, 58 being autosomes and 2 being sex chromosomes. From the centromeric position, karyotyping studies revealed that all the 29 pair of autosomes was found to be acrocentric or telocentric, and the sex chromosomes (XX were submetacentric in both normal and arsenic affected cattle. The relative length of all the autosome pairs and sex chrosomosome pair was found to be higher in normal than that of arsenic affected cattle. The mean arm ratio of X-chromosome was higher in normal than that of arsenic affected cattle, but it is reverse in case of centromere index value of X-chromosome. There was no significant difference of arm ratio and centromere index of X-chromosomes between arsenic affected and normal cattle. No chromosomal abnormalities were found in arsenic affected cattle. Conclusion: The chromosome analysis of arsenic affected cattle in West Bengal reported for the first time in this present study which may serve as a guideline for future studies in other species. These reference values will also help in comparison of cytological studies of arsenic affected cattle to that of various toxicants.

  13. The peripheral chromosome scaffold, a novel structural component of mitotic chromosomes.

    Science.gov (United States)

    Sheval, Eugene V; Polyakov, Vladimir Y

    2008-06-01

    Using an original high-salt extraction protocol, we observed a novel chromosome substructure, referred to as the peripheral chromosome scaffold. This chromosome domain contained the perichromosomal layer proteins pKi-67, B23/nucleophosmin and fibrillarin, but no DNA fragments (i.e., the loop domain bases were not associated with the peripheral scaffold). Modern models of chromosome organization do not predict the existence of a peripheral chromosome scaffold domain, and thus our observations have conceptual implications for understanding chromosome architecture. PMID:18337132

  14. Articles selected by Faculty of 1000 Biology: genetically identical SNPs; detailed histone modification mapping; plant gene-expression diversity; photosynthesis gene evolution; ε-Proteobacteria diversity.

    OpenAIRE

    2005-01-01

    A selection of evaluations from Faculty of 1000 Biology covering genetically identical SNPs; detailed histone modification mapping; plant gene-expression diversity; photosynthesis gene evolution; ε-Proteobacteria diversity

  15. SNPs in microRNA binding sites in 3'-UTRs of RAAS genes influence arterial blood pressure and risk of myocardial infarction

    DEFF Research Database (Denmark)

    Nossent, Anne Yaël; Hansen, Jakob Liebe; Doggen, Carine;

    2011-01-01

    We hypothesized that single nucleotide polymorphisms (SNPs) located in microRNA (miR) binding sites in genes of the renin angiotensin aldosterone system (RAAS) can influence blood pressure and risk of myocardial infarction....

  16. XWAS: A Software Toolset for Genetic Data Analysis and Association Studies of the X Chromosome.

    Science.gov (United States)

    Gao, Feng; Chang, Diana; Biddanda, Arjun; Ma, Li; Guo, Yingjie; Zhou, Zilu; Keinan, Alon

    2015-01-01

    XWAS is a new software suite for the analysis of the X chromosome in association studies and similar genetic studies. The X chromosome plays an important role in human disease and traits of many species, especially those with sexually dimorphic characteristics. Special attention needs to be given to its analysis due to the unique inheritance pattern, which leads to analytical complications that have resulted in the majority of genome-wide association studies (GWAS) either not considering X or mishandling it with toolsets that had been designed for non-sex chromosomes. We hence developed XWAS to fill the need for tools that are specially designed for analysis of X. Following extensive, stringent, and X-specific quality control, XWAS offers an array of statistical tests of association, including: 1) the standard test between a SNP (single nucleotide polymorphism) and disease risk, including after first stratifying individuals by sex, 2) a test for a differential effect of a SNP on disease between males and females, 3) motivated by X-inactivation, a test for higher variance of a trait in heterozygous females as compared with homozygous females, and 4) for all tests, a version that allows for combining evidence from all SNPs across a gene. We applied the toolset analysis pipeline to 16 GWAS datasets of immune-related disorders and 7 risk factors of coronary artery disease, and discovered several new X-linked genetic associations. XWAS will provide the tools and incentive for others to incorporate the X chromosome into GWAS and similar studies in any species with an XX/XY system, hence enabling discoveries of novel loci implicated in many diseases and in their sexual dimorphism. PMID:26268243

  17. Deciphering evolutionary strata on plant sex chromosomes and fungal mating-type chromosomes through compositional segmentation.

    Science.gov (United States)

    Pandey, Ravi S; Azad, Rajeev K

    2016-03-01

    Sex chromosomes have evolved from a pair of homologous autosomes which differentiated into sex determination systems, such as XY or ZW system, as a consequence of successive recombination suppression between the gametologous chromosomes. Identifying the regions of recombination suppression, namely, the "evolutionary strata", is central to understanding the history and dynamics of sex chromosome evolution. Evolution of sex chromosomes as a consequence of serial recombination suppressions is well-studied for mammals and birds, but not for plants, although 48 dioecious plants have already been reported. Only two plants Silene latifolia and papaya have been studied until now for the presence of evolutionary strata on their X chromosomes, made possible by the sequencing of sex-linked genes on both the X and Y chromosomes, which is a requirement of all current methods that determine stratum structure based on the comparison of gametologous sex chromosomes. To circumvent this limitation and detect strata even if only the sequence of sex chromosome in the homogametic sex (i.e. X or Z chromosome) is available, we have developed an integrated segmentation and clustering method. In application to gene sequences on the papaya X chromosome and protein-coding sequences on the S. latifolia X chromosome, our method could decipher all known evolutionary strata, as reported by previous studies. Our method, after validating on known strata on the papaya and S. latifolia X chromosome, was applied to the chromosome 19 of Populus trichocarpa, an incipient sex chromosome, deciphering two, yet unknown, evolutionary strata. In addition, we applied this approach to the recently sequenced sex chromosome V of the brown alga Ectocarpus sp. that has a haploid sex determination system (UV system) recovering the sex determining and pseudoautosomal regions, and then to the mating-type chromosomes of an anther-smut fungus Microbotryum lychnidis-dioicae predicting five strata in the non

  18. Distinct Patterns of Association of Variants at 11q23.3 Chromosomal Region with Coronary Artery Disease and Dyslipidemia in the Population of Andhra Pradesh, India.

    Directory of Open Access Journals (Sweden)

    Rayabarapu Pranav Chand

    Full Text Available In our attempt to comprehensively understand the nature of association of variants at 11q23.3 apolipoprotein gene cluster region, we genotyped a prioritized set of 96 informative SNPs using Fluidigm customized SNP genotyping platform in a sample of 508 coronary artery disease (CAD cases and 516 controls. We found 12 SNPs as significantly associated with CAD at P <0.05, albeit only four (rs2849165, rs17440396, rs6589566 and rs633389 of these remained significant after Benjamin Hochberg correction. Of the four, while rs6589566 confers risk to CAD, the other three SNPs reduce risk for the disease. Interaction of variants that belong to regulatory genes BUD13 and ZPR1 with APOA5-APOA4 intergenic variants is also observed to significantly increase the risk towards CAD. Further, ROC analysis of the risk scores of the 12 significant SNPs suggests that our study has substantial power to confer these genetic variants as predictors of risk for CAD, as illustrated by AUC (0.763; 95% CI: 0.729-0.798, p = <0.0001. On the other hand, the protective SNPs of CAD are associated with elevated Low Density Lipoprotein Cholesterol and Total Cholesterol levels, hence with dyslipidemia, in our sample of controls, which may suggest distinct effects of the variants at 11q23.3 chromosomal region towards CAD and dyslipidemia. It may be necessary to replicate these findings in the independent and ethnically heterogeneous Indian samples in order to establish this as an Indian pattern. However, only functional analysis of the significant variants identified in our study can provide more precise understanding of the mechanisms involved in the contrasting nature of their effects in manifesting dyslipidemia and CAD.

  19. Distinct Patterns of Association of Variants at 11q23.3 Chromosomal Region with Coronary Artery Disease and Dyslipidemia in the Population of Andhra Pradesh, India.

    Science.gov (United States)

    Pranav Chand, Rayabarapu; Kumar, Arramraju Sreenivas; Anuj, Kapadia; Vishnupriya, Satti; Mohan Reddy, Battini

    2016-01-01

    In our attempt to comprehensively understand the nature of association of variants at 11q23.3 apolipoprotein gene cluster region, we genotyped a prioritized set of 96 informative SNPs using Fluidigm customized SNP genotyping platform in a sample of 508 coronary artery disease (CAD) cases and 516 controls. We found 12 SNPs as significantly associated with CAD at P <0.05, albeit only four (rs2849165, rs17440396, rs6589566 and rs633389) of these remained significant after Benjamin Hochberg correction. Of the four, while rs6589566 confers risk to CAD, the other three SNPs reduce risk for the disease. Interaction of variants that belong to regulatory genes BUD13 and ZPR1 with APOA5-APOA4 intergenic variants is also observed to significantly increase the risk towards CAD. Further, ROC analysis of the risk scores of the 12 significant SNPs suggests that our study has substantial power to confer these genetic variants as predictors of risk for CAD, as illustrated by AUC (0.763; 95% CI: 0.729-0.798, p = <0.0001). On the other hand, the protective SNPs of CAD are associated with elevated Low Density Lipoprotein Cholesterol and Total Cholesterol levels, hence with dyslipidemia, in our sample of controls, which may suggest distinct effects of the variants at 11q23.3 chromosomal region towards CAD and dyslipidemia. It may be necessary to replicate these findings in the independent and ethnically heterogeneous Indian samples in order to establish this as an Indian pattern. However, only functional analysis of the significant variants identified in our study can provide more precise understanding of the mechanisms involved in the contrasting nature of their effects in manifesting dyslipidemia and CAD. PMID:27257688

  20. Design of a high density SNP genotyping assay in the pig using SNPs identified and characterized by next generation sequencing technology.

    Directory of Open Access Journals (Sweden)

    Antonio M Ramos

    Full Text Available BACKGROUND: The dissection of complex traits of economic importance to the pig industry requires the availability of a significant number of genetic markers, such as single nucleotide polymorphisms (SNPs. This study was conducted to discover several hundreds of thousands of porcine SNPs using next generation sequencing technologies and use these SNPs, as well as others from different public sources, to design a high-density SNP genotyping assay. METHODOLOGY/PRINCIPAL FINDINGS: A total of 19 reduced representation libraries derived from four swine breeds (Duroc, Landrace, Large White, Pietrain and a Wild Boar population and three restriction enzymes (AluI, HaeIII and MspI were sequenced using Illumina's Genome Analyzer (GA. The SNP discovery effort resulted in the de novo identification of over 372K SNPs. More than 549K SNPs were used to design the Illumina Porcine 60K+SNP iSelect Beadchip, now commercially available as the PorcineSNP60. A total of 64,232 SNPs were included on the Beadchip. Results from genotyping the 158 individuals used for sequencing showed a high overall SNP call rate (97.5%. Of the 62,621 loci that could be reliably scored, 58,994 were polymorphic yielding a SNP conversion success rate of 94%. The average minor allele frequency (MAF for all scorable SNPs was 0.274. CONCLUSIONS/SIGNIFICANCE: Overall, the results of this study indicate the utility of using next generation sequencing technologies to identify large numbers of reliable SNPs. In addition, the validation of the PorcineSNP60 Beadchip demonstrated that the assay is an excellent tool that will likely be used in a variety of future studies in pigs.

  1. Chromosome engineering: power tools for plant genetics.

    Science.gov (United States)

    Chan, Simon W L

    2010-12-01

    The term "chromosome engineering" describes technologies in which chromosomes are manipulated to change their mode of genetic inheritance. This review examines recent innovations in chromosome engineering that promise to greatly increase the efficiency of plant breeding. Haploid Arabidopsis thaliana have been produced by altering the kinetochore protein CENH3, yielding instant homozygous lines. Haploid production will facilitate reverse breeding, a method that downregulates recombination to ensure progeny contain intact parental chromosomes. Another chromosome engineering success is the conversion of meiosis into mitosis, which produces diploid gametes that are clones of the parent plant. This is a key step in apomixis (asexual reproduction through seeds) and could help to preserve hybrid vigor in the future. New homologous recombination methods in plants will potentiate many chromosome engineering applications. PMID:20933291

  2. Radiation induced chromosome instability in human fibroblasts

    International Nuclear Information System (INIS)

    Evidence has been arising that some biological effects can manifest many cell divisions after irradiation. We have demonstrated that de novo chromosome instability can be detected 10- 15 mean population doubling after heavy ion irradiations. This chromosome instability is characterized by end to end fusions between specific chromosomes. The specificity of the instability may differ from one donor to another but for the same donor, the same instability should be observed after irradiation, during the senescence process and after SV40 transfection (before crisis). In irradiated primary culture fibroblasts, the expression of the delayed chromosomal instability lasts for several cell divisions without inducing cell death. Several rounds of fusions- breakage-fusions can be performed and unbalanced clones emerge (gain or loss of chromosomes with the shorter telomeres would become unstable first.. The difference in the chromosomal instability among donors could be due to a polymorphism in telomere lengths. This could induce large variation in long term response to irradiation among individuals. (author)

  3. Association of SNPs in interferon receptor genes in chronic hepatitis C with response to combined therapy of interferon and ribavirin.

    Directory of Open Access Journals (Sweden)

    Zohreh Heidari

    2014-10-01

    Full Text Available Hepatitis C Virus is one of the main reasons for chronic liver disease and hepatocellular carcinoma. Combination therapy with Interferon (peg-IFN-α and Ribavirin (RBV clear the virus more likely than the others. Different factors like virus and host characteristics influence on response to treatment. The most important viral factors include virus genotype and viral load; host factors like genetic, gender, race, age, weight and liver enzymes are also important. Previous studies have shown that single nucleotide polymorphisms (SNPs in IFNR genes can regulate and influence on treatment with IFN. The purpose of this study is to investigate the association between SNPs in IFN-α receptor (IFNAR1 & IFNAR2 genes among subjects affected with chronic hepatitis C, who have treated with IFN and RBV, and also relationship between HCV genotypes and response to combination antiviral therapy. Peripheral blood mononuclear cells (PBMCs were taken from whole blood of 61 patients affected with chronic hepatitis C who were treated with IFN and Ribavirin. Then, DNA was extracted from PBMCs and quality of DNA was assessed with Nanodrop finally two SNPs [Ex4-30G>C] and [Ivs1-4640 G>A] of IFN receptor genes (IFNAR1 and IFNAR2 were measured by TaqMan Real-Time PCR in ABi Prism 7900 system. Also to confirm the response rate to therapy, RNA was extracted then RT PCR was performed and final product was studied with gel electrophoresis and UV spectroscopy. Statistical analysis was performed using SPSS version 18.0 for Windows. The analysis of results from TaqMan SNP Genotyping has been shown that two SNPs (Ex4-30G>C and Ivs1-4640 G>A of IFNAR1 and IFNAR2 didn't show any relationship with response to combined therapy in subjects affected with chronic hepatitis C who have treated with peg-IFN-α and Ribavirin. 61 patients complete the treatment period. 54 patients (%88/5 of them responded to treatment and 7 patients (%11/5 did not. Research and data analysis have shown that

  4. Fine mapping of genetic polymorphisms of pulmonary tuberculosis within chromosome 18q11.2 in the Chinese population: a case-control study

    Directory of Open Access Journals (Sweden)

    Dai Yaoyao

    2011-10-01

    Full Text Available Abstract Background Recently, one genome-wide association study identified a susceptibility locus of rs4331426 on chromosome 18q11.2 for tuberculosis in the African population. To validate the significance of this susceptibility locus in other areas, we conducted a case-control study in the Chinese population. Methods The present study consisted of 578 cases and 756 controls. The SNP rs4331426 and other six tag SNPs in the 100 Kbp up and down stream of rs4331426 on chromosome 18q11.2 were genotyped by using the Taqman-based allelic discrimination system. Results As compared with the findings from the African population, genetic variation of the SNP rs4331426 was rare among the Chinese. No significant differences were observed in genotypes or allele frequencies of the tag SNPs between cases and controls either before or after adjusting for age, sex, education, smoking, and drinking history. However, we observed strong linkage disequilibrium of SNPs. Constructed haplotypes within this block were linked the altered risks of tuberculosis. For example, in comparison with the common haplotype AA(rs8087945-rs12456774, haplotypes AG(rs8087945-rs12456774 and GA(rs8087945-rs12456774 were associated with a decreased risk of tuberculosis, with the adjusted odds ratio(95% confidence interval of 0.34(0.27-0.42 and 0.22(0.16-0.29, respectively. Conclusions Susceptibility locus of rs4331426 discovered in the African population could not be validated in the Chinese population. None of genetic polymorphisms we genotyped were related to tuberculosis in the single-point analysis. However, haplotypes on chromosome 18q11.2 might contribute to an individual's susceptibility. More work is necessary to identify the true causative variants of tuberculosis.

  5. Meiosis I: When Chromosomes Undergo Extreme Makeover

    OpenAIRE

    Miller, Matthew P.; Amon, Angelika; Ünal, Elçin

    2013-01-01

    The ultimate success of cell division relies on the accurate partitioning of the genetic material. Errors in this process occur in nearly all tumors and are the leading cause of miscarriages and congenital birth defects in humans. Two cell divisions, mitosis and meiosis, use common as well as unique mechanisms to ensure faithful chromosome segregation. In mitosis, alternating rounds of DNA replication and chromosome segregation preserves the chromosome complement of the progenitor cell. In co...

  6. Novel Gene Acquisition on Carnivore Y Chromosomes

    OpenAIRE

    Murphy, William J.; A J Pearks Wilkerson; Terje Raudsepp; Richa Agarwala; Schäffer, Alejandro A.; Roscoe Stanyon; Chowdhary, Bhanu P

    2006-01-01

    Despite its importance in harboring genes critical for spermatogenesis and male-specific functions, the Y chromosome has been largely excluded as a priority in recent mammalian genome sequencing projects. Only the human and chimpanzee Y chromosomes have been well characterized at the sequence level. This is primarily due to the presumed low overall gene content and highly repetitive nature of the Y chromosome and the ensuing difficulties using a shotgun sequence approach for assembly. Here we...

  7. Identification of bacterial cells by chromosomal painting.

    OpenAIRE

    Lanoil, B. D.; Giovannoni, S J

    1997-01-01

    Chromosomal painting is a technique for the microscopic localization of genetic material. It has been applied at the subcellular level to identify regions of eukaryotic chromosomes. Here we describe the development of bacterial chromosomal painting (BCP), a related technology for the identification of bacterial cells. Purified genomic DNAs from six bacterial strains were labeled by nick translation with the fluorochrome Fluor-X, Cy3, or Cy5. The average size of the labeled fragments was ca. 5...

  8. Holoprosencephaly due to Numeric Chromosome Abnormalities

    OpenAIRE

    Solomon, Benjamin D.; Rosenbaum, Kenneth N.; Meck, Jeanne M.; Muenke, Maximilian

    2010-01-01

    Holoprosencephaly (HPE) is the most common malformation of the human forebrain. When a clinician identifies a patient with HPE, a routine chromosome analysis is often the first genetic test sent for laboratory analysis in order to assess for a structural or numerical chromosome anomaly. An abnormality of chromosome number is overall the most frequently identified etiology in a patient with HPE. These abnormalities include trisomy 13, trisomy 18, and triploidy, though several others have been ...

  9. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH RECURRENT MISCARRIAGE

    OpenAIRE

    Daniela Mierla; Viorica Radoi; Veronica Stoian

    2012-01-01

    Chromosomal abnormalities are involved in the etiology of recurrent spontaneous pregnancy loss and sub-fertility. The purpose of this study was to determine the frequency and contribution of chromosomal abnormalities in recurrent miscarriages. The results obtained and literature review are helpful in understanding the importance of cytogenetics analysis of female infertility. To investigate the distribution of chromosomal abnormalities in the Romanian population with recurrent miscarriage, ka...

  10. How does DNA break during chromosomal translocations?

    OpenAIRE

    Nambiar, Mridula; Raghavan, Sathees C.

    2011-01-01

    Chromosomal translocations are one of the most common types of genetic rearrangements and are molecular signatures for many types of cancers. They are considered as primary causes for cancers, especially lymphoma and leukemia. Although many translocations have been reported in the last four decades, the mechanism by which chromosomes break during a translocation remains largely unknown. In this review, we summarize recent advances made in understanding the molecular mechanism of chromosomal t...

  11. Evaluation of GWAS-identified SNPs at 6p22 with neuroblastoma susceptibility in a Chinese population.

    Science.gov (United States)

    He, Jing; Zhang, Ruizhong; Zou, Yan; Zhu, Jinhong; Yang, Tianyou; Wang, Fenghua; Xia, Huimin

    2016-02-01

    Previous genome-wide association studies (GWASs) have reported that three single nucleotide polymorphisms (SNPs) (rs6939340 A>G, rs4712653 T>C, and rs9295536 C>A) located at 6p22 locus were associated with neuroblastoma susceptibility for Caucasian descent. We conducted this hospital-based case-control study with 201 neuroblastoma patients and 531 controls to investigate the association between these three SNPs in the FLJ22536 gene with neuroblastoma susceptibility in the Chinese Han population. The odds ratio (OR) and 95 % confidence interval (CI) were calculated to estimate the strength of the association using unconditional logistic regression model. We found that the rs6939340 A allele carriers were associated with significantly decreased neuroblastoma susceptibility (AG vs. GG: adjusted OR = 0.54, 95 % CI = 0.38-0.77; AA vs. GG: adjusted OR = 0.49, 95 % CI = 0.25-0.93; and AA/AG vs. GG: adjusted OR = 0.53, 95 % CI = 0.38-0.74) after adjustment for age and gender. The protective association between variant allele and neuroblastoma susceptibility was also observed for the rs4712653 and rs9295536 polymorphisms. Moreover, we found that subjects carrying one or more protective genotypes had a much lower neuroblastoma susceptibility than non-carriers (adjusted OR = 0.60, 95 % CI = 0.43-0.83). Our study verified that the associations between all of the three SNPs in the 6p22 locus are associated with neuroblastoma susceptibility in the Chinese subjects. Further prospective multicenter studies with different ethnicities and larger sample size are needed to validate our findings. PMID:26307394

  12. Characterization of the linkage disequilibrium structure and identification of tagging-SNPs in five DNA repair genes

    International Nuclear Information System (INIS)

    Characterization of the linkage disequilibrium (LD) structure of candidate genes is the basis for an effective association study of complex diseases such as cancer. In this study, we report the LD and haplotype architecture and tagging-single nucleotide polymorphisms (tSNPs) for five DNA repair genes: ATM, MRE11A, XRCC4, NBS1 and RAD50. The genes ATM, MRE11A, and XRCC4 were characterized using a panel of 94 unrelated female subjects (47 breast cancer cases, 47 controls) obtained from high-risk breast cancer families. A similar LD structure and tSNP analysis was performed for NBS1 and RAD50, using publicly available genotyping data. We studied a total of 61 SNPs at an average marker density of 10 kb. Using a matrix decomposition algorithm, based on principal component analysis, we captured >90% of the intragenetic variation for each gene. Our results revealed that three of the five genes did not conform to a haplotype block structure (MRE11A, RAD50 and XRCC4). Instead, the data fit a more flexible LD group paradigm, where SNPs in high LD are not required to be contiguous. Traditional haplotype blocks assume recombination is the only dynamic at work. For ATM, MRE11A and XRCC4 we repeated the analysis in cases and controls separately to determine whether LD structure was consistent across breast cancer cases and controls. No substantial difference in LD structures was found. This study suggests that appropriate SNP selection for an association study involving candidate genes should allow for both mutation and recombination, which shape the population-level genomic structure. Furthermore, LD structure characterization in either breast cancer cases or controls appears to be sufficient for future cancer studies utilizing these genes

  13. Risk-Association of Five SNPs in TOX3/LOC643714 with Breast Cancer in Southern China

    Directory of Open Access Journals (Sweden)

    Xuanqiu He

    2014-01-01

    Full Text Available The specific mechanism by which low-risk genetic variants confer breast cancer risk is currently unclear, with contradictory evidence on the role of single nucleotide polymorphisms (SNPs in TOX3/LOC643714 as a breast cancer susceptibility locus. Investigations of this locus using a Chinese population may indicate whether the findings initially identified in a European population are generalizable to other populations, and may provide new insight into the role of genetic variants in the etiology of breast cancer. In this case-control study, 623 Chinese female breast cancer patients and 620 cancer-free controls were recruited to investigate the role of five SNPs in TOX3/LOC643714 (rs8051542, rs12443621, rs3803662, rs4784227, and rs3112612; Linkage disequilibrium (LD pattern analysis was performed. Additionally, we evaluated how these common SNPs influence the risk of specific types of breast cancer, as defined by estrogen receptor (ER status, progesterone receptor (PR status and human epidermal growth factor receptor 2 (HER2 status. Significant associations with breast cancer risk were observed for rs4784227 and rs8051542 with odds ratios (OR of 1.31 ((95% confidence intervals (CI, 1.10–1.57 and 1.26 (95% CI, 1.02–1.56, respectively, per T allele. The T-rs8051542 allele was significantly associated with ER-positive and HER2-negative carriers. No significant association existed between rs12443621, rs3803662, and rs3112612 polymorphisms and risk of breast cancer. Our results support the hypothesis that the applicability of a common susceptibility locus must be confirmed among genetically different populations, which may together explain an appreciable fraction of the genetic etiology of breast cancer.

  14. Characterization of the linkage disequilibrium structure and identification of tagging-SNPs in five DNA repair genes

    Directory of Open Access Journals (Sweden)

    Camp Nicola J

    2005-08-01

    Full Text Available Abstract Background Characterization of the linkage disequilibrium (LD structure of candidate genes is the basis for an effective association study of complex diseases such as cancer. In this study, we report the LD and haplotype architecture and tagging-single nucleotide polymorphisms (tSNPs for five DNA repair genes: ATM, MRE11A, XRCC4, NBS1 and RAD50. Methods The genes ATM, MRE11A, and XRCC4 were characterized using a panel of 94 unrelated female subjects (47 breast cancer cases, 47 controls obtained from high-risk breast cancer families. A similar LD structure and tSNP analysis was performed for NBS1 and RAD50, using publicly available genotyping data. We studied a total of 61 SNPs at an average marker density of 10 kb. Using a matrix decomposition algorithm, based on principal component analysis, we captured >90% of the intragenetic variation for each gene. Results Our results revealed that three of the five genes did not conform to a haplotype block structure (MRE11A, RAD50 and XRCC4. Instead, the data fit a more flexible LD group paradigm, where SNPs in high LD are not required to be contiguous. Traditional haplotype blocks assume recombination is the only dynamic at work. For ATM, MRE11A and XRCC4 we repeated the analysis in cases and controls separately to determine whether LD structure was consistent across breast cancer cases and controls. No substantial difference in LD structures was found. Conclusion This study suggests that appropriate SNP selection for an association study involving candidate genes should allow for both mutation and recombination, which shape the population-level genomic structure. Furthermore, LD structure characterization in either breast cancer cases or controls appears to be sufficient for future cancer studies utilizing these genes.

  15. Effect prediction of identified SNPs linked to fruit quality and chilling injury in peach [Prunus persica (L.) Batsch].

    Science.gov (United States)

    Martínez-García, Pedro J; Fresnedo-Ramírez, Jonathan; Parfitt, Dan E; Gradziel, Thomas M; Crisosto, Carlos H

    2013-01-01

    Single nucleotide polymorphisms (SNPs) are a fundamental source of genomic variation. Large SNP panels have been developed for Prunus species. Fruit quality traits are essential peach breeding program objectives since they determine consumer acceptance, fruit consumption, industry trends and cultivar adoption. For many cultivars, these traits are negatively impacted by cold storage, used to extend fruit market life. The major symptoms of chilling injury are lack of flavor, off flavor, mealiness, flesh browning, and flesh bleeding. A set of 1,109 SNPs was mapped previously and 67 were linked with these complex traits. The prediction of the effects associated with these SNPs on downstream products from the 'peach v1.0' genome sequence was carried out. A total of 2,163 effects were detected, 282 effects (non-synonymous, synonymous or stop codon gained) were located in exonic regions (13.04 %) and 294 placed in intronic regions (13.59 %). An extended list of genes and proteins that could be related to these traits was developed. Two SNP markers that explain a high percentage of the observed phenotypic variance, UCD_SNP_1084 and UCD_SNP_46, are associated with zinc finger (C3HC4-type RING finger) family protein and AOX1A (alternative oxidase 1a) protein groups, respectively. In addition, phenotypic variation suggests that the observed polymorphism for SNP UCD_SNP_1084 [A/G] mutation could be a candidate quantitative trait nucleotide affecting quantitative trait loci for mealiness. The interaction and expression of affected proteins could explain the variation observed in each individual and facilitate understanding of gene regulatory networks for fruit quality traits in peach. PMID:23184287

  16. Transcriptome Analysis of an Insecticide Resistant Housefly Strain: Insights about SNPs and Regulatory Elements in Cytochrome P450 Genes

    Science.gov (United States)

    Asp, Torben; Kristensen, Michael

    2016-01-01

    Background Insecticide resistance in the housefly, Musca domestica, has been investigated for more than 60 years. It will enter a new era after the recent publication of the housefly genome and the development of multiple next generation sequencing technologies. The genetic background of the xenobiotic response can now be investigated in greater detail. Here, we investigate the 454-pyrosequencing transcriptome of the spinosad-resistant 791spin strain in relation to the housefly genome with focus on P450 genes. Results The de novo assembly of clean reads gave 35,834 contigs consisting of 21,780 sequences of the spinosad resistant strain. The 3,648 sequences were annotated with an enzyme code EC number and were mapped to 124 KEGG pathways with metabolic processes as most highly represented pathway. One hundred and twenty contigs were annotated as P450s covering 44 different P450 genes of housefly. Eight differentially expressed P450s genes were identified and investigated for SNPs, CpG islands and common regulatory motifs in promoter and coding regions. Functional annotation clustering of metabolic related genes and motif analysis of P450s revealed their association with epigenetic, transcription and gene expression related functions. The sequence variation analysis resulted in 12 SNPs and eight of them found in cyp6d1. There is variation in location, size and frequency of CpG islands and specific motifs were also identified in these P450s. Moreover, identified motifs were associated to GO terms and transcription factors using bioinformatic tools. Conclusion Transcriptome data of a spinosad resistant strain provide together with genome data fundamental support for future research to understand evolution of resistance in houseflies. Here, we report for the first time the SNPs, CpG islands and common regulatory motifs in differentially expressed P450s. Taken together our findings will serve as a stepping stone to advance understanding of the mechanism and role of P450s

  17. The development of a high density linkage map for black tiger shrimp (Penaeus monodon based on cSNPs.

    Directory of Open Access Journals (Sweden)

    Matthew Baranski

    Full Text Available Transcriptome sequencing using Illumina RNA-seq was performed on populations of black tiger shrimp from India. Samples were collected from (i four landing centres around the east coastline (EC of India, (ii survivors of a severe WSSV infection during pond culture (SUR and (iii the Andaman Islands (AI in the Bay of Bengal. Equal quantities of purified total RNA from homogenates of hepatopancreas, muscle, nervous tissue, intestinal tract, heart, gonad, gills, pleopod and lymphoid organs were combined to create AI, EC and SUR pools for RNA sequencing. De novo transcriptome assembly resulted in 136,223 contigs (minimum size 100 base pairs, bp with a total length 61 Mb, an average length of 446 bp and an average coverage of 163× across all pools. Approximately 16% of contigs were annotated with BLAST hit information and gene ontology annotations. A total of 473,620 putative SNPs/indels were identified. An Illumina iSelect genotyping array containing 6,000 SNPs was developed and used to genotype 1024 offspring belonging to seven full-sibling families. A total of 3959 SNPs were mapped to 44 linkage groups. The linkage groups consisted of between 16-129 and 13-130 markers, of length between 139-10.8 and 109.1-10.5 cM and with intervals averaging between 1.2 and 0.9 cM for the female and male maps respectively. The female map was 28% longer than the male map (4060 and 2917 cM respectively with a 1.6 higher recombination rate observed for female compared to male meioses. This approach has substantially increased expressed sequence and DNA marker resources for tiger shrimp and is a useful resource for QTL mapping and association studies for evolutionarily and commercially important traits.

  18. Advances in plant chromosome genomics

    Czech Academy of Sciences Publication Activity Database

    Doležel, Jaroslav; Vrána, Jan; Cápal, Petr; Kubaláková, Marie; Burešová, Veronika; Šimková, Hana

    2014-01-01

    Roč. 32, č. 1 (2014), s. 122-136. ISSN 0734-9750 R&D Projects: GA ČR GAP501/10/1740; GA ČR GAP501/10/1778; GA ČR GBP501/12/G090; GA MŠk(CZ) LO1204 Grant ostatní: GA MŠk(CZ) ED0007/01/01 Institutional support: RVO:61389030 Keywords : BAC library * Chromosome sorting * Cytogenetics Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 9.015, year: 2014

  19. Multiple chromosomes of Azotobacter vinelandii.

    OpenAIRE

    1989-01-01

    The number of copies of the genes leuB, nifH, nifD, and nifK per cell of Azotobacter vinelandii has been determined to be about 80. A beta-lactamase gene was integrated into the A. vinelandii chromosome by single-point crossover. Subsequently, we have been able to detect nearly 80 copies of this beta-lactamase gene per cell of A. vinelandii when cultured for a large number of generations in the presence of ampicillin. The multiple copies of the beta-lactamase gene do not seem to be present on...

  20. Chromosome banding in Amphibia. XXIV. The B chromosomes of Gastrotheca espeletia (Anura, Hylidae).

    Science.gov (United States)

    Schmid, M; Ziegler, C G; Steinlein, C; Nanda, I; Haaf, T

    2002-01-01

    The mitotic chromosomes of an Ecuadorian population of the marsupial frog Gastrotheca espeletia were analyzed by means of banding techniques and fluorescence in situ hybridization. This species is characterized by unusual supernumerary (B) chromosomes. The maximum number of B chromosomes is 9 and they occur in three different morphological types. Banding analyses show that the B chromosomes are completely heterochromatic, consist of AT base pair-rich repeated DNA sequences, replicate their DNA in very late S-phase of the cell cycle, and are probably derived from a centromeric or paracentromeric region of a standard (A) chromosome. Exceptionally, the B chromosomes carry 18S + 28S ribosomal RNA genes and the conserved vertebrate telomeric DNA sequence appears to be underrepresented. Flow cytometric measurements of the nuclear DNA content differentiate between individuals with different numbers of B chromosomes. Significantly more B chromosomes are present in female than in male animals. PMID:12438715

  1. Giemsa C-banding of Barley Chromosomes. IV. Chromosomal Constitution of Autotetraploid Barley

    DEFF Research Database (Denmark)

    Linde-Laursen, Ib

    1984-01-01

    homologues of each of the chromosomes. The aneuploid C2--seedlings were fairly equally distributed on hypo-and hyperploids, and on the seven chromosome groups. This suggests that a particular chromosome is lost or gained at random in gametes and embryos. The 11 C3--seedlings comprised seven true euploids......The progeny of an autotetraploid barley plant (C1) consisted of 45 tetraploids and 33 aneuploids. Giemsa C-banding was used to identify each of the chromosomes in 20 euploid and 31 aneuploid C2--seedlings, and in 11 C3--offspring of aneuploid C2--plants. The euploid C2--seedlings all had four......, one seedling with 2n=28 having an extra chromosome 6 and missing one chromosome 3, and three seedlings with 2n=29. The chromosomal composition of aneuploid C3--seedlings did not reflect that of their aneuploid C2--parents with respect to missing or extra chromosomes. Two hypohexaploid C2--seedlings...

  2. LRRK2 gene G2019S mutation and SNPs [haplotypes] in subtypes of Parkinson’s disease

    OpenAIRE

    Patra, Biswanath; Parsian, Azemat J.; Racette, Brad A.; Zhao, Jing Hua; Perlmutter, Joel. S.; Parsian, Abbas

    2008-01-01

    Mutation within the Leucine-rich repeat kinase 2 (LRRK2) gene has been identified as a cause of autosomal dominant Parkinson’s disease (PD). The purpose of this study was to determine the frequency of G2019S mutation and whether the differences in the allele and genotype distribution of six SNPs within LRRK2 gene are associated with PD in an American non-Hispanic white population. The sample included 350 sporadic PD (SPD), 225 familial PD (FPD) patients and 186 controls of the same race and e...

  3. SNiPlay: a web-based tool for detection, management and analysis of SNPs. Application to grapevine diversity projects

    Directory of Open Access Journals (Sweden)

    Peros Jean-Pierre

    2011-05-01

    Full Text Available Abstract Background High-throughput re-sequencing, new genotyping technologies and the availability of reference genomes allow the extensive characterization of Single Nucleotide Polymorphisms (SNPs and insertion/deletion events (indels in many plant species. The rapidly increasing amount of re-sequencing and genotyping data generated by large-scale genetic diversity projects requires the development of integrated bioinformatics tools able to efficiently manage, analyze, and combine these genetic data with genome structure and external data. Results In this context, we developed SNiPlay, a flexible, user-friendly and integrative web-based tool dedicated to polymorphism discovery and analysis. It integrates: 1 a pipeline, freely accessible through the internet, combining existing softwares with new tools to detect SNPs and to compute different types of statistical indices and graphical layouts for SNP data. From standard sequence alignments, genotyping data or Sanger sequencing traces given as input, SNiPlay detects SNPs and indels events and outputs submission files for the design of Illumina's SNP chips. Subsequently, it sends sequences and genotyping data into a series of modules in charge of various processes: physical mapping to a reference genome, annotation (genomic position, intron/exon location, synonymous/non-synonymous substitutions, SNP frequency determination in user-defined groups, haplotype reconstruction and network, linkage disequilibrium evaluation, and diversity analysis (Pi, Watterson's Theta, Tajima's D. Furthermore, the pipeline allows the use of external data (such as phenotype, geographic origin, taxa, stratification to define groups and compare statistical indices. 2 a database storing polymorphisms, genotyping data and grapevine sequences released by public and private projects. It allows the user to retrieve SNPs using various filters (such as genomic position, missing data, polymorphism type, allele frequency, to

  4. CYP2B6 SNPs are associated with methadone dose required for effective treatment of opioid addiction

    OpenAIRE

    Levran, Orna; Peles, Einat; Hamon, Sara; Randesi, Matthew; Adelson, Miriam; Kreek, Mary Jeanne

    2011-01-01

    Adequate methadone dosing in methadone maintenance treatment (MMT) for opioid addiction is critical for therapeutic success. One of the challenges in dose determination is the inter-individual variability in dose response. Methadone metabolism is attributed primarily to cytochrome P450 enzymes CYP3A4, CYP2B6, and CYP2D6. The CYP2B6*6 allele [SNPs 785A>G (rs2279343) and 516G>T (rs3745274)] was associated with slow methadone metabolism. To explore the effects of CYP2B6*6 allele on methadone dos...

  5. Microtubule detyrosination guides chromosomes during mitosis

    OpenAIRE

    Barisic, Marin; Silva e Sousa, Ricardo; Tripathy, Suvranta K.; Magiera, Maria M.; Zaytsev, Anatoly V.; Pereira, Ana L.; Janke, Carsten; Grishchuk, Ekaterina L.; Maiato, Helder

    2015-01-01

    Before chromosomes segregate into daughter cells they align at the mitotic spindle equator, a process known as chromosome congression. CENP-E/Kinesin-7 is a microtubule plus-end-directed kinetochore motor required for congression of pole-proximal chromosomes. Because the plus-ends of many astral microtubules in the spindle point to the cell cortex, it remains unknown how CENP-E guides pole-proximal chromosomes specifically towards the equator. Here we found that congression of pole-proximal c...

  6. Exceptional Complex Chromosomal Rearrangements in Three Generations

    Directory of Open Access Journals (Sweden)

    Hannie Kartapradja

    2015-01-01

    Full Text Available We report an exceptional complex chromosomal rearrangement (CCR found in three individuals in a family that involves 4 chromosomes with 5 breakpoints. The CCR was ascertained in a phenotypically abnormal newborn with additional chromosomal material on the short arm of chromosome 4. Maternal karyotyping indicated that the mother carried an apparently balanced CCR involving chromosomes 4, 6, 11, and 18. Maternal transmission of the derivative chromosome 4 resulted in partial trisomy for chromosomes 6q and 18q and a partial monosomy of chromosome 4p in the proband. Further family studies found that the maternal grandmother carried the same apparently balanced CCR as the proband’s mother, which was confirmed using the whole chromosome painting (WCP FISH. High resolution whole genome microarray analysis of DNA from the proband’s mother found no evidence for copy number imbalance in the vicinity of the CCR translocation breakpoints, or elsewhere in the genome, providing evidence that the mother’s and grandmother’s CCRs were balanced at a molecular level. This structural rearrangement can be categorized as an exceptional CCR due to its complexity and is a rare example of an exceptional CCR being transmitted in balanced and/or unbalanced form across three generations.

  7. Chromosome heteromorphisms in the Japanese, 3

    International Nuclear Information System (INIS)

    The type and frequency of chromosome variants detected by the C-staining method were ascertained in 1,857 individuals residing in Hiroshima. The most frequent heteromorphic variant was the total inversion of the C-band in chromosome 9 found in 27 individuals (1.45%). The total inversion of the C-band in chromosome 1 was not seen in this sample, but the partial inversion of the C-band in chromosome 1 was found in 18 persons (0.97%). Partial inversion was also detected in the C-band in chromosome 9 in 22 individuals (1.18%). In chromosome 16, neither total nor partial inversion of the C-band was observed in the present study. The frequencies of chromosomes 1, 9, and 16 with a very large C-band were 0.70%, 0.22%, and 0.54%, respectively. Aside from these (1, 9, and 16) a very large C-band was found occasionally in chromosomes 4, 5, 6, 11, 12, 14, and 15, and an unusual insertion of the Y chromosome was observed. A total of 128 C-band variants (6.89%) was found in the 1,857 Hiroshima residents. (author)

  8. Cognitive and medical features of chromosomal aneuploidy.

    Science.gov (United States)

    Hutaff-Lee, Christa; Cordeiro, Lisa; Tartaglia, Nicole

    2013-01-01

    This chapter describes the physical characteristics, medical complications, and cognitive and psychological profiles that are associated with chromosomal aneuploidy conditions, a group of conditions in which individuals are born with one or more additional chromosome. Overall, chromosomal aneuploidy conditions occur in approximately 1 in 250 children. Information regarding autosomal disorders including trisomy 21 (Down syndrome), trisomy 13 (Patau syndrome), and trisomy 18 (Edward syndrome) are presented. Sex chromosome aneuploidy conditions such as Klinefelter syndrome (47,XXY), XYY, trisomy X, and Turner syndrome (45,X), in addition to less frequently occurring tetrasomy and pentasomy conditions are also covered. Treatment recommendations and suggestions for future research directions are discussed. PMID:23622175

  9. Chromosomal aberrations in ore miners of Slovakia

    International Nuclear Information System (INIS)

    A pilot study was performed in which the incidence of chromosomal aberrations in lymphocytes of miners in ore mines located in Central Slovakia was monitored and related to lifetime underground radon exposure and to lifetime smoking. The conclusions drawn from the results of the study were as follows: the counts of chromosomal aberrations in lymphocytes of miners were significantly higher than in an age matched control group of white-collar staff; the higher counts of chromosomal aberrations could be ascribed to underground exposure of miners and to smoking; a dependence of chromosomal aberration counts on the exposure to radon could not be assessed. (A.K.)

  10. Proteogenomic Study beyond Chromosome 9: New Insight into Expressed Variant Proteome and Transcriptome in Human Lung Adenocarcinoma Tissues.

    Science.gov (United States)

    Kim, Yong-In; Lee, Jongan; Choi, Young-Jin; Seo, Jawon; Park, Jisook; Lee, Soo-Youn; Cho, Je-Yoel

    2015-12-01

    This is a report of a human proteome project (HPP) related to chromosome 9 (Chr 9). To reveal missing proteins and undiscovered features in proteogenomes, both LC-MS/MS analysis and next-generation RNA sequencing (RNA-seq)-based identification and characterization were conducted on five pairs of lung adenocarcinoma tumors and adjacent nontumor tissues. Before our previous Chromosome-Centric Human Proteome Project (C-HPP) special issue, there were 170 remaining missing proteins on Chr 9 (neXtProt 2013.09.26 rel.); 133 remain at present (neXtProt 2015.04.28 rel.). In the proteomics study, we found two missing protein candidates that require follow-up work and one unrevealed protein across all chromosomes. RNA-seq analysis detected RNA expression for four nonsynonymous (NS) single nucleotide polymorphisms (SNPs) (in CDH17, HIST1H1T, SAPCD2, and ZNF695) and three synonymous SNPs (in CDH17, CST1, and HNF1A) in all five tumor tissues but not in any of the adjacent normal tissues. By constructing a cancer patient sample-specific protein database based on individual RNA-seq data and by searching the proteomics data from the same sample, we identified four missense mutations in four genes (LTF, HDLBP, TF, and HBD). Two of these mutations were found in tumor samples but not in paired normal tissues. In summary, our proteogenomic study of human primary lung tumor tissues detected additional and revealed novel missense mutations and synonymous SNP signatures, some of which are specific to lung cancers. Data from mass spectrometry have been deposited in the ProteomeXchange with the identifier PXD002523. PMID:26584007

  11. A selective genotyping approach identifies single nucleotide polymorphisms in porcine chromosome 2 genes associated with production and carcass traits in Italian heavy pigs

    OpenAIRE

    Vincenzo Russo; Luca Buttazzoni; Camilla Speroni; Emilio Scotti; Luca Fontanesi

    2011-01-01

    Several studies have shown that porcine chromosome 2 (SSC2) harbors important quantitative trait loci (QTL) for production traits. In particular, an imprinted QTL for muscle mass production is determined by a mutation in the IGF2 gene (intron3-g.3072G>A). We recently identified and analysed single nucleotide polymorphisms (SNPs) in genes (cathepsin D, CTSD g.70G>A; cathepsin F, CTSF g.22G>C; lactate dehydrogenase A, LDHA g.46G>T) localized on SSC2 (including the IGF2 intron3-g.3072G>A SNP) sh...

  12. Chromosomal replicons of higher plants

    Energy Technology Data Exchange (ETDEWEB)

    Van' t Hof, J.

    1987-03-16

    This brief discussion of replicons of higher plants offers a glimpse into the properties of chromosomal DNA replication. It gives evidence that the S phase of unrelated plant species is comprised of temporally ordered replicon families that increase in number with genome size. This orderly process, which assures a normal inheritance of genetic material to recipient daughter cells, is maintained at the level of replicon clusters by two mutually exclusive mechanisms, one involving the rate at which single replicons replicate their allotment of DNA, and another by means of the tempo-pause. The same two mechanisms are used by cells to alter the pattern of chromosomal DNA replication just prior to and during normal development. Both mechanisms are genetically determined and produce genetic effects when disturbed of disrupted by additional non-conforming DNAs. Further insight into how these two mechanisms operate requires more molecular information about the nature of replicons and the factors that govern when a replicon family replicates. Plant material is a rich and ideal source for this information just awaiting exploitation. 63 refs.

  13. Increased chromosome radiosensitivity during pregnancy

    International Nuclear Information System (INIS)

    It was necessary to consider the risks of exposure of pregnant women, not only in relation to the child, but also in relation to their own hypersensitivity. We have demonstrated that pregnancy increases radiosensitivity of chromosome in the mouse at the end of gestation. This is of importance since it may have implications on radioprotection of pregnant women and give experimental guidelines to the problems of hypersensitivity to drugs and cancer aggravation during pregnancy. Blood obtained from women at various times of pregnancy was exposed to ionizing radiations. By comparison to non-pregnant women, an increase in chromosome breakage was observed in metaphases from lymphocytes, after short-term culture in the presence of the serum of the same donor. Immediately after delivery, this increase in radiosensitivity disappeared. In a prospective study, serial analyses showed a very strong correlation between the amount of pregnancy hormones, progesterone in particular, and the increase in radiosensitivity. Pregnant women may have an increased sensitivity to ionizing radiation during the second half of their pregnancy. This study provides the first evidence in human that radiosensitivity may vary in relation to physiological conditions

  14. Retrospective dosimetry by chromosomal analysis

    International Nuclear Information System (INIS)

    The joint EU/CIS project ECP-6, was set up to examine whether cytogenetic dosimetry is possible for persons irradiated years previously at Chernobyl. The paper describes the possibility of achieving this by the examination of blood lymphocytes for unstable and stable chromosome aberrations; dicentrics and translocations. Emphasis was placed on the relatively new fluorescence in situ hybridization (FISH) method for rapid screening for stable translocations. In a collaborative experiment in vitro dose response calibration curves for dicentrics and FISH were produced with gamma radiation over the range 0-1.0 Gy. A pilot study of about 60 liquidators with registered doses ranging from 0-300 mSv was undertaken to determine whether the chromosomal methods may verify the recorded doses. It was concluded that the dicentric is no longer valid as a measured endpoint. Translocations may be used to verify early dosimetry carried out on highly irradiated persons. For the vast majority of lesser exposed subjects FISH is impractical as an individual dosimeter; it may have some value for comparing groups of subjects

  15. Chromosomal instability determines taxane response.

    Science.gov (United States)

    Swanton, Charles; Nicke, Barbara; Schuett, Marion; Eklund, Aron C; Ng, Charlotte; Li, Qiyuan; Hardcastle, Thomas; Lee, Alvin; Roy, Rajat; East, Philip; Kschischo, Maik; Endesfelder, David; Wylie, Paul; Kim, Se Nyun; Chen, Jie-Guang; Howell, Michael; Ried, Thomas; Habermann, Jens K; Auer, Gert; Brenton, James D; Szallasi, Zoltan; Downward, Julian

    2009-05-26

    Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting chromosomal instability (CIN). Silencing 22/50 of these genes, many of which are involved in DNA repair, caused cancer cell death, suggesting that these genes are involved in the survival of aneuploid cells. Overexpression of these "CIN-survival" genes is associated with poor outcome in estrogen receptor-positive breast cancer and occurs frequently in basal-like and Her2-positive cases. In diploid cells, but not in chromosomally unstable cells, paclitaxel causes repression of CIN-survival genes, followed by cell death. In the OV01 ovarian cancer clinical trial, a high level of CIN was associated with taxane resistance but carboplatin sensitivity, indicating that CIN may determine MTS response in vivo. Thus, pretherapeutic assessment of CIN may optimize treatment stratification and clinical trial design using these agents. PMID:19458043

  16. Chromosomal replicons of higher plants

    International Nuclear Information System (INIS)

    This brief discussion of replicons of higher plants offers a glimpse into the properties of chromosomal DNA replication. It gives evidence that the S phase of unrelated plant species is comprised of temporally ordered replicon families that increase in number with genome size. This orderly process, which assures a normal inheritance of genetic material to recipient daughter cells, is maintained at the level of replicon clusters by two mutually exclusive mechanisms, one involving the rate at which single replicons replicate their allotment of DNA, and another by means of the tempo-pause. The same two mechanisms are used by cells to alter the pattern of chromosomal DNA replication just prior to and during normal development. Both mechanisms are genetically determined and produce genetic effects when disturbed of disrupted by additional non-conforming DNAs. Further insight into how these two mechanisms operate requires more molecular information about the nature of replicons and the factors that govern when a replicon family replicates. Plant material is a rich and ideal source for this information just awaiting exploitation. 63 refs

  17. The X chromosome of monotremes shares a highly conserved region with the eutherian and marsupial X chromosomes despite the absence of X chromosome inactivation

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J.M.; Spencer, J.A.; Graves, J.A.M. (La Trobe Univ., Bundoora, Victoria (Australia)); Riggs, A.D. (Beckman Inst., Duarte, CA (USA))

    1990-09-01

    Eight genes, located on the long arm of the human X chromosome and present on the marsupial X chromosome, were mapped by in situ hybridization to the chromosomes of the platypus Ornithorhynchus anatinus, one of the three species of monotreme mammals. All were located on the X chromosome. The authors conclude that the long arm of the human X chromosome represents a highly conserved region that formed part of the X chromosome in a mammalian ancestor at least 150 million years ago. Since three of these genes are located on the long arm of the platypus X chromosome, which is G-band homologous to the Y chromosome and apparently exempt from X chromosome inactivation, the conservation of this region has evidently not depended on isolation by X-Y chromosome differentiation and X chromosome inactivation.

  18. Candidate adaptive genes associated with lineage divergence: identifying SNPs via next-generation targeted resequencing in mule deer (Odocoileus hemionus).

    Science.gov (United States)

    Powell, John H; Amish, Stephen J; Haynes, Gwilym D; Luikart, Gordon; Latch, Emily K

    2016-09-01

    Mule deer (Odocoileus hemionus) are an excellent nonmodel species for empirically testing hypotheses in landscape and population genomics due to their large population sizes (low genetic drift), relatively continuous distribution, diversity of occupied habitats and phenotypic variation. Because few genomic resources are currently available for this species, we used exon data from a cattle (Bos taurus) reference genome to direct targeted resequencing of 5935 genes in mule deer. We sequenced approximately 3.75 Mbp at minimum 20X coverage in each of the seven mule deer, identifying 23 204 single nucleotide polymorphisms (SNPs) within, or adjacent to, 6886 exons in 3559 genes. We found 91 SNP loci (from 69 genes) with putatively fixed allele frequency differences between the two major lineages of mule deer (mule deer and black-tailed deer), and our estimate of mean genetic divergence (genome-wide FST  = 0.123) between these lineages was consistent with previous findings using microsatellite loci. We detected an over-representation of gamete generation and amino acid transport genes among the genes with SNPs exhibiting potentially fixed allele frequency differences between lineages. This targeted resequencing approach using exon capture techniques has identified a suite of loci that can be used in future research to investigate the genomic basis of adaptation and differentiation between black-tailed deer and mule deer. This study also highlights techniques (and an exon capture array) that will facilitate population genomic research in other cervids and nonmodel organisms. PMID:27438092

  19. Association of tag SNPs of GPx-3 with essential hypertension in rural Han Chinese in Fuxin, Liaoning, China

    Institute of Scientific and Technical Information of China (English)

    HAO Ying; LI Hong; SUN Ying-xian; WU Bao-gang; SHI Jin; CHEN Yan-li; SUN Zhao-qing; ZHENG Li-qiang; ZHANG Xin-gang; GENG Ning; LI Tie-jun

    2011-01-01

    Background Genetic mechanisms contribute to blood pressure regulation. This study investigated whether glutathione peroxidase (GPx-3) tag single nucleotide polymorphisms (SNPs) are associated with hypertension in the rural areas of Fuxin county, Liaoning province, China.Methods Indigenous Fuxin Han people participated, 523 unrelated hypertensives and 547 controls were recruited. All tag SNPs of GPx-3 gene were selected. We estimated SNP allele frequency in DNA pools with pyrosequencing.Results Before Bonferroni correction, C allele frequency for rs8177417 was significantly higher in hypertensives than those in controls (23.4% vs. 19.3%, P=0.014); T allele frequency for rs3828599 was significantly lower in hypertensives than those in controls (35.6% vs. 40.8%,P=0.009). However, when a Bonferroni correction for multiple testing was applied, only the polymorphisms rs3828599 of GPx-3 gene was associated with hypertension (P=0.045, OR: 0.833, 95%CI: 0.695-0.998).Conclusion The polymorphism of rs3828599 of GPx-3 gene might be associated with hypertension in rural Han Chinese from Fuxin, Liaoning.

  20. Chromosomal painting and ZW sex chromosomes differentiation in Characidium (Characiformes, Crenuchidae

    Directory of Open Access Journals (Sweden)

    Artoni Roberto F

    2011-07-01

    Full Text Available Abstract Background The Characidium (a Neotropical fish group have a conserved diploid number (2n = 50, but show remarkable differences among species and populations in relation to sex chromosome systems and location of nucleolus organizer regions (NOR. In this study, we isolated a W-specific probe for the Characidium and characterized six Characidium species/populations using cytogenetic procedures. We analyzed the origin and differentiation of sex and NOR-bearing chromosomes by chromosome painting in populations of Characidium to reveal their evolution, phylogeny, and biogeography. Results A W-specific probe for efficient chromosome painting was isolated by microdissection and degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR amplification of W chromosomes from C. gomesi. The W probe generated weak signals dispersed on the proto sex chromosomes in C. zebra, dispersed signals in both W and Z chromosomes in C. lauroi and, in C. gomesi populations revealed a proximal site on the long arms of the Z chromosome and the entire W chromosome. All populations showed small terminal W probe sites in some autosomes. The 18S rDNA revealed distinctive patterns for each analyzed species/population with regard to proto sex chromosome, sex chromosome pair, and autosome location. Conclusions The results from dual-color fluorescence in situ hybridization (dual-color FISH using W and 18S rDNA probes allowed us to infer the putative evolutionary pathways for the differentiation of sex chromosomes and NORs, from structural rearrangements in a sex proto-chromosome, followed by gene erosion and heterochromatin amplification, morphological differentiation of the sex chromosomal pair, and NOR transposition, giving rise to the distinctive patterns observed among species/populations of Characidium. Biogeographic isolation and differentiation of sex chromosomes seem to have played a major role in the speciation process in this group of fish.

  1. Chromosomal painting and ZW sex chromosomes differentiation in Characidium (Characiformes, Crenuchidae)

    Science.gov (United States)

    2011-01-01

    Background The Characidium (a Neotropical fish group) have a conserved diploid number (2n = 50), but show remarkable differences among species and populations in relation to sex chromosome systems and location of nucleolus organizer regions (NOR). In this study, we isolated a W-specific probe for the Characidium and characterized six Characidium species/populations using cytogenetic procedures. We analyzed the origin and differentiation of sex and NOR-bearing chromosomes by chromosome painting in populations of Characidium to reveal their evolution, phylogeny, and biogeography. Results A W-specific probe for efficient chromosome painting was isolated by microdissection and degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR) amplification of W chromosomes from C. gomesi. The W probe generated weak signals dispersed on the proto sex chromosomes in C. zebra, dispersed signals in both W and Z chromosomes in C. lauroi and, in C. gomesi populations revealed a proximal site on the long arms of the Z chromosome and the entire W chromosome. All populations showed small terminal W probe sites in some autosomes. The 18S rDNA revealed distinctive patterns for each analyzed species/population with regard to proto sex chromosome, sex chromosome pair, and autosome location. Conclusions The results from dual-color fluorescence in situ hybridization (dual-color FISH) using W and 18S rDNA probes allowed us to infer the putative evolutionary pathways for the differentiation of sex chromosomes and NORs, from structural rearrangements in a sex proto-chromosome, followed by gene erosion and heterochromatin amplification, morphological differentiation of the sex chromosomal pair, and NOR transposition, giving rise to the distinctive patterns observed among species/populations of Characidium. Biogeographic isolation and differentiation of sex chromosomes seem to have played a major role in the speciation process in this group of fish. PMID:21787398

  2. Sequencing and association analysis of the type 1 diabetes – linked region on chromosome 10p12-q11

    Directory of Open Access Journals (Sweden)

    Barratt Bryan J

    2007-05-01

    Full Text Available Abstract Background In an effort to locate susceptibility genes for type 1 diabetes (T1D several genome-wide linkage scans have been undertaken. A chromosomal region designated IDDM10 retained genome-wide significance in a combined analysis of the main linkage scans. Here, we studied sequence polymorphisms in 23 Mb on chromosome 10p12-q11, including the putative IDDM10 region, to identify genes associated with T1D. Results Initially, we resequenced the functional candidate genes, CREM and SDF1, located in this region, genotyped 13 tag single nucleotide polymorphisms (SNPs and found no association with T1D. We then undertook analysis of the whole 23 Mb region. We constructed and sequenced a contig tile path from two bacterial artificial clone libraries. By comparison with a clone library from an unrelated person used in the Human Genome Project, we identified 12,058 SNPs. We genotyped 303 SNPs and 25 polymorphic microsatellite markers in 765 multiplex T1D families and followed up 22 associated polymorphisms in up to 2,857 families. We found nominal evidence of association in six loci (P = 0.05 – 0.0026, located near the PAPD1 gene. Therefore, we resequenced 38.8 kb in this region, found 147 SNPs and genotyped 84 of them in the T1D families. We also tested 13 polymorphisms in the PAPD1 gene and in five other loci in 1,612 T1D patients and 1,828 controls from the UK. Overall, only the D10S193 microsatellite marker located 28 kb downstream of PAPD1 showed nominal evidence of association in both T1D families and in the case-control sample (P = 0.037 and 0.03, respectively. Conclusion We conclude that polymorphisms in the CREM and SDF1 genes have no major effect on T1D. The weak T1D association that we detected in the association scan near the PAPD1 gene may be either false or due to a small genuine effect, and cannot explain linkage at the IDDM10 region.

  3. Non-disjunction of chromosome 13

    DEFF Research Database (Denmark)

    Bugge, Merete; Collins, Andrew; Hertz, Jens Michael;

    2007-01-01

    recombination in both maternal MI and MII errors and the former is associated with a significant number of tetrads (33%) that are nullichiasmate, which do not appear to be a feature of normal chromosome 13 meiosis. This study supports the evidence for subtle chromosome-specific influences on the mechanisms that...

  4. Chromosome number9 specific repetitive DNA sequence

    International Nuclear Information System (INIS)

    Human repetitive DNA libraries have been constructed and various recombinant DNA clones isolated that are likely candidates for chromosome specific sequences. The first clone tested (pHuR 98; plasmid human repeat 98) was biotinylated and hybridized to human chromosomes in situ. The hybridized recombinant probe was detected with fluoresceinated avidin, and chromosomes were counter-stained with either propidium iodide or distamycin-DAPI. Specific hybridization to chromosome band 9q1 was obtained. The localization was confirmed by hybridizing radiolabeled pHuR 98 DNA to human chromosomes sorted by flow cytometry. Various methods, including orthogonal field pulsed gel electrophoresis analysis indicate that 75 kilobase blocks of this sequence are interspersed with other repetitive DNA sequences in this chromosome band. This study is the first to report a human repetitive DNA sequence uniquely localized to a specific chromosome. This clone provides an easily detected and highly specific chromosomal marker for molecular cytogenetic analyses in numerous basic research and clinical studies

  5. Chromosomal characterization of Pseudonannolene strinatii (Spirostreptida, Pseudonannolenidae

    Directory of Open Access Journals (Sweden)

    Kleber Agari Campos

    2004-03-01

    Full Text Available The chromosomes of the cave millipede Pseudonannolene strinatii Mauriès, 1974 were investigated. The diploid chromosome number was found to be 2n=16, XX/XY; the C-banding technique revealed a large amount of heterochromatin while the silver staining technique (Ag-NOR evidenced the presence of heteromorphism of the NORs in some cells.

  6. Chromosomal Aneuploidies and Early Embryonic Developmental Arrest

    Directory of Open Access Journals (Sweden)

    Maria Maurer

    2015-07-01

    Full Text Available Background: Selecting the best embryo for transfer, with the highest chance of achieving a vital pregnancy, is a major goal in current in vitro fertilization (IVF technology. The high rate of embryonic developmental arrest during IVF treatment is one of the limitations in achieving this goal. Chromosomal abnormalities are possibly linked with chromosomal arrest and selection against abnormal fertilization products. The objective of this study was to evaluate the frequency and type of chromosomal abnormalities in preimplantation embryos with developmental arrest. Materials and Methods: This cohort study included blastomeres of embryos with early developmental arrest that were biopsied and analyzed by fluorescence in-situ hybridization (FISH with probes for chromosomes 13, 16, 18, 21 and 22. Forty-five couples undergoing IVF treatment were included, and 119 arrested embryos were biopsied. All probes were obtained from the Kinderwunsch Zentrum, Linz, Austria, between August 2009 and August 2011. Results: Of these embryos, 31.6% were normal for all chromosomes tested, and 68.4% were abnormal. Eleven embryos were uniformly aneuploid, 20 were polyploid, 3 were haploid, 11 displayed mosaicism and 22 embryos exhibited chaotic chromosomal complement. Conclusion: Nearly 70% of arrested embryos exhibit chromosomal errors, making chromosomal abnormalities a major cause of embryonic arrest and may be a further explanation for the high developmental failure rates during culture of the embryos in the IVF setting.

  7. Mechanisms of Chromosome Number Evolution in Yeast

    Science.gov (United States)

    Gordon, Jonathan L.; Byrne, Kevin P.; Wolfe, Kenneth H.

    2011-01-01

    The whole-genome duplication (WGD) that occurred during yeast evolution changed the basal number of chromosomes from 8 to 16. However, the number of chromosomes in post-WGD species now ranges between 10 and 16, and the number in non-WGD species (Zygosaccharomyces, Kluyveromyces, Lachancea, and Ashbya) ranges between 6 and 8. To study the mechanism by which chromosome number changes, we traced the ancestry of centromeres and telomeres in each species. We observe only two mechanisms by which the number of chromosomes has decreased, as indicated by the loss of a centromere. The most frequent mechanism, seen 8 times, is telomere-to-telomere fusion between two chromosomes with the concomitant death of one centromere. The other mechanism, seen once, involves the breakage of a chromosome at its centromere, followed by the fusion of the two arms to the telomeres of two other chromosomes. The only mechanism by which chromosome number has increased in these species is WGD. Translocations and inversions have cycled telomere locations, internalizing some previously telomeric genes and creating novel telomeric locations. Comparison of centromere structures shows that the length of the CDEII region is variable between species but uniform within species. We trace the complete rearrangement history of the Lachancea kluyveri genome since its common ancestor with Saccharomyces and propose that its exceptionally low level of rearrangement is a consequence of the loss of the non-homologous end joining (NHEJ) DNA repair pathway in this species. PMID:21811419

  8. Genomic Dark Matter Illuminated: Anopheles Y Chromosomes.

    Science.gov (United States)

    Redmond, Seth N; Neafsey, Daniel E

    2016-08-01

    Hall et al. have strategically used long-read sequencing technology to characterize the structure and highly repetitive content of the Y chromosome in Anopheles malaria mosquitoes. Their work confirms that this important but elusive heterochromatic sex chromosome is evolving extremely rapidly and harbors a remarkably small number of genes. PMID:27263828

  9. Physical map of the Bacillus cereus chromosome.

    OpenAIRE

    Kolstø, A B; Grønstad, A; Oppegaard, H

    1990-01-01

    A physical map of the Bacillus cereus chromosome has been constructed by aligning 11 NotI fragments, ranging in size from 200 to 1,300 kilobases. The size of the chromosome is about 5.7 megabases. This is the first Bacillus genome of which a complete physical map has been described.

  10. Compositions for chromosome-specific staining

    Science.gov (United States)

    Gray, Joe W.; Pinkel, Daniel

    1998-01-01

    Methods and compositions for staining based upon nucleic acid sequence that employ nucleic acid probes are provided. Said methods produce staining patterns that can be tailored for specific cytogenetic analyses. Said probes are appropriate for in situ hybridization and stain both interphase and metaphase chromosomal material with reliable signals. The nucleic acid probes are typically of a complexity greater than 50 kb, the complexity depending upon the cytogenetic application. Methods are provided to disable the hybridization capacity of shared, high copy repetitive sequences and/or remove such sequences to provide for useful contrast. Still further methods are provided to produce chromosome-specific staining reagents which are made specific to the targeted chromosomal material, which can be one or more whole chromosomes, one or more regions on one or more chromosomes, subsets of chromosomes and/or the entire genome. Probes and test kits are provided for use in tumor cytogenetics, in the detection of disease related loci, in analysis of structural abnormalities, such as translocations, and for biological dosimetry. Further, methods and prenatal test kits are provided to stain targeted chromosomal material of fetal cells, including fetal cells obtained from maternal blood. Still further, the invention provides for automated means to detect and analyse chromosomal abnormalities.

  11. Construction of High Density Sweet Cherry (Prunus avium L.) Linkage Maps Using Microsatellite Markers and SNPs Detected by Genotyping-by-Sequencing (GBS).

    Science.gov (United States)

    Guajardo, Verónica; Solís, Simón; Sagredo, Boris; Gainza, Felipe; Muñoz, Carlos; Gasic, Ksenija; Hinrichsen, Patricio

    2015-01-01

    Linkage maps are valuable tools in genetic and genomic studies. For sweet cherry, linkage maps have been constructed using mainly microsatellite markers (SSRs) and, recently, using single nucleotide polymorphism markers (SNPs) from a cherry 6K SNP array. Genotyping-by-sequencing (GBS), a new methodology based on high-throughput sequencing, holds great promise for identification of high number of SNPs and construction of high density linkage maps. In this study, GBS was used to identify SNPs from an intra-specific sweet cherry cross. A total of 8,476 high quality SNPs were selected for mapping. The physical position for each SNP was determined using the peach genome, Peach v1.0, as reference, and a homogeneous distribution of markers along the eight peach scaffolds was obtained. On average, 65.6% of the SNPs were present in genic regions and 49.8% were located in exonic regions. In addition to the SNPs, a group of SSRs was also used for construction of linkage maps. Parental and consensus high density maps were constructed by genotyping 166 siblings from a 'Rainier' x 'Rivedel' (Ra x Ri) cross. Using Ra x Ri population, 462, 489 and 985 markers were mapped into eight linkage groups in 'Rainier', 'Rivedel' and the Ra x Ri map, respectively, with 80% of mapped SNPs located in genic regions. Obtained maps spanned 549.5, 582.6 and 731.3 cM for 'Rainier', 'Rivedel' and consensus maps, respectively, with an average distance of 1.2 cM between adjacent markers for both 'Rainier' and 'Rivedel' maps and of 0.7 cM for Ra x Ri map. High synteny and co-linearity was observed between obtained maps and with Peach v1.0. These new high density linkage maps provide valuable information on the sweet cherry genome, and serve as the basis for identification of QTLs and genes relevant for the breeding of the species. PMID:26011256

  12. Characterization of novel and uncharacterized p53 SNPs in the Chinese population--intron 2 SNP co-segregates with the common codon 72 polymorphism.

    Directory of Open Access Journals (Sweden)

    Beng Hooi Phang

    Full Text Available Multiple single nucleotide polymorphisms (SNPs have been identified in the tumor suppressor gene p53, though the relevance of many of them is unclear. Some of them are also differentially distributed in various ethnic populations, suggesting selective functionality. We have therefore sequenced all exons and flanking regions of p53 from the Singaporean Chinese population and report here the characterization of some novel and uncharacterized SNPs - four in intron 1 (nucleotide positions 8759/10361/10506/11130, three in intron 3 (11968/11969/11974 and two in the 3'UTR (19168/19514. Allelic frequencies were determined for all these and some known SNPs, and were compared in a limited scale to leukemia and lung cancer patient samples. Intron 2 (11827 and 7 (14181/14201 SNPs were found to have a high minor allele frequency of between 26-47%, in contrast to the lower frequencies found in the US population, but similar in trend to the codon 72 polymorphism (SNP12139 that shows a distribution pattern correlative with latitude. Several of the SNPs were linked, such as those in introns 1, 3 and 7. Most interestingly, we noticed the co-segregation of the intron 2 and the codon 72 SNPs, the latter which has been shown to be expressed in an allele-specific manner, suggesting possible regulatory cross-talk. Association analysis indicated that the T/G alleles in both the co-segregating intron 7 SNPs and a 4tagSNP haplotype was strongly associated increased susceptibility to lung cancer in non-smoker females [OR: 1.97 (1.32, 3.394]. These data together demonstrate high SNP diversity in p53 gene between different populations, highlighting ethnicity-based differences, and their association with cancer risk.

  13. Family-Based Multi-SNP X Chromosome Analysis Using Parent Information.

    Science.gov (United States)

    Wise, Alison S; Shi, Min; Weinberg, Clarice R

    2016-01-01

    We propose a method for association analysis of haplotypes on the X chromosome that offers both improved power and robustness to population stratification in studies of affected offspring and their parents if all three have been genotyped. The method makes use of assumed parental haplotype exchangeability (PHE), a weaker assumption than Hardy-Weinberg equilibrium (HWE). PHE requires that in the source population, of the three X chromosome haplotypes carried by the two parents, each is equally likely to be carried by the father. We propose a pseudo-sibling approach that exploits that exchangeability assumption. Our method extends the single-SNP PIX-LRT method to multiple SNPs in a high linkage block. We describe methods for testing the PHE assumption and also for determining how apparent violations can be distinguished from true fetal effects or maternally-mediated effects. We show results of simulations that demonstrate nominal type I error rate and good power. The methods are then applied to dbGaP data on the birth defect oral cleft, using both Asian and Caucasian families with cleft. PMID:26941777

  14. Genetic data from Y chromosome STR and SNP loci in Ukrainian population.

    Science.gov (United States)

    Mielnik-Sikorska, Marta; Daca, Patrycja; Woźniak, Marcin; Malyarchuk, Boris A; Bednarek, Jarosław; Dobosz, Tadeusz; Grzybowski, Tomasz

    2013-01-01

    We have tested a sample of 154 unrelated males from Lviv region (Ukraine) for 11 Y-chromosomal single nucleotide polymorphisms (SNPs) and 17 Y-chromosomal STR loci (DYS19, DYS385a, DYS385b, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, YGATA_H4.1). Haplotype and haplogroup diversity values were calculated for the population under study. Genetic distances (R(ST)) to 9 other Slavic populations were calculated based on 12 Y-STR loci. Haplotype frequencies and MDS plots were constructed based on genetic distances. Haplogroup frequency patterns revealed in Ukraine are similar to those characteristic of other European populations. However, it also allowed for identification a specific genetic component in Ukrainian sample which seems to originate from areas dwelled by Western Slavs, i.e. subhaplogroup R1a1a7, at frequency of 13.65%. Analysis of R(ST) distances and AMOVA revealed high level of heterogeneity between Slavic populations inhabiting the south and north part of Europe, determined geographically rather than by linguistic factors. It has also been found a closer similarity (in the values of R(ST)) between Ukrainian and Slovak populations than between Ukrainians and other Slavic population samples. PMID:22673612

  15. Mapping of human chromosomal regions related to neoplasia: evidence from chromosomes 1 and 17

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, J.D.

    1977-12-01

    In clonal aberrations leading to an excess or partial excess of chromosome I, trisomy for bands 1q25-1q32 was noted in the myeloid cells from all of 34 patients who had various disorders such as acute leukemia, polycythemia vera, and myelofibrosis. This was not the result of a particularly fragile site in that region of the chromosome because the break points in reciprocal translocations that involve it occurred almost exclusively in the short arm. Two consistent rearrangements that have been observed in chromosome 17 produced either duplication of the entire long arm or a translocation of the distal portion of the long arm to chromosome 15. The nonrandom chromosomal changes found in hematologic disorders can now be correlated with the gene loci on these chromosomes or chromosomal segments. Seventy-five genes related to various metabolic enzymes have been mapped; it may be significant that chromosomes carrying gene loci related to nucleic acid metabolism are more frequently involved in hematologic disorders (and other malignancies as well) than are gene loci related to intermediary or carbohydrate metabolism. Furthermore, the known virus-human chromosome associations are closely correlated with the chromosomes affected in hematologic disorders. If one of the effects of carcinogens (including viruses) is to activate genes that regulate host cell DNA synthesis, and if translocations or duplications of specific chromosomal segments produce the same effect, then either of these mechanisms might provide the affected cell with a proliferative advantage.

  16. Review of the Y chromosome and hypertension

    Directory of Open Access Journals (Sweden)

    D. Ely

    2000-06-01

    Full Text Available The Y chromosome from spontaneously hypertensive rats (SHR has a locus that raises blood pressure 20-25 mmHg. Associated with the SHR Y chromosome effect is a 4-week earlier pubertal rise of testosterone and dependence upon the androgen receptor for the full blood pressure effect. Several indices of enhanced sympathetic nervous system (SNS activity are also associated with the SHR Y chromosome. Blockade of SNS outflow reduced the blood pressure effect. Salt sensitivity was increased by the Y chromosome as was salt appetite which was SNS dependent. A strong correlation (r = 0.57, P<0.001 was demonstrable between plasma testosterone and angiotensin II. Coronary collagen increased with blood pressure and the presence of the SHR Y chromosome. A promising candidate gene for the Y effect is the Sry locus (testis determining factor, a transcription factor which may also have other functions.

  17. Genetic conflict and sex chromosome evolution

    Science.gov (United States)

    Meiklejohn, Colin D; Tao, Yun

    2009-01-01

    Chromosomal sex determination systems create the opportunity for the evolution of selfish genetic elements that increase the transmission of one sex chromosome at the expense of its homolog. Because such selfish elements on sex chromosomes can reduce fertility and distort the sex ratio of progeny, unlinked suppressors are expected to evolve, bringing different regions of the genome into conflict over the meiotic transmission of the sex chromosomes. Here we argue that recurrent genetic conflict over sex chromosome transmission is an important evolutionary force that has shaped a wide range of seemingly disparate phenomena including the epigenetic regulation of genes expressed in the germline, the distribution of genes in the genome, and the evolution of hybrid sterility between species. PMID:19931208

  18. Advances in understanding paternally transmitted Chromosomal Abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Marchetti, F; Sloter, E; Wyrobek, A J

    2001-03-01

    Multicolor FISH has been adapted for detecting the major types of chromosomal abnormalities in human sperm including aneuploidies for clinically-relevant chromosomes, chromosomal aberrations including breaks and rearrangements, and other numerical abnormalities. The various sperm FISH assays have been used to evaluate healthy men, men of advanced age, and men who have received mutagenic cancer therapy. The mouse has also been used as a model to investigate the mechanism of paternally transmitted genetic damage. Sperm FISH for the mouse has been used to detect chromosomally abnormal mouse sperm, while the PAINT/DAPI analysis of mouse zygotes has been used to evaluate the types of chromosomal defects that can be paternally transmitted to the embryo and their effects on embryonic development.

  19. New Y chromosomes and early stages of sex chromosome differentiation: sex determination in Megaselia

    Indian Academy of Sciences (India)

    Walther Traut

    2010-09-01

    The phorid fly Megaselia scalaris is a laboratory model for the turnover and early differentiation of sex chromosomes. Isolates from the field have an XY sex-determining mechanism with chromosome pair 2 acting as X and Y chromosomes. The sex chromosomes are homomorphic but display early signs of sex chromosome differentiation: a low level of molecular differences between X and Y. The male-determining function $(M)$, maps to the distal part of the Y chromosome’s short arm. In laboratory cultures, new Y chromosomes with no signs of a molecular differentiation arise at a low rate, probably by transposition of to these chromosomes. Downstream of the primary signal, the homologue of the Drosophila doublesex (dsx) is part of the sex-determining pathway while Sex-lethal (Sxl), though structurally conserved, is not.

  20. Y-chromosome evolution: emerging insights into processes of Y-chromosome degeneration.

    Science.gov (United States)

    Bachtrog, Doris

    2013-02-01

    The human Y chromosome is intriguing not only because it harbours the master-switch gene that determines gender but also because of its unusual evolutionary history. The Y chromosome evolved from an autosome, and its evolution has been characterized by massive gene decay. Recent whole-genome and transcriptome analyses of Y chromosomes in humans and other primates, in Drosophila species and in plants have shed light on the current gene content of the Y chromosome, its origins and its long-term fate. Furthermore, comparative analysis of young and old Y chromosomes has given further insights into the evolutionary and molecular forces triggering Y-chromosome degeneration and into the evolutionary destiny of the Y chromosome. PMID:23329112

  1. Novel gene acquisition on carnivore Y chromosomes.

    Directory of Open Access Journals (Sweden)

    2006-03-01

    Full Text Available Despite its importance in harboring genes critical for spermatogenesis and male-specific functions, the Y chromosome has been largely excluded as a priority in recent mammalian genome sequencing projects. Only the human and chimpanzee Y chromosomes have been well characterized at the sequence level. This is primarily due to the presumed low overall gene content and highly repetitive nature of the Y chromosome and the ensuing difficulties using a shotgun sequence approach for assembly. Here we used direct cDNA selection to isolate and evaluate the extent of novel Y chromosome gene acquisition in the genome of the domestic cat, a species from a different mammalian superorder than human, chimpanzee, and mouse (currently being sequenced. We discovered four novel Y chromosome genes that do not have functional copies in the finished human male-specific region of the Y or on other mammalian Y chromosomes explored thus far. Two genes are derived from putative autosomal progenitors, and the other two have X chromosome homologs from different evolutionary strata. All four genes were shown to be multicopy and expressed predominantly or exclusively in testes, suggesting that their duplication and specialization for testis function were selected for because they enhance spermatogenesis. Two of these genes have testis-expressed, Y-borne copies in the dog genome as well. The absence of the four newly described genes on other characterized mammalian Y chromosomes demonstrates the gene novelty on this chromosome between mammalian orders, suggesting it harbors many lineage-specific genes that may go undetected by traditional comparative genomic approaches. Specific plans to identify the male-specific genes encoded in the Y chromosome of mammals should be a priority.

  2. Chromosome differentiation patterns during cichlid fish evolution

    Directory of Open Access Journals (Sweden)

    Nirchio Mauro

    2010-06-01

    Full Text Available Abstract Background Cichlid fishes have been the subject of increasing scientific interest because of their rapid adaptive radiation which has led to an extensive ecological diversity and their enormous importance to tropical and subtropical aquaculture. To increase our understanding of chromosome evolution among cichlid species, karyotypes of one Asian, 22 African, and 30 South American cichlid species were investigated, and chromosomal data of the family was reviewed. Results Although there is extensive variation in the karyotypes of cichlid fishes (from 2n = 32 to 2n = 60 chromosomes, the modal chromosome number for South American species was 2n = 48 and the modal number for the African ones was 2n = 44. The only Asian species analyzed, Etroplus maculatus, was observed to have 46 chromosomes. The presence of one or two macro B chromosomes was detected in two African species. The cytogenetic mapping of 18S ribosomal RNA (18S rRNA gene revealed a variable number of clusters among species varying from two to six. Conclusions The karyotype diversification of cichlids seems to have occurred through several chromosomal rearrangements involving fissions, fusions and inversions. It was possible to identify karyotype markers for the subfamilies Pseudocrenilabrinae (African and Cichlinae (American. The karyotype analyses did not clarify the phylogenetic relationship among the Cichlinae tribes. On the other hand, the two major groups of Pseudocrenilabrinae (tilapiine and haplochromine were clearly discriminated based on the characteristics of their karyotypes. The cytogenetic mapping of 18S ribosomal RNA (18S rRNA gene did not follow the chromosome diversification in the family. The dynamic evolution of the repeated units of rRNA genes generates patterns of chromosomal distribution that do not help follows the phylogenetic relationships among taxa. The presence of B chromosomes in cichlids is of particular interest because they may not be represented in

  3. A genome-wide association study identifies pancreatic cancer susceptibility loci on chromosomes 13q22.1, 1q32.1 and 5p15.33

    Science.gov (United States)

    Petersen, Gloria M.; Amundadottir, Laufey; Fuchs, Charles S.; Kraft, Peter; Stolzenberg-Solomon, Rachael Z.; Jacobs, Kevin B.; Arslan, Alan A.; Bueno-de-Mesquita, H. Bas; Gallinger, Steven; Gross, Myron; Helzlsouer, Kathy; Holly, Elizabeth A.; Jacobs, Eric J.; Klein, Alison P.; LaCroix, Andrea; Li, Donghui; Mandelson, Margaret T.; Olson, Sara H.; Risch, Harvey A.; Zheng, Wei; Albanes, Demetrius; Bamlet, William R.; Berg, Christine D.; Boutron-Ruault, Marie-Christine; Buring, Julie E.; Bracci, Paige M.; Canzian, Federico; Clipp, Sandra; Cotterchio, Michelle; de Andrade, Mariza; Duell, Eric J.; Gaziano, J. Michael; Giovannucci, Edward L.; Goggins, Michael; Hallmans, Göran; Hankinson, Susan E.; Hassan, Manal; Howard, Barbara; Hunter, David J.; Hutchinson, Amy; Jenab, Mazda; Kaaks, Rudolf; Kooperberg, Charles; Krogh, Vittorio; Kurtz, Robert C.; Lynch, Shannon M.; McWilliams, Robert R.; Mendelsohn, Julie B.; Michaud, Dominique S.; Parikh, Hemang; Patel, Alpa V.; Peeters, Petra H.M.; Rajkovic, Aleksandar; Riboli, Elio; Rodriguez, Laudina; Seminara, Daniela; Shu, Xiao-Ou; Thomas, Gilles; Tjønneland, Anne; Tobias, Geoffrey S.; Trichopoulos, Dimitrios; Van Den Eeden, Stephen K.; Virtamo, Jarmo; Wactawski-Wende, Jean; Wang, Zhaoming; Wolpin, Brian M.; Yu, Herbert; Yu, Kai; Zeleniuch-Jacquotte, Anne; Fraumeni, Joseph F.; Hoover, Robert N.; Hartge, Patricia; Chanock, Stephen J.

    2010-01-01

    We conducted a genome-wide association study (GWAS) of pancreatic cancer in 3,851 cases and 3,934 controls drawn from twelve prospective cohort studies and eight case-control studies. Based on a logistic regression model for genotype trend effect that was adjusted for study, age, sex, self-described ancestry and five principal components, we identified eight SNPs that map to three loci on chromosomes 13q22.1, 1q32.1 and 5p15.33. Two correlated SNPs, rs9543325 (P=3.27×10−11; per allele odds ratio, OR 1.26, 95% CI=1.18-1.35) and rs9564966 (P=5.86×10−8; per allele OR 1.21, 95% CI=1.13-1.30) map to a non-genic region on chromosome 13q22.1. Five SNPs on 1q32.1 map to NR5A2; the strongest signal was rs3790844 (P=2.45×10−10; per allele OR 0.77, 95% CI=0.71-0.84). A single SNP, rs401681 (P=3.66×10−7; per allele OR 1.19, 95% CI=1.11-1.27) maps to the CLPTM1L-TERT locus on 5p15.33, associated with multiple cancers. Our study has identified common susceptibility loci for pancreatic cancer that warrant follow-up studies. PMID:20101243

  4. Reduced Representation Libraries from DNA Pools Analysed with Next Generation Semiconductor Based-Sequencing to Identify SNPs in Extreme and Divergent Pigs for Back Fat Thickness

    Directory of Open Access Journals (Sweden)

    Samuele Bovo

    2015-01-01

    Full Text Available The aim of this study was to identify single nucleotide polymorphisms (SNPs that could be associated with back fat thickness (BFT in pigs. To achieve this goal, we evaluated the potential and limits of an experimental design that combined several methodologies. DNA samples from two groups of Italian Large White pigs with divergent estimating breeding value (EBV for BFT were separately pooled and sequenced, after preparation of reduced representation libraries (RRLs, on the Ion Torrent technology. Taking advantage from SNAPE for SNPs calling in sequenced DNA pools, 39,165 SNPs were identified; 1/4 of them were novel variants not reported in dbSNP. Combining sequencing data with Illumina PorcineSNP60 BeadChip genotyping results on the same animals, 661 genomic positions overlapped with a good approximation of minor allele frequency estimation. A total of 54 SNPs showing enriched alleles in one or in the other RRLs might be potential markers associated with BFT. Some of these SNPs were close to genes involved in obesity related phenotypes.

  5. Reduced Representation Libraries from DNA Pools Analysed with Next Generation Semiconductor Based-Sequencing to Identify SNPs in Extreme and Divergent Pigs for Back Fat Thickness

    Science.gov (United States)

    Bovo, Samuele; Bertolini, Francesca; Schiavo, Giuseppina; Mazzoni, Gianluca; Dall'Olio, Stefania; Fontanesi, Luca

    2015-01-01

    The aim of this study was to identify single nucleotide polymorphisms (SNPs) that could be associated with back fat thickness (BFT) in pigs. To achieve this goal, we evaluated the potential and limits of an experimental design that combined several methodologies. DNA samples from two groups of Italian Large White pigs with divergent estimating breeding value (EBV) for BFT were separately pooled and sequenced, after preparation of reduced representation libraries (RRLs), on the Ion Torrent technology. Taking advantage from SNAPE for SNPs calling in sequenced DNA pools, 39,165 SNPs were identified; 1/4 of them were novel variants not reported in dbSNP. Combining sequencing data with Illumina PorcineSNP60 BeadChip genotyping results on the same animals, 661 genomic positions overlapped with a good approximation of minor allele frequency estimation. A total of 54 SNPs showing enriched alleles in one or in the other RRLs might be potential markers associated with BFT. Some of these SNPs were close to genes involved in obesity related phenotypes. PMID:25821781

  6. First Comprehensive In Silico Analysis of the Functional and Structural Consequences of SNPs in Human GalNAc-T1 Gene

    Directory of Open Access Journals (Sweden)

    Hussein Sheikh Ali Mohamoud

    2014-01-01

    Full Text Available GalNAc-T1, a key candidate of GalNac-transferases genes family that is involved in mucin-type O-linked glycosylation pathway, is expressed in most biological tissues and cell types. Despite the reported association of GalNAc-T1 gene mutations with human disease susceptibility, the comprehensive computational analysis of coding, noncoding and regulatory SNPs, and their functional impacts on protein level, still remains unknown. Therefore, sequence- and structure-based computational tools were employed to screen the entire listed coding SNPs of GalNAc-T1 gene in order to identify and characterize them. Our concordant in silico analysis by SIFT, PolyPhen-2, PANTHER-cSNP, and SNPeffect tools, identified the potential nsSNPs (S143P, G258V, and Y414D variants from 18 nsSNPs of GalNAc-T1. Additionally, 2 regulatory SNPs (rs72964406 and #x26; rs34304568 were also identified in GalNAc-T1 by using FastSNP tool. Using multiple computational approaches, we have systematically classified the functional mutations in regulatory and coding regions that can modify expression and function of GalNAc-T1 enzyme. These genetic variants can further assist in better understanding the wide range of disease susceptibility associated with the mucin-based cell signalling and pathogenic binding, and may help to develop novel therapeutic elements for associated diseases.

  7. Chromosomal rearrangements in cattle and pigs revealed by chromosome microdissection and chromosome painting

    OpenAIRE

    Yerle Martine; Ducos Alain; Pinton Alain

    2003-01-01

    Abstract A pericentric inversion of chromosome 4 in a boar, as well as a case of (2q-;5p+) translocation mosaicism in a bull were analysed by chromosome painting using probes generated by conventional microdissection. For the porcine inversion, probes specific for p arms and q arms were produced and hybridised simultaneously on metaphases of a heterozygote carrier. In the case of the bovine translocation, two whole chromosome probes (chromosome 5, and derived chromosome 5) were elaborated and...

  8. Sex chromosome evolution: platypus gene mapping suggests that part of the human X chromosome was originally autosomal.

    OpenAIRE

    Watson, J M; Spencer, J. A.; Riggs, A D; Graves, J.A.

    1991-01-01

    To investigate the evolution of the mammalian sex chromosomes, we have compared the gene content of the X chromosomes in the mammalian groups most distantly related to man (marsupials and monotremes). Previous work established that genes on the long arm of the human X chromosome are conserved on the X chromosomes in all mammals, revealing that this region was part of an ancient mammalian X chromosome. However, we now report that several genes located on the short arm of the human X chromosome...

  9. Screening of Tag SNPs and prediction of their potential function in genetic studies of complex diseases%复杂性疾病遗传研究中Tag SNP的筛选及其潜在功能预测

    Institute of Scientific and Technical Information of China (English)

    朱益民; 许玉洋; 凌洁

    2011-01-01

    利用公共数据库筛选与复杂性疾病相关的单核苷酸多态性(single nucleotide polymorphism,SNP).运用FastSNP、SNP Function Prediction、F-SNP等多种SNP功能预测软件筛选有潜在功能的SNPs;通过HapMap等数据库筛选Tag SNP;综合比较各软件结果.以IGFBP 7基因为例,筛选转录因子结合位点SNPs 11个,内含子增强子31个,内含子增强子和转录因子结合位点4个,剪接位点1个,共47个SNPs.%We applied public databases of single nucleotide polymorphism (SNP) to screen complex disease-related SNPs and assessed the potential functions of selected SNPs through SNP function prediction software, including FastSNP, SNP Function Prediction, F-SNP. We selected Tag SNP in HapMap database and compared all results with above software. With above strategies we screened IGFBP7 gene and obtained total 47 SNPs, including 11 TFBS SNPs,31 intronic enhancer SNPs,4 intronic enhancer and TFBS SNPs and 1 splicing sites SNPs.

  10. Comprehensive gene-based association study of a chromosome 20 linked region implicates novel risk loci for depressive symptoms in psychotic illness.

    Directory of Open Access Journals (Sweden)

    T Bernard Bigdeli

    Full Text Available BACKGROUND: Prior genomewide scans of schizophrenia support evidence of linkage to regions of chromosome 20. However, association analyses have yet to provide support for any etiologically relevant variants. METHODS: We analyzed 2988 LD-tagging single nucleotide polymorphisms (SNPs in 327 genes on chromosome 20, to test for association with schizophrenia in 270 Irish high-density families (ISHDSF, N = 270 families, 1408 subjects. These SNPs were genotyped using an Illumina iSelect genotyping array which employs the Infinium assay. Given a previous report of novel linkage with chromosome 20p using latent classes of psychotic illness in this sample, association analysis was also conducted for each of five factor-derived scores based on the Operational Criteria Checklist for Psychotic Illness (delusions, hallucinations, mania, depression, and negative symptoms. Tests of association were conducted using the PDTPHASE and QPDTPHASE packages of UNPHASED. Empirical estimates of gene-wise significance were obtained by adaptive permutation of a the smallest observed P-value and b the threshold-truncated product of P-values for each locus. RESULTS: While no single variant was significant after LD-corrected Bonferroni-correction, our gene-dropping analyses identified loci which exceeded empirical significance criteria for both gene-based tests. Namely, R3HDML and C20orf39 are significantly associated with depressive symptoms of schizophrenia (P(emp<2×10⁻⁵ based on the minimum P-value and truncated-product methods, respectively. CONCLUSIONS: Using a gene-based approach to family-based association, R3HDML and C20orf39 were found to be significantly associated with clinical dimensions of schizophrenia. These findings demonstrate the efficacy of gene-based analysis and support previous evidence that chromosome 20 may harbor schizophrenia susceptibility or modifier loci.

  11. Nonrandom chromosomal changes in human malignant cells

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, J D

    1977-01-01

    The role of chromosomal changes in human malignant cells has been the subject of much debate. The observation of nonrandom chromosomal changes has become well recognized in chronic myelogenous leukemia, and more recently in acute myelogenous leukemia. In the present report, data are presented on the sites of duplication of chromosome No. 1 in hematologic disorders. Trisomy for region lq25 to lq32 was observed in every one of 34 patients whose cells showed duplication of some part of chromosome No. 1. Adjacent regions lq21 to lq25, and lq32 to lqter, also were trisomic in the majority of patients. Two patients had deletions, one of lq32 to qter, and the other, of lp32 to pter. The sites of chromosomal breaks leading to trisomy differ from those involved in balanced reciprocal translocations. Some of these sites are sometimes, but not always, vulnerable in constitutional chromosomal abnormalities. The nature of the proliferative advantage conferred on myeloid cells by these chromosomal changes is unknown.

  12. Chromosome number evolution in skippers (Lepidoptera, Hesperiidae).

    Science.gov (United States)

    Lukhtanov, Vladimir A

    2014-01-01

    Lepidoptera (butterflies and moths), as many other groups of animals and plants, simultaneously represent preservation of ancestral karyotype in the majority of families with a high degree of chromosome number instability in numerous independently evolved phylogenetic lineages. However, the pattern and trends of karyotype evolution in some Lepidoptera families are poorly studied. Here I provide a survey of chromosome numbers in skippers (family Hesperiidae) based on intensive search and analysis of published data. I demonstrate that the majority of skippers preserve the haploid chromosome number n=31 that seems to be an ancestral number for the Hesperiidae and the order Lepidoptera at whole. However, in the tribe Baorini the derived number n=16 is the most typical state which can be used as a (syn)apomorphic character in further phylogenetic investigations. Several groups of skippers display extreme chromosome number variations on within-species (e.g. the representatives of the genus Carcharodus Hübner, [1819]) and between-species (e.g. the genus Agathymus Freeman, 1959) levels. Thus, these groups can be used as model systems for future analysis of the phenomenon of chromosome instability. Interspecific chromosomal differences are also shown to be useful for discovering and describing new cryptic species of Hesperiidae representing in such a way a powerful tool in biodiversity research. Generally, the skipper butterflies promise to be an exciting group that will significantly contribute to the growing knowledge of patterns and processes of chromosome evolution. PMID:25610542

  13. Chromosome number evolution in skippers (Lepidoptera, Hesperiidae

    Directory of Open Access Journals (Sweden)

    Vladimir Lukhtanov

    2014-11-01

    Full Text Available Lepidoptera (butterflies and moths, as many other groups of animals and plants, simultaneously represent preservation of ancestral karyotype in the majority of families with a high degree of chromosome number instability in numerous independently evolved phylogenetic lineages. However, the pattern and trends of karyotype evolution in some Lepidoptera families are poorly studied. Here I provide a survey of chromosome numbers in skippers (family Hesperiidae based on intensive search and analysis of published data. I demonstrate that the majority of skippers preserve the haploid chromosome number n=31 that seems to be an ancestral number for the Hesperiidae and the order Lepidoptera at whole. However, in the tribe Baorini the derived number n=16 is the most typical state which can be used as a (synapomorphic character in further phylogenetic investigations. Several groups of skippers display extreme chromosome number variations on within-species (e.g. the representatives of the genus Carcharodus Hübner, [1819] and between-species (e.g. the genus Agathymus Freeman, 1959 levels. Thus, these groups can be used as model systems for future analysis of the phenomenon of chromosome instability. Interspecific chromosomal differences are also shown to be useful for discovering and describing new cryptic species of Hesperiidae representing in such a way a powerful tool in biodiversity research. Generally, the skipper butterflies promise to be an exciting group that will significantly contribute to the growing knowledge of patterns and processes of chromosome evolution.

  14. Group 3 chromosome bin maps of wheat and their relationship to rice chromosome 1.

    Science.gov (United States)

    Munkvold, J D; Greene, R A; Bermudez-Kandianis, C E; La Rota, C M; Edwards, H; Sorrells, S F; Dake, T; Benscher, D; Kantety, R; Linkiewicz, A M; Dubcovsky, J; Akhunov, E D; Dvorák, J; Miftahudin; Gustafson, J P; Pathan, M S; Nguyen, H T; Matthews, D E; Chao, S; Lazo, G R; Hummel, D D; Anderson, O D; Anderson, J A; Gonzalez-Hernandez, J L; Peng, J H; Lapitan, N; Qi, L L; Echalier, B; Gill, B S; Hossain, K G; Kalavacharla, V; Kianian, S F; Sandhu, D; Erayman, M; Gill, K S; McGuire, P E; Qualset, C O; Sorrells, M E

    2004-10-01

    The focus of this study was to analyze the content, distribution, and comparative genome relationships of 996 chromosome bin-mapped expressed sequence tags (ESTs) accounting for 2266 restriction fragments (loci) on the homoeologous group 3 chromosomes of hexaploid wheat (Triticum aestivum L.). Of these loci, 634, 884, and 748 were mapped on chromosomes 3A, 3B, and 3D, respectively. The individual chromosome bin maps revealed bins with a high density of mapped ESTs in the distal region and bins of low density in the proximal region of the chromosome arms, with the exception of 3DS and 3DL. These distributions were more localized on the higher-resolution group 3 consensus map with intermediate regions of high-mapped-EST density on both chromosome arms. Gene ontology (GO) classification of mapped ESTs was not significantly different for homoeologous group 3 chromosomes compared to the other groups. A combined analysis of the individual bin maps using 537 of the mapped ESTs revealed rearrangements between the group 3 chromosomes. Approximately 232 (44%) of the consensus mapped ESTs matched sequences on rice chromosome 1 and revealed large- and small-scale differences in gene order. Of the group 3 mapped EST unigenes approximately 21 and 32% matched the Arabidopsis coding regions and proteins, respectively, but no chromosome-level gene order conservation was detected. PMID:15514041

  15. Association between invasive ovarian cancer susceptibility and 11 best candidate SNPs from breast cancer genome-wide association study

    DEFF Research Database (Denmark)

    Song, Honglin; Ramus, Susan J; Kjaer, Susanne Krüger;

    2009-01-01

    Because both ovarian and breast cancer are hormone-related and are known to have some predisposition genes in common, we evaluated 11 of the most significant hits (six with confirmed associations with breast cancer) from the breast cancer genome-wide association study for association with invasive.......01-1.13, P-trend = 0.02 for all types of ovarian cancer and OR 1.14 95% CI 1.07-1.22, P-trend = 0.00017 for serous ovarian cancer]. In conclusion, we found that rs4954956 was associated with increased ovarian cancer risk, particularly for serous ovarian cancer. However, none of the six confirmed breast...... ovarian cancer. Eleven SNPs were initially genotyped in 2927 invasive ovarian cancer cases and 4143 controls from six ovarian cancer case-control studies. Genotype frequencies in cases and controls were compared using a likelihood ratio test in a logistic regression model stratified by study. Initially...

  16. Analysis of artificially degraded DNA using STRs and SNPs--results of a collaborative European (EDNAP) exercise

    DEFF Research Database (Denmark)

    Dixon, L A; Dobbins, A E; Pulker, H K;

    2005-01-01

    nucleotide polymorphisms (SNPs). There is general agreement by the European DNA Profiling Group (EDNAP) and the European Network of Forensic Science Institutes (ENFSI) that the reason to implement new markers is to increase the chance of amplifying highly degraded DNA rather than to increase the...... Institute of Standards and Technology (NIST) and a set of degraded DNA stains (blood and saliva). Laboratories tested all three multiplex kits, along with their own existing DNA profiling technique, on the same sets of degraded samples. Results were collated and analysed and, in general, mini-STR systems......Recently, there has been much debate about what kinds of genetic markers should be implemented as new core loci that constitute national DNA databases. The choices lie between conventional STRs, ranging in size from 100 to 450 bp; mini-STRs, with amplicon sizes less than 200 bp; and single...

  17. Typing of 48 autosomal SNPs and amelogenin with GenPlex SNP genotyping system in forensic genetics

    DEFF Research Database (Denmark)

    Tomas Mas, Carmen; Stangegaard, Michael; Børsting, Claus;

    2008-01-01

    GenPlex (Applied Biosystems) is a new SNP genotyping system based on an initial PCR amplification followed by an oligo ligation assay (OLA). The OLA consists of the hybridization of allele and locus specific oligonucleotides (ASOs and LSOs) to PCR products and posterior ligation of ASOs and LSOs....... The ligation products are immobilized to microtitre plates and reporter oligonucleotides (ZipChute probes) are hybridized to the ligation products. ZipChute probes are subsequently eluted and detected using capillary electrophoresis. Applied Biosystems developed the GenPlex SNP genotyping system with...... amelogenin and 48 of the 52 SNPs used in the 52 SNP-plex assay developed by the SNPforID consortium. The system requires equipment that is usually found in forensic genetic laboratories. The use of a robot for performance of the pipetting steps is highly recommendable. A total of 286 individuals from Denmark...

  18. The multiethnic ancestry of Bolivians as revealed by the analysis of Y-chromosome markers.

    Science.gov (United States)

    Cárdenas, Jorge Mario; Heinz, Tanja; Pardo-Seco, Jacobo; Álvarez-Iglesias, Vanesa; Taboada-Echalar, Patricia; Sánchez-Diz, Paula; Carracedo, Ángel; Salas, Antonio

    2015-01-01

    We have analyzed the specific male genetic component of 226 Bolivians recruited in five different regions ("departments"), La Paz, Cochabamba, Pando, Beni, and Santa Cruz. To evaluate the effect of geography on the distribution of genetic variability, the samples were also grouped into three main eco-geographical regions, namely, Andean, Sub-Andean, and Llanos. All the individuals were genotyped for 17 Y-STR and 32 Y-SNP markers. The average Y-chromosome Native American component in Bolivians is 28%, and it is mainly represented by haplogroup Q1a3a, while the average Y-chromosome European ancestry is 65%, and it is mainly represented by haplogroup R1b1-P25. The data indicate that there exists significant population sub-division in the country in terms of continental ancestry. Thus, the partition of ancestries in Llanos, Sub-Andean, and Andean regions is as follows (respectively): (i) Native American ancestry: 47%, 7%, and 19%, (ii) European ancestry: 46%, 86%, and 75%, and (iii) African ancestry: 7%, 7%, and 6%. The population sub-structure in the country is also well mirrored when inferred from an AMOVA analysis, indicating that among-population variance in the country reaches 9.74-11.15%. This suggests the convenience of using regional datasets for forensic applications in Bolivia, instead of using a global and single country database. By comparing the Y-chromosome patterns with those previously reported on the same individuals on autosomal SNPs and mitochondrial DNA (mtDNA), it becomes clear that Bolivians show a strong gender-bias. PMID:25450796

  19. The SNPs Analysis of the Exons of Three Genes of MyoD Gene Family in Seven Swine Breeds (Line)

    Institute of Scientific and Technical Information of China (English)

    LI Jing-fen; LIU Di; YU Hao

    2005-01-01

    The study objects includes seven swine breeds: Minzhu, Sanjiangbaizhu, Yorkshire, Landrace, Junmuyihao, Duroc and Double muscle Yorkshire. According to the sequences of MyoG, MyoD and Myf5 of swine in GenBank, seventeen pairs of primers for MyoG, MyoD and Myf5 were designed. PCR-SSCP technology was applied to detect SNPs of the exons of the three genes. The results showed that no polymorphism was in MyoG and MyoD, and some SNPs were in three exons of Myf5. There was one mutant site in the first exon of Myf5 (G → C), three mutant sites in the second exon of Myf5 (C → A, A → G and G → A); in the third exon of Myf5, there was one base A deficiency at 3 387 bp, three bases T deficiency at 3 417 bp, one mutant site at 3 443 bp (T → C).This study obtained a tendency conclusion that gene frequency of allele M of Myf5 on the one hand is positively correlated with lean meat percentage, on the other hand is correlated with the orientation of selective breeding; it also deduced that allele F is possibly correlated with high lean meat percentage. Through statistical analysis, allele A, B, C of Myf5 have no obvious correlation with lean meat percentage of different swine breeds, In addition, the high polymorphism of Myf5 showed that seven swine breeds are rich in genetic variation, and have high selective competency.

  20. SNPs altering ammonium transport activity of human Rhesus factors characterized by a yeast-based functional assay.

    Directory of Open Access Journals (Sweden)

    Aude Deschuyteneer

    Full Text Available Proteins of the conserved Mep-Amt-Rh family, including mammalian Rhesus factors, mediate transmembrane ammonium transport. Ammonium is an important nitrogen source for the biosynthesis of amino acids but is also a metabolic waste product. Its disposal in urine plays a critical role in the regulation of the acid/base homeostasis, especially with an acid diet, a trait of Western countries. Ammonium accumulation above a certain concentration is however pathologic, the cytotoxicity causing fatal cerebral paralysis in acute cases. Alteration in ammonium transport via human Rh proteins could have clinical outcomes. We used a yeast-based expression assay to characterize human Rh variants resulting from non synonymous single nucleotide polymorphisms (nsSNPs with known or unknown clinical phenotypes and assessed their ammonium transport efficiency, protein level, localization and potential trans-dominant impact. The HsRhAG variants (I61R, F65S associated to overhydrated hereditary stomatocytosis (OHSt, a disease affecting erythrocytes, proved affected in intrinsic bidirectional ammonium transport. Moreover, this study reveals that the R202C variant of HsRhCG, the orthologue of mouse MmRhcg required for optimal urinary ammonium excretion and blood pH control, shows an impaired inherent ammonium transport activity. Urinary ammonium excretion was RHcg gene-dose dependent in mouse, highlighting MmRhcg as a limiting factor. HsRhCG(R202C may confer susceptibility to disorders leading to metabolic acidosis for instance. Finally, the analogous R211C mutation in the yeast ScMep2 homologue also impaired intrinsic activity consistent with a conserved functional role of the preserved arginine residue. The yeast expression assay used here constitutes an inexpensive, fast and easy tool to screen nsSNPs reported by high throughput sequencing or individual cases for functional alterations in Rh factors revealing potential causal variants.

  1. Hundreds of SNPs versus dozens of SSRs: which dataset better characterizes natural clonal lineages in a self-fertilizing fish?

    Directory of Open Access Journals (Sweden)

    Felix eMesak

    2014-11-01

    Full Text Available For more than two decades, mitochondrial DNA sequences and simple sequence repeats (SSRs, or microsatellite loci have served as gold standards in population genetics. More recently, next generation sequencing (NGS has enabled researchers to address biological questions that can benefit from hundreds or even thousands of nuclear single-nucleotide polymorphisms (SNPs generated by restriction-site associated DNA sequencing (RAD-seq. Here we compare the performance of SSR and RAD-seq SNP methods to characterize clonal patterns in a self-fertilizing and highly inbred killifish, Kryptolebias marmoratus (mangrove rivulus in Florida. RAD-seq analyses conducted on 18 inbred lineages of mangrove rivulus obtained from western Florida and a distant location in eastern Florida unveiled 481 polymorphic RAD loci of which 129 were homozygous within individuals and 352 loci were heterozygous in at least one individual. An initial UPGMA phenogram was constructed, based on 32 microsatellite loci, and used as a benchmark for comparisons with SNP-based phenograms, using a number of different criteria for SNP selection. A phenogram produced by the homozygous SNPs was in excellent agreement with the one generated from 32 microsatellite loci. However, heterozygous SNP data and RAD loci with more than one polymorphic site contributed more noise than usable signal and were unable to resolve clades consistently. This is likely due to errors in identifying homologous loci in the absence of a reference genome. In summary, although the RAD data were powerful in distinguishing the clonal lineages identified by SSR analyses, they also carried considerable phylogenetic noise. Our results suggest that RAD-seq methods should be used with caution for inferring fine population structure, and that stringent quality controls are necessary to reduce false phylogenetic signals.

  2. Chromosome heteromorphism quantified by high-resolution bivariate flow karyotyping.

    Science.gov (United States)

    Trask, B; van den Engh, G; Mayall, B; Gray, J W

    1989-11-01

    Maternal and paternal homologues of many chromosome types can be differentiated on the basis of their peak position in Hoechst 33258 versus chromomycin A3 bivariate flow karyotypes. We demonstrate here the magnitude of DNA content differences among normal chromosomes of the same type. Significant peak-position differences between homologues were observed for an average of four chromosome types in each of the karyotypes of 98 different individuals. The frequency of individuals with differences in homologue peak positions varied among chromosome types: e.g., chromosome 15, 61%; chromosome 3, 4%. Flow karyotypes of 33 unrelated individuals were compared to determine the range of peak position among normal chromosomes. Chromosomes Y, 21, 22, 15, 16, 13, 14, and 19 were most heteromorphic, and chromosomes 2-8 and X were least heteromorphic. The largest chromosome 21 was 45% larger than the smallest 21 chromosome observed. The base composition of the variable regions differed among chromosome types. DNA contents of chromosome variants determined from flow karyotypes were closely correlated to measurements of DNA content made of gallocyanin chrome alum-stained metaphase chromosomes on slides. Fluorescence in situ hybridization with chromosome-specific repetitive sequences indicated that variability in their copy number is partly responsible for peak-position variability in some chromosomes. Heteromorphic chromosomes are identified for which parental flow karyotype information will be essential if de novo rearrangements resulting in small DNA content changes are to be detected with flow karyotyping. PMID:2479266

  3. Validation of a single nucleotide polymorphism (SNP) typing assay with 49 SNPs for forensic genetic testing in a laboratory accredited according to the ISO 17025 standard

    DEFF Research Database (Denmark)

    Børsting, Claus; Rockenbauer, Eszter; Morling, Niels

    2009-01-01

    A multiplex assay with 49 autosomal single nucleotide polymorphisms (SNPs) developed for human identification was validated for forensic genetic casework and accredited according to the ISO 17025 standard. The multiplex assay was based on the SNPforID 52plex SNP assay [J.J. Sanchez, C. Phillips, C...... amplified in one PCR reaction. The SNPs were analysed by single base extension (SBE) and capillary electrophoresis. Twenty-three of the original SBE primers were altered to improve the overall robustness of the assay and to simplify the analysis of the SBE results. A total of 216 samples from 50 paternity...... cases and 33 twin cases were typed at least twice for the 49 SNPs. All electropherograms were analysed independently by two expert analysts prior to approval. Based on these results, detailed guidelines for analysis of the SBE products were developed. With these guidelines, the peak height ratio of a...

  4. Evaluation of SNPs in miR-196-a2, miR-27a and miR-146a as risk factors of colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Renata Hezova; Rostislav Vyzula,; Ondrej Slaby; Alena Kovarikova; Julie Bienertova-Vasku; Milana Sachlova; Martina Redova; Anna Vasku; Marek Svoboda; Lenka Radova; Igor Kiss,

    2012-01-01

    AIM:To investigate whether selected single nucleotide polymorphisms (SNPs) in miR-196a2,miR-27a and miR146a genes are associated with sporadic colorectal cancer (CRC).METHODS:In order to investigate the effect of these SNPs in CRC,we performed a case-control study of 197 cases of sporadic CRC and 212 cancer-free controls originating from the Central-European Caucasian population using TaqMan Real-Time polymerase chain reaction and allelic discrimination analysis.RESULTS:The genotype and allele frequencies of SNPs were compared between the cases and the controis.None of the performed analysis showed any statistically significant results.CONCLUSION:Our data suggest a lack of association between rs11614913,rs895819 and rs2910164 and colorectal cancer risk in the Central-European Caucasian population,a population with an extremely high incidence of sporadic colorectal cancer.

  5. Adaptation through chromosomal inversions in Anopheles

    Directory of Open Access Journals (Sweden)

    Diego eAyala

    2014-05-01

    Full Text Available Chromosomal inversions have been repeatedly involved in local adaptation in a large number of animals and plants. The ecological and behavioral plasticity of Anopheles species - human malaria vectors - is mirrored by high amounts of polymorphic inversions. The adaptive significance of chromosomal inversions has been consistently attested by strong and significant correlations between their frequencies and a number of phenotypic traits. Here, we provide an extensive literature review of the different adaptive traits associated with chromosomal inversions in the genus Anopheles. Traits having important consequences for the success of present and future vector control measures, such as insecticide resistance and behavioral changes, are discussed.

  6. Chromosomal abnormalities in patients with sperm disorders

    Directory of Open Access Journals (Sweden)

    L. Y. Pylyp

    2013-02-01

    Full Text Available Chromosomal abnormalities are among the most common genetic causes of spermatogenic disruptions. Carriers of chromosomal abnormalities are at increased risk of infertility, miscarriage or birth of a child with unbalanced karyotype due to the production of unbalanced gametes. The natural selection against chromosomally abnormal sperm usually prevents fertilization with sperm barring in cases of serious chromosomal abnormalities. However, assisted reproductive technologies in general and intracytoplasmic sperm injection in particular, enable the transmission of chromosomal abnormalities to the progeny. Therefore, cytogenetic studies are important in patients with male factor infertility before assisted reproduction treatment. The purpose of the current study was to investigate the types and frequencies of chromosomal abnormalities in 724 patients with infertility and to estimate the risk of chromosomal abnormalities detection in subgroups of patients depending on the severity of spermatogenic disruption, aiming at identifying groups of patients in need of cytogenetic studies. Karyotype analysis was performed in 724 blood samples of men attending infertility clinic. Chromosomal preparation was performed by standard techniques. At least 20 GTG-banded metaphase plates with the resolution from 450 to 750 bands per haploid set were analysed in each case. When chromosomal mosaicism was suspected, this number was increased to 50. Abnormal karyotypes were observed in 48 (6.6% patients, including 67% of autosomal abnormalities and 33% of gonosomal abnormalities. Autosomal abnormalities were represented by structural rearrangements. Reciprocal translocations were the most common type of structural chromosomal abnormalities in the studied group, detected with the frequency of 2.6% (n = 19, followed by Robertsonian translocation, observed with the frequency of 1.2% (n = 9. The frequency of inversions was 0.6% (n = 4. Gonosomal abnormalities included 14 cases

  7. Human Pigmentation, Cutaneous Vitamin D Synthesis and Evolution: Variants of Genes (SNPs) Involved in Skin Pigmentation Are Associated with 25(OH)D Serum Concentration.

    Science.gov (United States)

    Rossberg, Willi; Saternus, Roman; Wagenpfeil, Stefan; Kleber, Marcus; März, Winfried; Reichrath, Sandra; Vogt, Thomas; Reichrath, Jörg

    2016-03-01

    Vitamin D deficiency is common and associated with higher risk for and unfavourable outcome of many diseases. Limited data exist on genetic determinants of serum 25(OH)D concentration. In a cohort of the LURIC study (n=2974, median 25(OH)D concentration 15.5 ng/ml), we tested the hypothesis that variants (SNPs, n=244) of several genes (n=15) involved in different aspects of skin pigmentation, including melanosomal biogenesis (ATP7A, DTNBP1, BLOC1S5, PLDN, PMEL), melanosomal transport within melanocytes (RAB27A, MYO5A, MLPH); or various melanocyte signaling pathways (MC1R, MITF, PAX3, SOX10, DKK1, RACK1, CNR1) are predictive of serum 25(OH)D levels. Eleven SNPs located in 6 genes were associated (p<0.05) with low or high serum 25(OH)D levels, 3 out of these 11 SNPs reached the aimed significance level after correction for multiple comparisons (FDR). In the linear regression model adjusted for sex, body mass index (BMI), year of birth and month of blood sample rs7565264 (MLPH), rs10932949 (PAX3), and rs9328451 (BLOC1S5) showed a significant association with 25(OH)D. The combined impact on variation of 25(OH)D serum levels (coefficient of determination (R(2))) for the 11 SNPs was 1.6% and for the 3 SNPs after FDR 0.3%. In Cox Regression we identified rs2292881 (MLPH) as having a significant association (advantage) with overall survival. Kaplan-Meier analysis did not show any significant impact of individual SNPs on overall survival. In conclusion, these results shed new light on the role of sunlight, skin pigmentation and vitamin D for human evolution. PMID:26977047

  8. Identification and analysis of genome-wide SNPs provide insight into signatures of selection and domestication in channel catfish (Ictalurus punctatus.

    Directory of Open Access Journals (Sweden)

    Luyang Sun

    Full Text Available Domestication and selection for important performance traits can impact the genome, which is most often reflected by reduced heterozygosity in and surrounding genes related to traits affected by selection. In this study, analysis of the genomic impact caused by domestication and artificial selection was conducted by investigating the signatures of selection using single nucleotide polymorphisms (SNPs in channel catfish (Ictalurus punctatus. A total of 8.4 million candidate SNPs were identified by using next generation sequencing. On average, the channel catfish genome harbors one SNP per 116 bp. Approximately 6.6 million, 5.3 million, 4.9 million, 7.1 million and 6.7 million SNPs were detected in the Marion, Thompson, USDA103, Hatchery strain, and wild population, respectively. The allele frequencies of 407,861 SNPs differed significantly between the domestic and wild populations. With these SNPs, 23 genomic regions with putative selective sweeps were identified that included 11 genes. Although the function for the majority of the genes remain unknown in catfish, several genes with known function related to aquaculture performance traits were included in the regions with selective sweeps. These included hypoxia-inducible factor 1β. HIFιβ.. and the transporter gene ATP-binding cassette sub-family B member 5 (ABCB5. HIF1β. is important for response to hypoxia and tolerance to low oxygen levels is a critical aquaculture trait. The large numbers of SNPs identified from this study are valuable for the development of high-density SNP arrays for genetic and genomic studies of performance traits in catfish.

  9. Association analysis of IL10, TNF-α and IL23R-IL12RB2 SNPs with Behçet's disease risk in Western Algeria

    Directory of Open Access Journals (Sweden)

    Ouahiba eKhaib Dit Naib

    2013-10-01

    Full Text Available Objective: We have conducted the first study of the association of interleukin (IL-10, tumor necrosis factor alpha (TNF-α and IL23R-IL12RB2 regionSNPswith Behçet's disease (BD in Western Algeria. Methods: A total of 51 BD patients and 96 unrelated controls from West region of Algeria were genotyped by direct sequencing for 11 SNPs including 2 SNPsfrom the IL10 promoter [c.-819T>C (rs1800871, c.-592A>C (rs1800872], 6 SNPs from the TNF-α promoter [c.-1211T>C (rs1799964, c.-1043C>A (rs1800630, c.-1037C>T (rs1799724, c.-556G>A (rs1800750, c.-488G>A (rs1800629 and c.-418G>A (rs361525], and 3 SNPs from the IL23R-IL12RB2 region [g.67747415A>C (rs12119179, g.67740092G>A (rs11209032 and g.67760140T>C (rs924080]. Results: The minor alleles c.-819T and c.-592A were significantly associated with BD (OR= 2.18; 95% CI 1.28-3.73, p = 0.003; whereas, there was weaker association between TNF-αpromoter SNPs or IL23R-IL12RB2 region and disease risk.Conclusion: Unlike the TNF-αand the IL23R-IL12RB2 region SNPs, the two IL10 SNPs were strongly associated with BD. The -819T, and -592A alleles and the -819TT, -819CT, and -592AA and -592CA genotypes seem to be highly involved in the risk of developing of BD in the population of Western Algeria.

  10. Chromosome landmarks and autosome-sex chromosome translocations in Rumex hastatulus, a plant with XX/XY1Y2 sex chromosome system.

    Science.gov (United States)

    Grabowska-Joachimiak, Aleksandra; Kula, Adam; Książczyk, Tomasz; Chojnicka, Joanna; Sliwinska, Elwira; Joachimiak, Andrzej J

    2015-06-01

    Rumex hastatulus is the North American endemic dioecious plant with heteromorphic sex chromosomes. It is differentiated into two chromosomal races: Texas (T) race characterised by a simple XX/XY sex chromosome system and North Carolina (NC) race with a polymorphic XX/XY1Y2 sex chromosome system. The gross karyotype morphology in NC race resembles the derived type, but chromosomal changes that occurred during its evolution are poorly understood. Our C-banding/DAPI and fluorescence in situ hybridization (FISH) experiments demonstrated that Y chromosomes of both races are enriched in DAPI-positive sequences and that the emergence of polymorphic sex chromosome system was accompanied by the break of ancestral Y chromosome and switch in the localization of 5S rDNA, from autosomes to sex chromosomes (X and Y2). Two contrasting domains were detected within North Carolina Y chromosomes: the older, highly heterochromatinised, inherited from the original Y chromosome and the younger, euchromatic, representing translocated autosomal material. The flow-cytometric DNA estimation showed ∼3.5 % genome downsizing in the North Carolina race. Our results are in contradiction to earlier reports on the lack of heterochromatin within Y chromosomes of this species and enable unambiguous identification of autosomes involved in the autosome-heterosome translocation, providing useful chromosome landmarks for further studies on the karyotype and sex chromosome differentiation in this species. PMID:25394583

  11. Visualization of yeast chromosomal DNA

    Science.gov (United States)

    Lubega, Seth

    1990-01-01

    The DNA molecule is the most significant life molecule since it codes the blue print for other structural and functional molecules of all living organisms. Agarose gel electrophoresis is now being widely used to separate DNA of virus, bacteria, and lower eukaryotes. The task was undertaken of reviewing the existing methods of DNA fractionation and microscopic visualization of individual chromosonal DNA molecules by gel electrophoresis as a basis for a proposed study to investigate the feasibility of separating DNA molecules in free fluids as an alternative to gel electrophoresis. Various techniques were studied. On the molecular level, agarose gel electrophoresis is being widely used to separate chromosomal DNA according to molecular weight. Carl and Olson separate and characterized the entire karyotype of a lab strain of Saccharomyces cerevisiae. Smith et al. and Schwartz and Koval independently reported the visualization of individual DNA molecules migrating through agarose gel matrix during electrophoresis. The techniques used by these researchers are being reviewed in the lab as a basis for the proposed studies.

  12. Dynamic changes in paternal X-chromosome activity during imprinted X-chromosome inactivation in mice

    OpenAIRE

    Patrat, Catherine; Okamoto, Ikuhiro; Diabangouaya, Patricia; Vialon, Vivian; Le Baccon, Patricia; Chow, Jennifer; Heard, Edith

    2009-01-01

    In mammals, X-chromosome dosage compensation is achieved by inactivating one of the two X chromosomes in females. In mice, X inactivation is initially imprinted, with inactivation of the paternal X (Xp) chromosome occurring during preimplantation development. One theory is that the Xp is preinactivated in female embryos, because of its previous silence during meiosis in the male germ line. The extent to which the Xp is active after fertilization and the exact time of onset of X-linked gene si...

  13. Tracking Chromosome Evolution in Southern African Gerbils Using Flow-Sorted Chromosome Paints

    OpenAIRE

    Knight, L.I.; Ng, B. L.; Cheng, W; Fu, B.; Yang, F.; Rambau, R V

    2013-01-01

    Desmodillus and Gerbilliscus (formerly Tatera) comprise a monophyletic group of gerbils (subfamily Gerbillinae) which last shared an ancestor approximately 8 million years ago; diploid chromosome number variation among the species ranges from 2n = 36 to 2n = 50. In an attempt to shed more light on chromosome evolution and speciation in these rodents, we compared the karyotypes of 7 species, representing 3 genera, based on homology data revealed by chromosome painting with probes derived from ...

  14. Sex Chromosome Evolution in Amniotes: Applications for Bacterial Artificial Chromosome Libraries

    OpenAIRE

    Janes, Daniel E.; Nicole Valenzuela; Tariq Ezaz; Chris Amemiya; Edwards, Scott V.

    2011-01-01

    Variability among sex chromosome pairs in amniotes denotes a dynamic history. Since amniotes diverged from a common ancestor, their sex chromosome pairs and, more broadly, sex-determining mechanisms have changed reversibly and frequently. These changes have been studied and characterized through the use of many tools and experimental approaches but perhaps most effectively through applications for bacterial artificial chromosome (BAC) libraries. Individual BAC clones carry 100–200 kb of seque...

  15. Haploidization via Chromosome Elimination: Means and Mechanisms.

    Science.gov (United States)

    Ishii, Takayoshi; Karimi-Ashtiyani, Raheleh; Houben, Andreas

    2016-04-29

    The ability to generate haploids and subsequently induce chromosome doubling significantly accelerates the crop breeding process. Haploids have been induced through the generation of plants from haploid tissues (in situ gynogenesis and androgenesis) and through the selective loss of a parental chromosome set via inter- or intraspecific hybridization. Here, we focus on the mechanisms responsible for this selective chromosome elimination. CENH3, a variant of the centromere-specific histone H3, has been exploited to create an efficient method of haploid induction, and we discuss this approach in some detail. Parallels have been drawn with chromosome-specific elimination, which occurs as a normal part of differentiation and sex determination in many plant and animal systems. PMID:26772657

  16. Cancer chromosomal instability: therapeutic and diagnostic challenges

    OpenAIRE

    McGranahan, Nicholas; Burrell, Rebecca A.; Endesfelder, David; Novelli, Marco R; Swanton, Charles

    2012-01-01

    This review provides a much-needed translational perspective into the issue of aneuploidy and chromosomal instability, discussing the prognostic value of CIN assessment in human tumours, methods to analyze it and how it could be therapeutically targeted.

  17. Lattice animal model of chromosome organization

    Science.gov (United States)

    Iyer, Balaji V. S.; Arya, Gaurav

    2012-07-01

    Polymer models tied together by constraints of looping and confinement have been used to explain many of the observed organizational characteristics of interphase chromosomes. Here we introduce a simple lattice animal representation of interphase chromosomes that combines the features of looping and confinement constraints into a single framework. We show through Monte Carlo simulations that this model qualitatively captures both the leveling off in the spatial distance between genomic markers observed in fluorescent in situ hybridization experiments and the inverse decay in the looping probability as a function of genomic separation observed in chromosome conformation capture experiments. The model also suggests that the collapsed state of chromosomes and their segregation into territories with distinct looping activities might be a natural consequence of confinement.

  18. Chromosome studies in the genus Jatropha L.

    Directory of Open Access Journals (Sweden)

    R.Sasikala and M.Paramathma

    2010-07-01

    Full Text Available The inflorescences of ten species of the genus Jatropha were fixed in Cornoy’s fluid (6:3:1. Acetocarmine stain (2% wasused for staining the pollen mother cells. Seven species exhibited 11 bivalents and 2n =22 and x=11. But the two otherspecies, J.villosa var. villosa and J.villosa var. ramnadensis showed only 10 bivalents and 2n number of 20 chromosomesand x=10. The study concluded the occurrence of two kinds of haploid chromosome numbers of n =10 and n =11. ExceptJatropha tanjorensis, cytological investigation in all species exhibited normal and complete pairing and bivalent formationin metaphase I and equal separation of chromosome in anaphase and indicated that the course of meiosis was normal.Jatropha tanjorensis did not exhibit normal course of meiosis and no proper count of chromosomes could be made. Presentchromosomal studies in Jatropha revealed the existence of two basic chromosomes numbers x = 5 and x = 6.

  19. System for the analysis of plant chromosomes

    International Nuclear Information System (INIS)

    The paper describes a computer system for the automation workers of recognition analysis and interpretation of plant chromosomes. This system permit to carry out the analysis in a more comfortable and faster way, using the image processing techniques

  20. Label Free Chromosome Translocation Detection with Silicon nanowires

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Andersen, Karsten Brandt; Frøhling, Kasper Bayer;

    HROMOSOME translocation, which is a rearrangement of arms between two chromosomes, is a major group of chromosome abnormalities leading to cancer. As a result, two derivative chromosomes with sequences coming from both chromosomes are formed. The current translocation detection method is a Fluore...