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Sample records for polymorphism based snp

  1. Developments of geriatric autopsy database and Internet-based database of Japanese single nucleotide polymorphisms for geriatric research (JG-SNP).

    PubMed

    Sawabe, Motoji; Arai, Tomio; Kasahara, Ichiro; Esaki, Yukiyoshi; Nakahara, Ken-ichi; Hosoi, Takayuki; Orimo, Hajime; Takubo, Kaiyo; Murayama, Shigeo; Tanaka, Noriko

    2004-08-01

    To facilitate geriatric research on the roles of genetic polymorphisms of candidate genes, two databases were developed based on data obtained from autopsy examinations of elderly subjects: the geriatric autopsy database (GEAD) and the Japanese single nucleotide polymorphisms (SNP) database for geriatric research (JG-SNP) which is accessible on the Internet (http://www.tmgh.metro.tokyo.jp/jg-snp/english/E_top.html). The data for the GEAD were derived from 1074 consecutive autopsy cases (565 male and 509 female cases) with an average age of 80 years. The GEAD was installed on a stand-alone Windows 2000 server using Oracle 8i as the database application. The GEAD contains clinical diagnoses of 26 geriatric diseases, histories of smoking and alcohol consumption, pathological findings (720 items), severity of atherosclerosis, genetic polymorphism data, etc. On the JG-SNP website, case distribution corresponding to a specified SNP or disease can be searched or downloaded. Although there are several Internet-based SNP databases such as dbSNP, no databases are available at present on the web that contain both SNP data and phenotypic data. As autopsy studies can provide large amounts of accurate medical information, including the presence of undiagnosed diseases such as latent cancers, the GEAD is a unique and excellent database for research on genetic polymorphisms. PMID:15336912

  2. Investigating single nucleotide polymorphism (SNP) density in the human genome and its implications for molecular evolution.

    PubMed

    Zhao, Zhongming; Fu, Yun-Xin; Hewett-Emmett, David; Boerwinkle, Eric

    2003-07-17

    We investigated the single nucleotide polymorphism (SNP) density across the human genome and in different genic categories using two SNP databases: Celera's CgsSNP, which includes SNPs identified by comparing genomic sequences, and Celera's RefSNP, which includes SNPs from a variety of sources and is biased toward disease-associated genes. Based on CgsSNP, the average numbers of SNPs per 10 kb was 8.33, 8.44, and 8.09 in the human genome, in intergenic regions, and in genic regions, respectively. In genic regions, the SNP density in intronic, exonic and adjoining untranslated regions was 8.21, 5.28, and 7.51 SNPs per 10 kb, respectively. The pattern of SNP density based on RefSNP was different from that based on CgsSNP, emphasizing its utility for genotype-phenotype association studies but not for most population genetic studies. The number of SNPs per chromosome was correlated with chromosome length, but the density of SNPs estimated by CgsSNP was not significantly correlated with the GC content of the chromosome. Based on CgsSNP, the ratio of nonsense to missense mutations (0.027), the ratio of missense to silent mutations (1.15), and the ratio of non-synonymous to synonymous mutations (1.18) was less than half of that expected in a human protein coding sequence under the neutral mutation theory, reflecting a role for natural selection, especially purifying selection. PMID:12909357

  3. Analysis of DNA polymorphisms in sugar beet (Beta vulgaris L.) and development of an SNP-based map of expressed genes.

    PubMed

    Schneider, Katharina; Kulosa, Dagmar; Soerensen, Thomas Rosleff; Möhring, Silke; Heine, Martin; Durstewitz, Gregor; Polley, Andreas; Weber, Eberhard; Jamsari; Lein, Jens; Hohmann, Uwe; Tahiro, Emma; Weisshaar, Bernd; Schulz, Britta; Koch, Georg; Jung, Christian; Ganal, Martin

    2007-09-01

    A panel of 13 sugar beet lines and one genotype each of the Beta vulgaris cultivars red beet and Swiss chard, and B. vulgaris ssp. maritima were used to identify polymorphisms in alignments of genomic DNA sequences derived from 315 EST- and 43 non-coding RFLP-derived loci. In sugar beet lines, loci of expressed genes showed an average SNP frequency of 1/72 bp, 1 in 58 bp in non-coding sequences, increasing to 1/47 bp upon the addition of the remaining genotypes. Within analysed DNA fragments, alleles at different SNP positions displayed linkage disequilibrium indicative of haplotype structures. On average 2.7 haplotypes were found in sugar beet lines, and haplotype conservation in expressed genes appeared to exceed 500 bp in length. Seven different genotyping techniques including SNP detection by MALDI-TOF mass spectrometry, pyrosequencing and fluorescence scanning of labelled nucleotides were employed to perform 712 segregation analyses for 538 markers in three F(2) populations. Functions were predicted for 492 mapped sequences. Genetic maps comprised 305 loci covering 599.8 cM in population K1, 241 loci distributed over 636.6 cM in population D2, and 166 loci over 507.1 cM in population K2, respectively. Based on 156 markers common to more than one population an integrated map was constructed with 524 loci covering 664.3 cM. For 377 loci the genome positions of the most similar sequences from A. thaliana were identified, but little evidence for previously presented ancestral genome structures was found. PMID:17622508

  4. Rapid identification of Brucella isolates to the species level by real time PCR based single nucleotide polymorphism (SNP) analysis

    PubMed Central

    Gopaul, Krishna K; Koylass, Mark S; Smith, Catherine J; Whatmore, Adrian M

    2008-01-01

    Background Brucellosis, caused by members of the genus Brucella, remains one of the world's major zoonotic diseases. Six species have classically been recognised within the family Brucella largely based on a combination of classical microbiology and host specificity, although more recently additional isolations of novel Brucella have been reported from various marine mammals and voles. Classical identification to species level is based on a biotyping approach that is lengthy, requires extensive and hazardous culturing and can be difficult to interpret. Here we describe a simple and rapid approach to identification of Brucella isolates to the species level based on real-time PCR analysis of species-specific single nucleotide polymorphisms (SNPs) that were identified following a robust and extensive phylogenetic analysis of the genus. Results Seven pairs of short sequence Minor Groove Binding (MGB) probes were designed corresponding to SNPs shown to possess an allele specific for each of the six classical Brucella spp and the marine mammal Brucella. Assays were optimised to identical reaction parameters in order to give a multiple outcome assay that can differentiate all the classical species and Brucella isolated from marine mammals. The scope of the assay was confirmed by testing of over 300 isolates of Brucella, all of which typed as predicted when compared to other phenotypic and genotypic approaches. The assay is sensitive being capable of detecting and differentiating down to 15 genome equivalents. We further describe the design and testing of assays based on three additional SNPs located within the 16S rRNA gene that ensure positive discrimination of Brucella from close phylogenetic relatives on the same platform. Conclusion The multiple-outcome assay described represents a new tool for the rapid, simple and unambiguous characterisation of Brucella to the species level. Furthermore, being based on a robust phylogenetic framework, the assay provides a platform

  5. Single Nucleotide Polymorphism (SNP)-Based Loss of Heterozygosity (LOH) Testing by Real Time PCR in Patients Suspect of Myeloproliferative Disease

    PubMed Central

    Huijsmans, Cornelis J. J.; Poodt, Jeroen; Damen, Jan; van der Linden, Johannes C.; Savelkoul, Paul H. M.; Pruijt, Johannes F. M.; Hilbink, Mirrian; Hermans, Mirjam H. A.

    2012-01-01

    During tumor development, loss of heterozygosity (LOH) often occurs. When LOH is preceded by an oncogene activating mutation, the mutant allele may be further potentiated if the wild-type allele is lost or inactivated. In myeloproliferative neoplasms (MPN) somatic acquisition of JAK2V617F may be followed by LOH resulting in loss of the wild type allele. The occurrence of LOH in MPN and other proliferative diseases may lead to a further potentiating the mutant allele and thereby increasing morbidity. A real time PCR based SNP profiling assay was developed and validated for LOH detection of the JAK2 region (JAK2LOH). Blood of a cohort of 12 JAK2V617F-positive patients (n = 6 25–50% and n = 6>50% JAK2V617F) and a cohort of 81 patients suspected of MPN was stored with EDTA and subsequently used for validation. To generate germ-line profiles, non-neoplastic formalin-fixed paraffin-embedded tissue from each patient was analyzed. Results of the SNP assay were compared to those of an established Short Tandem Repeat (STR) assay. Both assays revealed JAK2LOH in 1/6 patients with 25–50% JAK2V617F. In patients with >50% JAK2V617F, JAK2LOH was detected in 6/6 by the SNP assay and 5/6 patients by the STR assay. Of the 81 patients suspected of MPN, 18 patients carried JAK2V617F. Both the SNP and STR assay demonstrated the occurrence of JAK2LOH in 5 of them. In the 63 JAK2V617F-negative patients, no JAK2LOH was observed by SNP and STR analyses. The presented SNP assay reliably detects JAK2LOH and is a fast and easy to perform alternative for STR analyses. We therefore anticipate the SNP approach as a proof of principle for the development of LOH SNP-assays for other clinically relevant LOH loci. PMID:22768290

  6. Quantify single nucleotide polymorphism (SNP) ratio in pooled DNA based on normalized fluorescence real-time PCR

    PubMed Central

    Yu, Airong; Geng, Haifeng; Zhou, Xuerui

    2006-01-01

    Background Conventional real-time PCR to quantify the allele ratio in pooled DNA mainly depends on PCR amplification efficiency determination and Ct value, which is defined as the PCR cycle number at which the fluorescence emission exceeds the fixed threshold. Because of the nature of exponential calculation, slight errors are multiplied and the variations of the results seem too large. We have developed a new PCR data point analysis strategy for allele ratio quantification based on normalized fluorescence ratio. Results In our method, initial reaction background fluorescence was determined based upon fitting of raw fluorescence data to four-parametric sigmoid function. After that, each fluorescence data point was first subtracted by respective background fluorescence and then each subtracted fluorescence data point was divided by the specific background fluorescence to get normalized fluorescence. By relating the normalized fluorescence ratio to the premixed known allele ratio of two alleles in standard samples, standard linear regression equation was generated, from which unknown specimens allele ratios were extrapolated using the measured normalized fluorescence ratio. In this article, we have compared the results of the proposed method with those of baseline subtracted fluorescence ratio method and conventional Ct method. Conclusion Results demonstrated that the proposed method could improve the reliability, precision, and repeatability for quantifying allele ratios. At the same time, it has the potential of fully automatic allelic ratio quantification. PMID:16764712

  7. Development of Single Nucleotide Polymorphism (SNP) Markers for Use in Commercial Maize (Zea Mays L.) Germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of single nucleotide polymorphism (SNP) markers in maize offer the opportunity to utilize DNA markers in many new areas of population genetics, gene discovery, plant breeding, and germplasm identification. However, the steps from sequencing and SNP discovery to SNP marker design and ...

  8. Linkage mapping bovine EST-based SNP

    PubMed Central

    Snelling, Warren M; Casas, Eduardo; Stone, Roger T; Keele, John W; Harhay, Gregory P; Bennett, Gary L; Smith, Timothy PL

    2005-01-01

    Background Existing linkage maps of the bovine genome primarily contain anonymous microsatellite markers. These maps have proved valuable for mapping quantitative trait loci (QTL) to broad regions of the genome, but more closely spaced markers are needed to fine-map QTL, and markers associated with genes and annotated sequence are needed to identify genes and sequence variation that may explain QTL. Results Bovine expressed sequence tag (EST) and bacterial artificial chromosome (BAC)sequence data were used to develop 918 single nucleotide polymorphism (SNP) markers to map genes on the bovine linkage map. DNA of sires from the MARC reference population was used to detect SNPs, and progeny and mates of heterozygous sires were genotyped. Chromosome assignments for 861 SNPs were determined by twopoint analysis, and positions for 735 SNPs were established by multipoint analyses. Linkage maps of bovine autosomes with these SNPs represent 4585 markers in 2475 positions spanning 3058 cM . Markers include 3612 microsatellites, 913 SNPs and 60 other markers. Mean separation between marker positions is 1.2 cM. New SNP markers appear in 511 positions, with mean separation of 4.7 cM. Multi-allelic markers, mostly microsatellites, had a mean (maximum) of 216 (366) informative meioses, and a mean 3-lod confidence interval of 3.6 cM Bi-allelic markers, including SNP and other marker types, had a mean (maximum) of 55 (191) informative meioses, and were placed within a mean 8.5 cM 3-lod confidence interval. Homologous human sequences were identified for 1159 markers, including 582 newly developed and mapped SNP. Conclusion Addition of these EST- and BAC-based SNPs to the bovine linkage map not only increases marker density, but provides connections to gene-rich physical maps, including annotated human sequence. The map provides a resource for fine-mapping quantitative trait loci and identification of positional candidate genes, and can be integrated with other data to guide and

  9. Substantial SNP-based heritability estimates for working memory performance

    PubMed Central

    Vogler, C; Gschwind, L; Coynel, D; Freytag, V; Milnik, A; Egli, T; Heck, A; de Quervain, D J-F; Papassotiropoulos, A

    2014-01-01

    Working memory (WM) is an important endophenotype in neuropsychiatric research and its use in genetic association studies is thought to be a promising approach to increase our understanding of psychiatric disease. As for any genetically complex trait, demonstration of sufficient heritability within the specific study context is a prerequisite for conducting genetic studies of that trait. Recently developed methods allow estimating trait heritability using sets of common genetic markers from genome-wide association study (GWAS) data in samples of unrelated individuals. Here we present single-nucleotide polymorphism (SNP)-based heritability estimates (h2SNP) for a WM phenotype. A Caucasian sample comprising a total of N=2298 healthy and young individuals was subjected to an N-back WM task. We calculated the genetic relationship between all individuals on the basis of genome-wide SNP data and performed restricted maximum likelihood analyses for variance component estimation to derive the h2SNP estimates. Heritability estimates for three 2-back derived WM performance measures based on all autosomal chromosomes ranged between 31 and 41%, indicating a substantial SNP-based heritability for WM traits. These results indicate that common genetic factors account for a prominent part of the phenotypic variation in WM performance. Hence, the application of GWAS on WM phenotypes is a valid method to identify the molecular underpinnings of WM. PMID:25203169

  10. Differentiation of drug and non-drug Cannabis using a single nucleotide polymorphism (SNP) assay.

    PubMed

    Rotherham, D; Harbison, S A

    2011-04-15

    Cannabis sativa is both an illegal drug and a legitimate crop. The differentiation of illegal drug Cannabis from non-drug forms of Cannabis is relevant in the context of the growth of fibre and seed oil varieties of Cannabis for commercial purposes. This differentiation is currently determined based on the levels of tetrahydrocannabinol (THC) in adult plants. DNA based methods have the potential to assay Cannabis material unsuitable for analysis using conventional means including seeds, pollen and severely degraded material. The purpose of this research was to develop a single nucleotide polymorphism (SNP) assay for the differentiation of "drug" and "non-drug"Cannabis plants. An assay was developed based on four polymorphisms within a 399 bp fragment of the tetrahydrocannabinolic acid (THCA) synthase gene, utilising the snapshot multiplex kit. This SNP assay was tested on 94 Cannabis plants, which included 10 blind samples, and was able to differentiate between "drug" and "non-drug"Cannabis in all cases, while also differentiating between Cannabis and other species. Non-drug plants were found to be homozygous at the four sites assayed while drug Cannabis plants were either homozygous or heterozygous. PMID:21036496

  11. Identification, validation and survey of a single nucleotide polymorphism (SNP) associated with pungency in Capsicum spp.

    PubMed

    Garcés-Claver, Ana; Fellman, Shanna Moore; Gil-Ortega, Ramiro; Jahn, Molly; Arnedo-Andrés, María S

    2007-11-01

    A single nucleotide polymorphism (SNP) associated with pungency was detected within an expressed sequence tag (EST) of 307 bp. This fragment was identified after expression analysis of the EST clone SB2-66 in placenta tissue of Capsicum fruits. Sequence alignments corresponding to this new fragment allowed us to identify an SNP between pungent and non-pungent accessions. Two methods were chosen for the development of the SNP marker linked to pungency: tetra-primer amplification refractory mutation system-PCR (tetra-primer ARMS-PCR) and cleaved amplified polymorphic sequence. Results showed that both methods were successful in distinguishing genotypes. Nevertheless, tetra-primer ARMS-PCR was chosen for SNP genotyping because it was more rapid, reliable and less cost-effective. The utility of this SNP marker for pungency was demonstrated by the ability to distinguish between 29 pungent and non-pungent cultivars of Capsicum annuum. In addition, the SNP was also associated with phenotypic pungent character in the tested genotypes of C. chinense, C. baccatum, C. frutescens, C. galapagoense, C. eximium, C. tovarii and C. cardenasi. This SNP marker is a faster, cheaper and more reproducible method for identifying pungent peppers than other techniques such as panel tasting, and allows rapid screening of the trait in early growth stages. PMID:17882396

  12. Drug-SNPing: an integrated drug-based, protein interaction-based tagSNP-based pharmacogenomics platform for SNP genotyping.

    PubMed

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

    2013-03-15

    Many drug or single nucleotide polymorphism (SNP)-related resources and tools have been developed, but connecting and integrating them is still a challenge. Here, we describe a user-friendly web-based software package, named Drug-SNPing, which provides a platform for the integration of drug information (DrugBank and PharmGKB), protein-protein interactions (STRING), tagSNP selection (HapMap) and genotyping information (dbSNP, REBASE and SNP500Cancer). DrugBank-based inputs include the following: (i) common name of the drug, (ii) synonym or drug brand name, (iii) gene name (HUGO) and (iv) keywords. PharmGKB-based inputs include the following: (i) gene name (HUGO), (ii) drug name and (iii) disease-related keywords. The output provides drug-related information, metabolizing enzymes and drug targets, as well as protein-protein interaction data. Importantly, tagSNPs of the selected genes are retrieved for genotyping analyses. All drug-based and protein-protein interaction-based SNP genotyping information are provided with PCR-RFLP (PCR-restriction enzyme length polymorphism) and TaqMan probes. Thus, users can enter any drug keywords/brand names to obtain immediate information that is highly relevant to genotyping for pharmacogenomics research. PMID:23418190

  13. Developing single nucleotide polymorphism (SNP) markers from transcriptome sequences for identification of longan (Dimocarpus longan) germplasm

    PubMed Central

    Wang, Boyi; Tan, Hua-Wei; Fang, Wanping; Meinhardt, Lyndel W; Mischke, Sue; Matsumoto, Tracie; Zhang, Dapeng

    2015-01-01

    Longan (Dimocarpus longan Lour.) is an important tropical fruit tree crop. Accurate varietal identification is essential for germplasm management and breeding. Using longan transcriptome sequences from public databases, we developed single nucleotide polymorphism (SNP) markers; validated 60 SNPs in 50 longan germplasm accessions, including cultivated varieties and wild germplasm; and designated 25 SNP markers that unambiguously identified all tested longan varieties with high statistical rigor (P<0.0001). Multiple trees from the same clone were verified and off-type trees were identified. Diversity analysis revealed genetic relationships among analyzed accessions. Cultivated varieties differed significantly from wild populations (Fst=0.300; P<0.001), demonstrating untapped genetic diversity for germplasm conservation and utilization. Within cultivated varieties, apparent differences between varieties from China and those from Thailand and Hawaii indicated geographic patterns of genetic differentiation. These SNP markers provide a powerful tool to manage longan genetic resources and breeding, with accurate and efficient genotype identification. PMID:26504559

  14. Developing Single Nucleotide Polymorphism (SNP) markers from transcriptome sequences for the identification of longan (Dimocarpus longan) germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Longan (Dimocarpus longan Lour.) is an important tropical fruit tree crop. Accurate varietal identification is essential for germplasm management and breeding. Using longan transcriptome sequences from public databases, we developed single nucleotide polymorphism (SNP) markers; validated 60 SNPs in...

  15. Identifying Litchi (Litchi chinensis Sonn.) Cultivars and Their Genetic Relationships Using Single Nucleotide Polymorphism (SNP) Markers

    PubMed Central

    Liu, Wei; Xiao, Zhidan; Bao, Xiuli; Yang, Xiaoyan; Fang, Jing; Xiang, Xu

    2015-01-01

    Litchi is an important fruit tree in tropical and subtropical areas of the world. However, there is widespread confusion regarding litchi cultivar nomenclature and detailed information of genetic relationships among litchi germplasm is unclear. In the present study, the potential of single nucleotide polymorphism (SNP) for the identification of 96 representative litchi accessions and their genetic relationships in China was evaluated using 155 SNPs that were evenly spaced across litchi genome. Ninety SNPs with minor allele frequencies above 0.05 and a good genotyping success rate were used for further analysis. A relatively high level of genetic variation was observed among litchi accessions, as quantified by the expected heterozygosity (He = 0.305). The SNP based multilocus matching identified two synonymous groups, ‘Heiye’ and ‘Wuye’, and ‘Chengtuo’ and ‘Baitangli 1’. A subset of 14 SNPs was sufficient to distinguish all the non-redundant litchi genotypes, and these SNPs were proven to be highly stable by repeated analyses of a selected group of cultivars. Unweighted pair-group method of arithmetic averages (UPGMA) cluster analysis divided the litchi accessions analyzed into four main groups, which corresponded to the traits of extremely early-maturing, early-maturing, middle-maturing, and late-maturing, indicating that the fruit maturation period should be considered as the primary criterion for litchi taxonomy. Two subpopulations were detected among litchi accessions by STRUCTURE analysis, and accessions with extremely early- and late-maturing traits showed membership coefficients above 0.99 for Cluster 1 and Cluster 2, respectively. Accessions with early- and middle-maturing traits were identified as admixture forms with varying levels of membership shared between the two clusters, indicating their hybrid origin during litchi domestication. The results of this study will benefit litchi germplasm conservation programs and facilitate maximum

  16. Development of EST-based SNP and InDel markers and their utilization in tetraploid cotton genetic mapping

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Expressed sequence tags (ESTs) were analyzed in silico in order to identify single nucleotide polymorphisms (SNPs) and insertion-deletion polymorphisms (InDels) in cotton. A total of 1349 EST-based SNP and InDel markers were developed by comparing ESTs between Gossypium hirsutum and G. barbadense, m...

  17. An Improved Opposition-Based Learning Particle Swarm Optimization for the Detection of SNP-SNP Interactions

    PubMed Central

    Shang, Junliang; Sun, Yan; Li, Shengjun; Liu, Jin-Xing; Zheng, Chun-Hou; Zhang, Junying

    2015-01-01

    SNP-SNP interactions have been receiving increasing attention in understanding the mechanism underlying susceptibility to complex diseases. Though many works have been done for the detection of SNP-SNP interactions, the algorithmic development is still ongoing. In this study, an improved opposition-based learning particle swarm optimization (IOBLPSO) is proposed for the detection of SNP-SNP interactions. Highlights of IOBLPSO are the introduction of three strategies, namely, opposition-based learning, dynamic inertia weight, and a postprocedure. Opposition-based learning not only enhances the global explorative ability, but also avoids premature convergence. Dynamic inertia weight allows particles to cover a wider search space when the considered SNP is likely to be a random one and converges on promising regions of the search space while capturing a highly suspected SNP. The postprocedure is used to carry out a deep search in highly suspected SNP sets. Experiments of IOBLPSO are performed on both simulation data sets and a real data set of age-related macular degeneration, results of which demonstrate that IOBLPSO is promising in detecting SNP-SNP interactions. IOBLPSO might be an alternative to existing methods for detecting SNP-SNP interactions. PMID:26236727

  18. Single Nucleotide Polymorphism (SNP) in the Adiponectin Gene and Cardiovascular Disease.

    PubMed

    Chirumbolo, Salvatore

    2016-07-01

    Dear Editor, The recent article by Mohammadzadeh et al.[1] on the latest issue of this Journal showed that the T allele +276G/T SNP of ADIPOQ gene is more associated with the increasing risk of coronary artery disease (CAD) in subjects with type 2 diabetes. Adipocytes were described in myocardial tissue of CAD patients and their role recently discussed[2,3]. Susceptibility to CAD by polymorphism in the Q gene of adiponectin has been reported for 3'-UTR, which harbours some genetic loci associated with metabolic risks and atherosclerosis[4]. Actually, previous studies have shown that the haplotype SNP +276G>T was associated with a decreased risk of CAD, after adjustment for potential confounding factors, therefore some controversial opinion still exists[5]. This evidence should be associated with the role exerted by adipocytes and adiponectin in heart physiology. In particular, in hypertensive disorder complicating pregnancy (HDCP), by investigating the population frequency of alleles, genotypes, and haplotypes of two single nucleotide polymorphisms (SNPs), namely +45T>G (rs2241766) and +276G>T (rs1501299), some authors found that the SNP +276 TT genotype was significantly associated with protection against HDCP, when compared to the pooled G genotypes[6]. Moreover, the same +276G/T SNP haplotype was strongly associated with biliary atresia, an intractable neonatal inflammatory and obliterative cholangiopathy, leading to progressive fibrosis and cirrhosis[7]. CAD is closely related to adiponectin biology. The same isoforms of adiponectin seem to be not associated to CAD severity but to glucose metabolism and its impairment[8]. In the paper by Mohammadzadeh et al.[1], T allele in +276G/T SNP haplotype is highly associated with CAD in subjects with type 2 diabetes, but this linkage should be reappraised if related much more to diabetes rather than CAD. Association of T allele in the indicated SNP with CAD may be an indirect consequence of type 2 diabetes, as reported

  19. eSNPO: An eQTL-based SNP Ontology and SNP functional enrichment analysis platform

    PubMed Central

    Li, Jin; Wang, Limei; Jiang, Tao; Wang, Jizhe; Li, Xue; Liu, Xiaoyan; Wang, Chunyu; Teng, Zhixia; Zhang, Ruijie; Lv, Hongchao; Guo, Maozu

    2016-01-01

    Genome-wide association studies (GWASs) have mined many common genetic variants associated with human complex traits like diseases. After that, the functional annotation and enrichment analysis of significant SNPs are important tasks. Classic methods are always based on physical positions of SNPs and genes. Expression quantitative trait loci (eQTLs) are genomic loci that contribute to variation in gene expression levels and have been proven efficient to connect SNPs and genes. In this work, we integrated the eQTL data and Gene Ontology (GO), constructed associations between SNPs and GO terms, then performed functional enrichment analysis. Finally, we constructed an eQTL-based SNP Ontology and SNP functional enrichment analysis platform. Taking Parkinson Disease (PD) as an example, the proposed platform and method are efficient. We believe eSNPO will be a useful resource for SNP functional annotation and enrichment analysis after we have got significant disease related SNPs. PMID:27470167

  20. eSNPO: An eQTL-based SNP Ontology and SNP functional enrichment analysis platform.

    PubMed

    Li, Jin; Wang, Limei; Jiang, Tao; Wang, Jizhe; Li, Xue; Liu, Xiaoyan; Wang, Chunyu; Teng, Zhixia; Zhang, Ruijie; Lv, Hongchao; Guo, Maozu

    2016-01-01

    Genome-wide association studies (GWASs) have mined many common genetic variants associated with human complex traits like diseases. After that, the functional annotation and enrichment analysis of significant SNPs are important tasks. Classic methods are always based on physical positions of SNPs and genes. Expression quantitative trait loci (eQTLs) are genomic loci that contribute to variation in gene expression levels and have been proven efficient to connect SNPs and genes. In this work, we integrated the eQTL data and Gene Ontology (GO), constructed associations between SNPs and GO terms, then performed functional enrichment analysis. Finally, we constructed an eQTL-based SNP Ontology and SNP functional enrichment analysis platform. Taking Parkinson Disease (PD) as an example, the proposed platform and method are efficient. We believe eSNPO will be a useful resource for SNP functional annotation and enrichment analysis after we have got significant disease related SNPs. PMID:27470167

  1. Citrus (Rutaceae) SNP markers based on Competitive Allele-Specific PCR; transferability across the Aurantioideae subfamily1

    PubMed Central

    Garcia-Lor, Andres; Ancillo, Gema; Navarro, Luis; Ollitrault, Patrick

    2013-01-01

    • Premise of the study: Single nucleotide polymorphism (SNP) markers based on Competitive Allele-Specific PCR (KASPar) were developed from sequences of three Citrus species. Their transferability was tested in 63 Citrus genotypes and 19 relative genera of the subfamily Aurantioideae to estimate the potential of SNP markers, selected from a limited intrageneric discovery panel, for ongoing broader diversity analysis at the intra- and intergeneric levels and systematic germplasm bank characterization. • Methods and Results: Forty-two SNP markers were developed using KASPar technology. Forty-one were successfully genotyped in all of the Citrus germplasm, where intra- and interspecific polymorphisms were observed. The transferability and diversity decreased with increasing taxonomic distance. • Conclusions: SNP markers based on the KASPar method developed from sequence data of a limited intrageneric discovery panel provide a valuable molecular resource for genetic diversity analysis of germplasm within a genus and should be useful for germplasm fingerprinting at a much broader diversity level. PMID:25202535

  2. How valid is single nucleotide polymorphism (SNP) diagnosis for the individual risk assessment of breast cancer?

    PubMed

    Tempfer, Clemens B; Hefler, Lukas A; Schneeberger, Christian; Huber, Johannes C

    2006-03-01

    The number of reports investigating disease susceptibility based on the carriage of low-penetrance, high-frequency single nucleotide polymorphisms (SNPs) has increased in recent years. Evidence is accumulating defining specific individual variations in breast cancer susceptibility. Genetic variations of estradiol and xenobiotics metabolisms as well as genes involved in cell-cycle control have been described as significant contributors to breast cancer susceptibility, with variations depending on ethnic background and co-factors such as smoking and family history of breast cancer. In sum, the highest level of evidence to date linking SNPs and breast cancer comes from nested case-control studies within the prospective Nurses' Health Study. These data establish seven SNPs - hPRB +331G/A, AR CAG repeat, CYP19 (TTTA)10, CYP1A1 MspI, VDR FOK1, XRCC1 Arg194Trp and XRCC2 Arg188His - as small but significant risk factors for spontaneous, non-hereditary breast cancer. In addition, meta-analysis of data in the literature establishes the TGFBR1*6A, HRAS1, GSTP Ile105Val and GSTM1 SNPs as low-penetrance genetic risk factors of sporadic breast cancer. The clinical consequences of such a risk elevation may be detailed instruction of the patient as to general measures of breast cancer prevention such as a low-fat diet, optimization of body mass index, physical exercise, avoidance of alcohol and long-term hormone replacement therapy, and participation in a breast cancer screening program between the ages of 50 and 70 years. Specific surgical or drug interventions such as prophylactic mastectomy and oophorectomy or prophylactic intake of tamoxifen are not indicated based on SNP analysis at this time. PMID:16835078

  3. Use of the Illumina GoldenGate assay for single nucleotide polymorphism (SNP) genotyping in cereal crops.

    PubMed

    Chao, Shiaoman; Lawley, Cindy

    2015-01-01

    Highly parallel genotyping assays, such as the GoldenGate assay developed by Illumina, capable of interrogating up to 3,072 single nucleotide polymorphisms (SNPs) simultaneously, have greatly facilitated genome-wide studies, particularly for crops with large and complex genome structures. In this report, we provide detailed information and guidelines regarding genomic DNA preparation, SNP assay design, SNP assay protocols, and genotype calling using Illumina's GenomeStudio software. PMID:25373766

  4. Quadruplex-single nucleotide polymorphisms (Quad-SNP) influence gene expression difference among individuals

    PubMed Central

    Baral, Aradhita; Kumar, Pankaj; Halder, Rashi; Mani, Prithvi; Yadav, Vinod Kumar; Singh, Ankita; Das, Swapan K.; Chowdhury, Shantanu

    2012-01-01

    Non-canonical guanine quadruplex structures are not only predominant but also conserved among bacterial and mammalian promoters. Moreover recent findings directly implicate quadruplex structures in transcription. These argue for an intrinsic role of the structural motif and thereby posit that single nucleotide polymorphisms (SNP) that compromise the quadruplex architecture could influence function. To test this, we analysed SNPs within quadruplex motifs (Quad-SNP) and gene expression in 270 individuals across four populations (HapMap) representing more than 14 500 genotypes. Findings reveal significant association between quadruplex-SNPs and expression of the corresponding gene in individuals (P < 0.0001). Furthermore, analysis of Quad-SNPs obtained from population-scale sequencing of 1000 human genomes showed relative selection bias against alteration of the structural motif. To directly test the quadruplex-SNP-transcription connection, we constructed a reporter system using the RPS3 promoter—remarkable difference in promoter activity in the ‘quadruplex-destabilized’ versus ‘quadruplex-intact’ promoter was noticed. As a further test, we incorporated a quadruplex motif or its disrupted counterpart within a synthetic promoter reporter construct. The quadruplex motif, and not the disrupted-motif, enhanced transcription in human cell lines of different origin. Together, these findings build direct support for quadruplex-mediated transcription and suggest quadruplex-SNPs may play significant role in mechanistically understanding variations in gene expression among individuals. PMID:22238381

  5. A SNP-Based Molecular Barcode for Characterization of Common Wheat

    PubMed Central

    Gao, LiFeng; Jia, JiZeng; Kong, XiuYing

    2016-01-01

    Wheat is grown as a staple crop worldwide. It is important to develop an effective genotyping tool for this cereal grain both to identify germplasm diversity and to protect the rights of breeders. Single-nucleotide polymorphism (SNP) genotyping provides a means for developing a practical, rapid, inexpensive and high-throughput assay. Here, we investigated SNPs as robust markers of genetic variation for typing wheat cultivars. We identified SNPs from an array of 9000 across a collection of 429 well-known wheat cultivars grown in China, of which 43 SNP markers with high minor allele frequency and variations discriminated the selected wheat varieties and their wild ancestors. This SNP-based barcode will allow for the rapid and precise identification of wheat germplasm resources and newly released varieties and will further assist in the wheat breeding program. PMID:26985664

  6. A SNP-Based Molecular Barcode for Characterization of Common Wheat.

    PubMed

    Gao, LiFeng; Jia, JiZeng; Kong, XiuYing

    2016-01-01

    Wheat is grown as a staple crop worldwide. It is important to develop an effective genotyping tool for this cereal grain both to identify germplasm diversity and to protect the rights of breeders. Single-nucleotide polymorphism (SNP) genotyping provides a means for developing a practical, rapid, inexpensive and high-throughput assay. Here, we investigated SNPs as robust markers of genetic variation for typing wheat cultivars. We identified SNPs from an array of 9000 across a collection of 429 well-known wheat cultivars grown in China, of which 43 SNP markers with high minor allele frequency and variations discriminated the selected wheat varieties and their wild ancestors. This SNP-based barcode will allow for the rapid and precise identification of wheat germplasm resources and newly released varieties and will further assist in the wheat breeding program. PMID:26985664

  7. Supervised learning-based tagSNP selection for genome-wide disease classifications

    PubMed Central

    Liu, Qingzhong; Yang, Jack; Chen, Zhongxue; Yang, Mary Qu; Sung, Andrew H; Huang, Xudong

    2008-01-01

    Background Comprehensive evaluation of common genetic variations through association of single nucleotide polymorphisms (SNPs) with complex human diseases on the genome-wide scale is an active area in human genome research. One of the fundamental questions in a SNP-disease association study is to find an optimal subset of SNPs with predicting power for disease status. To find that subset while reducing study burden in terms of time and costs, one can potentially reconcile information redundancy from associations between SNP markers. Results We have developed a feature selection method named Supervised Recursive Feature Addition (SRFA). This method combines supervised learning and statistical measures for the chosen candidate features/SNPs to reconcile the redundancy information and, in doing so, improve the classification performance in association studies. Additionally, we have proposed a Support Vector based Recursive Feature Addition (SVRFA) scheme in SNP-disease association analysis. Conclusions We have proposed using SRFA with different statistical learning classifiers and SVRFA for both SNP selection and disease classification and then applying them to two complex disease data sets. In general, our approaches outperform the well-known feature selection method of Support Vector Machine Recursive Feature Elimination and logic regression-based SNP selection for disease classification in genetic association studies. Our study further indicates that both genetic and environmental variables should be taken into account when doing disease predictions and classifications for the most complex human diseases that have gene-environment interactions. PMID:18366619

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

    PubMed

    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

  9. A Unique Primer with an Inosine Chain at the 5′-Terminus Improves the Reliability of SNP Analysis Using the PCR-Amplified Product Length Polymorphism Method

    PubMed Central

    Shojo, Hideki; Tanaka, Mayumi; Takahashi, Ryohei; Kakuda, Tsuneo; Adachi, Noboru

    2015-01-01

    Polymerase chain reaction-amplified product length polymorphism (PCR-APLP) is one of the most convenient and reliable methods for single nucleotide polymorphism (SNP) analysis. This method is based on PCR, but uses allele-specific primers containing SNP sites at the 3′-terminus of each primer. To use this method at least two allele-specific primers and one “counter-primer”, which serves as a common forward or reverse primer of the allele-specific primers, are required. The allele-specific primers have SNP sites at the 3′-terminus, and another primer should have a few non-complementary flaps at the 5′-terminus to detect SNPs by determining the difference of amplicon length by PCR and subsequent electrophoresis. A major disadvantage of the addition of a non-complementary flap is the non-specific annealing of the primer with non-complementary flaps. However, a design principle for avoiding this undesired annealing has not been fully established, therefore, it is often difficult to design effective APLP primers. Here, we report allele-specific primers with an inosine chain at the 5′-terminus for PCR-APLP analysis. This unique design improves the competitiveness of allele-specific primers and the reliability of SNP analysis when using the PCR-APLP method. PMID:26381262

  10. Association of a single nucleotide polymorphism (SNP) of calpain 1 (CAPN1) gene with meat tenderness of yak.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The association of a single nucleotide polymorphism (SNP) of calpain 1 (CAPN1) gene with shear force of 2.54 cm steaks from M. longissimus dorsi from Gannan yaks (Bos grunniens, n=181) was studied. Yaks were harvested at 2, 3, and 4 yr of age (n=51, 59, and 71, respectively), and samples of each yak...

  11. DBDiaSNP: An Open-Source Knowledgebase of Genetic Polymorphisms and Resistance Genes Related to Diarrheal Pathogens.

    PubMed

    Mehla, Kusum; Ramana, Jayashree

    2015-06-01

    Diarrhea is a highly common infection among children, responsible for significant morbidity and mortality rate worldwide. After pneumonia, diarrhea remains the second leading cause of neonatal deaths. Numerous viral, bacterial, and parasitic enteric pathogens are associated with diarrhea. With increasing antibiotic resistance among enteric pathogens, there is an urgent need for global surveillance of the mutations and resistance genes primarily responsible for resistance to antibiotic treatment. Single Nucleotide Polymorphisms are important in this regard as they have a vast potential to be utilized as molecular diagnostics for gene-disease or pharmacogenomics association studies linking genotype to phenotype. DBDiaSNP is a comprehensive repository of mutations and resistance genes among various diarrheal pathogens and hosts to advance breakthroughs that will find applications from development of sequence-based diagnostic tools to drug discovery. It contains information about 946 mutations and 326 resistance genes compiled from literature and various web resources. As of March 2015, it houses various pathogen genes and the mutations responsible for antibiotic resistance. The pathogens include, for example, DEC (Diarrheagenic E.coli), Salmonella spp., Campylobacter spp., Shigella spp., Clostridium difficile, Aeromonas spp., Helicobacter pylori, Entamoeba histolytica, Vibrio cholera, and viruses. It also includes mutations from hosts (e.g., humans, pigs, others) that render them either susceptible or resistant to a certain type of diarrhea. DBDiaSNP is therefore intended as an integrated open access database for researchers and clinicians working on diarrheal diseases. Additionally, we note that the DBDiaSNP is one of the first antibiotic resistance databases for the diarrheal pathogens covering mutations and resistance genes that have clinical relevance from a broad range of pathogens and hosts. For future translational research involving integrative biology and

  12. Varietal identification of tea (Camellia sinensis) using nanofluidic array of single nucleotide polymorphism (SNP) markers

    PubMed Central

    Fang, Wan-Ping; Meinhardt, Lyndel W; Tan, Hua-Wei; Zhou, Lin; Mischke, Sue; Zhang, Dapeng

    2014-01-01

    Apart from water, tea is the world’s most widely consumed beverage. Tea is produced in more than 50 countries with an annual production of approximately 4.7 million tons. The market segment for specialty tea has been expanding rapidly owing to increased demand, resulting in higher revenues and profits for tea growers and the industry. Accurate varietal identification is critically important to ensure traceability and authentication of premium tea products, which in turn contribute to on-farm conservation of tea genetic diversity. Using a set of single nucleotide polymorphism (SNP) markers developed from the expressed sequence tag (EST) database of Camilla senensis, we genotyped deoxyribonucleic acid (DNA) samples extracted from a diverse group of tea varieties, including both fresh and processed commercial loose-leaf teas. The validation led to the designation of 60 SNPs that unambiguously identified all 40 tested tea varieties with high statistical rigor (p<0.0001). Varietal authenticity and genetic relationships among the analyzed cultivars were further characterized by ordination and Bayesian clustering analysis. These SNP markers, in combination with a high-throughput genotyping protocol, effectively established and verified specific DNA fingerprints for all tested tea varieties. This method provides a powerful tool for variety authentication and quality control for the tea industry. It is also highly useful for the management of tea genetic resources and breeding, where accurate and efficient genotype identification is essential. PMID:26504544

  13. Strategies for single nucleotide polymorphism (SNP) genotyping to enhance genotype imputation in Gyr (Bos indicus) dairy cattle: Comparison of commercially available SNP chips.

    PubMed

    Boison, S A; Santos, D J A; Utsunomiya, A H T; Carvalheiro, R; Neves, H H R; O'Brien, A M Perez; Garcia, J F; Sölkner, J; da Silva, M V G B

    2015-07-01

    Genotype imputation is widely used as a cost-effective strategy in genomic evaluation of cattle. Key determinants of imputation accuracies, such as linkage disequilibrium patterns, marker densities, and ascertainment bias, differ between Bos indicus and Bos taurus breeds. Consequently, there is a need to investigate effectiveness of genotype imputation in indicine breeds. Thus, the objective of the study was to investigate strategies and factors affecting the accuracy of genotype imputation in Gyr (Bos indicus) dairy cattle. Four imputation scenarios were studied using 471 sires and 1,644 dams genotyped on Illumina BovineHD (HD-777K; San Diego, CA) and BovineSNP50 (50K) chips, respectively. Scenarios were based on which reference high-density single nucleotide polymorphism (SNP) panel (HDP) should be adopted [HD-777K, 50K, and GeneSeek GGP-75Ki (Lincoln, NE)]. Depending on the scenario, validation animals had their genotypes masked for one of the lower-density panels: Illumina (3K, 7K, and 50K) and GeneSeek (SGGP-20Ki and GGP-75Ki). We randomly selected 171 sires as reference and 300 as validation for all the scenarios. Additionally, all sires were used as reference and the 1,644 dams were imputed for validation. Genotypes of 98 individuals with 4 and more offspring were completely masked and imputed. Imputation algorithms FImpute and Beagle v3.3 and v4 were used. Imputation accuracies were measured using the correlation and allelic correct rate. FImpute resulted in highest accuracies, whereas Beagle 3.3 gave the least-accurate imputations. Accuracies evaluated as correlation (allelic correct rate) ranged from 0.910 (0.942) to 0.961 (0.974) using 50K as HDP and with 3K (7K) as low-density panels. With GGP-75Ki as HDP, accuracies were moderate for 3K, 7K, and 50K, but high for SGGP-20Ki. The use of HD-777K as HDP resulted in accuracies of 0.888 (3K), 0.941 (7K), 0.980 (SGGP-20Ki), 0.982 (50K), and 0.993 (GGP-75Ki). Ungenotyped individuals were imputed with an

  14. SNP-based high density genetic map and mapping of btwd1 dwarfing gene in barley

    PubMed Central

    Ren, Xifeng; Wang, Jibin; Liu, Lipan; Sun, Genlou; Li, Chengdao; Luo, Hong; Sun, Dongfa

    2016-01-01

    A high-density linkage map is a valuable tool for functional genomics and breeding. A newly developed sequence-based marker technology, restriction site associated DNA (RAD) sequencing, has been proven to be powerful for the rapid discovery and genotyping of genome-wide single nucleotide polymorphism (SNP) markers and for the high-density genetic map construction. The objective of this research was to construct a high-density genetic map of barley using RAD sequencing. 1894 high-quality SNP markers were developed and mapped onto all seven chromosomes together with 68 SSR markers. These 1962 markers constituted a total genetic length of 1375.8 cM and an average of 0.7 cM between adjacent loci. The number of markers within each linkage group ranged from 209 to 396. The new recessive dwarfing gene btwd1 in Huaai 11 was mapped onto the high density linkage maps. The result showed that the btwd1 is positioned between SNP marks 7HL_6335336 and 7_249275418 with a genetic distance of 0.9 cM and 0.7 cM on chromosome 7H, respectively. The SNP-based high-density genetic map developed and the dwarfing gene btwd1 mapped in this study provide critical information for position cloning of the btwd1 gene and molecular breeding of barley. PMID:27530597

  15. SNP-based high density genetic map and mapping of btwd1 dwarfing gene in barley.

    PubMed

    Ren, Xifeng; Wang, Jibin; Liu, Lipan; Sun, Genlou; Li, Chengdao; Luo, Hong; Sun, Dongfa

    2016-01-01

    A high-density linkage map is a valuable tool for functional genomics and breeding. A newly developed sequence-based marker technology, restriction site associated DNA (RAD) sequencing, has been proven to be powerful for the rapid discovery and genotyping of genome-wide single nucleotide polymorphism (SNP) markers and for the high-density genetic map construction. The objective of this research was to construct a high-density genetic map of barley using RAD sequencing. 1894 high-quality SNP markers were developed and mapped onto all seven chromosomes together with 68 SSR markers. These 1962 markers constituted a total genetic length of 1375.8 cM and an average of 0.7 cM between adjacent loci. The number of markers within each linkage group ranged from 209 to 396. The new recessive dwarfing gene btwd1 in Huaai 11 was mapped onto the high density linkage maps. The result showed that the btwd1 is positioned between SNP marks 7HL_6335336 and 7_249275418 with a genetic distance of 0.9 cM and 0.7 cM on chromosome 7H, respectively. The SNP-based high-density genetic map developed and the dwarfing gene btwd1 mapped in this study provide critical information for position cloning of the btwd1 gene and molecular breeding of barley. PMID:27530597

  16. Incorporation of Personal Single Nucleotide Polymorphism (SNP) Data into a National Level Electronic Health Record for Disease Risk Assessment, Part 2: The Incorporation of SNP into the National Health Information System of Turkey

    PubMed Central

    Beyan, Timur

    2014-01-01

    Background A personalized medicine approach provides opportunities for predictive and preventive medicine. Using genomic, clinical, environmental, and behavioral data, the tracking and management of individual wellness is possible. A prolific way to carry this personalized approach into routine practices can be accomplished by integrating clinical interpretations of genomic variations into electronic medical record (EMR)s/electronic health record (EHR)s systems. Today, various central EHR infrastructures have been constituted in many countries of the world, including Turkey. Objective As an initial attempt to develop a sophisticated infrastructure, we have concentrated on incorporating the personal single nucleotide polymorphism (SNP) data into the National Health Information System of Turkey (NHIS-T) for disease risk assessment, and evaluated the performance of various predictive models for prostate cancer cases. We present our work as a miniseries containing three parts: (1) an overview of requirements, (2) the incorporation of SNP into the NHIS-T, and (3) an evaluation of SNP data incorporated into the NHIS-T for prostate cancer. Methods For the second article of this miniseries, we have analyzed the existing NHIS-T and proposed the possible extensional architectures. In light of the literature survey and characteristics of NHIS-T, we have proposed and argued opportunities and obstacles for a SNP incorporated NHIS-T. A prototype with complementary capabilities (knowledge base and end-user applications) for these architectures has been designed and developed. Results In the proposed architectures, the clinically relevant personal SNP (CR-SNP) and clinicogenomic associations are shared between central repositories and end-users via the NHIS-T infrastructure. To produce these files, we need to develop a national level clinicogenomic knowledge base. Regarding clinicogenomic decision support, we planned to complete interpretation of these associations on the end

  17. Mouse SNP Miner: an annotated database of mouse functional single nucleotide polymorphisms

    PubMed Central

    Reuveni, Eli; Ramensky, Vasily E; Gross, Cornelius

    2007-01-01

    Background The mapping of quantitative trait loci in rat and mouse has been extremely successful in identifying chromosomal regions associated with human disease-related phenotypes. However, identifying the specific phenotype-causing DNA sequence variations within a quantitative trait locus has been much more difficult. The recent availability of genomic sequence from several mouse inbred strains (including C57BL/6J, 129X1/SvJ, 129S1/SvImJ, A/J, and DBA/2J) has made it possible to catalog DNA sequence differences within a quantitative trait locus derived from crosses between these strains. However, even for well-defined quantitative trait loci (<10 Mb) the identification of candidate functional DNA sequence changes remains challenging due to the high density of sequence variation between strains. Description To help identify functional DNA sequence variations within quantitative trait loci we have used the Ensembl annotated genome sequence to compile a database of mouse single nucleotide polymorphisms (SNPs) that are predicted to cause missense, nonsense, frameshift, or splice site mutations (available at ). For missense mutations we have used the PolyPhen and PANTHER algorithms to predict whether amino acid changes are likely to disrupt protein function. Conclusion We have developed a database of mouse SNPs predicted to cause missense, nonsense, frameshift, and splice-site mutations. Our analysis revealed that 20% and 14% of missense SNPs are likely to be deleterious according to PolyPhen and PANTHER, respectively, and 6% are considered deleterious by both algorithms. The database also provides gene expression and functional annotations from the Symatlas, Gene Ontology, and OMIM databases to further assess candidate phenotype-causing mutations. To demonstrate its utility, we show that Mouse SNP Miner successfully finds a previously identified candidate SNP in the taste receptor, Tas1r3, that underlies sucrose preference in the C57BL/6J strain. We also use Mouse

  18. MDM2 SNP309 promoter polymorphism confers risk for hereditary melanoma.

    PubMed

    Thunell, Lena K; Bivik, Cecilia; Wäster, Petra; Fredrikson, Mats; Stjernström, Annika; Synnerstad, Ingrid; Rosdahl, Inger; Enerbäck, Charlotta

    2014-06-01

    The p53 pathway regulates stress response, and variations in p53, MDM2, and MDM4 may predispose an individual to tumor development. The aim of this study was to study the impact of genetic variation on sporadic and hereditary melanoma. We have analyzed a combination of three functionally relevant variants of the p53 pathway in 258 individuals with sporadic malignant melanomas, 50 with hereditary malignant melanomas, and 799 healthy controls. Genotyping was performed by PCR-restriction fragment length polymorphism, pyrosequencing, and allelic discrimination. We found an increased risk for hereditary melanoma in MDM2 GG homozygotes, which was more pronounced among women (P=0.035). In the event of pairwise combinations of the single nucleotide polymorphisms, a risk elevation was shown for MDM2 GG homozygotes/p53 wild-type Arg in hereditary melanoma (P=0.01). Individuals with sporadic melanomas of the superficial spreading type, including melanoma in situ, showed a slightly higher frequency of the MDM2 GG genotype compared with those with nodular melanomas (P=0.04). The dysplastic nevus phenotype, present in the majority of our hereditary melanoma cases and also in some sporadic cases, further enhanced the effect of the MDM2 GG genotype on melanoma risk (P=0.005). In conclusion, the results show an association between MDM2 SNP309 and an increased risk for hereditary melanoma, especially among women. Analysis of sporadic melanoma also shows an association between MDM2 and the superficial spreading melanoma subtype, as well as an association with the presence of dysplastic nevi in sporadic melanoma. PMID:24625390

  19. SNP Discovery by Illumina-Based Transcriptome Sequencing of the Olive and the Genetic Characterization of Turkish Olive Genotypes Revealed by AFLP, SSR and SNP Markers

    PubMed Central

    Kaya, Hilal Betul; Cetin, Oznur; Kaya, Hulya; Sahin, Mustafa; Sefer, Filiz; Kahraman, Abdullah; Tanyolac, Bahattin

    2013-01-01

    Background The olive tree (Olea europaea L.) is a diploid (2n = 2x = 46) outcrossing species mainly grown in the Mediterranean area, where it is the most important oil-producing crop. Because of its economic, cultural and ecological importance, various DNA markers have been used in the olive to characterize and elucidate homonyms, synonyms and unknown accessions. However, a comprehensive characterization and a full sequence of its transcriptome are unavailable, leading to the importance of an efficient large-scale single nucleotide polymorphism (SNP) discovery in olive. The objectives of this study were (1) to discover olive SNPs using next-generation sequencing and to identify SNP primers for cultivar identification and (2) to characterize 96 olive genotypes originating from different regions of Turkey. Methodology/Principal Findings Next-generation sequencing technology was used with five distinct olive genotypes and generated cDNA, producing 126,542,413 reads using an Illumina Genome Analyzer IIx. Following quality and size trimming, the high-quality reads were assembled into 22,052 contigs with an average length of 1,321 bases and 45 singletons. The SNPs were filtered and 2,987 high-quality putative SNP primers were identified. The assembled sequences and singletons were subjected to BLAST similarity searches and annotated with a Gene Ontology identifier. To identify the 96 olive genotypes, these SNP primers were applied to the genotypes in combination with amplified fragment length polymorphism (AFLP) and simple sequence repeats (SSR) markers. Conclusions/Significance This study marks the highest number of SNP markers discovered to date from olive genotypes using transcriptome sequencing. The developed SNP markers will provide a useful source for molecular genetic studies, such as genetic diversity and characterization, high density quantitative trait locus (QTL) analysis, association mapping and map-based gene cloning in the olive. High levels of

  20. BM-SNP: A Bayesian Model for SNP Calling Using High Throughput Sequencing Data.

    PubMed

    Xu, Yanxun; Zheng, Xiaofeng; Yuan, Yuan; Estecio, Marcos R; Issa, Jean-Pierre; Qiu, Peng; Ji, Yuan; Liang, Shoudan

    2014-01-01

    A single-nucleotide polymorphism (SNP) is a sole base change in the DNA sequence and is the most common polymorphism. Detection and annotation of SNPs are among the central topics in biomedical research as SNPs are believed to play important roles on the manifestation of phenotypic events, such as disease susceptibility. To take full advantage of the next-generation sequencing (NGS) technology, we propose a Bayesian approach, BM-SNP, to identify SNPs based on the posterior inference using NGS data. In particular, BM-SNP computes the posterior probability of nucleotide variation at each covered genomic position using the contents and frequency of the mapped short reads. The position with a high posterior probability of nucleotide variation is flagged as a potential SNP. We apply BM-SNP to two cell-line NGS data, and the results show a high ratio of overlap ( >95 percent) with the dbSNP database. Compared with MAQ, BM-SNP identifies more SNPs that are in dbSNP, with higher quality. The SNPs that are called only by BM-SNP but not in dbSNP may serve as new discoveries. The proposed BM-SNP method integrates information from multiple aspects of NGS data, and therefore achieves high detection power. BM-SNP is fast, capable of processing whole genome data at 20-fold average coverage in a short amount of time. PMID:26357041

  1. Single Nucleotide Polymorphism (SNP) Arrays and Unexpected Consanguinity: Considerations for Clinicians When Returning Results to Families

    PubMed Central

    Delgado, Fernanda; Tabor, Holly K.; Chow, Penny M.; Conta, Jessie H.; Feldman, Kenneth W.; Tsuchiya, Karen D.; Beck, Anita E.

    2014-01-01

    Purpose The broad use of SNP microarrays has increased identification of unexpected consanguinity. Therefore, guidelines to address reporting of consanguinity have been published for clinical laboratories. Because no such guidelines exist for clinicians, we describe a case and present recommendations for clinicians to disclose unexpected consanguinity to families. Methods In a boy with multiple endocrine abnormalities and structural birth defects, SNP array analysis revealed ~23% autosomal homozygosity suggestive of a 1st-degree parental relationship. We assembled an interdisciplinary healthcare team, planned the most appropriate way to discuss results of the SNP array with the adult mother including the possibility of multiple autosomal recessive disorders in her child, and finally met with her as a team. Results From these discussions, we developed four major considerations for clinicians returning results of unexpected consanguinity, all guided by the child’s best interests: 1) ethical and legal obligations for reporting possible abuse, 2) preservation of the clinical relationship, 3) attention to justice and psychosocial challenges, and 4) utilization of the SNP array results to guide further testing. Conclusion As SNP arrays become a common clinical diagnostic tool, clinicians can use this framework to return results of unexpected consanguinity to families in a supportive and productive manner. PMID:25232848

  2. Incorporation of Personal Single Nucleotide Polymorphism (SNP) Data into a National Level Electronic Health Record for Disease Risk Assessment, Part 3: An Evaluation of SNP Incorporated National Health Information System of Turkey for Prostate Cancer

    PubMed Central

    Beyan, Timur

    2014-01-01

    Background A personalized medicine approach provides opportunities for predictive and preventive medicine. Using genomic, clinical, environmental, and behavioral data, the tracking and management of individual wellness is possible. A prolific way to carry this personalized approach into routine practices can be accomplished by integrating clinical interpretations of genomic variations into electronic medical records (EMRs)/electronic health records (EHRs). Today, various central EHR infrastructures have been constituted in many countries of the world, including Turkey. Objective As an initial attempt to develop a sophisticated infrastructure, we have concentrated on incorporating the personal single nucleotide polymorphism (SNP) data into the National Health Information System of Turkey (NHIS-T) for disease risk assessment, and evaluated the performance of various predictive models for prostate cancer cases. We present our work as a three part miniseries: (1) an overview of requirements, (2) the incorporation of SNP data into the NHIS-T, and (3) an evaluation of SNP data incorporated into the NHIS-T for prostate cancer. Methods In the third article of this miniseries, we have evaluated the proposed complementary capabilities (ie, knowledge base and end-user application) with real data. Before the evaluation phase, clinicogenomic associations about increased prostate cancer risk were extracted from knowledge sources, and published predictive genomic models assessing individual prostate cancer risk were collected. To evaluate complementary capabilities, we also gathered personal SNP data of four prostate cancer cases and fifteen controls. Using these data files, we compared various independent and model-based, prostate cancer risk assessment approaches. Results Through the extraction and selection processes of SNP-prostate cancer risk associations, we collected 209 independent associations for increased risk of prostate cancer from the studied knowledge sources. Also

  3. Development and Validation of Single Nucleotide Polymorphism (SNP) Markers from an Expressed Sequence Tag (EST) Database in Olive Flounder (Paralichthys olivaceus)

    PubMed Central

    Kim, Jung Eun; Lee, Young Mee; Lee, Jeong-Ho; Noh, Jae Koo; Kim, Hyun Chul; Park, Choul-Ji; Park, Jong-Won; Kim, Kyung-Kil

    2014-01-01

    To successful molecular breeding, identification and functional characterization of breeding related genes and development of molecular breeding techniques using DNA markers are essential. Although the development of a useful marker is difficult in the aspect of time, cost and effort, many markers are being developed to be used in molecular breeding and developed markers have been used in many fields. Single nucleotide polymorphisms (SNPs) markers were widely used for genomic research and breeding, but has hardly been validated for screening functional genes in olive flounder. We identified single nucleotide polymorphisms (SNPs) from expressed sequence tag (EST) database in olive flounder; out of a total 4,327 ESTs, 693 contigs and 514 SNPs were detected in total EST, and these substitutions include 297 transitions and 217 transversions. As a result, 144 SNP markers were developed on the basis of 514 SNP to selection of useful gene region, and then applied to each of eight wild and culture olive flounder (total 16 samples). In our experimental result, only 32 markers had detected polymorphism in sample, also identified 21 transitions and 11 transversions, whereas indel was not detected in polymorphic SNPs. Heterozygosity of wild and cultured olive flounder using the 32 SNP markers is 0.34 and 0.29, respectively. In conclusion, we identified SNP and polymorphism in olive flounder using newly designed marker, it supports that developed markers are suitable for SNP detection and diversity analysis in olive flounder. The outcome of this study can be basic data for researches for immunity gene and characteristic with SNP. PMID:25949198

  4. A web-based genome browser for 'SNP-aware' assay design

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Human and animal genomes contain an abundance of single nucleotide polymorphisms (SNPs) that are useful for genetic testing. However, the relatively large number of SNPs present in diverse populations can pose serious problems when designing assays. It is important to “mask” some SNP positions so ...

  5. Fast and Rigorous Computation of Gene and Pathway Scores from SNP-Based Summary Statistics

    PubMed Central

    Rueedi, Rico; Kutalik, Zoltán; Bergmann, Sven

    2016-01-01

    Integrating single nucleotide polymorphism (SNP) p-values from genome-wide association studies (GWAS) across genes and pathways is a strategy to improve statistical power and gain biological insight. Here, we present Pascal (Pathway scoring algorithm), a powerful tool for computing gene and pathway scores from SNP-phenotype association summary statistics. For gene score computation, we implemented analytic and efficient numerical solutions to calculate test statistics. We examined in particular the sum and the maximum of chi-squared statistics, which measure the strongest and the average association signals per gene, respectively. For pathway scoring, we use a modified Fisher method, which offers not only significant power improvement over more traditional enrichment strategies, but also eliminates the problem of arbitrary threshold selection inherent in any binary membership based pathway enrichment approach. We demonstrate the marked increase in power by analyzing summary statistics from dozens of large meta-studies for various traits. Our extensive testing indicates that our method not only excels in rigorous type I error control, but also results in more biologically meaningful discoveries. PMID:26808494

  6. Fast and Rigorous Computation of Gene and Pathway Scores from SNP-Based Summary Statistics.

    PubMed

    Lamparter, David; Marbach, Daniel; Rueedi, Rico; Kutalik, Zoltán; Bergmann, Sven

    2016-01-01

    Integrating single nucleotide polymorphism (SNP) p-values from genome-wide association studies (GWAS) across genes and pathways is a strategy to improve statistical power and gain biological insight. Here, we present Pascal (Pathway scoring algorithm), a powerful tool for computing gene and pathway scores from SNP-phenotype association summary statistics. For gene score computation, we implemented analytic and efficient numerical solutions to calculate test statistics. We examined in particular the sum and the maximum of chi-squared statistics, which measure the strongest and the average association signals per gene, respectively. For pathway scoring, we use a modified Fisher method, which offers not only significant power improvement over more traditional enrichment strategies, but also eliminates the problem of arbitrary threshold selection inherent in any binary membership based pathway enrichment approach. We demonstrate the marked increase in power by analyzing summary statistics from dozens of large meta-studies for various traits. Our extensive testing indicates that our method not only excels in rigorous type I error control, but also results in more biologically meaningful discoveries. PMID:26808494

  7. Association between MDM2 SNP309 T>G polymorphism and the risk of bladder cancer: new data in a Chinese population and an updated meta-analysis

    PubMed Central

    Xie, Linguo; Sun, Yan; Chen, Tao; Tian, Dawei; Li, Yujuan; Zhang, Yu; Ding, Na; Shen, Zhonghua; Xu, Hao; Nian, Xuewu; Sha, Nan; Han, Ruifa; Hu, Hailong; Wu, Changli

    2015-01-01

    Objective Human murine double minute 2 protein (MDM2) is mainly a negative regulator of p53 tumor suppressor pathway. We aimed to investigate the association between MDM2 SNP309 polymorphism and bladder cancer risk. Methods A total of 535 bladder cancer patients and 649 health controls were recruited for our study. MDM2 SNP309 T>G polymorphism was genotyped by polymerase chain reaction-ligase detection reaction method. Logistic regression was used to analyze the relationship between the genotype and susceptibility of bladder cancer. Kaplan–Meier estimates and log-rank test were obtained to analyze the association between the genotype and risk of recrudesce in nonmuscle-invasive bladder cancer patients. A multivariable Cox proportional hazards model was fitted to identify independent prognostic factors. To further investigate the association, we conducted a meta-analysis including six studies. Results The frequency of the MDM2 SNP309 T>G polymorphism showed no significant difference between cases and controls (all P>0.05). In the stratification analysis, the results showed that G allele carriers were prone to have a significant decrease in risk of low-grade bladder cancer (adjusted odds ratio: 0.613, 95% confidence interval: 0.427–0.881), and G variant was associated with a significantly reduced risk of recurrence in nonmuscle-invasive bladder cancer patients with or without chemotherapy (P<0.05). The results of the meta-analysis showed that G allele and GG genotype of MDM2 SNP309 polymorphism were significantly associated with increased risk of bladder cancer in Caucasians (both P<0.05), and no association was observed in total populations and Asians (P>0.05). Conclusion MDM2 SNP309 T>G polymorphism has no influence on bladder cancer risk in Asians, but this single nucleotide polymorphism may be associated with genetic susceptibility of bladder cancer among Caucasians. PMID:26672516

  8. Population-standardized genetic risk score: the SNP-based method of choice for inherited risk assessment of prostate cancer.

    PubMed

    Conran, Carly A; Na, Rong; Chen, Haitao; Jiang, Deke; Lin, Xiaoling; Zheng, S Lilly; Brendler, Charles B; Xu, Jianfeng

    2016-01-01

    Several different approaches are available to clinicians for determining prostate cancer (PCa) risk. The clinical validity of various PCa risk assessment methods utilizing single nucleotide polymorphisms (SNPs) has been established; however, these SNP-based methods have not been compared. The objective of this study was to compare the three most commonly used SNP-based methods for PCa risk assessment. Participants were men (n = 1654) enrolled in a prospective study of PCa development. Genotypes of 59 PCa risk-associated SNPs were available in this cohort. Three methods of calculating SNP-based genetic risk scores (GRSs) were used for the evaluation of individual disease risk such as risk allele count (GRS-RAC), weighted risk allele count (GRS-wRAC), and population-standardized genetic risk score (GRS-PS). Mean GRSs were calculated, and performances were compared using area under the receiver operating characteristic curve (AUC) and positive predictive value (PPV). All SNP-based methods were found to be independently associated with PCa (all P < 0.05; hence their clinical validity). The mean GRSs in men with or without PCa using GRS-RAC were 55.15 and 53.46, respectively, using GRS-wRAC were 7.42 and 6.97, respectively, and using GRS-PS were 1.12 and 0.84, respectively (all P < 0.05 for differences between patients with or without PCa). All three SNP-based methods performed similarly in discriminating PCa from non-PCa based on AUC and in predicting PCa risk based on PPV (all P > 0.05 for comparisons between the three methods), and all three SNP-based methods had a significantly higher AUC than family history (all P < 0.05). Results from this study suggest that while the three most commonly used SNP-based methods performed similarly in discriminating PCa from non-PCa at the population level, GRS-PS is the method of choice for risk assessment at the individual level because its value (where 1.0 represents average population risk) can be easily interpreted regardless

  9. Population-standardized genetic risk score: the SNP-based method of choice for inherited risk assessment of prostate cancer

    PubMed Central

    Conran, Carly A; Na, Rong; Chen, Haitao; Jiang, Deke; Lin, Xiaoling; Zheng, S Lilly; Brendler, Charles B; Xu, Jianfeng

    2016-01-01

    Several different approaches are available to clinicians for determining prostate cancer (PCa) risk. The clinical validity of various PCa risk assessment methods utilizing single nucleotide polymorphisms (SNPs) has been established; however, these SNP-based methods have not been compared. The objective of this study was to compare the three most commonly used SNP-based methods for PCa risk assessment. Participants were men (n = 1654) enrolled in a prospective study of PCa development. Genotypes of 59 PCa risk-associated SNPs were available in this cohort. Three methods of calculating SNP-based genetic risk scores (GRSs) were used for the evaluation of individual disease risk such as risk allele count (GRS-RAC), weighted risk allele count (GRS-wRAC), and population-standardized genetic risk score (GRS-PS). Mean GRSs were calculated, and performances were compared using area under the receiver operating characteristic curve (AUC) and positive predictive value (PPV). All SNP-based methods were found to be independently associated with PCa (all P < 0.05; hence their clinical validity). The mean GRSs in men with or without PCa using GRS-RAC were 55.15 and 53.46, respectively, using GRS-wRAC were 7.42 and 6.97, respectively, and using GRS-PS were 1.12 and 0.84, respectively (all P < 0.05 for differences between patients with or without PCa). All three SNP-based methods performed similarly in discriminating PCa from non-PCa based on AUC and in predicting PCa risk based on PPV (all P > 0.05 for comparisons between the three methods), and all three SNP-based methods had a significantly higher AUC than family history (all P < 0.05). Results from this study suggest that while the three most commonly used SNP-based methods performed similarly in discriminating PCa from non-PCa at the population level, GRS-PS is the method of choice for risk assessment at the individual level because its value (where 1.0 represents average population risk) can be easily interpreted regardless

  10. Leptin receptor (LEPR) SNP polymorphisms in HELLP syndrome patients determined by quantitative real-time PCR and melting curve analysis

    PubMed Central

    2010-01-01

    Background Several studies have shown overexpression of leptin in microarray experiments in pre-eclampsia (PE) and in hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. We decided to study four leptin receptor (LEPR) SNP polymorphisms in HELLP syndrome patients by using quantitative real-time PCR and melting curve analysis. Methods DNA was isolated from blood samples from 83 normotensive pregnant women and 75 HELLP syndrome patients. Four SNPs, LEPR c.326A>G (K109), LEPR c.668A>G (Q223R), LEPR c.1968G>C (K656N) and LEPR c.3024A>G (S1008) were determined by quantitative real-time PCR and melting curve analysis. Investigators were blinded to clinical outcomes. Results LEPR c.326A>G, LEPR c.668A>G, LEPR c.1968G>C and LEPR c.3024A>G allele, genotype and haplotype polymorphisms were not different in HELLP syndrome patients and normotensive healthy pregnants. There were strong linkage disequilibrium (LD) between loci c.326A>G and c.6687A>G (D' = 0.974), and c.668A>G and c.1968G>C (D' = 0.934), and c.326A>G and c.1968G>C (D' = 0.885), and c.1968G>C and c.3024A>G (D' = 1.0). However, linkages of c.3024A>G with c.668A>G (D' = 0.111) and c.326A>G (D' = 0.398) were weak. The Hardy-Weinberg equilibrium was observed for all polymorphisms. However the LEPR c.326A>G AG genotype was twice more frequent and the (AG AG GG AG) haplotype was three times more frequent in HELLP syndrome patients. The introduced quantitative real-time PCR combined with melting curve analysis is a fast and reliable method for the determination of LEPR SNPs. Conclusion Although certain LEPR haplotypes are more frequent in HELLP syndrome, we conclude that there is no compelling evidence that the four studied LEPR SNP polymorphisms associated with the development of HELLP syndrome. PMID:20149225

  11. A MEMS-Based Approach to Single Nucleotide Polymorphism Genotyping

    PubMed Central

    Zhu, Jing; Palla, Mirkó; Ronca, Stefano; Warpner, Ronald; Ju, Jingyue; Lin, Qiao

    2014-01-01

    Genotyping of single nucleotide polymorphisms (SNPs) allows diagnosis of human genetic disorders associated with single base mutations. Conventional SNP genotyping methods are capable of providing either accurate or high-throughput detection, but are still labor-, time-, and resource-intensive. Microfluidics has been applied to SNP detection to provide fast, low-cost, and automated alternatives, although these applications are still limited by either accuracy or throughput issues. To address this challenge, we present a MEMS-based SNP genotyping approach that uses solid-phase-based reactions in a single microchamber on a temperature control chip. Polymerase chain reaction (PCR), allele specific single base extension (SBE), and desalting on microbeads are performed in the microchamber, which is coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to analyze the SBE product. Experimental results from genotyping of the SNP on exon 1 of the HBB gene, which causes sickle cell anemia, demonstrate the potential of the device for rapid, accurate, multiplexed and high-throughput detection of SNPs. PMID:24729659

  12. SNP genotyping by heteroduplex analysis.

    PubMed

    Paniego, Norma; Fusari, Corina; Lia, Verónica; Puebla, Andrea

    2015-01-01

    Heteroduplex-based genotyping methods have proven to be technologically effective and economically efficient for low- to medium-range throughput single-nucleotide polymorphism (SNP) determination. In this chapter we describe two protocols that were successfully applied for SNP detection and haplotype analysis of candidate genes in association studies. The protocols involve (1) enzymatic mismatch cleavage with endonuclease CEL1 from celery, associated with fragment separation using capillary electrophoresis (CEL1 cleavage), and (2) differential retention of the homo/heteroduplex DNA molecules under partial denaturing conditions on ion pair reversed-phase liquid chromatography (dHPLC). Both methods are complementary since dHPLC is more versatile than CEL1 cleavage for identifying multiple SNP per target region, and the latter is easily optimized for sequences with fewer SNPs or small insertion/deletion polymorphisms. Besides, CEL1 cleavage is a powerful method to localize the position of the mutation when fragment resolution is done using capillary electrophoresis. PMID:25373754

  13. Murine Double Minute 2 SNP T309G Polymorphism and Urinary Tract Cancer Risk: A Meta-Analysis.

    PubMed

    Ding, Hui; Dai, Yu; Ning, Zhongyun; Fan, Ning; Wang, Zhiping; Li, Pei; Zhang, Liyuan; Tao, Yan; Wang, Hanzhang

    2016-03-01

    Urinary tract cancer is a common cause of cancer-related death. The etiology and pathogenesis of urinary tract cancer remain unclear, with genetic and epigenetic factors playing an important role. Studies of the polymorphism of murine double minute 2 (MDM2) have shown inconclusive trends in the risk of urinary tract cancer.To clarify this inconsistency, we conducted updated meta-analyses to evaluate the role of MDM2 T309G polymorphism in urinary tract cancer susceptibility.Data sources were Pubmed (1966-May 2015), Chinese biomedicine literature database (1978-May 2015), and hand searching of the reference lists of included studies:(1) research categories case-control study or a nested case-control study; (2) information evaluating the association between the MDM2 SNP309 and urinary tract cancer risk; (3) studies with sufficient data to perform a meta-analysis.It included the use of odds ratios (ORs) to assess the strength of the association, and 95% confidence intervals (CIs) give a sense of the precision of the estimate. We used I for the assessment of between-study heterogeneity, and publication bias was assessed using the funnel plot and the Egger test. Statistical analyses were performed by Review Manage, version 5.0 and Stata 11.0.A total of 18 studies met the eligibility criteria and were included in our analyses. Overall, there was no statistical association between MDM2 SNP309 and prostate cancer risk for the allele contrast, the GG genotype, the recessive genetic model, the dominant genetic model, and prostate cancer risk in all subjects (OR = 0.96, 95% CI 0.87-1.05, P = 0.36; OR = 0.93, 95% CI 0.75-1.15, P = 0.50; OR = 1.00, 95% CI 0.87-1.15, P = 0.99; OR = 0.93, 95% CI 0.80-1.07, P = 0.30), and between MDM2 SNP309 and bladder cancer risk (the allele contrast: OR = 1.06, 95% CI 0.89-1.27, P = 0.50; the GG genotype: OR = 1.12, 95% CI 0.79-1.61, P = 0.52; the dominant genetic model: OR = 1.03, 95% CI 0

  14. Rapid Identification of Ginseng Cultivars (Panax ginseng Meyer) Using Novel SNP-Based Probes

    PubMed Central

    Jo, Ick-Hyun; Bang, Kyong Hwan; Kim, Young-Chang; Lee, Jei-Wan; Seo, A-Yeon; Seong, Bong-Jae; Kim, Hyun-Ho; Kim, Dong-Hwi; Cha, Seon-Woo; Cho, Yong-Gu; Kim, Hong-Sig

    2011-01-01

    In order to develop a novel system for the discrimination of five ginseng cultivars (Panax ginseng Meyer), single nucleotide polymorphism (SNP) genotyping assays with real-time polymerase chain reaction were conducted. Nucleotide substitution in gDNA library clones of P. ginseng cv. Yunpoong was targeted for the SNP genotyping assay. From these SNP sites, a set of modified SNP specific fluorescence probes (PGP74, PGP110, and PGP130) and novel primer sets have been developed to distinguish among five ginseng cultivars. The combination of the SNP type of the five cultivars, Chungpoong, Yunpoong, Gopoong, Kumpoong, and Sunpoong, was identified as ‘ATA’, ‘GCC’, ‘GTA’, ‘GCA’, and ‘ACC’, respectively. This study represents the first report of the identification of ginseng cultivars by fluorescence probes. An SNP genotyping assay using fluorescence probes could prove useful for the identification of ginseng cultivars and ginseng seed management systems and guarantee the purity of ginseng seed. PMID:23717098

  15. 1 + 1 = 3: Development and validation of a SNP-based algorithm to identify genetic contributions from three distinct inbred mouse strains.

    PubMed

    Gorham, James D; Ranson, Matthew S; Smith, Janebeth C; Gorham, Beverly J; Muirhead, Kristen-Ashley

    2012-12-01

    State-of-the-art, genome-wide assessment of mouse genetic background uses single nucleotide polymorphism (SNP) PCR. As SNP analysis can use multiplex testing, it is amenable to high-throughput analysis and is the preferred method for shared resource facilities that offer genetic background assessment of mouse genomes. However, a typical individual SNP query yields only two alleles (A vs. B), limiting the application of this methodology to distinguishing contributions from no more than two inbred mouse strains. By contrast, simple sequence length polymorphism (SSLP) analysis yields multiple alleles but is not amenable to high-throughput testing. We sought to devise a SNP-based technique to identify donor strain origins when three distinct mouse strains potentially contribute to the genetic makeup of an individual mouse. A computational approach was used to devise a three-strain analysis (3SA) algorithm that would permit identification of three genetic backgrounds while still using a binary-output SNP platform. A panel of 15 mosaic mice with contributions from BALB/c, C57Bl/6, and DBA/2 genetic backgrounds was bred and analyzed using a genome-wide SNP panel using 1449 markers. The 3SA algorithm was applied and then validated using SSLP. The 3SA algorithm assigned 85% of 1449 SNPs as informative for the C57Bl/6, BALB/c, or DBA/2 backgrounds, respectively. Testing the panel of 15 F2 mice, the 3SA algorithm predicted donor strain origins genome-wide. Donor strain origins predicted by the 3SA algorithm correlated perfectly with results from individual SSLP markers located on five different chromosomes (n=70 tests). We have established and validated an analysis algorithm based on binary SNP data that can successfully identify the donor strain origins of chromosomal regions in mice that are bred from three distinct inbred mouse strains. PMID:23204929

  16. Single nucleotide polymorphism (SNP) variation of wolves (Canis lupus) in Southeast Alaska and comparison with wolves, dogs, and coyotes in North America.

    PubMed

    Cronin, Matthew A; Cánovas, Angela; Bannasch, Danika L; Oberbauer, Anita M; Medrano, Juan F

    2015-01-01

    There is considerable interest in the genetics of wolves (Canis lupus) because of their close relationship to domestic dogs (C. familiaris) and the need for informed conservation and management. This includes wolf populations in Southeast Alaska for which we determined genotypes of 305 wolves at 173662 single nucleotide polymorphism (SNP) loci. After removal of invariant and linked SNP, 123801 SNP were used to quantify genetic differentiation of wolves in Southeast Alaska and wolves, coyotes (C. latrans), and dogs from other areas in North America. There is differentiation of SNP allele frequencies between the species (wolves, coyotes, and dogs), although differentiation is relatively low between some wolf and coyote populations. There are varying levels of differentiation among populations of wolves, including low differentiation of wolves in interior Alaska, British Columbia, and the northern US Rocky Mountains. There is considerable differentiation of SNP allele frequencies of wolves in Southeast Alaska from wolves in other areas. However, wolves in Southeast Alaska are not a genetically homogeneous group and there are comparable levels of genetic differentiation among areas within Southeast Alaska and between Southeast Alaska and other geographic areas. SNP variation and other genetic data are discussed regarding taxonomy and management. PMID:25429025

  17. Conditions for the validity of SNP-based heritability estimation

    PubMed Central

    2014-01-01

    The heritability of a trait (h2) is the proportion of its population variance caused by genetic differences, and estimates of this parameter are important for interpreting the results of genome-wide association studies (GWAS). In recent years, researchers have adopted a novel method for estimating a lower bound on heritability directly from GWAS data that uses realized genetic similarities between nominally unrelated individuals. The quantity estimated by this method is purported to be the contribution to heritability that could in principle be recovered from association studies employing the given panel of SNPs (hSNP2). Thus far, the validity of this approach has mostly been tested empirically. Here, we provide a mathematical explication and show that the method should remain a robust means of obtaining hSNP2 SNP under circumstances wider than those under which it has so far been derived. PMID:24744256

  18. Development of a web services based system for dissemination of single nucleotide polymorphism data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Single nucleotide polymorphisms (SNPs) can be used to generate DNA-based fingerprints for individual identification. The efficiency of DNA fingerprinting is greatest when the frequency of both SNP alleles is near 0.50. A number of SNPs have been identified in cattle populations with minor allele f...

  19. Identification of Swedish mosquitoes based on molecular barcoding of the COI gene and SNP analysis.

    PubMed

    Engdahl, Cecilia; Larsson, Pär; Näslund, Jonas; Bravo, Mayra; Evander, Magnus; Lundström, Jan O; Ahlm, Clas; Bucht, Göran

    2014-05-01

    Mosquito-borne infectious diseases are emerging in many regions of the world. Consequently, surveillance of mosquitoes and concomitant infectious agents is of great importance for prediction and prevention of mosquito-borne infectious diseases. Currently, morphological identification of mosquitoes is the traditional procedure. However, sequencing of specified genes or standard genomic regions, DNA barcoding, has recently been suggested as a global standard for identification and classification of many different species. Our aim was to develop a genetic method to identify mosquitoes and to study their relationship. Mosquitoes were captured at collection sites in northern Sweden and identified morphologically before the cytochrome c oxidase subunit I (COI) gene sequences of 14 of the most common mosquito species were determined. The sequences obtained were then used for phylogenetic placement, for validation and benchmarking of phenetic classifications and finally to develop a hierarchical PCR-based typing scheme based on single nucleotide polymorphism sites (SNPs) to enable rapid genetic identification, circumventing the need for morphological characterization. The results showed that exact phylogenetic relationships between mosquito taxa were preserved at shorter evolutionary distances, but at deeper levels, they could not be inferred with confidence using COI gene sequence data alone. Fourteen of the most common mosquito species in Sweden were identified by the SNP/PCR-based typing scheme, demonstrating that genetic typing using SNPs of the COI gene is a useful method for identification of mosquitoes with potential for worldwide application. PMID:24215491

  20. Association and CpG SNP analysis of HTR4 polymorphisms with suicidal behavior in subjects with schizophrenia.

    PubMed

    Polsinelli, Gina; Zai, Clement C; Strauss, John; Kennedy, James L; De Luca, Vincenzo

    2013-02-01

    Suicide is a major contributor to the morbidity and mortality rates in schizophrenia. Genetic and epigenetic factors have been reported to modulate the risk for suicide although the precise mechanism and magnitude of these contributions is unknown. Previous research indicates that suicide attempters present abnormalities in the serotonergic system. The present study aimed to identify genetic and epigenetic risk variants of the serotonin 5-HT₄ receptor gene (HTR4) for suicidal behavior. We included 234 subjects diagnosed with schizophrenia. For this purpose, we analyzed 11 markers across HTR4 and performed genotype, haplotype and potential methylation analyses, correcting for clinical covariates and ethnic stratification. Three blocks were revealed from the LD analysis. Haplotypes in Block 3 were significantly associated with suicide attempt. The potential methylation analysis was not significant. Our results suggest that HTR4 polymorphisms may not play a major role in the susceptibility for suicidal behavior in subjects with schizophrenia. Moreover, although not significant, the CpG SNP potential methylation analysis would be informative for future methylation analysis on this gene. PMID:22842674

  1. A genome-wide SNP-based phylogenetic analysis distinguishes different biovars of Brucella suis.

    PubMed

    Sankarasubramanian, Jagadesan; Vishnu, Udayakumar S; Gunasekaran, Paramasamy; Rajendhran, Jeyaprakash

    2016-07-01

    Brucellosis is an important zoonotic disease caused by Brucella spp. Brucella suis is the etiological agent of porcine brucellosis. B. suis is the most genetically diverged species within the genus Brucella. We present the first large-scale B. suis phylogenetic analysis based on an alignment-free k-mer approach of gathering polymorphic sites from whole genome sequences. Genome-wide core-SNP based phylogenetic tree clearly differentiated and discriminated the B. suis biovars and the vaccine strain into different clades. A total of 16,756 SNPs were identified from the genome sequences of 54 B. suis strains. Also, biovar-specific SNPs were identified. The vaccine strain B. suis S2-30 is extensively used in China, which was discriminated from all biovars with the accumulation of the highest number of SNPs. We have also identified the SNPs between B. suis vaccine strain S2-30 and its closest homolog, B. suis biovar 513UK. The highest number of mutations (22) was observed in the phosphomannomutase (pmm) gene essential for the synthesis of O-antigen. Also, mutations were identified in several virulent genes including genes coding for type IV secretion system and the effector proteins, which could be responsible for the attenuated virulence of B. suis S2-30. PMID:27085292

  2. SNP-based pathway enrichment analysis for genome-wide association studies

    PubMed Central

    2011-01-01

    Background Recently we have witnessed a surge of interest in using genome-wide association studies (GWAS) to discover the genetic basis of complex diseases. Many genetic variations, mostly in the form of single nucleotide polymorphisms (SNPs), have been identified in a wide spectrum of diseases, including diabetes, cancer, and psychiatric diseases. A common theme arising from these studies is that the genetic variations discovered by GWAS can only explain a small fraction of the genetic risks associated with the complex diseases. New strategies and statistical approaches are needed to address this lack of explanation. One such approach is the pathway analysis, which considers the genetic variations underlying a biological pathway, rather than separately as in the traditional GWAS studies. A critical challenge in the pathway analysis is how to combine evidences of association over multiple SNPs within a gene and multiple genes within a pathway. Most current methods choose the most significant SNP from each gene as a representative, ignoring the joint action of multiple SNPs within a gene. This approach leads to preferential identification of genes with a greater number of SNPs. Results We describe a SNP-based pathway enrichment method for GWAS studies. The method consists of the following two main steps: 1) for a given pathway, using an adaptive truncated product statistic to identify all representative (potentially more than one) SNPs of each gene, calculating the average number of representative SNPs for the genes, then re-selecting the representative SNPs of genes in the pathway based on this number; and 2) ranking all selected SNPs by the significance of their statistical association with a trait of interest, and testing if the set of SNPs from a particular pathway is significantly enriched with high ranks using a weighted Kolmogorov-Smirnov test. We applied our method to two large genetically distinct GWAS data sets of schizophrenia, one from European

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

    PubMed Central

    2012-01-01

    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 < 0.0001) were found in the schizophrenia GWAS. Our findings identified the possible functions of these SNP loci, and provide the basis for subsequent functional research. Conclusion MirSNP could identify the putative miRNA-related SNPs from GWAS and eQTLs researches and provide the direction for subsequent functional researches. PMID:23173617

  4. Comparative Performance of Single Nucleotide Polymorphism (SNP) and Microsatellite Markers for the Detection of Population Differentiation in Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Putative single nucleotide polymorphisms (SNPs) were identified from contiguous sequences assembled from Diabrotica virgifera virgifera midgut expressed sequence tags (ESTs). Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP)-based assays confirmed variation at 20 biallel...

  5. IL28B Gene Polymorphism SNP rs8099917 Genotype GG Is Associated with HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP) in HTLV-1 Carriers

    PubMed Central

    Luiz, Olinda do Carmo; Malta, Fernanda; Pinho, João Renato Rebello; Gonçalves, Fernanda de Toledo; Duarte, Alberto Jose da Silva; de Oliveira, Augusto Cesar Penalva

    2014-01-01

    Background The polymorphisms of IL28B have been described as important in the pathogenesis of infections caused by some viruses. The aim of this research was to evaluate whether IL28B gene polymorphisms (SNP rs8099917 and SNP rs12979860) are associated with HAM/TSP. Methods The study included 229 subjects, classified according to their neurological status in two groups: Group I (136 asymptomatic HTLV-1 carriers) and Group II (93 HAM/TSP patients). The proviral loads were quantified, and the rs8099917 and rs12979860 SNPs in the region of IL28B-gene were analyzed by StepOnePlus Real-time PCR System. Results A multivariate model analysis, including gender, age, and HTLV-1 DNA proviral load, showed that IL28B polymorphisms were independently associated with HAM/TSP outcome in rs12979860 genotype CT (OR = 2.03; IC95% = 0.96–4.27) and in rs8099917 genotype GG (OR = 7.61; IC95% = 1.82–31.72). Conclusion Subjects with SNP rs8099917 genotype GG and rs12979618 genotype CT may present a distinct immune response against HTLV-1 infection. So, it seems reasonable to suggest that a search for IL28B polymorphisms should be performed for all HTLV-1-infected subjects in order to monitor their risk for disease development; however, since this is the first description of such finding in the literature, we should first replicate this study with more HTLV-1-infected persons to strengthen the evidence already provided by our results. PMID:25233462

  6. SNP-VISTA: An interactive SNP visualization tool

    PubMed Central

    Shah, Nameeta; Teplitsky, Michael V; Minovitsky, Simon; Pennacchio, Len A; Hugenholtz, Philip; Hamann, Bernd; Dubchak, Inna L

    2005-01-01

    Background Recent advances in sequencing technologies promise to provide a better understanding of the genetics of human disease as well as the evolution of microbial populations. Single Nucleotide Polymorphisms (SNPs) are established genetic markers that aid in the identification of loci affecting quantitative traits and/or disease in a wide variety of eukaryotic species. With today's technological capabilities, it has become possible to re-sequence a large set of appropriate candidate genes in individuals with a given disease in an attempt to identify causative mutations. In addition, SNPs have been used extensively in efforts to study the evolution of microbial populations, and the recent application of random shotgun sequencing to environmental samples enables more extensive SNP analysis of co-occurring and co-evolving microbial populations. The program is available at [1]. Results We have developed and present two modifications of an interactive visualization tool, SNP-VISTA, to aid in the analyses of the following types of data: A. Large-scale re-sequence data of disease-related genes for discovery of associated and/or causative alleles (GeneSNP-VISTA). B. Massive amounts of ecogenomics data for studying homologous recombination in microbial populations (EcoSNP-VISTA). The main features and capabilities of SNP-VISTA are: 1) mapping of SNPs to gene structure; 2) classification of SNPs, based on their location in the gene, frequency of occurrence in samples and allele composition; 3) clustering, based on user-defined subsets of SNPs, highlighting haplotypes as well as recombinant sequences; 4) integration of protein evolutionary conservation visualization; and 5) display of automatically calculated recombination points that are user-editable. Conclusion The main strength of SNP-VISTA is its graphical interface and use of visual representations, which support interactive exploration and hence better understanding of large-scale SNP data by the user. PMID

  7. The polymorphisms of P53 codon 72 and MDM2 SNP309 and renal cell carcinoma risk in a low arsenic exposure area

    SciTech Connect

    Huang, Chao-Yuan; Su, Chien-Tien; Chu, Jan-Show; Huang, Shu-Pin; Pu, Yeong-Shiau; Yang, Hsiu-Yuan; Chung, Chi-Jung; Wu, Chia-Chang; Hsueh, Yu-Mei

    2011-12-15

    Our recent study demonstrated the increased risk of renal cell carcinoma (RCC) associated with high urinary total arsenic levels among people living in a low arsenic exposure area. Genomic instability is important in arsenic carcinogenesis. This study evaluated the relationship between the polymorphisms of p53, p21, and MDM2, which plays a role in gene stability, and the arsenic-related RCC risk. Here, we found that p53 Pro/Pro genotype and MDM2 SNP309 GG genotype significantly increased RCC risk compared to the p53 Arg/Arg genotype and MDM2 SNP309 TT genotype. RCC patients with the p53Arg/Arg genotype had a signicantly low percentage of inorganic arsenic, a low percentage of monomethylarsonic acid (MMA), and a high percentage of dimethylarsinic acid (DMA), which indicates efcient arsenic methylation capacity. Subjects with the p53 Arg/Pro + Pro/Pro genotype or MDM2 SNP309 TG + GG genotype, in conjunction with high urinary total arsenic ({>=} 14.02 {mu}g/L), had a signicantly higher RCC risk than those with the p53 Arg/Arg or MDM2 SNP309 TT genotypes and low urinary total arsenic. Taken together, this is the first study to show that a variant genotype of p53 Arg{sup 72}Pro or MDM2 SNP309 may modify the arsenic-related RCC risk even in a non-obvious arsenic exposure area. -- Highlights: Black-Right-Pointing-Pointer Subjects with p53 Pro/Pro or MDM2 GG genotype significantly increased RCC risk. Black-Right-Pointing-Pointer A significant multiplicative joint effect of p53 and p21 on RCC risk. Black-Right-Pointing-Pointer RCC patients with p53 Arg/Arg genotype had efficient arsenic methylation capacity. Black-Right-Pointing-Pointer Joint effect of p53 or MDM2 genotype and high urinary total arsenic on RCC risk.

  8. Single-copy gene based 50 K SNP chip for genetic studies and molecular breeding in rice

    PubMed Central

    Singh, Nisha; Jayaswal, Pawan Kumar; Panda, Kabita; Mandal, Paritra; Kumar, Vinod; Singh, Balwant; Mishra, Shefali; Singh, Yashi; Singh, Renu; Rai, Vandna; Gupta, Anita; Raj Sharma, Tilak; Singh, Nagendra Kumar

    2015-01-01

    Single nucleotide polymorphism (SNP) is the most abundant DNA sequence variation present in plant genomes. Here, we report the design and validation of a unique genic-SNP genotyping chip for genetic and evolutionary studies as well as molecular breeding applications in rice. The chip incorporates 50,051 SNPs from 18,980 different genes spanning 12 rice chromosomes, including 3,710 single-copy (SC) genes conserved between wheat and rice, 14,959 SC genes unique to rice, 194 agronomically important cloned rice genes and 117 multi-copy rice genes. Assays with this chip showed high success rate and reproducibility because of the SC gene based array with no sequence redundancy and cross-hybridisation problems. The usefulness of the chip in genetic diversity and phylogenetic studies of cultivated and wild rice germplasm was demonstrated. Furthermore, its efficacy was validated for analysing background recovery in improved mega rice varieties with submergence tolerance developed through marker-assisted backcross breeding. PMID:26111882

  9. Y-chromosome polymorphisms and ethnic group – a combined STR and SNP approach in a population sample from northern Italy

    PubMed Central

    Cortellini, Venusia; Verzeletti, Andrea; Cerri, Nicoletta; Marino, Alberto; De Ferrari, Francesco

    2013-01-01

    Aim To find an association between Y chromosome polymorphisms and some ethnic groups. Methods Short tandem repeats (STR) and single-nucleotide polymorphisms (SNP) on the Y chromosome were typed in 311 unrelated men from four different ethnic groups – Italians from northern Italy, Albanians, Africans from the Maghreb region, and Indo-Pakistanis, using the AmpFlSTR® Yfiler PCR Amplification Kit and the SNaPshot Multiplex Kit. Results STRs analysis found 299 different haplotypes and SNPs analysis 11 different haplogroups. Haplotypes and haplogroups were analyzed and compared between different ethnic groups. Significant differences were found among all the population groups, except between Italians and Indo-Pakistanis and between Albanians and Indo-Pakistanis. Conclusions Typing both STRs and SNPs on the Y chromosome could become useful in determining ethnic origin of a potential suspect. PMID:23771759

  10. A high resolution genetic linkage map of soybean based on 357 recombinant inbred lines genotyped with BARCSoySNP6K

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to construct a high density genetic map of soybean (Glycine max L. Merr) using a high throughput single nucleotide polymorphism (SNP) genotyping on 357 F7 recombinant inbred lines (RILs) from a cross of ‘Wyandot’ × PI 567301B. Of 5,403 SNP loci scored from the Infiniu...

  11. SNP-based genotyping in lentil: linking sequence information with phenotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lentil (Lens culinaris) has been late to enter the world of high throughput molecular analysis due to a general lack of genomic resources. Using a 454 sequencing-based approach, SNPs have been identified in genes across the lentil genome. Several hundred have been turned into single SNP KASP assay...

  12. An improved consensus linkage map of barley based on flow-sorted chromosomes and SNP markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent advances in high-throughput genotyping have made it easier to combine information from different mapping populations into consensus genetic maps, which provide increased marker density and genome coverage compared to individual maps. Previously, a SNP-based genotyping platform was developed a...

  13. A Coordinated Approach to Peach SNP Discovery in RosBREED

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the USDA-funded multi-institutional and trans-disciplinary project, “RosBREED”, crop-specific SNP genome scan platforms are being developed for peach, apple, strawberry, and cherry at a resolution of at least one polymorphic SNP marker every 5 cM in any random cross, for use in Pedigree-Based Ana...

  14. SNP discovery and allele frequency estimation by deep sequencing of reduced representation libraries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genome projects routinely produce draft sequences for species from diverse evolutionary clades, but generally do not create single nucleotide polymorphism (SNP) resources. We present an approach for de novo SNP discovery based on short-read sequencing of reduced representation libraries (RRL) to ge...

  15. Exploring the efficacy of paternity and kinship testing based on single nucleotide polymorphisms.

    PubMed

    Mo, Shao-Kang; Liu, Ya-Cheng; Wang, Sheng-qi; Bo, Xiao-Chen; Li, Zhen; Chen, Ying; Ni, Ming

    2016-05-01

    Short tandem repeats (STRs) are conventional genetic markers typically used for paternity and kinship testing. As supplementary markers of STRs, single nucleotide polymorphisms (SNPs) have less discrimination power but broader applicability to degraded samples. The rapid improvement of next-generation sequencing (NGS) and multiplex amplification technologies also make it possible now to simultaneously identify dozens or even hundreds of SNP loci in a single pool. However, few studies have been endeavored to kinship testing based on SNP loci. In this study, we genotyped 90 autosomal human identity SNP loci with NGS, and investigated their testing efficacies based on the likelihood ratio model in eight pedigree scenarios involving paternity, half/full-sibling, uncle/nephew, and first-cousin relationships. We found that these SNPs might be sufficient to discriminate paternity and full-sibling, but impractical for more distant relatives such as uncle and cousin. Furthermore, we conducted an in silico study to obtain the theoretical tendency of how testing efficacy varied with increasing number of SNP loci. For each testing battery in a given pedigree scenario, we obtained distributions of logarithmic likelihood ratio for both simulated relatives and unrelated controls. The proportion of the overlapping area between the two distributions was defined as a false testing level (FTL) to evaluate the testing efficacy. We estimated that 85, 127, 491, and 1,858 putative SNP loci were required to discriminate paternity, full-sibling, half-sibling/uncle-nephew, and first-cousin (FTL, 0.1%), respectively. To test a half-sibling or nephew, an additional uncle relative could be included to decrease the required number of putative SNP loci to ∼320 (FTL, 0.1%). As a systematic computation of paternity and kinship testing based only on SNPs, our results could be informative for further studies and applications on paternity and kinship testing using SNP loci. PMID:26952733

  16. Microarray-based estimation of SNP allele-frequency in pooled DNA using the Langmuir kinetic model

    PubMed Central

    Yin, Bin-Cheng; Li, Honghua; Ye, Bang-Ce

    2008-01-01

    Background High throughput genotyping of single nucleotide polymorphisms (SNPs) for genome-wide association requires technologies for generating millions of genotypes with relative ease but also at a reasonable cost and with high accuracy. In this work, we have developed a theoretical approach to estimate allele frequency in pooled DNA samples, based on the physical principles of DNA immobilization and hybridization on solid surface using the Langmuir kinetic model and quantitative analysis of the allelic signals. Results This method can successfully distinguish allele frequencies differing by 0.01 in the actual pool of clinical samples, and detect alleles with a frequency as low as 2%. The accuracy of measuring known allele frequencies is very high, with the strength of correlation between measured and actual frequencies having an r2 = 0.9992. These results demonstrated that this method could allow the accurate estimation of absolute allele frequencies in pooled samples of DNA in a feasible and inexpensive way. Conclusion We conclude that this novel strategy for quantitative analysis of the ratio of SNP allelic sequences in DNA pools is an inexpensive and feasible alternative for detecting polymorphic differences in candidate gene association studies and genome-wide linkage disequilibrium scans. PMID:19087310

  17. Association of single nucleotide polymorphism (SNP) markers in candidate genes and QTL regions with pork quality traits in commercial pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous reports have described genetic markers or genomic regions (QTL) associated with pork quality and/or palatability. Validation of these associations in other commercial populations is necessary before these markers should be used. Therefore, 156 SNP markers from 45 candidate genes and 8 QTL r...

  18. Association of Single Nucleotide Polymorphism (SNP) Markers in Candidate Genes and QTL Regions with Pork Quality in Commercial Pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous reports have described genetic markers or genomic regions (QTL) associated with pork quality and/or palatability. Validation of these associations in other commercial populations is necessary before these markers should be used. Therefore, we tested 130 SNP markers from 35 candidate genes a...

  19. Single nucleotide polymorphism (SNP) discovery in rainbow trout using restriction site associated DNA (RAD) sequencing of doubled haploids and assessment of polymorphism in a population survey

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Our goal is to produce a high-throughput SNP genotyping platform for genomic analyses in rainbow trout that will enable fine mapping of QTL, whole genome association studies, genomic selection for improved aquaculture production traits, and genetic analyses of wild populations that aid ...

  20. SNP genetic polymorphisms of MDR-1, CYP1A2 and CYPB11 genes in four canine breeds upon toxicological evaluation.

    PubMed

    Gagliardi, Rosa; Llambí, Silvia; Arruga, M Victoria

    2015-01-01

    The fields of pharmacogenetics and pharmacogenomics have become increasingly promising regarding the clinical application of genetic data to aid in prevention of adverse reactions. Specific screening tests can predict which animals express modified proteins or genetic sequences responsible for adverse effects associated with a drug. Among the genetic variations that have been investigated in dogs, the multidrug resistance gene (MDR) is the best studied. However, other genes such as CYP1A2 and CYP2B11 control the protein syntheses involved in the metabolism of many drugs. In the present study, the MDR-1, CYP1A2 and CYP2B11 genes were examined to identify SNP polymorphisms associated with these genes in the following four canine breeds: Uruguayan Cimarron, Border Collie, Labrador Retriever and German Shepherd. The results revealed that several SNPs of the CYP1A2 and CYP2B11 genes are potential targets for drug sensitivity investigations. PMID:25797294

  1. SNP genetic polymorphisms of MDR-1, CYP1A2 and CYPB11 genes in four canine breeds upon toxicological evaluation

    PubMed Central

    Gagliardi, Rosa; Llambí, Silvia

    2015-01-01

    The fields of pharmacogenetics and pharmacogenomics have become increasingly promising regarding the clinical application of genetic data to aid in prevention of adverse reactions. Specific screening tests can predict which animals express modified proteins or genetic sequences responsible for adverse effects associated with a drug. Among the genetic variations that have been investigated in dogs, the multidrug resistance gene (MDR) is the best studied. However, other genes such as CYP1A2 and CYP2B11 control the protein syntheses involved in the metabolism of many drugs. In the present study, the MDR-1, CYP1A2 and CYP2B11 genes were examined to identify SNP polymorphisms associated with these genes in the following four canine breeds: Uruguayan Cimarron, Border Collie, Labrador Retriever and German Shepherd. The results revealed that several SNPs of the CYP1A2 and CYP2B11 genes are potential targets for drug sensitivity investigations. PMID:25797294

  2. A Single-Array-Based Method for Detecting Copy Number Variants Using Affymetrix High Density SNP Arrays and its Application to Breast Cancer

    PubMed Central

    Li, Ming; Wen, Yalu; Fu, Wenjiang

    2014-01-01

    Cumulative evidence has shown that structural variations, due to insertions, deletions, and inversions of DNA, may contribute considerably to the development of complex human diseases, such as breast cancer. High-throughput genotyping technologies, such as Affymetrix high density single-nucleotide polymorphism (SNP) arrays, have produced large amounts of genetic data for genome-wide SNP genotype calling and copy number estimation. Meanwhile, there is a great need for accurate and efficient statistical methods to detect copy number variants. In this article, we introduce a hidden-Markov-model (HMM)-based method, referred to as the PICR-CNV, for copy number inference. The proposed method first estimates copy number abundance for each single SNP on a single array based on the raw fluorescence values, and then standardizes the estimated copy number abundance to achieve equal footing among multiple arrays. This method requires no between-array normalization, and thus, maintains data integrity and independence of samples among individual subjects. In addition to our efforts to apply new statistical technology to raw fluorescence values, the HMM has been applied to the standardized copy number abundance in order to reduce experimental noise. Through simulations, we show our refined method is able to infer copy number variants accurately. Application of the proposed method to a breast cancer dataset helps to identify genomic regions significantly associated with the disease. PMID:26279618

  3. Development of a New Molecular Subtyping Tool for Salmonella enterica Serovar Enteritidis Based on Single Nucleotide Polymorphism Genotyping Using PCR

    PubMed Central

    Kelly, Hilary; Dupras, Andrée Ann; Belanger, Sebastien; Devenish, John

    2014-01-01

    The lack of a sufficiently discriminatory molecular subtyping tool for Salmonella enterica serovar Enteritidis has hindered source attribution efforts and impeded regulatory actions required to disrupt its food-borne transmission. The underlying biological reason for the ineffectiveness of current molecular subtyping tools such as pulsed-field gel electrophoresis (PFGE) and phage typing appears to be related to the high degree of clonality of S. Enteritidis. By interrogating the organism's genome, we previously identified single nucleotide polymorphisms (SNP) distributed throughout the chromosome and have designed a highly discriminatory PCR-based SNP typing test based on 60 polymorphic loci. The application of the SNP-PCR method to DNA samples from S. Enteritidis strains (n = 55) obtained from a variety of sources has led to the differentiation and clustering of the S. Enteritidis isolates into 12 clades made up of 2 to 9 isolates per clade. Significantly, the SNP-PCR assay was able to further differentiate predominant PFGE types (e.g., XAI.0003) and phage types (e.g., phage type 8) into smaller subsets. The SNP-PCR subtyping test proved to be an accurate, precise, and quantitative tool for evaluating the relationships among the S. Enteritidis isolates tested in this study and should prove useful for clustering related S. Enteritidis isolates involved in outbreaks. PMID:25297333

  4. Development of a new molecular subtyping tool for Salmonella enterica serovar Enteritidis based on single nucleotide polymorphism genotyping using PCR.

    PubMed

    Ogunremi, Dele; Kelly, Hilary; Dupras, Andrée Ann; Belanger, Sebastien; Devenish, John

    2014-12-01

    The lack of a sufficiently discriminatory molecular subtyping tool for Salmonella enterica serovar Enteritidis has hindered source attribution efforts and impeded regulatory actions required to disrupt its food-borne transmission. The underlying biological reason for the ineffectiveness of current molecular subtyping tools such as pulsed-field gel electrophoresis (PFGE) and phage typing appears to be related to the high degree of clonality of S. Enteritidis. By interrogating the organism's genome, we previously identified single nucleotide polymorphisms (SNP) distributed throughout the chromosome and have designed a highly discriminatory PCR-based SNP typing test based on 60 polymorphic loci. The application of the SNP-PCR method to DNA samples from S. Enteritidis strains (n = 55) obtained from a variety of sources has led to the differentiation and clustering of the S. Enteritidis isolates into 12 clades made up of 2 to 9 isolates per clade. Significantly, the SNP-PCR assay was able to further differentiate predominant PFGE types (e.g., XAI.0003) and phage types (e.g., phage type 8) into smaller subsets. The SNP-PCR subtyping test proved to be an accurate, precise, and quantitative tool for evaluating the relationships among the S. Enteritidis isolates tested in this study and should prove useful for clustering related S. Enteritidis isolates involved in outbreaks. PMID:25297333

  5. Typing SNP based on the near-infrared spectroscopy and artificial neural network

    NASA Astrophysics Data System (ADS)

    Ren, Li; Wang, Wei-Peng; Gao, Yu-Zhen; Yu, Xiao-Wei; Xie, Hong-Ping

    2009-07-01

    Based on the near-infrared spectra (NIRS) of the measured samples as the discriminant variables of their genotypes, the genotype discriminant model of SNP has been established by using back-propagation artificial neural network (BP-ANN). Taking a SNP (857G > A) of N-acetyltransferase 2 (NAT2) as an example, DNA fragments containing the SNP site were amplified by the PCR method based on a pair of primers to obtain the three-genotype (GG, AA, and GA) modeling samples. The NIRS-s of the amplified samples were directly measured in transmission by using quartz cell. Based on the sample spectra measured, the two BP-ANN-s were combined to obtain the stronger ability of the three-genotype classification. One of them was established to compress the measured NIRS variables by using the resilient back-propagation algorithm, and another network established by Levenberg-Marquardt algorithm according to the compressed NIRS-s was used as the discriminant model of the three-genotype classification. For the established model, the root mean square error for the training and the prediction sample sets were 0.0135 and 0.0132, respectively. Certainly, this model could rightly predict the three genotypes (i.e. the accuracy of prediction samples was up to100%) and had a good robust for the prediction of unknown samples. Since the three genotypes of SNP could be directly determined by using the NIRS-s without any preprocessing for the analyzed samples after PCR, this method is simple, rapid and low-cost.

  6. A SNP-based consensus genetic map for synteny-based trait targeting in faba bean (Vicia faba L.).

    PubMed

    Webb, Anne; Cottage, Amanda; Wood, Thomas; Khamassi, Khalil; Hobbs, Douglas; Gostkiewicz, Krystyna; White, Mark; Khazaei, Hamid; Ali, Mohamed; Street, Daniel; Duc, Gérard; Stoddard, Fred L; Maalouf, Fouad; Ogbonnaya, Francis C; Link, Wolfgang; Thomas, Jane; O'Sullivan, Donal M

    2016-01-01

    Faba bean (Vicia faba L.) is a globally important nitrogen-fixing legume, which is widely grown in a diverse range of environments. In this work, we mine and validate a set of 845 SNPs from the aligned transcriptomes of two contrasting inbred lines. Each V. faba SNP is assigned by BLAST analysis to a single Medicago orthologue. This set of syntenically anchored polymorphisms were then validated as individual KASP assays, classified according to their informativeness and performance on a panel of 37 inbred lines, and the best performing 757 markers used to genotype six mapping populations. The six resulting linkage maps were merged into a single consensus map on which 687 SNPs were placed on six linkage groups, each presumed to correspond to one of the six V. faba chromosomes. This sequence-based consensus map was used to explore synteny with the most closely related crop species, lentil and the most closely related fully sequenced genome, Medicago. Large tracts of uninterrupted colinearity were found between faba bean and Medicago, making it relatively straightforward to predict gene content and order in mapped genetic interval. As a demonstration of this, we mapped a flower colour gene to a 2-cM interval of Vf chromosome 2 which was highly colinear with Mt3. The obvious candidate gene from 78 gene models in the collinear Medicago chromosome segment was the previously characterized MtWD40-1 gene controlling anthocyanin production in Medicago and resequencing of the Vf orthologue showed a putative causative deletion of the entire 5' end of the gene. PMID:25865502

  7. Single nucleotide polymorphism-based microarray analysis for the diagnosis of hydatidiform moles

    PubMed Central

    XIE, YINGJUN; PEI, XIAOJUAN; DONG, YU; WU, HUIQUN; WU, JIANZHU; SHI, HUIJUAN; ZHUANG, XUYING; SUN, XIAOFANG; HE, JIALING

    2016-01-01

    In clinical diagnostics, single nucleotide polymorphism (SNP)-based microarray analysis enables the detection of copy number variations (CNVs), as well as copy number neutral regions, that are absent of heterozygosity throughout the genome. The aim of the present study was to evaluate the effectiveness and sensitivity of SNP-based microarray analysis in the diagnosis of hydatidiform mole (HM). By using whole-genome SNP microarray analysis, villous genotypes were detected, and the ploidy of villous tissue was determined to identify HMs. A total of 66 villous tissues and two twin tissues were assessed in the present study. Among these samples, 11 were triploid, one was tetraploid, 23 were abnormal aneuploidy, three were complete genome homozygosity, and the remaining ones were normal ploidy. The most noteworthy finding of the present study was the identification of six partial HMs and three complete HMs from those samples that were not identified as being HMs on the basis of the initial diagnosis of experienced obstetricians. This study has demonstrated that the application of an SNP-based microarray analysis was able to increase the sensitivity of diagnosis for HMs with partial and complete HMs, which makes the identification of these diseases at an early gestational age possible. PMID:27151252

  8. Haplotype inference from unphased SNP data in heterozygous polyploids based on SAT

    PubMed Central

    Neigenfind, Jost; Gyetvai, Gabor; Basekow, Rico; Diehl, Svenja; Achenbach, Ute; Gebhardt, Christiane; Selbig, Joachim; Kersten, Birgit

    2008-01-01

    Background Haplotype inference based on unphased SNP markers is an important task in population genetics. Although there are different approaches to the inference of haplotypes in diploid species, the existing software is not suitable for inferring haplotypes from unphased SNP data in polyploid species, such as the cultivated potato (Solanum tuberosum). Potato species are tetraploid and highly heterozygous. Results Here we present the software SATlotyper which is able to handle polyploid and polyallelic data. SATlo-typer uses the Boolean satisfiability problem to formulate Haplotype Inference by Pure Parsimony. The software excludes existing haplotype inferences, thus allowing for calculation of alternative inferences. As it is not known which of the multiple haplotype inferences are best supported by the given unphased data set, we use a bootstrapping procedure that allows for scoring of alternative inferences. Finally, by means of the bootstrapping scores, it is possible to optimise the phased genotypes belonging to a given haplotype inference. The program is evaluated with simulated and experimental SNP data generated for heterozygous tetraploid populations of potato. We show that, instead of taking the first haplotype inference reported by the program, we can significantly improve the quality of the final result by applying additional methods that include scoring of the alternative haplotype inferences and genotype optimisation. For a sub-population of nineteen individuals, the predicted results computed by SATlotyper were directly compared with results obtained by experimental haplotype inference via sequencing of cloned amplicons. Prediction and experiment gave similar results regarding the inferred haplotypes and phased genotypes. Conclusion Our results suggest that Haplotype Inference by Pure Parsimony can be solved efficiently by the SAT approach, even for data sets of unphased SNP from heterozygous polyploids. SATlotyper is freeware and is distributed as

  9. A SNP Based High-Density Linkage Map of Apis cerana Reveals a High Recombination Rate Similar to Apis mellifera

    PubMed Central

    Huang, Zachary Y.; Wu, Xiao Bo; Zhu, Yong Qiang; Zheng, Hua Jun; Zeng, Zhi Jiang

    2013-01-01

    Background The Eastern honey bee, Apis cerana Fabricius, is distributed in southern and eastern Asia, from India and China to Korea and Japan and southeast to the Moluccas. This species is also widely kept for honey production besides Apis mellifera. Apis cerana is also a model organism for studying social behavior, caste determination, mating biology, sexual selection, and host-parasite interactions. Few resources are available for molecular research in this species, and a linkage map was never constructed. A linkage map is a prerequisite for quantitative trait loci mapping and for analyzing genome structure. We used the Chinese honey bee, Apis cerana cerana to construct the first linkage map in the Eastern honey bee. Results F2 workers (N = 103) were genotyped for 126,990 single nucleotide polymorphisms (SNPs). After filtering low quality and those not passing the Mendel test, we obtained 3,000 SNPs, 1,535 of these were informative and used to construct a linkage map. The preliminary map contains 19 linkage groups, we then mapped the 19 linkage groups to 16 chromosomes by comparing the markers to the genome of A. mellfiera. The final map contains 16 linkage groups with a total of 1,535 markers. The total genetic distance is 3,942.7 centimorgans (cM) with the largest linkage group (180 loci) measuring 574.5 cM. Average marker interval for all markers across the 16 linkage groups is 2.6 cM. Conclusion We constructed a high density linkage map for A. c. cerana with 1,535 markers. Because the map is based on SNP markers, it will enable easier and faster genotyping assays than randomly amplified polymorphic DNA or microsatellite based maps used in A. mellifera. PMID:24130775

  10. Use of the Illumina GoldenGate assay for single nucleotide polymorphism (SNP) genotyping in cereal crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The highly parallel genotyping assay, such as the GoldenGate assay developed by Illumina, capable of interrogating up to 3,072 single nucleotide polymorphisms (SNPs) simultaneously, has greatly facilitated the genome-wide studies particularly for crops with large and complex genome structures. In th...

  11. TcSNP: a database of genetic variation in Trypanosoma cruzi

    PubMed Central

    Ackermann, Alejandro A.; Carmona, Santiago J.; Agüero, Fernán

    2009-01-01

    The TcSNP database (http://snps.tcruzi.org) integrates information on genetic variation (polymorphisms and mutations) for different stocks, strains and isolates of Trypanosoma cruzi, the causative agent of Chagas disease. The database incorporates sequences (genes from the T. cruzi reference genome, mRNAs, ESTs and genomic sequences); multiple sequence alignments obtained from these sequences; and single-nucleotide polymorphisms and small indels identified by scanning these multiple sequence alignments. Information in TcSNP can be readily interrogated to arrive at gene sets, or SNP sets of interest based on a number of attributes. Sequence similarity searches using BLAST are also supported. This first release of TcSNP contains nearly 170 000 high-confidence candidate SNPs, derived from the analysis of annotated coding sequences. As new sequence data become available, TcSNP will incorporate these data, mapping new candidate SNPs onto the reference genome sequences. PMID:18974180

  12. Association of a genetic polymorphism (-44 C/G SNP) in the human DEFB1 gene with expression and inducibility of multiple β-defensins in gingival keratinocytes

    PubMed Central

    Kalus, Andrea A; Fredericks, L Page; Hacker, Beth M; Dommisch, Henrik; Presland, Richard B; Kimball, Janet R; Dale, Beverly A

    2009-01-01

    Background Human β-defensins (hBDs) are antimicrobial peptides with a role in innate immune defense. Our laboratory previously showed that a single nucleotide polymorphism (SNP) in the 5' untranslated region of the hBD1 gene (DEFB1), denoted -44 (rs1800972), is correlated with protection from oral Candida. Because this SNP alters the putative mRNA structure, we hypothesized that it alters hBD1 expression. Methods Transfection of reporter constructs and evaluation of antimicrobial activity and mRNA expression levels in keratinocytes from multiple donors were used to evaluate the effect of this SNP on constitutive and induced levels of expression. Results Transfection of CAT reporter constructs containing the 5' untranslated region showed that the -44 G allele yielded a 2-fold increase in CAT protein compared to other common haplotypes suggesting a cis effect on transcription or translation. The constitutive hBD1 mRNA level in human oral keratinocytes was significantly greater in cells from donors with the -44 GG genotype compared to those with the common CC genotype. Surprisingly, the hBD3 mRNA level as well as antimicrobial activity of keratinocyte extracts also correlated with the -44 G allele. Induced levels of hBD1, hBD2, and hBD3 mRNA were evaluated in keratinocytes challenged with Toll-like receptor 2 and 4 ligands, interleukin-1β, TNFα, and interferon-γ (IFNγ). In contrast to constitutive expression levels, IFNγ-induced keratinocyte hBD1 and hBD3 mRNA expression was significantly greater in cells with the common CC genotype, but there was no clear correlation of genotype with hBD2 expression. Conclusion The DEFB1 -44 G allele is associated with an increase in overall constitutive antimicrobial activity and expression of hBD1 and hBD3 in a manner that is consistent with protection from candidiasis, while the more common C allele is associated with IFNγ inducibility of these β-defensins and is likely to be more protective in conditions that enhance IFN

  13. Effect of bovine ABCG2 polymorphism Y581S SNP on secretion into milk of enterolactone, riboflavin and uric acid.

    PubMed

    Otero, J A; Miguel, V; González-Lobato, L; García-Villalba, R; Espín, J C; Prieto, J G; Merino, G; Álvarez, A I

    2016-02-01

    The ATP-binding cassette transporter G2/breast cancer resistance protein (ABCG2/BCRP) is an efflux protein involved in the bioavailability and milk secretion of endogenous and exogenous compounds, actively affecting milk composition. A limited number of physiological substrates have been identified. However, no studies have reported the specific effect of this polymorphism on the secretion into milk of compounds implicated in milk quality such as vitamins or endogenous compounds. The bovine ABCG2 Y581S polymorphism is described as a gain-of-function polymorphism that increases milk secretion and decreases plasma levels of its substrates. This work aims to study the impact of Y581S polymorphism on plasma disposition and milk secretion of compounds such as riboflavin (vitamin B2), enterolactone, a microbiota-derived metabolite from the dietary lignan secoisolariciresinol and uric acid. In vitro transport of these compounds was assessed in MDCK-II cells overexpressing the bovine ABCG2 (WT-bABCG2) and its Y581S variant (Y581S-bABCG2). Plasma and milk levels were obtained from Y/Y homozygous and Y/S heterozygous cows. The results show that riboflavin was more efficiently transported in vitro by the Y581S variant, although no differences were noted in vivo. Both uric acid and enterolactone were substrates in vitro of the bovine ABCG2 variants and were actively secreted into milk with a two-fold increase in the milk/plasma ratio for Y/S with respect to Y/Y cows. The in vitro ABCG2-mediated transport of the drug mitoxantrone, as a model substrate, was inhibited by enterolactone in both variants, suggesting the possible in vivo use of this enterolignan to reduce ABCG2-mediated milk drug transfer in cows. The Y581S variant was inhibited to a lesser extent probably due to its higher transport capacity. All these findings point to a significant role of the ABCG2 Y581S polymorphism in the milk disposition of enterolactone and the endogenous molecules riboflavin and uric acid

  14. Development of Single Nucleotide Polymorphism Markers via Sequence-based Genotyping in Cotton (Gossypium spp)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High-throughput single nucleotide polymorphism (SNP) genotyping has become the dominant approach to genomic analysis and genetic manipulation in many crop plants. In cotton (Gossypium spp), however, only a very limited number of loci and a dearth of information have been generated from SNP genotypi...

  15. SNP-VISTA

    SciTech Connect

    Shah, Nameeta; Teplitsky, Michael; Minovitsky, Simon; Dubchak, Inna

    2005-11-07

    SNP-VISTA aids in analyses of the following types of data: A. Large-scale re-sequence data of disease-related genes for discovery of associated and/or causative alleles (GeneSNP-VISTA). B. Massive amounts of ecogenomics data for studying homologous recombination in microbial populations (EcoSNP-VISTA). The main features and capabilities of SNP-VISTA are: 1) Mapping of SNPs to gene structure; 2) classification of SNPs, based on their location in the gene, frequency of occurrence in samples and allele composition; 3) clustering, based on user-defined subsets of SNPs, highlighting haplotypes as well as recombinant sequences; 4) integration of protein conservation visualization; and 5) display of automatically calculated recombination points that are user-editable. The main strength of SNP-VISTA is its graphical interface and use of visual representations, which support interactive exploration and hence better understanding of large-scale SNPs data.

  16. The Genetic Architecture of Arsenic Metabolism Efficiency:A SNP-Based Heritability Study of Bangladeshi Adults

    PubMed Central

    Gao, Jianjun; Tong, Lin; Argos, Maria; Bryan, Molly Scannell; Ahmed, Alauddin; Rakibuz-Zaman, Muhammad; Kibriya, Muhammad G.; Jasmine, Farzana; Slavkovich, Vesna; Graziano, Joseph H.

    2015-01-01

    Background Consumption of arsenic-contaminated drinking water adversely affects health. There is interindividual variation in arsenic metabolism efficiency, partially due to genetic variation in the arsenic methyltransferase (AS3MT) gene region. Objectives The goal of this study was to assess the overall contribution of genetic factors to variation in arsenic metabolism efficiency, as measured by the relative concentration of dimethylarsinic acid (DMA%) in urine. Methods Using data on genome-wide single nucleotide polymorphisms (SNPs) and urinary DMA% for 2,053 arsenic-exposed Bangladeshi individuals, we employed various SNP-based approaches for heritability estimation and polygenic modeling. Results Using data on all participants, the percent variance explained (PVE) for DMA% by all measured and imputed SNPs was 16% (p = 0.08), which was reduced to 5% (p = 0.34) after adjusting for AS3MT SNPs. Using information on close relatives only, the PVE was 63% (p = 0.0002), but decreased to 41% (p = 0.01) after adjusting for AS3MT SNPs. Regional heritability analysis confirmed 10q24.32 (AS3MT) as a major arsenic metabolism locus (PVE = 7%, p = 4.4 × 10–10), but revealed no additional regions. We observed a moderate association between a polygenic score reflecting elevated DMA% (composed of thousands of non-AS3MT SNPs) and reduced skin lesion risk in an independent sample (p < 0.05). We observed no associations for SNPs reported in prior candidate gene studies of arsenic metabolism. Conclusions Our results suggest that there are common variants outside of the AS3MT region that influence arsenic metabolism in Bangladeshi individuals, but the effects of these variants are very weak compared with variants near AS3MT. The high heritability estimates observed using family-based heritability approaches suggest substantial effects for rare variants and/or unmeasured environmental factors. Citation Gao J, Tong L, Argos M, Scannell Bryan M, Ahmed A, Rakibuz-Zaman M, Kibriya MG

  17. Integration of novel SSR and gene-based SNP marker loci in the chickpea genetic map and establishment of new anchor points with Medicago truncatula genome

    PubMed Central

    Nayak, Spurthi N.; Zhu, Hongyan; Varghese, Nicy; Datta, Subhojit; Choi, Hong-Kyu; Horres, Ralf; Jüngling, Ruth; Singh, Jagbir; Kavi Kishor, P. B.; Sivaramakrishnan, S.; Hoisington, Dave A.; Kahl, Günter; Winter, Peter; Cook, Douglas R.

    2010-01-01

    This study presents the development and mapping of simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers in chickpea. The mapping population is based on an inter-specific cross between domesticated and non-domesticated genotypes of chickpea (Cicer arietinum ICC 4958 × C. reticulatum PI 489777). This same population has been the focus of previous studies, permitting integration of new and legacy genetic markers into a single genetic map. We report a set of 311 novel SSR markers (designated ICCM—ICRISAT chickpea microsatellite), obtained from an SSR-enriched genomic library of ICC 4958. Screening of these SSR markers on a diverse panel of 48 chickpea accessions provided 147 polymorphic markers with 2–21 alleles and polymorphic information content value 0.04–0.92. Fifty-two of these markers were polymorphic between parental genotypes of the inter-specific population. We also analyzed 233 previously published (H-series) SSR markers that provided another set of 52 polymorphic markers. An additional 71 gene-based SNP markers were developed from transcript sequences that are highly conserved between chickpea and its near relative Medicago truncatula. By using these three approaches, 175 new marker loci along with 407 previously reported marker loci were integrated to yield an improved genetic map of chickpea. The integrated map contains 521 loci organized into eight linkage groups that span 2,602 cM, with an average inter-marker distance of 4.99 cM. Gene-based markers provide anchor points for comparing the genomes of Medicago and chickpea, and reveal extended synteny between these two species. The combined set of genetic markers and their integration into an improved genetic map should facilitate chickpea genetics and breeding, as well as translational studies between chickpea and Medicago. Electronic supplementary material The online version of this article (doi:10.1007/s00122-010-1265-1) contains supplementary material, which is

  18. VarySysDB: a human genetic polymorphism database based on all H-InvDB transcripts.

    PubMed

    Shimada, Makoto K; Matsumoto, Ryuzou; Hayakawa, Yosuke; Sanbonmatsu, Ryoko; Gough, Craig; Yamaguchi-Kabata, Yumi; Yamasaki, Chisato; Imanishi, Tadashi; Gojobori, Takashi

    2009-01-01

    Creation of a vast variety of proteins is accomplished by genetic variation and a variety of alternative splicing transcripts. Currently, however, the abundant available data on genetic variation and the transcriptome are stored independently and in a dispersed fashion. In order to provide a research resource regarding the effects of human genetic polymorphism on various transcripts, we developed VarySysDB, a genetic polymorphism database based on 187,156 extensively annotated matured mRNA transcripts from 36,073 loci provided by H-InvDB. VarySysDB offers information encompassing published human genetic polymorphisms for each of these transcripts separately. This allows comparisons of effects derived from a polymorphism on different transcripts. The published information we analyzed includes single nucleotide polymorphisms and deletion-insertion polymorphisms from dbSNP, copy number variations from Database of Genomic Variants, short tandem repeats and single amino acid repeats from H-InvDB and linkage disequilibrium regions from D-HaploDB. The information can be searched and retrieved by features, functions and effects of polymorphisms, as well as by keywords. VarySysDB combines two kinds of viewers, GBrowse and Sequence View, to facilitate understanding of the positional relationship among polymorphisms, genome, transcripts, loci and functional domains. We expect that VarySysDB will yield useful information on polymorphisms affecting gene expression and phenotypes. VarySysDB is available at http://h-invitational.jp/varygene/. PMID:18953038

  19. Transcriptome sequencing to produce a SNP-based genetic map of onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sequencing the onion genome is challenging because of its enormous size (16 giga base pairs DNA per haploid genome). Pilot sequencing of onion transcripts showed sufficient numbers of single nucleotide polymorphisms (SNPs) to develop a detailed genetic map. We sequenced 2.5 Roche-454 plates of norma...

  20. Single nucleotide polymorphism-based dispersal estimates using noninvasive sampling.

    PubMed

    Norman, Anita J; Spong, Göran

    2015-08-01

    Quantifying dispersal within wild populations is an important but challenging task. Here we present a method to estimate contemporary, individual-based dispersal distance from noninvasively collected samples using a specialized panel of 96 SNPs (single nucleotide polymorphisms). One main issue in conducting dispersal studies is the requirement for a high sampling resolution at a geographic scale appropriate for capturing the majority of dispersal events. In this study, fecal samples of brown bear (Ursus arctos) were collected by volunteer citizens, resulting in a high sampling resolution spanning over 45,000 km(2) in Gävleborg and Dalarna counties in Sweden. SNP genotypes were obtained for unique individuals sampled (n = 433) and subsequently used to reconstruct pedigrees. A Mantel test for isolation by distance suggests that the sampling scale was appropriate for females but not for males, which are known to disperse long distances. Euclidean distance was estimated between mother and offspring pairs identified through the reconstructed pedigrees. The mean dispersal distance was 12.9 km (SE 3.2) and 33.8 km (SE 6.8) for females and males, respectively. These results were significantly different (Wilcoxon's rank-sum test: P-value = 0.02) and are in agreement with the previously identified pattern of male-biased dispersal. Our results illustrate the potential of using a combination of noninvasively collected samples at high resolution and specialized SNPs for pedigree-based dispersal models. PMID:26357536

  1. Single nucleotide polymorphism-based dispersal estimates using noninvasive sampling

    PubMed Central

    Norman, Anita J; Spong, Göran

    2015-01-01

    Quantifying dispersal within wild populations is an important but challenging task. Here we present a method to estimate contemporary, individual-based dispersal distance from noninvasively collected samples using a specialized panel of 96 SNPs (single nucleotide polymorphisms). One main issue in conducting dispersal studies is the requirement for a high sampling resolution at a geographic scale appropriate for capturing the majority of dispersal events. In this study, fecal samples of brown bear (Ursus arctos) were collected by volunteer citizens, resulting in a high sampling resolution spanning over 45,000 km2 in Gävleborg and Dalarna counties in Sweden. SNP genotypes were obtained for unique individuals sampled (n = 433) and subsequently used to reconstruct pedigrees. A Mantel test for isolation by distance suggests that the sampling scale was appropriate for females but not for males, which are known to disperse long distances. Euclidean distance was estimated between mother and offspring pairs identified through the reconstructed pedigrees. The mean dispersal distance was 12.9 km (SE 3.2) and 33.8 km (SE 6.8) for females and males, respectively. These results were significantly different (Wilcoxon’s rank-sum test: P-value = 0.02) and are in agreement with the previously identified pattern of male-biased dispersal. Our results illustrate the potential of using a combination of noninvasively collected samples at high resolution and specialized SNPs for pedigree-based dispersal models. PMID:26357536

  2. Pyrosequencing with di-base addition for single nucleotide polymorphism genotyping.

    PubMed

    Pu, Dan; Mao, Chengguang; Cui, Lunbiao; Shi, Zhiyang; Xiao, Pengfeng

    2016-05-01

    We develop color code-based pyrosequencing with di-base addition for analysis of single nucleotide polymorphisms (SNPs). When a di-base is added into the polymerization, one or several two-color code(s) containing the type and the number of incorporated nucleotides will be produced. The code information obtained in a single run is useful to genotype SNPs as each allelic variant will give a specific pattern compared to the two other variants. Special care has to be taken while designing the di-base dispensation order. Here, we present a detailed protocol for establishing sequence-specific di-base addition to avoid nonsynchronous extension at the SNP sites. By using this technology, as few as 50 copies of DNA templates were accurately sequenced. Higher signals were produced and thus a relatively lower sample amount was required. Furthermore, the read length of per flow was increased, making simultaneous identification of multiple SNPs in a single sequencing run possible. Validation of the method was performed by using templates with two SNPs covering 37 bp and with three SNPs covering 58 bp as well as 82 bp. These SNPs were successfully genotyped by using only a sequencing primer in a single PCR/sequencing run. Our results demonstrated that this technology could be potentially developed into a powerful methodology to accurately determine SNPs so as to diagnose clinical settings. Graphical Abstract Conventional pyrosequencing adds one base (A, G, C, or T) at a time to determine the SNP site (left). Pyrosequencing with di-base addition adds di-base AG, AC, AT, CT, GC or GT at a time to determine the SNP site (right). Higher signals at SNP site will be produced due to the addition of di-bases. PMID:26935928

  3. SNP marker diversity in common bean (Phaseolus vulgaris L.).

    PubMed

    Cortés, Andrés J; Chavarro, Martha C; Blair, Matthew W

    2011-09-01

    Single nucleotide polymorphism (SNP) markers have become a genetic technology of choice because of their automation and high precision of allele calls. In this study, our goal was to develop 94 SNPs and test them across well-chosen common bean (Phaseolus vulgaris L.) germplasm. We validated and accessed SNP diversity at 84 gene-based and 10 non-genic loci using KASPar technology in a panel of 70 genotypes that have been used as parents of mapping populations and have been previously evaluated for SSRs. SNPs exhibited high levels of genetic diversity, an excess of middle frequency polymorphism, and a within-genepool mismatch distribution as expected for populations affected by sudden demographic expansions after domestication bottlenecks. This set of markers was useful for distinguishing Andean and Mesoamerican genotypes but less useful for distinguishing within each gene pool. In summary, slightly greater polymorphism and race structure was found within the Andean gene pool than within the Mesoamerican gene pool but polymorphism rate between genotypes was consistent with genepool and race identity. Our survey results represent a baseline for the choice of SNP markers for future applications because gene-associated SNPs could themselves be causative SNPs for traits. Finally, we discuss that the ideal genetic marker combination with which to carry out diversity, mapping and association studies in common bean should consider a mix of both SNP and SSR markers. PMID:21785951

  4. MultiBLUP: improved SNP-based prediction for complex traits.

    PubMed

    Speed, Doug; Balding, David J

    2014-09-01

    BLUP (best linear unbiased prediction) is widely used to predict complex traits in plant and animal breeding, and increasingly in human genetics. The BLUP mathematical model, which consists of a single random effect term, was adequate when kinships were measured from pedigrees. However, when genome-wide SNPs are used to measure kinships, the BLUP model implicitly assumes that all SNPs have the same effect-size distribution, which is a severe and unnecessary limitation. We propose MultiBLUP, which extends the BLUP model to include multiple random effects, allowing greatly improved prediction when the random effects correspond to classes of SNPs with distinct effect-size variances. The SNP classes can be specified in advance, for example, based on SNP functional annotations, and we also provide an adaptive procedure for determining a suitable partition of SNPs. We apply MultiBLUP to genome-wide association data from the Wellcome Trust Case Control Consortium (seven diseases), and from much larger studies of celiac disease and inflammatory bowel disease, finding that it consistently provides better prediction than alternative methods. Moreover, MultiBLUP is computationally very efficient; for the largest data set, which includes 12,678 individuals and 1.5 M SNPs, the total analysis can be run on a single desktop PC in less than a day and can be parallelized to run even faster. Tools to perform MultiBLUP are freely available in our software LDAK. PMID:24963154

  5. MultiBLUP: improved SNP-based prediction for complex traits

    PubMed Central

    Balding, David J.

    2014-01-01

    BLUP (best linear unbiased prediction) is widely used to predict complex traits in plant and animal breeding, and increasingly in human genetics. The BLUP mathematical model, which consists of a single random effect term, was adequate when kinships were measured from pedigrees. However, when genome-wide SNPs are used to measure kinships, the BLUP model implicitly assumes that all SNPs have the same effect-size distribution, which is a severe and unnecessary limitation. We propose MultiBLUP, which extends the BLUP model to include multiple random effects, allowing greatly improved prediction when the random effects correspond to classes of SNPs with distinct effect-size variances. The SNP classes can be specified in advance, for example, based on SNP functional annotations, and we also provide an adaptive procedure for determining a suitable partition of SNPs. We apply MultiBLUP to genome-wide association data from the Wellcome Trust Case Control Consortium (seven diseases), and from much larger studies of celiac disease and inflammatory bowel disease, finding that it consistently provides better prediction than alternative methods. Moreover, MultiBLUP is computationally very efficient; for the largest data set, which includes 12,678 individuals and 1.5 M SNPs, the total analysis can be run on a single desktop PC in less than a day and can be parallelized to run even faster. Tools to perform MultiBLUP are freely available in our software LDAK. PMID:24963154

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  7. Integrating Milk Metabolite Profile Information for the Prediction of Traditional Milk Traits Based on SNP Information for Holstein Cows

    PubMed Central

    Melzer, Nina; Wittenburg, Dörte; Repsilber, Dirk

    2013-01-01

    In this study the benefit of metabolome level analysis for the prediction of genetic value of three traditional milk traits was investigated. Our proposed approach consists of three steps: First, milk metabolite profiles are used to predict three traditional milk traits of 1,305 Holstein cows. Two regression methods, both enabling variable selection, are applied to identify important milk metabolites in this step. Second, the prediction of these important milk metabolite from single nucleotide polymorphisms (SNPs) enables the detection of SNPs with significant genetic effects. Finally, these SNPs are used to predict milk traits. The observed precision of predicted genetic values was compared to the results observed for the classical genotype-phenotype prediction using all SNPs or a reduced SNP subset (reduced classical approach). To enable a comparison between SNP subsets, a special invariable evaluation design was implemented. SNPs close to or within known quantitative trait loci (QTL) were determined. This enabled us to determine if detected important SNP subsets were enriched in these regions. The results show that our approach can lead to genetic value prediction, but requires less than 1% of the total amount of (40,317) SNPs., significantly more important SNPs in known QTL regions were detected using our approach compared to the reduced classical approach. Concluding, our approach allows a deeper insight into the associations between the different levels of the genotype-phenotype map (genotype-metabolome, metabolome-phenotype, genotype-phenotype). PMID:23990900

  8. Genome-wide single-nucleotide polymorphism array-based karyotyping in myelodysplastic syndrome and chronic myelomonocytic leukemia and its impact on treatment outcomes following decitabine treatment.

    PubMed

    Yi, Jun Ho; Huh, Jungwon; Kim, Hee-Jin; Kim, Sun-Hee; Kim, Sung Hyun; Kim, Kyoung Ha; Do, Young Rok; Mun, Yeung-Chul; Kim, Hawk; Kim, Min Kyoung; Kim, Hyeoung-Joon; Kim, TaeHyung; Kim, Dennis Dong Hwan

    2013-04-01

    Decitabine is a hypomethylating agent with proven clinical efficacy in myelodysplastic syndrome (MDS). The current study analyzed the role of single nucleotide polymorphism array (SNP-A)-based karyotyping in prediction of clinical outcome in MDS or chronic myelomonocytic leukemia (CMML) patients following decitabine therapy. A total of 61 MDS/CMML patients treated with decitabine were evaluated with Genome-Wide Human SNP 6.0 Array using DNAs derived from marrow samples. The primary endpoint was the best response rate including complete (CR) and partial response (PR) with overall (OS) and event-free survival (EFS) as secondary endpoints. Best response was noted in 14 patients (26.4 %) out of 53 evaluated patients including 12 CR and two PR with median follow-up of 21.6 months. A total of 81 abnormal SNP lesions were found in 25 out of 61 patients (41.0 %). The patients carrying abnormal SNP lesions showed an inferior CR/PR rate (p = 0.002) and showed a trend of worse OS (p = 0.02 in univariate, p = 0.09 in multivariate) compared to those without SNP lesions, but not were associated with inferior EFS. The presence of abnormal SNP lesions in MDS was associated with adverse outcomes following decitabine therapy. Further study is strongly warranted to establish the role of SNP-A karyotyping in MDS. PMID:23262795

  9. A SNP based linkage map of the turkey genome reveals multiple intrachromosomal rearrangements between the Turkey and Chicken genomes

    PubMed Central

    2010-01-01

    Background The turkey (Meleagris gallopavo) is an important agricultural species that is the second largest contributor to the world's poultry meat production. The genomic resources of turkey provide turkey breeders with tools needed for the genetic improvement of commercial breeds of turkey for economically important traits. A linkage map of turkey is essential not only for the mapping of quantitative trait loci, but also as a framework to enable the assignment of sequence contigs to specific chromosomes. Comparative genomics with chicken provides insight into mechanisms of genome evolution and helps in identifying rare genomic events such as genomic rearrangements and duplications/deletions. Results Eighteen full sib families, comprising 1008 (35 F1 and 973 F2) birds, were genotyped for 775 single nucleotide polymorphisms (SNPs). Of the 775 SNPs, 570 were informative and used to construct a linkage map in turkey. The final map contains 531 markers in 28 linkage groups. The total genetic distance covered by these linkage groups is 2,324 centimorgans (cM) with the largest linkage group (81 loci) measuring 326 cM. Average marker interval for all markers across the 28 linkage groups is 4.6 cM. Comparative mapping of turkey and chicken revealed two inter-, and 57 intrachromosomal rearrangements between these two species. Conclusion Our turkey genetic map of 531 markers reveals a genome length of 2,324 cM. Our linkage map provides an improvement of previously published maps because of the more even distribution of the markers and because the map is completely based on SNP markers enabling easier and faster genotyping assays than the microsatellitemarkers used in previous linkage maps. Turkey and chicken are shown to have a highly conserved genomic structure with a relatively low number of inter-, and intrachromosomal rearrangements. PMID:21092123

  10. METU-SNP: an integrated software system for SNP-complex disease association analysis.

    PubMed

    Ustünkar, Gürkan; Aydın Son, Yeşim

    2011-01-01

    Recently, there has been increasing research to discover genomic biomarkers, haplotypes, and potentially other variables that together contribute to the development of diseases. Single Nucleotide Polymorphisms (SNPs) are the most common form of genomic variations and they can represent an individual’s genetic variability in greatest detail. Genome-wide association studies (GWAS) of SNPs, high-dimensional case-control studies, are among the most promising approaches for identifying disease causing variants. METU-SNP software is a Java based integrated desktop application specifically designed for the prioritization of SNP biomarkers and the discovery of genes and pathways related to diseases via analysis of the GWAS case-control data. Outputs of METU-SNP can easily be utilized for the downstream biomarkers research to allow the prediction and the diagnosis of diseases and other personalized medical approaches. Here, we introduce and describe the system functionality and architecture of the METU-SNP. We believe that the METU-SNP will help researchers with the reliable identification of SNPs that are involved in the etiology of complex diseases, ultimately supporting the development of personalized medicine approaches and targeted drug discoveries. PMID:22156365

  11. A single-nucleotide polymorphism-based approach for rapid and cost-effective genetic wolf monitoring in Europe based on noninvasively collected samples.

    PubMed

    Kraus, Robert H S; vonHoldt, Bridgett; Cocchiararo, Berardino; Harms, Verena; Bayerl, Helmut; Kühn, Ralph; Förster, Daniel W; Fickel, Jörns; Roos, Christian; Nowak, Carsten

    2015-03-01

    Noninvasive genetics based on microsatellite markers has become an indispensable tool for wildlife monitoring and conservation research over the past decades. However, microsatellites have several drawbacks, such as the lack of standardisation between laboratories and high error rates. Here, we propose an alternative single-nucleotide polymorphism (SNP)-based marker system for noninvasively collected samples, which promises to solve these problems. Using nanofluidic SNP genotyping technology (Fluidigm), we genotyped 158 wolf samples (tissue, scats, hairs, urine) for 192 SNP loci selected from the Affymetrix v2 Canine SNP Array. We carefully selected an optimised final set of 96 SNPs (and discarded the worse half), based on assay performance and reliability. We found rates of missing data in this SNP set of <10% and genotyping error of ~1%, which improves genotyping accuracy by nearly an order of magnitude when compared to published data for other marker types. Our approach provides a tool for rapid and cost-effective genotyping of noninvasively collected wildlife samples. The ability to standardise genotype scoring combined with low error rates promises to constitute a major technological advancement and could establish SNPs as a standard marker for future wildlife monitoring. PMID:25042673

  12. Influence of MDM2 SNP309 and SNP285 status on the risk of cancer in the breast, prostate, lung and colon.

    PubMed

    Gansmo, Liv B; Knappskog, Stian; Romundstad, Pål; Hveem, Kristian; Vatten, Lars; Lønning, Per E

    2015-07-01

    MDM2 is a key regulator of the p53 tumor suppressor protein and is overexpressed in many human cancers. Two single nucleotide polymorphisms (SNPs) located in the MDM2 intronic promoter (P2) have been found to exert biological function. The G-allele of SNP309T>G; rs2279744 increases MDM2 transcription and has been linked to increased cancer risk. In contrast, the less frequent SNP285G>C; rs117039649, which is in complete linkage disequilibrium with SNP309 (generating a SNP285C/309G variant haplotype), has been related to reduced MDM2 transcription and to reduced risk of breast, endometrial and ovarian cancer. In this large population-based case-control study, we genotyped SNP309 and SNP285 in 10,830 individuals, including cases with cancer of the breast (n=1,717), colon (n=1,532), lung (n=1,331) and prostate (n=2,501), as well as 3,749 non-cancer controls. We found a slightly reduced risk for lung cancer among individuals harboring the SNP309TG/GG genotypes compared to the SNP309TT genotype (OR= 0.86; CI = 0.67-0.98), but this association was restricted to women (OR = 0.77; CI = 0.63-0.95) and was not present among men (OR = 0.91; CI = 0.77-1.08). Consistent with previous findings, we found a reduced risk for breast cancer among individuals carrying the SNP285GC/309GG genotype versus the SNP285GG/309GG genotype (OR = 0.55; CI = 0.33-0.93). In conclusion, our data support the hypothesis that the effects of both SNP285 and SNP309 status are tissue dependent. PMID:25431177

  13. The potential of SNP-based PCR-RFLP capillary electrophoresis analysis to authenticate and detect admixtures of Mediterranean olive oils.

    PubMed

    Bazakos, Christos; Khanfir, Emna; Aoun, Mariem; Spano, Thodhoraq; Zein, Zeina El; Chalak, Lamis; Riachy, Milad El; Abou-Sleymane, Gretta; Ali, Sihem Ben; Grati Kammoun, Naziha; Kalaitzis, Panagiotis

    2016-07-01

    Authentication and traceability of extra virgin olive oil is a challenging research task due to the complexity of fraudulent practices. In this context, the monovarietal olive oils of Protected Designation of Origin (PDO) and Protected Geographical Indication (PGI) require new tests and cutting edge analytical technologies to detect mislabeling and misleading origin. Toward this direction, DNA-based technologies could serve as a complementary to the analytical techniques assay. Single nucleotide polymorphisms are ideal molecular markers since they require short PCR analytical targets which are a prerequisite for forensic applications in olive oil sector. In the present study, a small number of polymorphic SNPs were used with an SNP-based PCR-RFLP capillary electrophoresis platform to discriminate six out of 13 monovarietal olive oils of Mediterranean origin from three different countries, Greece, Tunisia, and Lebanon. Moreover, the high sensitivity of capillary electrophoresis in combination with the DNA extraction protocol lowered the limit of detection to 10% in an admixture of Tsounati in a Koroneiki olive oil matrix. PMID:26864388

  14. SNP-guided identification of monoallelic DNA-methylation events from enrichment-based sequencing data.

    PubMed

    Steyaert, Sandra; Van Criekinge, Wim; De Paepe, Ayla; Denil, Simon; Mensaert, Klaas; Vandepitte, Katrien; Vanden Berghe, Wim; Trooskens, Geert; De Meyer, Tim

    2014-11-10

    Monoallelic gene expression is typically initiated early in the development of an organism. Dysregulation of monoallelic gene expression has already been linked to several non-Mendelian inherited genetic disorders. In humans, DNA-methylation is deemed to be an important regulator of monoallelic gene expression, but only few examples are known. One important reason is that current, cost-affordable truly genome-wide methods to assess DNA-methylation are based on sequencing post-enrichment. Here, we present a new methodology based on classical population genetic theory, i.e. the Hardy-Weinberg theorem, that combines methylomic data from MethylCap-seq with associated SNP profiles to identify monoallelically methylated loci. Applied on 334 MethylCap-seq samples of very diverse origin, this resulted in the identification of 80 genomic regions featured by monoallelic DNA-methylation. Of these 80 loci, 49 are located in genic regions of which 25 have already been linked to imprinting. Further analysis revealed statistically significant enrichment of these loci in promoter regions, further establishing the relevance and usefulness of the method. Additional validation was done using both 14 whole-genome bisulfite sequencing data sets and 16 mRNA-seq data sets. Importantly, the developed approach can be easily applied to other enrichment-based sequencing technologies, like the ChIP-seq-based identification of monoallelic histone modifications. PMID:25237057

  15. SNP-guided identification of monoallelic DNA-methylation events from enrichment-based sequencing data

    PubMed Central

    Steyaert, Sandra; Van Criekinge, Wim; De Paepe, Ayla; Denil, Simon; Mensaert, Klaas; Vandepitte, Katrien; Berghe, Wim Vanden; Trooskens, Geert; De Meyer, Tim

    2014-01-01

    Monoallelic gene expression is typically initiated early in the development of an organism. Dysregulation of monoallelic gene expression has already been linked to several non-Mendelian inherited genetic disorders. In humans, DNA-methylation is deemed to be an important regulator of monoallelic gene expression, but only few examples are known. One important reason is that current, cost-affordable truly genome-wide methods to assess DNA-methylation are based on sequencing post-enrichment. Here, we present a new methodology based on classical population genetic theory, i.e. the Hardy–Weinberg theorem, that combines methylomic data from MethylCap-seq with associated SNP profiles to identify monoallelically methylated loci. Applied on 334 MethylCap-seq samples of very diverse origin, this resulted in the identification of 80 genomic regions featured by monoallelic DNA-methylation. Of these 80 loci, 49 are located in genic regions of which 25 have already been linked to imprinting. Further analysis revealed statistically significant enrichment of these loci in promoter regions, further establishing the relevance and usefulness of the method. Additional validation was done using both 14 whole-genome bisulfite sequencing data sets and 16 mRNA-seq data sets. Importantly, the developed approach can be easily applied to other enrichment-based sequencing technologies, like the ChIP-seq-based identification of monoallelic histone modifications. PMID:25237057

  16. A robust SNP barcode for typing Mycobacterium tuberculosis complex strains

    PubMed Central

    Coll, Francesc; McNerney, Ruth; Guerra-Assunção, José Afonso; Glynn, Judith R.; Perdigão, João; Viveiros, Miguel; Portugal, Isabel; Pain, Arnab; Martin, Nigel; Clark, Taane G.

    2014-01-01

    Strain-specific genomic diversity in the Mycobacterium tuberculosis complex (MTBC) is an important factor in pathogenesis that may affect virulence, transmissibility, host response and emergence of drug resistance. Several systems have been proposed to classify MTBC strains into distinct lineages and families. Here, we investigate single-nucleotide polymorphisms (SNPs) as robust (stable) markers of genetic variation for phylogenetic analysis. We identify ~92k SNP across a global collection of 1,601 genomes. The SNP-based phylogeny is consistent with the gold-standard regions of difference (RD) classification system. Of the ~7k strain-specific SNPs identified, 62 markers are proposed to discriminate known circulating strains. This SNP-based barcode is the first to cover all main lineages, and classifies a greater number of sublineages than current alternatives. It may be used to classify clinical isolates to evaluate tools to control the disease, including therapeutics and vaccines whose effectiveness may vary by strain type. PMID:25176035

  17. Characterization and identification of cis-regulatory elements in Arabidopsis based on single-nucleotide polymorphism information.

    PubMed

    Korkuc, Paula; Schippers, Jos H M; Walther, Dirk

    2014-01-01

    Identifying regulatory elements and revealing their role in gene expression regulation remains a central goal of plant genome research. We exploited the detailed genomic sequencing information of a large number of Arabidopsis (Arabidopsis thaliana) accessions to characterize known and to identify novel cis-regulatory elements in gene promoter regions of Arabidopsis by relying on conservation as the hallmark signal of functional relevance. Based on the genomic layout and the obtained density profiles of single-nucleotide polymorphisms (SNPs) in sequence regions upstream of transcription start sites, the average length of promoter regions in Arabidopsis could be established at 500 bp. Genes associated with high degrees of variability of their respective upstream regions are preferentially involved in environmental response and signaling processes, while low levels of promoter SNP density are common among housekeeping genes. Known cis-elements were found to exhibit a decreased SNP density than sequence regions not associated with known motifs. For 15 known cis-element motifs, strong positional preferences relative to the transcription start site were detected based on their promoter SNP density profiles. Five novel candidate cis-element motifs were identified as consensus motifs of 17 sequence hexamers exhibiting increased sequence conservation combined with evidence of positional preferences, annotation information, and functional relevance for inducing correlated gene expression. Our study demonstrates that the currently available resolution of SNP data offers novel ways for the identification of functional genomic elements and the characterization of gene promoter sequences. PMID:24204023

  18. Synthesis of a fluorescence resonance energy transfer-based probe containing a tricyclic nucleoside analog for single nucleotide polymorphism typing.

    PubMed

    Hayai, Aya; Maeda, Yusuke; Ueno, Yoshihito

    2016-08-01

    Here, we report the synthesis of a fluorescence resonance energy transfer (FRET)-based probe for single nucleotide polymorphism (SNP) typing. The probe contains a fluorescent tricyclic base, 8-amino-3-(2,3-dihydroxypropyl)imidazo[4',5':5,6]pyrido[2,3-d]pyrimidine, as a donor molecule and 7-diethylaminocoumarin-3-carboxylic acid as an acceptor molecule. FRET was observed between the donor and acceptor molecules on the probe. The identity of the target bases on DNA and RNA strands could be determined using the probe. PMID:27329795

  19. A simple, bead-based assay for multiplex SNP analysis in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Single nucleotide polymorphisms (SNPs) are the most abundant form of DNA polymorphism and are highly suitable for automated analysis. These polymorphisms can be used in plants as simple genetic markers for many breeding applications and are useful for cultivar identification, genetic mapping, trait ...

  20. Population based allele frequencies of disease associated polymorphisms in the Personalized Medicine Research Project

    PubMed Central

    2010-01-01

    Background There is a lack of knowledge regarding the frequency of disease associated polymorphisms in populations and population attributable risk for many populations remains unknown. Factors that could affect the association of the allele with disease, either positively or negatively, such as race, ethnicity, and gender, may not be possible to determine without population based allele frequencies. Here we used a panel of 51 polymorphisms previously associated with at least one disease and determined the allele frequencies within the entire Personalized Medicine Research Project population based cohort. We compared these allele frequencies to those in dbSNP and other data sources stratified by race. Differences in allele frequencies between self reported race, region of origin, and sex were determined. Results There were 19544 individuals who self reported a single racial category, 19027 or (97.4%) self reported white Caucasian, and 11205 (57.3%) individuals were female. Of the 11,208 (57%) individuals with an identifiable region of origin 8337 or (74.4%) were German. 41 polymorphisms were significantly different between self reported race at the 0.05 level. Stratification of our Caucasian population by self reported region of origin revealed 19 polymorphisms that were significantly different (p = 0.05) between individuals of different origins. Further stratification of the population by gender revealed few significant differences in allele frequencies between the genders. Conclusions This represents one of the largest population based allele frequency studies to date. Stratification by self reported race and region of origin revealed wide differences in allele frequencies not only by race but also by region of origin within a single racial group. We report allele frequencies for our Asian/Hmong and American Indian populations; these two minority groups are not typically selected for population allele frequency detection. Population wide allele frequencies are

  1. Gene-based single nucleotide polymorphism discovery in bovine muscle using next-generation transcriptomic sequencing

    PubMed Central

    2013-01-01

    Background Genetic information based on molecular markers has increasingly being used in cattle breeding improvement programmes, as a mean to improve conventionally phenotypic selection. Advances in molecular genetics have led to the identification of several genetic markers associated with genes affecting economic traits. Until recently, the identification of the causative genetic variants involved in the phenotypes of interest has remained a difficult task. The advent of novel sequencing technologies now offers a new opportunity for the identification of such variants. Despite sequencing costs plummeting, sequencing whole-genomes or large targeted regions is still too expensive for most laboratories. A transcriptomic-based sequencing approach offers a cheaper alternative to identify a large number of polymorphisms and possibly to discover causative variants. In the present study, we performed a gene-based single nucleotide polymorphism (SNP) discovery analysis in bovine Longissimus thoraci, using RNA-Seq. To our knowledge, this represents the first study done in bovine muscle. Results Messenger RNAs from Longissimus thoraci from three Limousin bull calves were subjected to high-throughput sequencing. Approximately 36–46 million paired-end reads were obtained per library. A total of 19,752 transcripts were identified and 34,376 different SNPs were detected. Fifty-five percent of the SNPs were found in coding regions and ~22% resulted in an amino acid change. Applying a very stringent SNP quality threshold, we detected 8,407 different high-confidence SNPs, 18% of which are non synonymous coding SNPs. To analyse the accuracy of RNA-Seq technology for SNP detection, 48 SNPs were selected for validation by genotyping. No discrepancies were observed when using the highest SNP probability threshold. To test the usefulness of the identified SNPs, the 48 selected SNPs were assessed by genotyping 93 bovine samples, representing mostly the nine major breeds used in France

  2. SNP-SNP interactions in breast cancer susceptibility

    PubMed Central

    Onay, Venüs Ümmiye; Briollais, Laurent; Knight, Julia A; Shi, Ellen; Wang, Yuanyuan; Wells, Sean; Li, Hong; Rajendram, Isaac; Andrulis, Irene L; Ozcelik, Hilmi

    2006-01-01

    Background Breast cancer predisposition genes identified to date (e.g., BRCA1 and BRCA2) are responsible for less than 5% of all breast cancer cases. Many studies have shown that the cancer risks associated with individual commonly occurring single nucleotide polymorphisms (SNPs) are incremental. However, polygenic models suggest that multiple commonly occurring low to modestly penetrant SNPs of cancer related genes might have a greater effect on a disease when considered in combination. Methods In an attempt to identify the breast cancer risk conferred by SNP interactions, we have studied 19 SNPs from genes involved in major cancer related pathways. All SNPs were genotyped by TaqMan 5'nuclease assay. The association between the case-control status and each individual SNP, measured by the odds ratio and its corresponding 95% confidence interval, was estimated using unconditional logistic regression models. At the second stage, two-way interactions were investigated using multivariate logistic models. The robustness of the interactions, which were observed among SNPs with stronger functional evidence, was assessed using a bootstrap approach, and correction for multiple testing based on the false discovery rate (FDR) principle. Results None of these SNPs contributed to breast cancer risk individually. However, we have demonstrated evidence for gene-gene (SNP-SNP) interaction among these SNPs, which were associated with increased breast cancer risk. Our study suggests cross talk between the SNPs of the DNA repair and immune system (XPD-[Lys751Gln] and IL10-[G(-1082)A]), cell cycle and estrogen metabolism (CCND1-[Pro241Pro] and COMT-[Met108/158Val]), cell cycle and DNA repair (BARD1-[Pro24Ser] and XPD-[Lys751Gln]), and within carcinogen metabolism (GSTP1-[Ile105Val] and COMT-[Met108/158Val]) pathways. Conclusion The importance of these pathways and their communication in breast cancer predisposition has been emphasized previously, but their biological interactions

  3. Increasing the number of single nucleotide polymorphisms used in genomic evaluation of dairy cattle.

    PubMed

    Wiggans, G R; Cooper, T A; VanRaden, P M; Van Tassell, C P; Bickhart, D M; Sonstegard, T S

    2016-06-01

    GeneSeek (Neogen Corp., Lexington, KY) designed a new version of the GeneSeek Genomic Profiler HD BeadChip for Dairy Cattle, which originally had >77,000 single nucleotide polymorphisms (SNP). A set of >140,000 SNP was selected that included all SNP on the existing GeneSeek chip, all SNP used in US national genomic evaluations, SNP that were possible functional mutations, and other informative SNP. Because SNP with a lower minor allele frequency might track causative variants better, 30,000 more SNP were selected from the Illumina BovineHD Genotyping BeadChip (Illumina Inc., San Diego, CA) by choosing SNP to maximize differences in minor allele frequency between a SNP being considered for the new chip and the 2 SNP that flanked it. Single-gene tests were included if their location was known and bioinformatics indicated relevance for dairy cattle. To determine which SNP from the new chip should be included in genomic evaluations, genotypes available from chips already in use were used to impute and evaluate the SNP set. Effects for 134,511 usable SNP were estimated for all breed-trait combinations; SNP with the largest absolute values for effects were selected (5,000 for Holsteins, 1,000 for Jerseys, and 500 each for Brown Swiss and Ayrshires for each trait). To increase overlap with the 60,671 SNP currently used for genomic evaluation, 12,094 more SNP with the largest effects were added. After removing SNP with many parent-progeny conflicts, 84,937 SNP remained. Three cutoff studies were conducted with 3 SNP sets to determine reliability gain over that for parent average when evaluations based on August 2011 data were used to predict December 2014 performance. Across all traits, mean Holstein reliability gains were 32.5, 33.4, and 32.0 percentage points for 60,671, 84,937, and 134,511 SNP, respectively. After genotypes from the new chip became available, the proposed set was reduced from 84,937 to 77,321 SNP to remove SNP that were not included during manufacture

  4. SNP microarray-based 24 chromosome aneuploidy screening demonstrates that cleavage-stage FISH poorly predicts aneuploidy in embryos that develop to morphologically normal blastocysts.

    PubMed

    Northrop, L E; Treff, N R; Levy, B; Scott, R T

    2010-08-01

    Although selection of chromosomally normal embryos has the potential to improve outcomes for patients undergoing IVF, the clinical impact of aneuploidy screening by fluorescence in situ hybridization (FISH) has been controversial. There are many putative explanations including sampling error due to mosaicism, negative impact of biopsy, a lack of comprehensive chromosome screening, the possibility of embryo self-correction and poor predictive value of the technology itself. Direct analysis of the negative predictive value of FISH-based aneuploidy screening for an embryo's reproductive potential has not been performed. Although previous studies have found that cleavage-stage FISH is poorly predictive of aneuploidy in morphologically normal blastocysts, putative explanations have not been investigated. The present study used a single nucleotide polymorphism (SNP) microarray-based 24 chromosome aneuploidy screening technology to re-evaluate morphologically normal blastocysts that were diagnosed as aneuploid by FISH at the cleavage stage. Mosaicism and preferential segregation of aneuploidy to the trophectoderm (TE) were evaluated by characterization of multiple sections of the blastocyst. SNP microarray technology also provided the first opportunity to evaluate self-correction mechanisms involving extrusion or duplication of aneuploid chromosomes resulting in uniparental disomy (UPD). Of all blastocysts evaluated (n = 50), 58% were euploid in all sections despite an aneuploid FISH result. Aneuploid blastocysts displayed no evidence of preferential segregation of abnormalities to the TE. In addition, extrusion or duplication of aneuploid chromosomes resulting in UPD did not occur. These findings support the conclusion that cleavage-stage FISH technology is poorly predictive of aneuploidy in morphologically normal blastocysts. PMID:20479065

  5. SNP-VISTA

    Energy Science and Technology Software Center (ESTSC)

    2005-11-07

    SNP-VISTA aids in analyses of the following types of data: A. Large-scale re-sequence data of disease-related genes for discovery of associated and/or causative alleles (GeneSNP-VISTA). B. Massive amounts of ecogenomics data for studying homologous recombination in microbial populations (EcoSNP-VISTA). The main features and capabilities of SNP-VISTA are: 1) Mapping of SNPs to gene structure; 2) classification of SNPs, based on their location in the gene, frequency of occurrence in samples and allele composition; 3) clustering,more » based on user-defined subsets of SNPs, highlighting haplotypes as well as recombinant sequences; 4) integration of protein conservation visualization; and 5) display of automatically calculated recombination points that are user-editable. The main strength of SNP-VISTA is its graphical interface and use of visual representations, which support interactive exploration and hence better understanding of large-scale SNPs data.« less

  6. Prediction of Unobserved Single Nucleotide Polymorphism Genotypes of Jersey Cattle Using Reference Panels and Population-Based Imputation Algorithms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The availability of dense single nucleotide polymorphism (SNP) genotypes for dairy cattle has created exciting research opportunities and revolutionized practical breeding programs. Broader application of this technology will lead to situations in which genotypes from different low-, medium-, or hig...

  7. Detection of homologous horizontal gene transfer in SNP data

    Energy Science and Technology Software Center (ESTSC)

    2012-07-23

    We study the detection of mutations, sequencing errors, and homologous horizontal gene transfers (HGT) in a set of closely related microbial genomes. We base the model on single nucleotide polymorphisms (SNP's) and break the genomes into blocks to handle the rearrangement problem. Then we apply a synamic programming algorithm to model whether changes within each block are likely a result of mutations, sequencing errors, or HGT.

  8. Gene-Based Single Nucleotide Polymorphism Markers for Genetic and Association Mapping in Common Bean

    PubMed Central

    2012-01-01

    Background In common bean, expressed sequence tags (ESTs) are an underestimated source of gene-based markers such as insertion-deletions (Indels) or single-nucleotide polymorphisms (SNPs). However, due to the nature of these conserved sequences, detection of markers is difficult and portrays low levels of polymorphism. Therefore, development of intron-spanning EST-SNP markers can be a valuable resource for genetic experiments such as genetic mapping and association studies. Results In this study, a total of 313 new gene-based markers were developed at target genes. Intronic variation was deeply explored in order to capture more polymorphism. Introns were putatively identified after comparing the common bean ESTs with the soybean genome, and the primers were designed over intron-flanking regions. The intronic regions were evaluated for parental polymorphisms using the single strand conformational polymorphism (SSCP) technique and Sequenom MassARRAY system. A total of 53 new marker loci were placed on an integrated molecular map in the DOR364 × G19833 recombinant inbred line (RIL) population. The new linkage map was used to build a consensus map, merging the linkage maps of the BAT93 × JALO EEP558 and DOR364 × BAT477 populations. A total of 1,060 markers were mapped, with a total map length of 2,041 cM across 11 linkage groups. As a second application of the generated resource, a diversity panel with 93 genotypes was evaluated with 173 SNP markers using the MassARRAY-platform and KASPar technology. These results were coupled with previous SSR evaluations and drought tolerance assays carried out on the same individuals. This agglomerative dataset was examined, in order to discover marker-trait associations, using general linear model (GLM) and mixed linear model (MLM). Some significant associations with yield components were identified, and were consistent with previous findings. Conclusions In short, this study illustrates the power of intron-based

  9. SNP genotyping by DNA photoligation: application to SNP detection of genes from food crops

    NASA Astrophysics Data System (ADS)

    Yoshimura, Yoshinaga; Ohtake, Tomoko; Okada, Hajime; Ami, Takehiro; Tsukaguchi, Tadashi; Fujimoto, Kenzo

    2009-06-01

    We describe a simple and inexpensive single-nucleotide polymorphism (SNP) typing method, using DNA photoligation with 5-carboxyvinyl-2'-deoxyuridine and two fluorophores. This SNP-typing method facilitates qualitative determination of genes from indica and japonica rice, and showed a high degree of single nucleotide specificity up to 10 000. This method can be used in the SNP typing of actual genomic DNA samples from food crops.

  10. pfSNP: An integrated potentially functional SNP resource that facilitates hypotheses generation through knowledge syntheses.

    PubMed

    Wang, Jingbo; Ronaghi, Mostafa; Chong, Samuel S; Lee, Caroline G L

    2011-01-01

    Currently, >14,000,000 single nucleotide polymorphisms (SNPs) are reported. Identifying phenotype-affecting SNPs among these many SNPs pose significant challenges. Although several Web resources are available that can inform about the functionality of SNPs, these resources are mainly annotation databases and are not very comprehensive. In this article, we present a comprehensive, well-annotated, integrated pfSNP (potentially functional SNPs) Web resource (http://pfs.nus.edu.sg/), which is aimed to facilitate better hypothesis generation through knowledge syntheses mediated by better data integration and a user-friendly Web interface. pfSNP integrates >40 different algorithms/resources to interrogate >14,000,000 SNPs from the dbSNP database for SNPs of potential functional significance based on previous published reports, inferred potential functionality from genetic approaches as well as predicted potential functionality from sequence motifs. Its query interface has the user-friendly "auto-complete, prompt-as-you-type" feature and is highly customizable, facilitating different combination of queries using Boolean-logic. Additionally, to facilitate better understanding of the results and aid in hypotheses generation, gene/pathway-level information with text clouds highlighting enriched tissues/pathways as well as detailed-related information are also provided on the results page. Hence, the pfSNP resource will be of great interest to scientists focusing on association studies as well as those interested to experimentally address the functionality of SNPs. PMID:20672376

  11. Accuracy of direct genomic values in Holstein bulls and cows using subsets of SNP markers

    PubMed Central

    2010-01-01

    Background At the current price, the use of high-density single nucleotide polymorphisms (SNP) genotyping assays in genomic selection of dairy cattle is limited to applications involving elite sires and dams. The objective of this study was to evaluate the use of low-density assays to predict direct genomic value (DGV) on five milk production traits, an overall conformation trait, a survival index, and two profit index traits (APR, ASI). Methods Dense SNP genotypes were available for 42,576 SNP for 2,114 Holstein bulls and 510 cows. A subset of 1,847 bulls born between 1955 and 2004 was used as a training set to fit models with various sets of pre-selected SNP. A group of 297 bulls born between 2001 and 2004 and all cows born between 1992 and 2004 were used to evaluate the accuracy of DGV prediction. Ridge regression (RR) and partial least squares regression (PLSR) were used to derive prediction equations and to rank SNP based on the absolute value of the regression coefficients. Four alternative strategies were applied to select subset of SNP, namely: subsets of the highest ranked SNP for each individual trait, or a single subset of evenly spaced SNP, where SNP were selected based on their rank for ASI, APR or minor allele frequency within intervals of approximately equal length. Results RR and PLSR performed very similarly to predict DGV, with PLSR performing better for low-density assays and RR for higher-density SNP sets. When using all SNP, DGV predictions for production traits, which have a higher heritability, were more accurate (0.52-0.64) than for survival (0.19-0.20), which has a low heritability. The gain in accuracy using subsets that included the highest ranked SNP for each trait was marginal (5-6%) over a common set of evenly spaced SNP when at least 3,000 SNP were used. Subsets containing 3,000 SNP provided more than 90% of the accuracy that could be achieved with a high-density assay for cows, and 80% of the high-density assay for young bulls

  12. Atomic Force Microscopy for DNA SNP Identification

    NASA Astrophysics Data System (ADS)

    Valbusa, Ugo; Ierardi, Vincenzo

    The knowledge of the effects of single-nucleotide polymorphisms (SNPs) in the human genome greatly contributes to better comprehension of the relation between genetic factors and diseases. Sequence analysis of genomic DNA in different individuals reveals positions where variations that involve individual base substitutions can occur. Single-nucleotide polymorphisms are highly abundant and can have different consequences at phenotypic level. Several attempts were made to apply atomic force microscopy (AFM) to detect and map SNP sites in DNA strands. The most promising approach is the study of DNA mutations producing heteroduplex DNA strands and identifying the mismatches by means of a protein that labels the mismatches. MutS is a protein that is part of a well-known complex of mismatch repair, which initiates the process of repairing when the MutS binds to the mismatched DNA filament. The position of MutS on the DNA filament can be easily recorded by means of AFM imaging.

  13. Single nucleotide polymorphism-based microarray analysis for the diagnosis of hydatidiform moles.

    PubMed

    Xie, Yingjun; Pei, Xiaojuan; Dong, Yu; Wu, Huiqun; Wu, Jianzhu; Shi, Huijuan; Zhuang, Xuying; Sun, Xiaofang; He, Jialing

    2016-07-01

    In clinical diagnostics, single nucleotide polymorphism (SNP)-based microarray analysis enables the detection of copy number variations (CNVs), as well as copy number neutral regions, that are absent of heterozygosity throughout the genome. The aim of the present study was to evaluate the effectiveness and sensitivity of SNP‑based microarray analysis in the diagnosis of hydatidiform mole (HM). By using whole‑genome SNP microarray analysis, villous genotypes were detected, and the ploidy of villous tissue was determined to identify HMs. A total of 66 villous tissues and two twin tissues were assessed in the present study. Among these samples, 11 were triploid, one was tetraploid, 23 were abnormal aneuploidy, three were complete genome homozygosity, and the remaining ones were normal ploidy. The most noteworthy finding of the present study was the identification of six partial HMs and three complete HMs from those samples that were not identified as being HMs on the basis of the initial diagnosis of experienced obstetricians. This study has demonstrated that the application of an SNP‑based microarray analysis was able to increase the sensitivity of diagnosis for HMs with partial and complete HMs, which makes the identification of these diseases at an early gestational age possible. PMID:27151252

  14. SNP discovery in complex allotetraploid genomes (Gossypium spp., Malvaceae) using genotyping by sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dramatic decreases in the cost of DNA sequencing have enabled the development of very large numbers of markers based on single nucleotide polymorphism (SNP) for phylogenetic studies, population genetics, linkage mapping, marker-assisted breeding and other applications. Using Illumina next-generatio...

  15. Imputation of microsatellite allele from dense SNP genotypes for parentage verification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microsatellite (MS) markers have recently been used for parental verification and are still the international standard despite higher cost, error rate, and turnaround time compared with Single Nucleotide Polymorphisms (SNP)-based assays. Despite domestic and international interest from producers an...

  16. RNA-Seq-Mediated Transcriptome Analysis of a Fiberless Mutant Cotton and Its Possible Origin Based on SNP Markers

    PubMed Central

    Ma, Qifeng; Wu, Man; Pei, Wenfeng; Wang, Xiaoyan; Zhai, Honghong; Wang, Wenkui; Li, Xingli; Zhang, Jinfa; Yu, Jiwen; Yu, Shuxun

    2016-01-01

    As the longest known single-celled trichomes, cotton (Gossypium L.) fibers constitute a classic model system to investigate cell initiation and elongation. In this study, we used a high-throughput transcriptome sequencing technology to identify fiber-initiation-related single nucleotide polymorphism (SNP) markers and differentially expressed genes (DEGs) between the wild-type (WT) Upland cotton (G. hirsutum) Xuzhou 142 and its natural fuzzless-lintless mutant Xuzhou 142 fl. Approximately 700 million high-quality cDNA reads representing over 58 Gb of sequences were obtained, resulting in the identification of 28,610 SNPs—of which 17,479 were novel—from 13,960 expressed genes. Of these SNPs, 50% of SNPs in fl were identical to those of G. barbadense, which suggests the likely origin of the fl mutant from an interspecific hybridization between Xuzhou 142 and an unknown G. barbadense genotype. Of all detected SNPs, 15,555, 12,750, and 305 were classified as non-synonymous, synonymous, and pre-terminated ones, respectively. Moreover, 1,352 insertion/deletion polymorphisms (InDels) were also detected. A total of 865 DEGs were identified between the WT and fl in ovules at −3 and 0 days post-anthesis, with 302 candidate SNPs selected from these DEGs for validation by a high-resolution melting analysis and Sanger sequencing in seven cotton genotypes. The number of genotypic pairwise polymorphisms varied from 43 to 302, indicating that the identified SNPs are reliable. These SNPs should serve as good resources for breeding and genetic studies in cotton. PMID:26990639

  17. RNA-Seq-Mediated Transcriptome Analysis of a Fiberless Mutant Cotton and Its Possible Origin Based on SNP Markers.

    PubMed

    Ma, Qifeng; Wu, Man; Pei, Wenfeng; Wang, Xiaoyan; Zhai, Honghong; Wang, Wenkui; Li, Xingli; Zhang, Jinfa; Yu, Jiwen; Yu, Shuxun

    2016-01-01

    As the longest known single-celled trichomes, cotton (Gossypium L.) fibers constitute a classic model system to investigate cell initiation and elongation. In this study, we used a high-throughput transcriptome sequencing technology to identify fiber-initiation-related single nucleotide polymorphism (SNP) markers and differentially expressed genes (DEGs) between the wild-type (WT) Upland cotton (G. hirsutum) Xuzhou 142 and its natural fuzzless-lintless mutant Xuzhou 142 fl. Approximately 700 million high-quality cDNA reads representing over 58 Gb of sequences were obtained, resulting in the identification of 28,610 SNPs--of which 17,479 were novel--from 13,960 expressed genes. Of these SNPs, 50% of SNPs in fl were identical to those of G. barbadense, which suggests the likely origin of the fl mutant from an interspecific hybridization between Xuzhou 142 and an unknown G. barbadense genotype. Of all detected SNPs, 15,555, 12,750, and 305 were classified as non-synonymous, synonymous, and pre-terminated ones, respectively. Moreover, 1,352 insertion/deletion polymorphisms (InDels) were also detected. A total of 865 DEGs were identified between the WT and fl in ovules at -3 and 0 days post-anthesis, with 302 candidate SNPs selected from these DEGs for validation by a high-resolution melting analysis and Sanger sequencing in seven cotton genotypes. The number of genotypic pairwise polymorphisms varied from 43 to 302, indicating that the identified SNPs are reliable. These SNPs should serve as good resources for breeding and genetic studies in cotton. PMID:26990639

  18. Associations between polymorphisms of the gene and milk production traits in water buffaloes.

    PubMed

    Deng, T X; Pang, C Y; Lu, X R; Zhu, P; Duan, A Q; Liang, X W

    2016-03-01

    Signal transducer and activator of transcription 1 () is an important regulator of mammary gland differentiation and cell survival that has been regarded as a candidate gene affecting milk production traits in mammals. Therefore, this study was conducted to evaluate significant associations between SNP of the gene and milk production traits in buffaloes. Here, 18 SNP were identified in the buffalo gene, including 15 intronic mutations and 3 exon mutations. All the identified SNP were then genotyped using matrix-assisted laser desorption/ionization time of flight mass spectrometry methods from 192 buffaloes. All the SNP were in Hardy-Weinberg equilibrium, and 2 haplotype blocks were successfully constructed based on these SNP data, which formed 5 and 3 major haplotypes in the population (>5%), respectively. The results of association analysis showed that only SNP13 located in exon 10 was significantly associated with the milk production traits in the population ( < 0.05). Single nucleotide polymorphism 2, SNP5, SNP8, and SNP9 were associated with protein percentage, and SNP4 and SNP10 were associated with 305-d milk yield ( < 0.05). Our results provide evidence that polymorphisms of the buffalo gene are associated with milk production traits and can be used as a candidate gene for marker-assisted selection in buffalo breeding. PMID:27065255

  19. QuantiSNP: an Objective Bayes Hidden-Markov Model to detect and accurately map copy number variation using SNP genotyping data.

    PubMed

    Colella, Stefano; Yau, Christopher; Taylor, Jennifer M; Mirza, Ghazala; Butler, Helen; Clouston, Penny; Bassett, Anne S; Seller, Anneke; Holmes, Christopher C; Ragoussis, Jiannis

    2007-01-01

    Array-based technologies have been used to detect chromosomal copy number changes (aneuploidies) in the human genome. Recent studies identified numerous copy number variants (CNV) and some are common polymorphisms that may contribute to disease susceptibility. We developed, and experimentally validated, a novel computational framework (QuantiSNP) for detecting regions of copy number variation from BeadArray SNP genotyping data using an Objective Bayes Hidden-Markov Model (OB-HMM). Objective Bayes measures are used to set certain hyperparameters in the priors using a novel re-sampling framework to calibrate the model to a fixed Type I (false positive) error rate. Other parameters are set via maximum marginal likelihood to prior training data of known structure. QuantiSNP provides probabilistic quantification of state classifications and significantly improves the accuracy of segmental aneuploidy identification and mapping, relative to existing analytical tools (Beadstudio, Illumina), as demonstrated by validation of breakpoint boundaries. QuantiSNP identified both novel and validated CNVs. QuantiSNP was developed using BeadArray SNP data but it can be adapted to other platforms and we believe that the OB-HMM framework has widespread applicability in genomic research. In conclusion, QuantiSNP is a novel algorithm for high-resolution CNV/aneuploidy detection with application to clinical genetics, cancer and disease association studies. PMID:17341461

  20. DoGSD: the dog and wolf genome SNP database.

    PubMed

    Bai, Bing; Zhao, Wen-Ming; Tang, Bi-Xia; Wang, Yan-Qing; Wang, Lu; Zhang, Zhang; Yang, He-Chuan; Liu, Yan-Hu; Zhu, Jun-Wei; Irwin, David M; Wang, Guo-Dong; Zhang, Ya-Ping

    2015-01-01

    The rapid advancement of next-generation sequencing technology has generated a deluge of genomic data from domesticated dogs and their wild ancestor, grey wolves, which have simultaneously broadened our understanding of domestication and diseases that are shared by humans and dogs. To address the scarcity of single nucleotide polymorphism (SNP) data provided by authorized databases and to make SNP data more easily/friendly usable and available, we propose DoGSD (http://dogsd.big.ac.cn), the first canidae-specific database which focuses on whole genome SNP data from domesticated dogs and grey wolves. The DoGSD is a web-based, open-access resource comprising ∼ 19 million high-quality whole-genome SNPs. In addition to the dbSNP data set (build 139), DoGSD incorporates a comprehensive collection of SNPs from two newly sequenced samples (1 wolf and 1 dog) and collected SNPs from three latest dog/wolf genetic studies (7 wolves and 68 dogs), which were taken together for analysis with the population genetic statistics, Fst. In addition, DoGSD integrates some closely related information including SNP annotation, summary lists of SNPs located in genes, synonymous and non-synonymous SNPs, sampling location and breed information. All these features make DoGSD a useful resource for in-depth analysis in dog-/wolf-related studies. PMID:25404132

  1. DoGSD: the dog and wolf genome SNP database

    PubMed Central

    Bai, Bing; Zhao, Wen-Ming; Tang, Bi-Xia; Wang, Yan-Qing; Wang, Lu; Zhang, Zhang; Yang, He-Chuan; Liu, Yan-Hu; Zhu, Jun-Wei; Irwin, David M.; Wang, Guo-Dong; Zhang, Ya-Ping

    2015-01-01

    The rapid advancement of next-generation sequencing technology has generated a deluge of genomic data from domesticated dogs and their wild ancestor, grey wolves, which have simultaneously broadened our understanding of domestication and diseases that are shared by humans and dogs. To address the scarcity of single nucleotide polymorphism (SNP) data provided by authorized databases and to make SNP data more easily/friendly usable and available, we propose DoGSD (http://dogsd.big.ac.cn), the first canidae-specific database which focuses on whole genome SNP data from domesticated dogs and grey wolves. The DoGSD is a web-based, open-access resource comprising ∼19 million high-quality whole-genome SNPs. In addition to the dbSNP data set (build 139), DoGSD incorporates a comprehensive collection of SNPs from two newly sequenced samples (1 wolf and 1 dog) and collected SNPs from three latest dog/wolf genetic studies (7 wolves and 68 dogs), which were taken together for analysis with the population genetic statistics, Fst. In addition, DoGSD integrates some closely related information including SNP annotation, summary lists of SNPs located in genes, synonymous and non-synonymous SNPs, sampling location and breed information. All these features make DoGSD a useful resource for in-depth analysis in dog-/wolf-related studies. PMID:25404132

  2. A Brassica rapa Linkage Map of EST-based SNP Markers for Identification of Candidate Genes Controlling Flowering Time and Leaf Morphological Traits

    PubMed Central

    Li, Feng; Kitashiba, Hiroyasu; Inaba, Kiyofumi; Nishio, Takeshi

    2009-01-01

    For identification of genes responsible for varietal differences in flowering time and leaf morphological traits, we constructed a linkage map of Brassica rapa DNA markers including 170 EST-based markers, 12 SSR markers, and 59 BAC sequence-based markers, of which 151 are single nucleotide polymorphism (SNP) markers. By BLASTN, 223 markers were shown to have homologous regions in Arabidopsis thaliana, and these homologous loci covered nearly the whole genome of A. thaliana. Synteny analysis between B. rapa and A. thaliana revealed 33 large syntenic regions. Three quantitative trait loci (QTLs) for flowering time were detected. BrFLC1 and BrFLC2 were linked to the QTLs for bolting time, budding time, and flowering time. Three SNPs in the promoter, which may be the cause of low expression of BrFLC2 in the early-flowering parental line, were identified. For leaf lobe depth and leaf hairiness, one major QTL corresponding to a syntenic region containing GIBBERELLIN 20 OXIDASE 3 and one major QTL containing BrGL1, respectively, were detected. Analysis of nucleotide sequences and expression of these genes suggested possible involvement of these genes in leaf morphological traits. PMID:19884167

  3. Genome-wide SNP association-based localization of a dwarfism gene in Friesian dwarf horses.

    PubMed

    Orr, N; Back, W; Gu, J; Leegwater, P; Govindarajan, P; Conroy, J; Ducro, B; Van Arendonk, J A M; MacHugh, D E; Ennis, S; Hill, E W; Brama, P A J

    2010-12-01

    The recent completion of the horse genome and commercial availability of an equine SNP genotyping array has facilitated the mapping of disease genes. We report putative localization of the gene responsible for dwarfism, a trait in Friesian horses that is thought to have a recessive mode of inheritance, to a 2-MB region of chromosome 14 using just 10 affected animals and 10 controls. We successfully genotyped 34,429 SNPs that were tested for association with dwarfism using chi-square tests. The most significant SNP in our study, BIEC2-239376 (P(2df)=4.54 × 10(-5), P(rec)=7.74 × 10(-6)), is located close to a gene implicated in human dwarfism. Fine-mapping and resequencing analyses did not aid in further localization of the causative variant, and replication of our findings in independent sample sets will be necessary to confirm these results. PMID:21070269

  4. Genotyping-in-Thousands by sequencing (GT-seq): A cost effective SNP genotyping method based on custom amplicon sequencing.

    PubMed

    Campbell, Nathan R; Harmon, Stephanie A; Narum, Shawn R

    2015-07-01

    Genotyping-in-Thousands by sequencing (GT-seq) is a method that uses next-generation sequencing of multiplexed PCR products to generate genotypes from relatively small panels (50-500) of targeted single-nucleotide polymorphisms (SNPs) for thousands of individuals in a single Illumina HiSeq lane. This method uses only unlabelled oligos and PCR master mix in two thermal cycling steps for amplification of targeted SNP loci. During this process, sequencing adapters and dual barcode sequence tags are incorporated into the amplicons enabling thousands of individuals to be pooled into a single sequencing library. Post sequencing, reads from individual samples are split into individual files using their unique combination of barcode sequences. Genotyping is performed with a simple perl script which counts amplicon-specific sequences for each allele, and allele ratios are used to determine the genotypes. We demonstrate this technique by genotyping 2068 individual steelhead trout (Oncorhynchus mykiss) samples with a set of 192 SNP markers in a single library sequenced in a single Illumina HiSeq lane. Genotype data were 99.9% concordant to previously collected TaqMan(™) genotypes at the same 192 loci, but call rates were slightly lower with GT-seq (96.4%) relative to Taqman (99.0%). Of the 192 SNPs, 187 were genotyped in ≥90% of the individual samples and only 3 SNPs were genotyped in <70% of samples. This study demonstrates amplicon sequencing with GT-seq greatly reduces the cost of genotyping hundreds of targeted SNPs relative to existing methods by utilizing a simple library preparation method and massive efficiency of scale. PMID:25476721

  5. Construction of a versatile SNP array for pyramiding useful genes of rice.

    PubMed

    Kurokawa, Yusuke; Noda, Tomonori; Yamagata, Yoshiyuki; Angeles-Shim, Rosalyn; Sunohara, Hidehiko; Uehara, Kanako; Furuta, Tomoyuki; Nagai, Keisuke; Jena, Kshirod Kumar; Yasui, Hideshi; Yoshimura, Atsushi; Ashikari, Motoyuki; Doi, Kazuyuki

    2016-01-01

    DNA marker-assisted selection (MAS) has become an indispensable component of breeding. Single nucleotide polymorphisms (SNP) are the most frequent polymorphism in the rice genome. However, SNP markers are not readily employed in MAS because of limitations in genotyping platforms. Here the authors report a Golden Gate SNP array that targets specific genes controlling yield-related traits and biotic stress resistance in rice. As a first step, the SNP genotypes were surveyed in 31 parental varieties using the Affymetrix Rice 44K SNP microarray. The haplotype information for 16 target genes was then converted to the Golden Gate platform with 143-plex markers. Haplotypes for the 14 useful allele are unique and can discriminate among all other varieties. The genotyping consistency between the Affymetrix microarray and the Golden Gate array was 92.8%, and the accuracy of the Golden Gate array was confirmed in 3 F2 segregating populations. The concept of the haplotype-based selection by using the constructed SNP array was proofed. PMID:26566831

  6. Development of a cassava core collection based on single nucleotide polymorphism markers.

    PubMed

    Oliveira, E J; Ferreira, C F; Santos, V S; Oliveira, G A F

    2014-01-01

    Single nucleotide polymorphism (SNP) markers were used in the largest cassava (Manihot esculenta Crantz) germplasm collection from Brazil to develop core collections based on the maximization strategy. Subsets with 61, 64, 84, 128, 256, and 384 cassava accessions were selected and named PoHEU, MST64, PoRAN, MST128, MST256, and MST384, respectively. All the 798 alleles identified by 402 SNP markers in the entire collection were captured in all core collections. Only small alterations in the diversity parameters were observed for the different core collections compared with the complete collection. Because of the optimal adjustment of the validation parameters representative of the complete collection, the absence of genotypes with high genetic similarity and the maximization of the genetic distances between accessions of the PoHEU core collection, which contained 4.7% of the accessions of the complete collection, maximized the genetic conservation of this important cassava collection. Furthermore, the development of this core collection will allow concentrated efforts toward future characterization and agronomic evaluation of accessions to maximize the diversity and genetic gains in cassava breeding programs. PMID:25158266

  7. SNP marker detection and genotyping in tilapia.

    PubMed

    Van Bers, N E M; Crooijmans, R P M A; Groenen, M A M; Dibbits, B W; Komen, J

    2012-09-01

    We have generated a unique resource consisting of nearly 175 000 short contig sequences and 3569 SNP markers from the widely cultured GIFT (Genetically Improved Farmed Tilapia) strain of Nile tilapia (Oreochromis niloticus). In total, 384 SNPs were selected to monitor the wider applicability of the SNPs by genotyping tilapia individuals from different strains and different geographical locations. In all strains and species tested (O. niloticus, O. aureus and O. mossambicus), the genotyping assay was working for a similar number of SNPs (288-305 SNPs). The actual number of polymorphic SNPs was, as expected, highest for individuals from the GIFT population (255 SNPs). In the individuals from an Egyptian strain and in individuals caught in the wild in the basin of the river Volta, 197 and 163 SNPs were polymorphic, respectively. A pairwise calculation of Nei's genetic distance allowed the discrimination of the individual strains and species based on the genotypes determined with the SNP set. We expect that this set will be widely applicable for use in tilapia aquaculture, e.g. for pedigree reconstruction. In addition, this set is currently used for assaying the genetic diversity of native Nile tilapia in areas where tilapia is, or will be, introduced in aquaculture projects. This allows the tracing of escapees from aquaculture and the monitoring of effects of introgression and hybridization. PMID:22524158

  8. Contrasting signals of positive selection in genes involved in human skin-color variation from tests based on SNP scans and resequencing

    PubMed Central

    2011-01-01

    Background Numerous genome-wide scans conducted by genotyping previously ascertained single-nucleotide polymorphisms (SNPs) have provided candidate signatures for positive selection in various regions of the human genome, including in genes involved in pigmentation traits. However, it is unclear how well the signatures discovered by such haplotype-based test statistics can be reproduced in tests based on full resequencing data. Four genes (oculocutaneous albinism II (OCA2), tyrosinase-related protein 1 (TYRP1), dopachrome tautomerase (DCT), and KIT ligand (KITLG)) implicated in human skin-color variation, have shown evidence for positive selection in Europeans and East Asians in previous SNP-scan data. In the current study, we resequenced 4.7 to 6.7 kb of DNA from each of these genes in Africans, Europeans, East Asians, and South Asians. Results Applying all commonly used neutrality-test statistics for allele frequency distribution to the newly generated sequence data provided conflicting results regarding evidence for positive selection. Previous haplotype-based findings could not be clearly confirmed. Although some tests were marginally significant for some populations and genes, none of them were significant after multiple-testing correction. Combined P values for each gene-population pair did not improve these results. Application of Approximate Bayesian Computation Markov chain Monte Carlo based to these sequence data using a simple forward simulator revealed broad posterior distributions of the selective parameters for all four genes, providing no support for positive selection. However, when we applied this approach to published sequence data on SLC45A2, another human pigmentation candidate gene, we could readily confirm evidence for positive selection, as previously detected with sequence-based and some haplotype-based tests. Conclusions Overall, our data indicate that even genes that are strong biological candidates for positive selection and show

  9. Cloud Computing-Based TagSNP Selection Algorithm for Human Genome Data

    PubMed Central

    Hung, Che-Lun; Chen, Wen-Pei; Hua, Guan-Jie; Zheng, Huiru; Tsai, Suh-Jen Jane; Lin, Yaw-Ling

    2015-01-01

    Single nucleotide polymorphisms (SNPs) play a fundamental role in human genetic variation and are used in medical diagnostics, phylogeny construction, and drug design. They provide the highest-resolution genetic fingerprint for identifying disease associations and human features. Haplotypes are regions of linked genetic variants that are closely spaced on the genome and tend to be inherited together. Genetics research has revealed SNPs within certain haplotype blocks that introduce few distinct common haplotypes into most of the population. Haplotype block structures are used in association-based methods to map disease genes. In this paper, we propose an efficient algorithm for identifying haplotype blocks in the genome. In chromosomal haplotype data retrieved from the HapMap project website, the proposed algorithm identified longer haplotype blocks than an existing algorithm. To enhance its performance, we extended the proposed algorithm into a parallel algorithm that copies data in parallel via the Hadoop MapReduce framework. The proposed MapReduce-paralleled combinatorial algorithm performed well on real-world data obtained from the HapMap dataset; the improvement in computational efficiency was proportional to the number of processors used. PMID:25569088

  10. Cloud computing-based TagSNP selection algorithm for human genome data.

    PubMed

    Hung, Che-Lun; Chen, Wen-Pei; Hua, Guan-Jie; Zheng, Huiru; Tsai, Suh-Jen Jane; Lin, Yaw-Ling

    2015-01-01

    Single nucleotide polymorphisms (SNPs) play a fundamental role in human genetic variation and are used in medical diagnostics, phylogeny construction, and drug design. They provide the highest-resolution genetic fingerprint for identifying disease associations and human features. Haplotypes are regions of linked genetic variants that are closely spaced on the genome and tend to be inherited together. Genetics research has revealed SNPs within certain haplotype blocks that introduce few distinct common haplotypes into most of the population. Haplotype block structures are used in association-based methods to map disease genes. In this paper, we propose an efficient algorithm for identifying haplotype blocks in the genome. In chromosomal haplotype data retrieved from the HapMap project website, the proposed algorithm identified longer haplotype blocks than an existing algorithm. To enhance its performance, we extended the proposed algorithm into a parallel algorithm that copies data in parallel via the Hadoop MapReduce framework. The proposed MapReduce-paralleled combinatorial algorithm performed well on real-world data obtained from the HapMap dataset; the improvement in computational efficiency was proportional to the number of processors used. PMID:25569088

  11. High-throughput SNP discovery in the rabbit (Oryctolagus cuniculus) genome by next-generation semiconductor-based sequencing.

    PubMed

    Bertolini, F; Schiavo, G; Scotti, E; Ribani, A; Martelli, P L; Casadio, R; Fontanesi, L

    2014-04-01

    The European rabbit (Oryctolagus cuniculus) is a domesticated species with one of the broadest ranges of economic and scientific applications and fields of investigation. Rabbit genome information and assembly are available (oryCun2.0), but so far few studies have investigated its variability, and massive discovery of polymorphisms has not been published yet for this species. Here, we sequenced two reduced representation libraries (RRLs) to identify single nucleotide polymorphisms (SNPs) in the rabbit genome. Genomic DNA of 10 rabbits belonging to different breeds was pooled and digested with two restriction enzymes (HaeIII and RsaI) to create two RRLs which were sequenced using the Ion Torrent Personal Genome Machine. The two RRLs produced 2 917 879 and 4 046 871 reads, for a total of 280.51 Mb (248.49 Mb with quality >20) and 417.28 Mb (360.89 Mb with quality >20) respectively of sequenced DNA. About 90% and 91% respectively of the obtained reads were mapped on the rabbit genome, covering a total of 15.82% of the oryCun2.0 genome version. The mapping and ad hoc filtering procedures allowed to reliably call 62 491 SNPs. SNPs in a few genomic regions were validated by Sanger sequencing. The Variant Effect Predictor Web tool was used to map SNPs on the current version of the rabbit genome. The obtained results will be useful for many applied and basic research programs for this species and will contribute to the development of cost-effective solutions for high-throughput SNP genotyping in the rabbit. PMID:24444082

  12. Investigation of single nucleotide polymorphism loci susceptible to degradation by ultraviolet light.

    PubMed

    Machida, Mitsuyo; Taki, Takashi; Shimada, Ryo; Kibayashi, Kazuhiko

    2016-10-01

    DNA in biological fluids is often degraded by environmental factors. Given that single nucleotide polymorphism (SNP) analyses require shorter amplicons than short tandem repeat (STR) analyses do, their use in human identification using degraded samples has recently attracted attention. Although various SNP loci are used to analyze degraded samples, it is unclear which ones are more appropriate. To characterize and identify SNP loci that are susceptible or resistant to degradation, we artificially degraded DNA, obtained from buccal swabs from 11 volunteers, by exposure to ultraviolet (UV) light for different durations (254 nm for 5, 15, 30, 60, or 120 min) and analyzed the resulting SNP loci. DNA degradation was assessed using gel electrophoresis, STR, and SNP profiling. DNA fragmentation occurred within 5 min of UV irradiation, and successful STR and SNP profiling decreased with increasing duration. However, 73% of SNP loci were still detected correctly in DNA samples irradiated for 120 min, a dose that rendered STR loci undetectable. The unsuccessful SNP typing and the base call failure of nucleotides neighboring the SNPs were traced to rs1031825, and we found that this SNP was susceptible to UV light. When comparing the detection efficiencies of STR and SNP loci, SNP typing was more successful than STR typing, making it effective when using degraded DNA. However, it is important to use rs1031825 with caution when interpreting SNP analyses of degraded DNA. PMID:27570235

  13. Large Scale Association Analysis for Drug Addiction: Results from SNP to Gene

    PubMed Central

    Guo, Xiaobo; Liu, Zhifa; Wang, Xueqin; Zhang, Heping

    2012-01-01

    Many genetic association studies used single nucleotide polymorphisms (SNPs) data to identify genetic variants for complex diseases. Although SNP-based associations are most common in genome-wide association studies (GWAS), gene-based association analysis has received increasing attention in understanding genetic etiologies for complex diseases. While both methods have been used to analyze the same data, few genome-wide association studies compare the results or observe the connection between them. We performed a comprehensive analysis of the data from the Study of Addiction: Genetics and Environment (SAGE) and compared the results from the SNP-based and gene-based analyses. Our results suggest that the gene-based method complements the individual SNP-based analysis, and conceptually they are closely related. In terms of gene findings, our results validate many genes that were either reported from the analysis of the same dataset or based on animal studies for substance dependence. PMID:23365539

  14. Allele diversity for abiotic stress responsive candidate genes in chickpea reference set using gene based SNP markers

    PubMed Central

    Roorkiwal, Manish; Nayak, Spurthi N.; Thudi, Mahendar; Upadhyaya, Hari D.; Brunel, Dominique; Mournet, Pierre; This, Dominique; Sharma, Prakash C.; Varshney, Rajeev K.

    2014-01-01

    Chickpea is an important food legume crop for the semi-arid regions, however, its productivity is adversely affected by various biotic and abiotic stresses. Identification of candidate genes associated with abiotic stress response will help breeding efforts aiming to enhance its productivity. With this objective, 10 abiotic stress responsive candidate genes were selected on the basis of prior knowledge of this complex trait. These 10 genes were subjected to allele specific sequencing across a chickpea reference set comprising 300 genotypes including 211 genotypes of chickpea mini core collection. A total of 1.3 Mbp sequence data were generated. Multiple sequence alignment (MSA) revealed 79 SNPs and 41 indels in nine genes while the CAP2 gene was found to be conserved across all the genotypes. Among 10 candidate genes, the maximum number of SNPs (34) was observed in abscisic acid stress and ripening (ASR) gene including 22 transitions, 11 transversions and one tri-allelic SNP. Nucleotide diversity varied from 0.0004 to 0.0029 while polymorphism information content (PIC) values ranged from 0.01 (AKIN gene) to 0.43 (CAP2 promoter). Haplotype analysis revealed that alleles were represented by more than two haplotype blocks, except alleles of the CAP2 and sucrose synthase (SuSy) gene, where only one haplotype was identified. These genes can be used for association analysis and if validated, may be useful for enhancing abiotic stress, including drought tolerance, through molecular breeding. PMID:24926299

  15. The SNP Consortium website: past, present and future.

    PubMed

    Thorisson, Gudmundur A; Stein, Lincoln D

    2003-01-01

    The SNP Consortium website (http://snp.cshl.org) has undergone many changes since its initial conception three years ago. The database back end has been changed from the venerable ACeDB to the more scalable MySQL engine. Users can access the data via gene or single nucleotide polymorphism (SNP) keyword searches and browse or dump SNP data to textfiles. A graphical genome browsing interface shows SNPs mapped onto the genome assembly in the context of externally available gene predictions and other features. SNP allele frequency and genotype data are available via FTP-download and on individual SNP report web pages. SNP linkage maps are available for download and for browsing in a comparative map viewer. All software components of the data coordinating center (DCC) website (http://snp.cshl.org) are open source. PMID:12519964

  16. Silicon Based System for Single-Nucleotide-Polymorphism Detection: Chip Fabrication and Thermal Characterization of Polymerase Chain Reaction Microchamber

    NASA Astrophysics Data System (ADS)

    Majeed, Bivragh; Jones, Ben; Tezcan, Deniz S.; Tutunjyan, Nina; Haspeslagh, Luc; Peeters, Sara; Fiorini, Paolo; de Beeck, Maaike Op; Van Hoof, Chris; Hiraoka, Maki; Tanaka, Hiroyuki; Yamashita, Ichiro

    2012-04-01

    A single nucleotide polymorphism (SNP) is a difference in the DNA sequence of one nucleotide only. We recently proposed a lab-on-a-chip (LoC) system which has the potentiality of fast, sensitive and highly specific SNP detection. Most of the chip components are silicon based and fabricated within a single process. In this paper, the newly developed fabrication method for the silicon chip is presented. The robust and reliable process allows etching structures on the same chip with very different aspect ratios. The characterization of a crucial component to the LoC SNP detector, the microreactor where DNA amplification is performed, is also detailed. Thanks to innovative design and fabrication methodologies, the microreactor has an excellent thermal isolation from the surrounding silicon substrate. This allows for highly localized temperature control. Furthermore, the microreactor is demonstrated to have rapid heating and cooling rates, allowing for rapid amplification of the target DNA fragments. Successful DNA amplification in the microreactor is demonstrated.

  17. Genome-wide prediction of cancer driver genes based on SNP and cancer SNV data.

    PubMed

    He, Quanze; He, Quanyuan; Liu, Xiaohui; Wei, Youheng; Shen, Suqin; Hu, Xiaohui; Li, Qiao; Peng, Xiangwen; Wang, Lin; Yu, Long

    2014-01-01

    Identifying cancer driver genes and exploring their functions are essential and the most urgent need in basic cancer research. Developing efficient methods to differentiate between driver and passenger somatic mutations revealed from large-scale cancer genome sequencing data is critical to cancer driver gene discovery. Here, we compared distinct features of SNP with SNV data in detail and found that the weighted ratio of SNV to SNP (termed as WVPR) is an excellent indicator for cancer driver genes. The power of WVPR was validated by accurate predictions of known drivers. We ranked most of human genes by WVPR and did functional analyses on the list. The results demonstrate that driver genes are usually highly enriched in chromatin organization related genes/pathways. And some protein complexes, such as histone acetyltransferase, histone methyltransferase, telomerase, centrosome, sin3 and U12-type spliceosomal complexes, are hot spots of driver mutations. Furthermore, this study identified many new potential driver genes (e.g. NTRK3 and ZIC4) and pathways including oxidative phosphorylation pathway, which were not deemed by previous methods. Taken together, our study not only developed a method to identify cancer driver genes/pathways but also provided new insights into molecular mechanisms of cancer development. PMID:25057442

  18. Developing diagnostic SNP panels for the identification of true fruit flies (Diptera: Tephritidae) within the limits of COI-based species delimitation

    PubMed Central

    2013-01-01

    Background Rapid and reliable identification of quarantine pests is essential for plant inspection services to prevent introduction of invasive species. For insects, this may be a serious problem when dealing with morphologically similar cryptic species complexes and early developmental stages that lack distinctive characters useful for taxonomic identification. DNA based barcoding could solve many of these problems. The standard barcode fragment, an approx. 650 base pairs long sequence of the 5′end of the mitochondrial cytochrome oxidase I (COI), enables differentiation of a very wide range of arthropods. However, problems remain in some taxa, such as Tephritidae, where recent genetic differentiation among some of the described species hinders accurate molecular discrimination. Results In order to explore the full species discrimination potential of COI, we sequenced the barcoding region of the COI gene of a range of economically important Tephritid species and complemented these data with all GenBank and BOLD entries for the systematic group available as of January 2012. We explored the limits of species delimitation of this barcode fragment among 193 putative Tephritid species and established operational taxonomic units (OTUs), between which discrimination is reliably possible. Furthermore, to enable future development of rapid diagnostic assays based on this sequence information, we characterized all single nucleotide polymorphisms (SNPs) and established “near-minimal” sets of SNPs that differentiate among all included OTUs with at least three and four SNPs, respectively. Conclusions We found that although several species cannot be differentiated based on the genetic diversity observed in COI and hence form composite OTUs, 85% of all OTUs correspond to described species. Because our SNP panels are developed based on all currently available sequence information and rely on a minimal pairwise difference of three SNPs, they are highly reliable and hence

  19. Detecting Susceptibility to Breast Cancer with SNP-SNP Interaction Using BPSOHS and Emotional Neural Networks.

    PubMed

    Wang, Xiao; Peng, Qinke; Fan, Yue

    2016-01-01

    Studies for the association between diseases and informative single nucleotide polymorphisms (SNPs) have received great attention. However, most of them just use the whole set of useful SNPs and fail to consider the SNP-SNP interactions, while these interactions have already been proven in biology experiments. In this paper, we use a binary particle swarm optimization with hierarchical structure (BPSOHS) algorithm to improve the effective of PSO for the identification of the SNP-SNP interactions. Furthermore, in order to use these SNP interactions in the susceptibility analysis, we propose an emotional neural network (ENN) to treat SNP interactions as emotional tendency. Different from the normal architecture, just as the emotional brain, this architecture provides a specific path to treat the emotional value, by which the SNP interactions can be considered more quickly and directly. The ENN helps us use the prior knowledge about the SNP interactions and other influence factors together. Finally, the experimental results prove that the proposed BPSOHS_ENN algorithm can detect the informative SNP-SNP interaction and predict the breast cancer risk with a much higher accuracy than existing methods. PMID:27294121

  20. Detecting Susceptibility to Breast Cancer with SNP-SNP Interaction Using BPSOHS and Emotional Neural Networks

    PubMed Central

    Wang, Xiao; Fan, Yue

    2016-01-01

    Studies for the association between diseases and informative single nucleotide polymorphisms (SNPs) have received great attention. However, most of them just use the whole set of useful SNPs and fail to consider the SNP-SNP interactions, while these interactions have already been proven in biology experiments. In this paper, we use a binary particle swarm optimization with hierarchical structure (BPSOHS) algorithm to improve the effective of PSO for the identification of the SNP-SNP interactions. Furthermore, in order to use these SNP interactions in the susceptibility analysis, we propose an emotional neural network (ENN) to treat SNP interactions as emotional tendency. Different from the normal architecture, just as the emotional brain, this architecture provides a specific path to treat the emotional value, by which the SNP interactions can be considered more quickly and directly. The ENN helps us use the prior knowledge about the SNP interactions and other influence factors together. Finally, the experimental results prove that the proposed BPSOHS_ENN algorithm can detect the informative SNP-SNP interaction and predict the breast cancer risk with a much higher accuracy than existing methods. PMID:27294121

  1. Identification and Evaluation of Single-Nucleotide Polymorphisms in Allotetraploid Peanut (Arachis hypogaea L.) Based on Amplicon Sequencing Combined with High Resolution Melting (HRM) Analysis

    PubMed Central

    Hong, Yanbin; Pandey, Manish K.; Liu, Ying; Chen, Xiaoping; Liu, Hong; Varshney, Rajeev K.; Liang, Xuanqiang; Huang, Shangzhi

    2015-01-01

    The cultivated peanut (Arachis hypogaea L.) is an allotetraploid (AABB) species derived from the A-genome (Arachis duranensis) and B-genome (Arachis ipaensis) progenitors. Presence of two versions of a DNA sequence based on the two progenitor genomes poses a serious technical and analytical problem during single nucleotide polymorphism (SNP) marker identification and analysis. In this context, we have analyzed 200 amplicons derived from expressed sequence tags (ESTs) and genome survey sequences (GSS) to identify SNPs in a panel of genotypes consisting of 12 cultivated peanut varieties and two diploid progenitors representing the ancestral genomes. A total of 18 EST-SNPs and 44 genomic-SNPs were identified in 12 peanut varieties by aligning the sequence of A. hypogaea with diploid progenitors. The average frequency of sequence polymorphism was higher for genomic-SNPs than the EST-SNPs with one genomic-SNP every 1011 bp as compared to one EST-SNP every 2557 bp. In order to estimate the potential and further applicability of these identified SNPs, 96 peanut varieties were genotyped using high resolution melting (HRM) method. Polymorphism information content (PIC) values for EST-SNPs ranged between 0.021 and 0.413 with a mean of 0.172 in the set of peanut varieties, while genomic-SNPs ranged between 0.080 and 0.478 with a mean of 0.249. Total 33 SNPs were used for polymorphism detection among the parents and 10 selected lines from mapping population Y13Zh (Zhenzhuhei × Yueyou13). Of the total 33 SNPs, nine SNPs showed polymorphism in the mapping population Y13Zh, and seven SNPs were successfully mapped into five linkage groups. Our results showed that SNPs can be identified in allotetraploid peanut with high accuracy through amplicon sequencing and HRM assay. The identified SNPs were very informative and can be used for different genetic and breeding applications in peanut. PMID:26697032

  2. Identification and Evaluation of Single-Nucleotide Polymorphisms in Allotetraploid Peanut (Arachis hypogaea L.) Based on Amplicon Sequencing Combined with High Resolution Melting (HRM) Analysis.

    PubMed

    Hong, Yanbin; Pandey, Manish K; Liu, Ying; Chen, Xiaoping; Liu, Hong; Varshney, Rajeev K; Liang, Xuanqiang; Huang, Shangzhi

    2015-01-01

    The cultivated peanut (Arachis hypogaea L.) is an allotetraploid (AABB) species derived from the A-genome (Arachis duranensis) and B-genome (Arachis ipaensis) progenitors. Presence of two versions of a DNA sequence based on the two progenitor genomes poses a serious technical and analytical problem during single nucleotide polymorphism (SNP) marker identification and analysis. In this context, we have analyzed 200 amplicons derived from expressed sequence tags (ESTs) and genome survey sequences (GSS) to identify SNPs in a panel of genotypes consisting of 12 cultivated peanut varieties and two diploid progenitors representing the ancestral genomes. A total of 18 EST-SNPs and 44 genomic-SNPs were identified in 12 peanut varieties by aligning the sequence of A. hypogaea with diploid progenitors. The average frequency of sequence polymorphism was higher for genomic-SNPs than the EST-SNPs with one genomic-SNP every 1011 bp as compared to one EST-SNP every 2557 bp. In order to estimate the potential and further applicability of these identified SNPs, 96 peanut varieties were genotyped using high resolution melting (HRM) method. Polymorphism information content (PIC) values for EST-SNPs ranged between 0.021 and 0.413 with a mean of 0.172 in the set of peanut varieties, while genomic-SNPs ranged between 0.080 and 0.478 with a mean of 0.249. Total 33 SNPs were used for polymorphism detection among the parents and 10 selected lines from mapping population Y13Zh (Zhenzhuhei × Yueyou13). Of the total 33 SNPs, nine SNPs showed polymorphism in the mapping population Y13Zh, and seven SNPs were successfully mapped into five linkage groups. Our results showed that SNPs can be identified in allotetraploid peanut with high accuracy through amplicon sequencing and HRM assay. The identified SNPs were very informative and can be used for different genetic and breeding applications in peanut. PMID:26697032

  3. Transcriptome sequencing to produce SNP-based genetic maps of onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We used the 454 platform to sequence from normalized cDNA libraries from each of two inbred lines of onion (OH1 and 5225). From approximately 1.6 million reads from each inbred, 27,065 and 33,254 cDNA contigs were assembled from OH1 and 5225, respectively. In total, 3,364 single nucleotide polymorph...

  4. Multiplex Detection and SNP Genotyping in a Single Fluorescence Channel

    PubMed Central

    Fu, Guoliang; Miles, Andrea; Alphey, Luke

    2012-01-01

    Probe-based PCR is widely used for SNP (single nucleotide polymorphism) genotyping and pathogen nucleic acid detection due to its simplicity, sensitivity and cost-effectiveness. However, the multiplex capability of hydrolysis probe-based PCR is normally limited to one target (pathogen or allele) per fluorescence channel. Current fluorescence PCR machines typically have 4–6 channels. We present a strategy permitting the multiplex detection of multiple targets in a single detection channel. The technique is named Multiplex Probe Amplification (MPA). Polymorphisms of the CYP2C9 gene (cytochrome P450, family 2, subfamily C, polypeptide 9, CYP2C9*2) and human papillomavirus sequences HPV16, 18, 31, 52 and 59 were chosen as model targets for testing MPA. The allele status of the CYP2C9*2 determined by MPA was entirely concordant with the reference TaqMan® SNP Genotyping Assays. The four HPV strain sequences could be independently detected in a single fluorescence detection channel. The results validate the multiplex capacity, the simplicity and accuracy of MPA for SNP genotyping and multiplex detection using different probes labeled with the same fluorophore. The technique offers a new way to multiplex in a single detection channel of a closed-tube PCR. PMID:22272339

  5. Multiplex detection and SNP genotyping in a single fluorescence channel.

    PubMed

    Fu, Guoliang; Miles, Andrea; Alphey, Luke

    2012-01-01

    Probe-based PCR is widely used for SNP (single nucleotide polymorphism) genotyping and pathogen nucleic acid detection due to its simplicity, sensitivity and cost-effectiveness. However, the multiplex capability of hydrolysis probe-based PCR is normally limited to one target (pathogen or allele) per fluorescence channel. Current fluorescence PCR machines typically have 4-6 channels. We present a strategy permitting the multiplex detection of multiple targets in a single detection channel. The technique is named Multiplex Probe Amplification (MPA). Polymorphisms of the CYP2C9 gene (cytochrome P450, family 2, subfamily C, polypeptide 9, CYP2C9*2) and human papillomavirus sequences HPV16, 18, 31, 52 and 59 were chosen as model targets for testing MPA. The allele status of the CYP2C9*2 determined by MPA was entirely concordant with the reference TaqMan® SNP Genotyping Assays. The four HPV strain sequences could be independently detected in a single fluorescence detection channel. The results validate the multiplex capacity, the simplicity and accuracy of MPA for SNP genotyping and multiplex detection using different probes labeled with the same fluorophore. The technique offers a new way to multiplex in a single detection channel of a closed-tube PCR. PMID:22272339

  6. Susceptibility to large-joint osteoarthritis (hip and knee) is associated with BAG6 rs3117582 SNP and the VNTR polymorphism in the second exon of the FAM46A gene on chromosome 6.

    PubMed

    Etokebe, Godfrey E; Jotanovic, Zdravko; Mihelic, Radovan; Mulac-Jericevic, Biserka; Nikolic, Tamara; Balen, Sanja; Sestan, Branko; Dembic, Zlatko

    2015-01-01

    Family with sequence similarity 46, member A (FAM46A) gene VNTR and BCL2-Associated Athanogene 6 (BAG6) gene rs3117582 polymorphisms were genotyped in a case-control study with 474 large-joint (hip and knee) osteoarthritis (OA) patients and 568 controls in Croatian population by candidate-gene approach for association with OA. We found that BAG6 rs3117582 SNP genotypes were associated with protection (major allele homozygote) and susceptibility (major-minor allele heterozygote) to OA. BAG6 rs3117582 major allele (A) was associated with reduced risk to OA while the minor allele (C) was associated with increased risk to OA. We identified 6 alleles harboring 2 to 7 repeats making 20 genotypes for FAM46A. A rare FAM46A VNTR genotype comprising VNTR alleles with four and seven repeats (c/f) was associated with increased OA risk in both genders. The genotype with four and six repeats (c/e) was also associated with increased risk to OA in males. A polymorphic FAM46A allele with six repeats (e) was associated with reduced risk to OA in females. Our results suggest association between the FAM46A gene, BAG6 gene and OA in Croatian population, respectively. This is the first study to show associations between these genetic loci and OA. PMID:25231575

  7. Highly effective SNP-based association mapping and management of recessive defects in livestock.

    PubMed

    Charlier, Carole; Coppieters, Wouter; Rollin, Frédéric; Desmecht, Daniel; Agerholm, Jorgen S; Cambisano, Nadine; Carta, Eloisa; Dardano, Sabrina; Dive, Marc; Fasquelle, Corinne; Frennet, Jean-Claude; Hanset, Roger; Hubin, Xavier; Jorgensen, Claus; Karim, Latifa; Kent, Matthew; Harvey, Kirsten; Pearce, Brian R; Simon, Patricia; Tama, Nico; Nie, Haisheng; Vandeputte, Sébastien; Lien, Sigbjorn; Longeri, Maria; Fredholm, Merete; Harvey, Robert J; Georges, Michel

    2008-04-01

    The widespread use of elite sires by means of artificial insemination in livestock breeding leads to the frequent emergence of recessive genetic defects, which cause significant economic and animal welfare concerns. Here we show that the availability of genome-wide, high-density SNP panels, combined with the typical structure of livestock populations, markedly accelerates the positional identification of genes and mutations that cause inherited defects. We report the fine-scale mapping of five recessive disorders in cattle and the molecular basis for three of these: congenital muscular dystony (CMD) types 1 and 2 in Belgian Blue cattle and ichthyosis fetalis in Italian Chianina cattle. Identification of these causative mutations has an immediate translation into breeding practice, allowing marker assisted selection against the defects through avoidance of at-risk matings. PMID:18344998

  8. SSCP-SNP in pearl millet--a new marker system for comparative genetics.

    PubMed

    Bertin, I; Zhu, J H; Gale, M D

    2005-05-01

    A considerable array of genomic resources are in place in pearl millet, and marker-aided selection is already in use in the public breeding programme at ICRISAT. This paper describes experiments to extend these publicly available resources to a single nucleotide polymorphism (SNP)-based marker system. A new marker system, single-strand conformational polymorphism (SSCP)-SNP, was developed using annotated rice genomic sequences to initially predict the intron-exon borders in millet expressed sequence tags (ESTs) and then to design primers that would amplify across the introns. An adequate supply of millet ESTs was available for us to identify 299 homologues of single-copy rice genes in which the intron positions could be precisely predicted. PCR primers were then designed to amplify approximately 500-bp genomic fragments containing introns. Analysis of these fragments on SSCP gels revealed considerable polymorphism. A detailed DNA sequence analysis of variation at four of the SSCP-SNP loci over a panel of eight inbred genotypes showed complex patterns of variation, with about one SNP or indel (insertion-deletion) every 59 bp in the introns, but considerably fewer in the exons. About two-thirds of the variation was derived from SNPs and one-third from indels. Most haplotypes were detected by SSCP. As a marker system, SSCP-SNP has lower development costs than simple sequence repeats (SSRs), because much of the work is in silico, and similar deployment costs and through-put potential. The rates of polymorphism were lower but useable, with a mean PIC of 0.49 relative to 0.72 for SSRs in our eight inbred genotype panel screen. The major advantage of the system is in comparative applications. Syntenic information can be used to target SSCP-SNP markers to specific chromosomal regions or, conversely, SSCP-SNP markers can be used to unravel detailed syntenic relationships in specific parts of the genome. Finally, a preliminary analysis showed that the millet SSCP-SNP primers

  9. Genetic Diversity and Relatedness of Sweet Cherry (Prunus Avium L.) Cultivars Based on Single Nucleotide Polymorphic Markers

    PubMed Central

    Fernandez i Marti, Angel; Athanson, Blessing; Koepke, Tyson; Font i Forcada, Carolina; Dhingra, Amit; Oraguzie, Nnadozie

    2012-01-01

    Most previous studies on genetic fingerprinting and cultivar relatedness in sweet cherry were based on isoenzyme, RAPD, and simple sequence repeat (SSR) markers. This study was carried out to assess the utility of single nucleotide polymorphism (SNP) markers generated from 3′ untranslated regions (UTR) for genetic fingerprinting in sweet cherry. A total of 114 sweet cherry germplasm representing advanced selections, commercial cultivars, and old cultivars imported from different parts of the world were screened with seven SSR markers developed from other Prunus species and with 40 SNPs obtained from 3′ UTR sequences of Rainier and Bing sweet cherry cultivars. Both types of marker study had 99 accessions in common. The SSR data was used to validate the SNP results. Results showed that the average number of alleles per locus, mean observed heterozygosity, expected heterozygosity, and polymorphic information content values were higher in SSRs than in SNPs although both set of markers were similar in their grouping of the sweet cherry accessions as shown in the dendrogram. SNPs were able to distinguish sport mutants from their wild type germplasm. For example, “Stella” was separated from “Compact Stella.” This demonstrates the greater power of SNPs for discriminating mutants from their original parents than SSRs. In addition, SNP markers confirmed parentage and also determined relationships of the accessions in a manner consistent with their pedigree relationships. We would recommend the use of 3′ UTR SNPs for genetic fingerprinting, parentage verification, gene mapping, and study of genetic diversity in sweet cherry. PMID:22737155

  10. Large-Scale SNP Discovery through RNA Sequencing and SNP Genotyping by Targeted Enrichment Sequencing in Cassava (Manihot esculenta Crantz)

    PubMed Central

    Pootakham, Wirulda; Shearman, Jeremy R.; Ruang-areerate, Panthita; Sonthirod, Chutima; Sangsrakru, Duangjai; Jomchai, Nukoon; Yoocha, Thippawan; Triwitayakorn, Kanokporn; Tragoonrung, Somvong; Tangphatsornruang, Sithichoke

    2014-01-01

    Cassava (Manihot esculenta Crantz) is one of the most important crop species being the main source of dietary energy in several countries. Marker-assisted selection has become an essential tool in plant breeding. Single nucleotide polymorphism (SNP) discovery via transcriptome sequencing is an attractive strategy for genome complexity reduction in organisms with large genomes. We sequenced the transcriptome of 16 cassava accessions using the Illumina HiSeq platform and identified 675,559 EST-derived SNP markers. A subset of those markers was subsequently genotyped by capture-based targeted enrichment sequencing in 100 F1 progeny segregating for starch viscosity phenotypes. A total of 2,110 non-redundant SNP markers were used to construct a genetic map. This map encompasses 1,785 cM and consists of 19 linkage groups. A major quantitative trait locus (QTL) controlling starch pasting properties was identified and shown to coincide with the QTL previously reported for this trait. With a high-density SNP-based linkage map presented here, we also uncovered a novel QTL associated with starch pasting time on LG 10. PMID:25551642

  11. Neuroantibodies (NAB) in African-American Children with Heavy Metal Exposures are Associated with Cytokine and Human Leukocyte Antigen (HLA) Polymorphisms (SNP)

    EPA Science Inventory

    Polymorphisms in cytokine and HLA genes are associated with allergies, autoimmunity and neurodegeneration (ND). Samples from 131 African-American children (71 males; 60 females) in the Mechanistic Indicators of Childhood Asthma (MICA) study were used to determine SNPs of IL-4, IL...

  12. Association of Neuroantibodies(NAB) with Glutathione-S-Tranferase(GST) Isozyme Polymorphisms(SNP) in African-American Children with Heavy Metal Exposure

    EPA Science Inventory

    Polymorphisms in GST isozymes have implications in heavy metal accumulation, neurodegeneration, and immune-mediated disease. Blood cell DNA and sera from 131 African-American children were used to determine GST Pi [rs947895 (C>A), rs17593068 (G>T), rs6591256 (A>G), rs187...

  13. Imputation of microsatellite alleles from dense SNP genotypes for parentage verification across multiple Bos taurus and Bos indicus breeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microsatellite markers (MS) have traditionally been used for parental verification and are still the international standard in spite of their higher cost, error rate, and turnaround time compared with Single Nucleotide Polymorphisms (SNP) -based assays. Despite domestic and international demands fr...

  14. Smarter clustering methods for SNP genotype calling

    PubMed Central

    Lin, Yan; Tseng, George C.; Cheong, Soo Yeon; Bean, Lora J. H.; Sherman, Stephanie L.; Feingold, Eleanor

    2008-01-01

    Motivation: Most genotyping technologies for single nucleotide polymorphism (SNP) markers use standard clustering methods to ‘call’ the SNP genotypes. These methods are not always optimal in distinguishing the genotype clusters of a SNP because they do not take advantage of specific features of the genotype calling problem. In particular, when family data are available, pedigree information is ignored. Furthermore, prior information about the distribution of the measurements for each cluster can be used to choose an appropriate model-based clustering method and can significantly improve the genotype calls. One special genotyping problem that has never been discussed in the literature is that of genotyping of trisomic individuals, such as individuals with Down syndrome. Calling trisomic genotypes is a more complicated problem, and the addition of external information becomes very important. Results: In this article, we discuss the impact of incorporating external information into clustering algorithms to call the genotypes for both disomic and trisomic data. We also propose two new methods to call genotypes using family data. One is a modification of the K-means method and uses the pedigree information by updating all members of a family together. The other is a likelihood-based method that combines the Gaussian or beta-mixture model with pedigree information. We compare the performance of these two methods and some other existing methods using simulation studies. We also compare the performance of these methods on a real dataset generated by the Illumina platform (www.illumina.com). Availability: The R code for the family-based genotype calling methods (SNPCaller) is available to be downloaded from the following website: http://watson.hgen.pitt.edu/register. Contact: liny@upmc.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:18826959

  15. Vitamin D receptor polymorphisms and survival in patients with cutaneous melanoma: a population-based study.

    PubMed

    Orlow, Irene; Reiner, Anne S; Thomas, Nancy E; Roy, Pampa; Kanetsky, Peter A; Luo, Li; Paine, Susan; Armstrong, Bruce K; Kricker, Anne; Marrett, Loraine D; Rosso, Stefano; Zanetti, Roberto; Gruber, Stephen B; Anton-Culver, Hoda; Gallagher, Richard P; Dwyer, Terence; Busam, Klaus; Begg, Colin B; Berwick, Marianne

    2016-01-01

    Factors known to affect melanoma survival include age at presentation, sex and tumor characteristics. Polymorphisms also appear to modulate survival following diagnosis. Result from other studies suggest that vitamin D receptor (VDR) polymorphisms (SNPs) impact survival in patients with glioma, renal cell carcinoma, lung, breast, prostate and other cancers; however, a comprehensive study of VDR polymorphisms and melanoma-specific survival is lacking. We aimed to investigate whether VDR genetic variation influences survival in patients with cutaneous melanoma. The analysis involved 3566 incident single and multiple primary melanoma cases enrolled in the international population-based Genes, Environment, and Melanoma Study. Melanoma-specific survival outcomes were calculated for each of 38 VDR SNPs using a competing risk analysis after adjustment for covariates. There were 254 (7.1%) deaths due to melanoma during the median 7.6 years follow-up period. VDR SNPs rs7299460, rs3782905, rs2239182, rs12370156, rs2238140, rs7305032, rs1544410 (BsmI) and rs731236 (TaqI) each had a statistically significant (trend P values < 0.05) association with melanoma-specific survival in multivariate analysis. One functional SNP (rs2239182) remained significant after adjustment for multiple testing using the Monte Carlo method. None of the SNPs associated with survival were significantly associated with Breslow thickness, ulceration or mitosis. These results suggest that the VDR gene may influence survival from melanoma, although the mechanism by which VDR exerts its effect does not seem driven by tumor aggressiveness. Further investigations are needed to confirm our results and to understand the relationship between VDR and survival in the combined context of tumor and host characteristics. PMID:26521212

  16. Accelerating genetic improvement with SNP chips and DNA sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of high-density single nucleotide polymorphism (SNP) assays is expected to have a profound impact on genetic progress in the U.S. dairy industry. In the 16 months since its initial availability, the Illumina BovineSNP50 BeadChip has been used to genotype nearly 20,000 Holsteins. Thes...

  17. Polymorphism among EST-based markers in tomato

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cultivated tomato (Lycopersicon esculentum Mill.) has a narrow genetic base. This is in part due to population genetic processes such as founder events, genetic bottlenecks, and natural and artificial selection during domestication. We characterize the nucleotide polymorphism in 26 EST-based markers...

  18. Family-Based Multi-SNP X Chromosome Analysis Using Parent Information.

    PubMed

    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

  19. Family-Based Multi-SNP X Chromosome Analysis Using Parent Information

    PubMed Central

    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

  20. A SNP genetic linkage map based on the ‘Hamilton’ by ‘Spencer’ recombinant inbred line (RIL) population identified QTL for seed Isoflavone contents in soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean is one of the most important crops worldwide for its protein, oil as well as the health beneficial phytoestrogens or isoflavone. This study reports a relatively dense SNP-Based genetic map based on ‘Hamilton’ by ‘Spencer’ recombinant inbred line (RIL) population and quantitative t...

  1. Selection and validation of potato candidate genes for maturity corrected resistance to Phytophthora infestans based on differential expression combined with SNP association and linkage mapping

    PubMed Central

    Muktar, Meki S.; Lübeck, Jens; Strahwald, Josef; Gebhardt, Christiane

    2015-01-01

    Late blight of potato (Solanum tuberosum L.) caused by the oomycete Phytophthora infestans (Mont.) de Bary, is one of the most important bottlenecks of potato production worldwide. Cultivars with high levels of durable, race unspecific, quantitative resistance are part of a solution to this problem. However, breeding for quantitative resistance is hampered by the correlation between resistance and late plant maturity, which is an undesirable agricultural attribute. The objectives of our research are (i) the identification of genes that condition quantitative resistance to P. infestans not compromised by late plant maturity and (ii) the discovery of diagnostic single nucleotide polymorphism (SNP) markers to be used as molecular tools to increase efficiency and precision of resistance breeding. Twenty two novel candidate genes were selected based on comparative transcript profiling by SuperSAGE (serial analysis of gene expression) in groups of plants with contrasting levels of maturity corrected resistance (MCR). Reproducibility of differential expression was tested by quantitative real time PCR and allele specific pyrosequencing in four new sets of genotype pools with contrasting late blight resistance levels, at three infection time points and in three independent infection experiments. Reproducibility of expression patterns ranged from 28 to 97%. Association mapping in a panel of 184 tetraploid cultivars identified SNPs in five candidate genes that were associated with MCR. These SNPs can be used in marker-assisted resistance breeding. Linkage mapping in two half-sib families (n = 111) identified SNPs in three candidate genes that were linked with MCR. The differentially expressed genes that showed association and/or linkage with MCR putatively function in phytosterol synthesis, fatty acid synthesis, asparagine synthesis, chlorophyll synthesis, cell wall modification, and in the response to pathogen elicitors. PMID:26442110

  2. COMT and MAO-A Polymorphisms and Obsessive-Compulsive Disorder: A Family-Based Association Study

    PubMed Central

    Sampaio, Aline Santos; Hounie, Ana Gabriela; Petribú, Kátia; Cappi, Carolina; Morais, Ivanil; Vallada, Homero; do Rosário, Maria Conceição; Stewart, S. Evelyn; Fargeness, Jesen; Mathews, Carol; Arnold, Paul; Hanna, Gregory L.; Richter, Margaret; Kennedy, James; Fontenelle, Leonardo; de Bragança Pereira, Carlos Alberto; Pauls, David L.; Miguel, Eurípedes Constantino

    2015-01-01

    Objective Obsessive-compulsive disorder (OCD) is a common and debilitating psychiatric illness. Although a genetic component contributes to its etiology, no single gene or mechanism has been identified to the OCD susceptibility. The catechol-O-methyltransferase (COMT) and monoamine oxidase A (MAO-A) genes have been investigated in previous OCD studies, but the results are still unclear. More recently, Taylor (2013) in a comprehensive meta-analysis of genetic association studies has identified COMT and MAO-A polymorphisms involved with OCD. In an effort to clarify the role of these two genes in OCD vulnerability, a family-based association investigation was performed as an alternative strategy to the classical case-control design. Methods Transmission disequilibrium analyses were performed after genotyping 13 single-nucleotide polymorphisms (eight in COMT and five in MAO-A) in 783 OCD trios (probands and their parents). Four different OCD phenotypes (from narrow to broad OCD definitions) and a SNP x SNP epistasis were also analyzed. Results OCD, broad and narrow phenotypes,were not associated with any of the investigated COMT and MAO-A polymorphisms. In addition, the analyses of gene-gene interaction did not show significant epistatic influences on phenotype between COMT and MAO-A. Conclusions The findings do not support an association between DSM-IV OCD and the variants of COMT or MAO-A. However, results from this study cannot exclude the contribution of these genes in the manifestation of OCD. The evaluation of broader spectrum phenotypes could help to understand the role of these and other genes in the pathophysiology of OCD and its spectrum disorders. PMID:25793616

  3. Efficient SNP Discovery by Combining Microarray and Lab-on-a-Chip Data for Animal Breeding and Selection

    PubMed Central

    Huang, Chao-Wei; Lin, Yu-Tsung; Ding, Shih-Torng; Lo, Ling-Ling; Wang, Pei-Hwa; Lin, En-Chung; Liu, Fang-Wei; Lu, Yen-Wen

    2015-01-01

    The genetic markers associated with economic traits have been widely explored for animal breeding. Among these markers, single-nucleotide polymorphism (SNPs) are gradually becoming a prevalent and effective evaluation tool. Since SNPs only focus on the genetic sequences of interest, it thereby reduces the evaluation time and cost. Compared to traditional approaches, SNP genotyping techniques incorporate informative genetic background, improve the breeding prediction accuracy and acquiesce breeding quality on the farm. This article therefore reviews the typical procedures of animal breeding using SNPs and the current status of related techniques. The associated SNP information and genotyping techniques, including microarray and Lab-on-a-Chip based platforms, along with their potential are highlighted. Examples in pig and poultry with different SNP loci linked to high economic trait values are given. The recommendations for utilizing SNP genotyping in nimal breeding are summarized. PMID:27600241

  4. Annotation-based genome-wide SNP discovery in the large and complex Aegilops tauschii genome using next-generation sequencing without a reference genome sequence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An annotation-based, genome-wide SNP discovery pipeline is reported using NGS data for large and complex genomes without a reference genome sequence. Roche 454 shotgun reads with low genome coverage of one genotype are annotated in order to distinguish single-copy sequences and repeat junctions fr...

  5. BAC-end sequence-based SNP mining in Allotetraploid Cotton (Gossypium) utilizing re-sequencing data, phylogenetic inferences and perspectives for genetic mapping

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A bacterial artificial chromosome (BAC) library and BAC-end sequences for Gossypium hirsutum L. have recently been developed. Here we report on genomic-based genome-wide SNP mining utilizing re-sequencing data with a BAC-end sequence reference for twelve G. hirsutum L. lines, one G. barbadense L. li...

  6. High-throughput SNP genotyping for breeding applications in rice using the BeadXpress platform

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multiplexed single nucleotide polymorphism (SNP) markers have the potential to increase the speed and cost-effectiveness of genotyping, provided that an optimal SNP density is used for each application. To test the efficiency of multiplexed SNP genotyping for diversity, mapping and breeding applicat...

  7. The development and characterization of a 57K SNP array for rainbow trout

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper we describe the development and characterization of the first high density single nucleotide polymorphism (SNP) genotyping array for rainbow trout. The SNP array is publically available from a commercial vendor. The SNP genotyping quality was high and validation rate was close to 90%...

  8. Polymorphism of the DNA Base Excision Repair Genes in Keratoconus

    PubMed Central

    Wojcik, Katarzyna A.; Synowiec, Ewelina; Sobierajczyk, Katarzyna; Izdebska, Justyna; Blasiak, Janusz; Szaflik, Jerzy; Szaflik, Jacek P.

    2014-01-01

    Keratoconus (KC) is a degenerative corneal disorder for which the exact pathogenesis is not yet known. Oxidative stress is reported to be associated with this disease. The stress may damage corneal biomolecules, including DNA, and such damage is primarily removed by base excision repair (BER). Variation in genes encoding BER components may influence the effectiveness of corneal cells to cope with oxidative stress. In the present work we genotyped 5 polymorphisms of 4 BER genes in 284 patients and 353 controls. The A/A genotype of the c.–1370T>A polymorphism of the DNA polymerase γ (POLG) gene was associated with increased occurrence of KC, while the A/T genotype was associated with decreased occurrence of KC. The A/G genotype and the A allele of the c.1196A>G polymorphism of the X-ray repair cross-complementing group 1 (XRCC1) were associated with increased, and the G/G genotype and the G allele, with decreased KC occurrence. Also, the C/T and T as well as C/C genotypes and alleles of the c.580C>T polymorphism of the same gene displayed relationship with KC occurrence. Neither the g.46438521G>C polymorphism of the Nei endonuclease VIII-like 1 (NEIL1) nor the c.2285T>C polymorphism of the poly(ADP-ribose) polymerase-1 (PARP-1) was associated with KC. In conclusion, the variability of the XRCC1 and POLG genes may play a role in KC pathogenesis and determine the risk of this disease. PMID:25356504

  9. Model-based verification of hypotheses on the origin of modern Japanese revisited by Bayesian inference based on genome-wide SNP data.

    PubMed

    Nakagome, Shigeki; Sato, Takehiro; Ishida, Hajime; Hanihara, Tsunehiko; Yamaguchi, Tetsutaro; Kimura, Ryosuke; Mano, Shuhei; Oota, Hiroki

    2015-06-01

    Various hypotheses for the peopling of the Japanese archipelago have been proposed, which can be classified into three models: transformation, replacement, and hybridization. In recent years, one of the hybridization models ("dual-structure model") has been widely accepted. According to this model, Neolithic hunter-gatherers known as Jomon, who are assumed to have originated in southeast Asia and lived in the Japanese archipelago greater than 10,000 years ago, admixed with an agricultural people known as Yayoi, whom were migrants from the East Asian continent 2,000-3,000 years ago. Meanwhile, some anthropologists propose that rather, morphological differences between the Jomon and Yayoi people can be explained by microevolution following the lifestyle change. To resolve this controversy, we compared three demographic models by approximate Bayesian computation using genome-wide single nucleotide polymorphism (gwSNP) data from the Ainu people who are thought to be direct descendants of indigenous Jomon. If we assume Chinese people sampled in Beijing from HapMap have the same ancestry as Yayoi, then the hybridization model is predicted to be between 29 and 63 times more likely than the replacement and transformation models, respectively. Furthermore, our data provide strong support for a model in which the Jomon lineages had population structure diversified in local areas before the admixture event. Initial divergence between the Jomon and Yayoi ancestries was dated to late Pleistocene, followed by the divergence of Jomon lineages at early Holocene. These results suggest gwSNP data provides a detailed picture of the complex hybridization model for Japanese population history. PMID:25758010

  10. Habitat-based polymorphism is common in stream fishes.

    PubMed

    Senay, Caroline; Boisclair, Daniel; Peres-Neto, Pedro R

    2015-01-01

    Morphological differences (size and shape) across habitats are common in lake fish where differences relate to two dominant contrasting habitats: the pelagic and littoral habitat. Repeated occurrence of littoral and pelagic morphs across multiple populations of several lake fish species has been considered as important evidence that polymorphism is adaptive in these systems. It has been suggested that these habitat-based polymorphic differences are due to the temporal stability of the differences between littoral and pelagic habitats. Although streams are spatially heterogeneous, they are also more temporally dynamic than lakes and it is still an open question whether streams provide the environmental conditions that promote habitat-based polymorphism. We tested whether fish from riffle, run and pool habitats, respectively, differed consistently in their morphology. Our test compared patterns of morphological variation (size and shape) in 10 fish species from the three stream habitat types in 36 separate streams distributed across three watersheds. For most species, body size and shape (after controlling for body size) differed across riffle, run and pool habitats. Unlike many lake species, the nature of these differences was not consistent across species, possibly because these species use these habitat types in different ways. Our results suggest that habitat-based polymorphism is an important feature also in stream fishes despite the fact that streams are temporally variable in contrast to lake systems. Future research is required to assess whether the patterns of habitat-based polymorphism encountered in streams have a genetic basis or they are simply the result of within generation phenotypic plasticity. PMID:25041645

  11. Highly specific SNP detection using 2D graphene electronics and DNA strand displacement

    PubMed Central

    Hwang, Michael T.; Landon, Preston B.; Lee, Joon; Choi, Duyoung; Mo, Alexander H.; Glinsky, Gennadi; Lal, Ratnesh

    2016-01-01

    Single-nucleotide polymorphisms (SNPs) in a gene sequence are markers for a variety of human diseases. Detection of SNPs with high specificity and sensitivity is essential for effective practical implementation of personalized medicine. Current DNA sequencing, including SNP detection, primarily uses enzyme-based methods or fluorophore-labeled assays that are time-consuming, need laboratory-scale settings, and are expensive. Previously reported electrical charge-based SNP detectors have insufficient specificity and accuracy, limiting their effectiveness. Here, we demonstrate the use of a DNA strand displacement-based probe on a graphene field effect transistor (FET) for high-specificity, single-nucleotide mismatch detection. The single mismatch was detected by measuring strand displacement-induced resistance (and hence current) change and Dirac point shift in a graphene FET. SNP detection in large double-helix DNA strands (e.g., 47 nt) minimize false-positive results. Our electrical sensor-based SNP detection technology, without labeling and without apparent cross-hybridization artifacts, would allow fast, sensitive, and portable SNP detection with single-nucleotide resolution. The technology will have a wide range of applications in digital and implantable biosensors and high-throughput DNA genotyping, with transformative implications for personalized medicine. PMID:27298347

  12. Highly specific SNP detection using 2D graphene electronics and DNA strand displacement.

    PubMed

    Hwang, Michael T; Landon, Preston B; Lee, Joon; Choi, Duyoung; Mo, Alexander H; Glinsky, Gennadi; Lal, Ratnesh

    2016-06-28

    Single-nucleotide polymorphisms (SNPs) in a gene sequence are markers for a variety of human diseases. Detection of SNPs with high specificity and sensitivity is essential for effective practical implementation of personalized medicine. Current DNA sequencing, including SNP detection, primarily uses enzyme-based methods or fluorophore-labeled assays that are time-consuming, need laboratory-scale settings, and are expensive. Previously reported electrical charge-based SNP detectors have insufficient specificity and accuracy, limiting their effectiveness. Here, we demonstrate the use of a DNA strand displacement-based probe on a graphene field effect transistor (FET) for high-specificity, single-nucleotide mismatch detection. The single mismatch was detected by measuring strand displacement-induced resistance (and hence current) change and Dirac point shift in a graphene FET. SNP detection in large double-helix DNA strands (e.g., 47 nt) minimize false-positive results. Our electrical sensor-based SNP detection technology, without labeling and without apparent cross-hybridization artifacts, would allow fast, sensitive, and portable SNP detection with single-nucleotide resolution. The technology will have a wide range of applications in digital and implantable biosensors and high-throughput DNA genotyping, with transformative implications for personalized medicine. PMID:27298347

  13. SNP analysis of follistatin gene associated with polycystic ovarian syndrome

    PubMed Central

    Panneerselvam, Palanisamy; Sivakumari, Kanakarajan; Jayaprakash, Ponmani; Srikanth, Ramanathan

    2010-01-01

    Follistatin has been reported as a candidate gene for polycystic ovarian syndrome (PCOS) based on linkage and association studies. In this study, investigation of polymorphisms in the FST gene was done to determine if genetic variation is associated with susceptibility to PCOS. The nucleotide sequence of human follistatin and the protein sequence of human follistatin were retrieved from the NCBI database using Entrez. The follistatin protein of human was retrieved from the Swiss-Prot database. There are 344 amino acids and the molecular weight is 38,007 Da. The ProtParam analysis shows that the isoelectric point is 5.53 and the aliphatic index is 61.25. The hydropathicity is −0.490. The domains in FST protein are as follows: Pfam-B 5005 domain from 1 to 92; EGF-like subdomain from 93 to 116; Kazal 1 domain, occurred in three places, namely, 118–164, 192–239, and 270–316. There are 31 single-nucleotide polymorphisms (SNPs) for this gene. Some are nonsynonymous, some occur in the intron region, and some in an untranslated region. Two nonsynonymous SNPs, namely, rs11745088 and rs1127760, were taken for analysis. In the SNP rs11745088, the change is E152Q. Likewise, in rs1127760, the change is C239S. SIFT (Sorting Intolerant from Tolerant) showed positions of amino acids and the single letter code of amino acids that can be tolerated or deleterious for each position. There were six SNP results and each result had links to it. The dbSNP id, primary database id, and the type of mutation whether silent and if occurring in coding region are given as phenotype alterations. The FASTA format of protein was given to the nsSNP Analyzer tool, and the variation E152Q and C239S were given as inputs in the SNP data field. E152Q change was neutral and C239S causes disease. Using PANTHER for evolutionary analysis of coding SNPs, the protein sequence was given as input and analyzed for the E152Q and C239S SNPs for deleterious effect on protein function. The genetic association

  14. SNP analysis of follistatin gene associated with polycystic ovarian syndrome.

    PubMed

    Panneerselvam, Palanisamy; Sivakumari, Kanakarajan; Jayaprakash, Ponmani; Srikanth, Ramanathan

    2010-01-01

    Follistatin has been reported as a candidate gene for polycystic ovarian syndrome (PCOS) based on linkage and association studies. In this study, investigation of polymorphisms in the FST gene was done to determine if genetic variation is associated with susceptibility to PCOS. The nucleotide sequence of human follistatin and the protein sequence of human follistatin were retrieved from the NCBI database using Entrez. The follistatin protein of human was retrieved from the Swiss-Prot database. There are 344 amino acids and the molecular weight is 38,007 Da. The ProtParam analysis shows that the isoelectric point is 5.53 and the aliphatic index is 61.25. The hydropathicity is -0.490. The domains in FST protein are as follows: Pfam-B 5005 domain from 1 to 92; EGF-like subdomain from 93 to 116; Kazal 1 domain, occurred in three places, namely, 118-164, 192-239, and 270-316. There are 31 single-nucleotide polymorphisms (SNPs) for this gene. Some are nonsynonymous, some occur in the intron region, and some in an untranslated region. Two nonsynonymous SNPs, namely, rs11745088 and rs1127760, were taken for analysis. In the SNP rs11745088, the change is E152Q. Likewise, in rs1127760, the change is C239S. SIFT (Sorting Intolerant from Tolerant) showed positions of amino acids and the single letter code of amino acids that can be tolerated or deleterious for each position. There were six SNP results and each result had links to it. The dbSNP id, primary database id, and the type of mutation whether silent and if occurring in coding region are given as phenotype alterations. The FASTA format of protein was given to the nsSNP Analyzer tool, and the variation E152Q and C239S were given as inputs in the SNP data field. E152Q change was neutral and C239S causes disease. Using PANTHER for evolutionary analysis of coding SNPs, the protein sequence was given as input and analyzed for the E152Q and C239S SNPs for deleterious effect on protein function. The genetic association

  15. A gene-based SNP resource and linkage map for the copepod Tigriopus californicus

    PubMed Central

    2011-01-01

    Background As yet, few genomic resources have been developed in crustaceans. This lack is particularly evident in Copepoda, given the extraordinary numerical abundance, and taxonomic and ecological diversity of this group. Tigriopus californicus is ideally suited to serve as a genetic model copepod and has been the subject of extensive work in environmental stress and reproductive isolation. Accordingly, we set out to develop a broadly-useful panel of genetic markers and to construct a linkage map dense enough for quantitative trait locus detection in an interval mapping framework for T. californicus--a first for copepods. Results One hundred and ninety Single Nucleotide Polymorphisms (SNPs) were used to genotype our mapping population of 250 F2 larvae. We were able to construct a linkage map with an average intermarker distance of 1.8 cM, and a maximum intermarker distance of 10.3 cM. All markers were assembled into linkage groups, and the 12 linkage groups corresponded to the 12 known chromosomes of T. californicus. We estimate a total genome size of 401.0 cM, and a total coverage of 73.7%. Seventy five percent of the mapped markers were detected in 9 additional populations of T. californicus. Of available model arthropod genomes, we were able to show more colocalized pairs of homologues between T. californicus and the honeybee Apis mellifera, than expected by chance, suggesting preserved macrosynteny between Hymenoptera and Copepoda. Conclusions Our study provides an abundance of linked markers spanning all chromosomes. Many of these markers are also found in multiple populations of T. californicus, and in two other species in the genus. The genomic resource we have developed will enable mapping throughout the geographical range of this species and in closely related species. This linkage map will facilitate genome sequencing, mapping and assembly in an ecologically and taxonomically interesting group for which genomic resources are currently under development

  16. Gene-based aggregate SNP associations between candidate AD genes and cognitive decline.

    PubMed

    Nettiksimmons, Jasmine; Tranah, Gregory; Evans, Daniel S; Yokoyama, Jennifer S; Yaffe, Kristine

    2016-04-01

    Single nucleotide polymorphisms (SNPs) in and near ABCA7, BIN1, CASS4, CD2AP, CD33, CELF1, CLU, complement receptor 1 (CR1), EPHA1, EXOC3L2, FERMT2, HLA cluster (DRB5-DQA), INPP5D, MEF2C, MS4A cluster (MS4A3-MS4A6E), NME8, PICALM, PTK2B, SLC24A4, SORL1, and ZCWPW1 have been associated with Alzheimer's disease (AD) in large meta-analyses. We aimed to determine whether established AD-associated genes are associated with longitudinal cognitive decline by examining aggregate variation across these gene regions. In two single-sex cohorts of older, community-dwelling adults, we examined the association between SNPs in previously implicated gene regions and cognitive decline (age-adjusted person-specific cognitive slopes) using a Sequence Kernel Association Test (SKAT). In regions which showed aggregate significance, we examined the univariate association between individual SNPs in the region and cognitive decline. Only two of the original AD-associated SNPs were significantly associated with cognitive decline in our cohorts. We identified significant aggregate-level associations between cognitive decline and the gene regions BIN1, CD33, CELF1, CR1, HLA cluster, and MEF2C in the all-female cohort and significant associations with ABCA7, HLA cluster, MS4A6E, PICALM, PTK2B, SLC24A4, and SORL1 in the all-male cohort. We also identified a block of eight correlated SNPs in CD33 and several blocks of correlated SNPs in CELF1 that were significantly associated with cognitive decline in univariate analysis in the all-female cohort. PMID:27005436

  17. Identification of rheumatoid arthritis biomarkers based on single nucleotide polymorphisms and haplotype blocks: A systematic review and meta-analysis

    PubMed Central

    Saad, Mohamed N.; Mabrouk, Mai S.; Eldeib, Ayman M.; Shaker, Olfat G.

    2015-01-01

    Genetics of autoimmune diseases represent a growing domain with surpassing biomarker results with rapid progress. The exact cause of Rheumatoid Arthritis (RA) is unknown, but it is thought to have both a genetic and an environmental bases. Genetic biomarkers are capable of changing the supervision of RA by allowing not only the detection of susceptible individuals, but also early diagnosis, evaluation of disease severity, selection of therapy, and monitoring of response to therapy. This review is concerned with not only the genetic biomarkers of RA but also the methods of identifying them. Many of the identified genetic biomarkers of RA were identified in populations of European and Asian ancestries. The study of additional human populations may yield novel results. Most of the researchers in the field of identifying RA biomarkers use single nucleotide polymorphism (SNP) approaches to express the significance of their results. Although, haplotype block methods are expected to play a complementary role in the future of that field. PMID:26843965

  18. Transcriptome and Complexity-Reduced, DNA-Based Identification of Intraspecies Single-Nucleotide Polymorphisms in the Polyploid Gossypium hirsutum L.

    PubMed Central

    Zhu, Qian-Hao; Spriggs, Andrew; Taylor, Jennifer M.; Llewellyn, Danny; Wilson, Iain

    2014-01-01

    Varietal single nucleotide polymorphisms (SNPs) are the differences within one of the two subgenomes between different tetraploid cotton varieties and have not been practically used in cotton genetics and breeding because they are difficult to identify due to low genetic diversity and very high sequence identity between homeologous genes in cotton. We have used transcriptome and restriction site−associated DNA sequencing to identify varietal SNPs among 18 G. hirsutum varieties based on the rationale that varietal SNPs can be more confidently called when flanked by subgenome-specific SNPs. Using transcriptome data, we successfully identified 37,413 varietal SNPs and, of these, 22,121 did not have an additional varietal SNP within their 20-bp flanking regions so can be used in most SNP genotyping assays. From restriction site−associated DNA sequencing data, we identified an additional 3090 varietal SNPs between two of the varieties. Of the 1583 successful SNP assays achieved using different genotyping platforms, 1363 were verified. Many of the SNPs behaved as dominant markers because of coamplification from homeologous loci, but the number of SNPs acting as codominant markers increased when one or more subgenome-specific SNP(s) were incorporated in their assay primers, giving them greater utility for breeding applications. A G. hirsutum genetic map with 1244 SNP markers was constructed covering 5557.42 centiMorgan and used to map qualitative and quantitative traits. This collection of G. hirsutum varietal SNPs complements existing intra-specific SNPs and provides the cotton community with a valuable marker resource applicable to genetic analyses and breeding programs. PMID:25106949

  19. [A comparative study on genetic polymorphism and genetic relationship of 13 SNPs in three Chinese populations].

    PubMed

    Wang, Rui-Heng; Liu, Li-Min; Zhao, Jin-Ling

    2009-03-01

    Using the fluorescence labeled capillary electrophoresis of multi-PCR technique, the single nucleotide polymorphism (SNP) typing system of fragment length discrepant allele specific fluorescence labeled multi-PCR technique is established based on the principle of allele-specific PCR. The typing of the 13 SNP loci can be completed simultaneously according to the length of PCR products and the number of product peaks. It appears a single product peak when the SNP is homozygous, and two product peaks with 4 bp differences will appear when it is heterozygous. By using this system, we conducted population census about allele frequencies for 13 autosomal SNP loci in Southern Liaoning Han samples, Mongolian samples in Inner Mongolia and Zhuang samples in Guangxi area, and got the allele frequencies of the 13 SNP loci in the three populations, then preliminarily discussed their genetic relationship by comparing their differences in allelic polymorphism. The results indicate that the allelic distributions of the 13 SNP loci in the three populations are polymorphic, and the difference is significant in some SNP loci (P< or =0.01). The sampling survey shows that the result is consistent with Hardy-Weinberg equilibrium, and Han population in southern Liaoning has relatively closer relationship with Mongolian in Inner Mongolia than with Zhuang population in Guangxi by origin. PMID:19273440

  20. Chemiluminescence resonance energy transfer imaging on magnetic particles for single-nucleotide polymorphism detection based on ligation chain reaction.

    PubMed

    Bi, Sai; Zhang, Zhipeng; Dong, Ying; Wang, Zonghua

    2015-03-15

    A novel ligation chain reaction (LCR) methodology for single-nucleotide polymorphism (SNP) detection was developed based on luminol-H2O2-horseradish peroxidase (HRP)-mimicking DNAzyme-fluorescein chemiluminescence resonance energy transfer (CRET) imaging on magnetic particles. For LCR, four unique target-complement probes (X and X(⁎), YG and Y(⁎)) for the amplification of K-ras (G12C) were designed by modifying G-quadruplex sequence at 3'-end of YG and fluorescein at 5'-end of Y(⁎). After the LCR, the resulting products of XYG/X(⁎)Y(⁎) with biotin-labeled X(⁎) were captured onto streptavidin-coated magnetic particles (SA-MPs) via specific biotin-SA interaction, which stimulated the CRET reaction from hemin/G-quadruplex-catalyzed luminol-H2O2 CL system to fluorescein. By collecting signals by a cooled low-light CCD, a CRET imaging method was proposed for visual detection and quantitative analysis of SNP. As low as 0.86fM mutant DNA was detected by this assay, and positive mutation detection was achieved with a wild-type to mutant ratio of 10,000:1. This high sensitivity and specificity could be attributed to not only the exponential amplification and excellent discrimination of LCR but also the employment of SA-MPs. SA-MPs ensured the feasibility of the proposed strategy, which also simplified the operations through magnetic separation and separated the reaction and detection procedures to improve sensitivity. The proposed LCR-CRET imaging strategy extends the application of signal amplification techniques to SNP detection, providing a promising platform for effective and high-throughput genetic diagnosis. PMID:25461149

  1. Flow-cytometry-based DNA hybidization and polymorphism analysis

    NASA Astrophysics Data System (ADS)

    Cai, Hong; Kommander, Kristina; White, P. S.; Nolan, John P.

    1998-05-01

    Functional analysis of the human genome, including the quantification of differential gene expression and the identification of polymorphic sites and disease genes, is an important element of the Human Genome Project. Current methods of analysis are mainly gel-based assays that are not well- suited to rapid genome-scale analyses. To analyze DNA sequence on a large scale, robust and high throughput assays are needed. We are developing a suite of microsphere-based approaches employing fluorescence detection to screen and analyze genomic sequence. Our approaches include competitive DNA hybridization to measure DNA or RNA targets in unknown samples, and oligo ligation or extension assays to analyze single-nucleotide polymorphisms. Apart from the advantages of sensitivity, simplicity, and low sample consumption, these flow cytometric approaches have the potential for high throughput multiplexed analysis using multicolored microspheres and automated sample handling.

  2. PTEN polymorphisms contribute to clinical outcomes of advanced lung adenocarcinoma patients treated with platinum-based chemotherapy.

    PubMed

    Yang, Yang; Xu, Wen; Liu, Di; Ding, Xi; Su, Bo; Sun, Yifeng; Gao, Wen

    2016-06-01

    This study aimed to elucidate the impact of PTEN single nucleotide polymorphism (SNP) on clinical outcomes for advanced lung adenocarcinoma (LAC) patients treated with platinum-based chemotherapy. Three functional SNPs (rs11202607 G>A, rs701848 A>G, and rs11202592 G>C) of PTEN gene were genotyped by using DNA from blood samples of 618 advanced LAC patients, and their relationships with clinical outcomes were analyzed. The carriers of homozygous mutant of rs701848 and rs11202592 polymorphisms revealed significantly worse overall survival (OS) than those with heterozygote or wild-type homozygote (18.83 vs. 21.47 vs. 24.37 months, P = 0.034 and 13.40 vs. 19.03 vs. 21.90 months, P = 0.025, respectively). Subgroup analysis revealed that this association was particularly significant in tumor-lymph-node metastasis (TNM) stage III patients. The objective response rates (ORR) and disease control rates (DCR) of patients with genotype AA, AG, and GG in PTEN rs701848 polymorphism were statistically different (24.1 vs 16.6 vs 12.2 %, P = 0.017 and 82.7 vs 76.0 vs 70.2 %, P = 0.029, respectively). Haplotype analysis revealed a protective effect of the haplotype G-A-A (in the order of rs11202592, rs701848, and rs11202607) on chemotherapy efficacy and survival. Taken together, PTEN polymorphisms may contribute to survival and chemotherapy efficacy of advanced LAC patients treated with platinum-based agents. PMID:26695147

  3. SNP-Based QTL Mapping of 15 Complex Traits in Barley under Rain-Fed and Well-Watered Conditions by a Mixed Modeling Approach

    PubMed Central

    Mora, Freddy; Quitral, Yerko A.; Matus, Ivan; Russell, Joanne; Waugh, Robbie; del Pozo, Alejandro

    2016-01-01

    This study identified single nucleotide polymorphism (SNP) markers associated with 15 complex traits in a breeding population of barley (Hordeum vulgare L.) consisting of 137 recombinant chromosome substitution lines (RCSL), evaluated under contrasting water availability conditions in the Mediterranean climatic region of central Chile. Given that markers showed a very strong segregation distortion, a quantitative trait locus/loci (QTL) mapping mixed model was used to account for the heterogeneity in genetic relatedness between genotypes. Fifty-seven QTL were detected under rain-fed conditions, which accounted for 5–22% of the phenotypic variation. In full irrigation conditions, 84 SNPs were significantly associated with the traits studied, explaining 5–35% of phenotypic variation. Most of the QTL were co-localized on chromosomes 2H and 3H. Environment-specific genomic regions were detected for 12 of the 15 traits scored. Although most QTL-trait associations were environment and trait specific, some important and stable associations were also detected. In full irrigation conditions, a relatively major genomic region was found underlying hectoliter weight (HW), on chromosome 1H, which explained between 27% (SNP 2711-234) and 35% (SNP 1923-265) of the phenotypic variation. Interestingly, the locus 1923-265 was also detected for grain yield at both environmental conditions, accounting for 9 and 18%, in the rain-fed and irrigation conditions, respectively. Analysis of QTL in this breeding population identified significant genomic regions that can be used for marker-assisted selection (MAS) of barley in areas where drought is a significant constraint. PMID:27446139

  4. SNP-Based QTL Mapping of 15 Complex Traits in Barley under Rain-Fed and Well-Watered Conditions by a Mixed Modeling Approach.

    PubMed

    Mora, Freddy; Quitral, Yerko A; Matus, Ivan; Russell, Joanne; Waugh, Robbie; Del Pozo, Alejandro

    2016-01-01

    This study identified single nucleotide polymorphism (SNP) markers associated with 15 complex traits in a breeding population of barley (Hordeum vulgare L.) consisting of 137 recombinant chromosome substitution lines (RCSL), evaluated under contrasting water availability conditions in the Mediterranean climatic region of central Chile. Given that markers showed a very strong segregation distortion, a quantitative trait locus/loci (QTL) mapping mixed model was used to account for the heterogeneity in genetic relatedness between genotypes. Fifty-seven QTL were detected under rain-fed conditions, which accounted for 5-22% of the phenotypic variation. In full irrigation conditions, 84 SNPs were significantly associated with the traits studied, explaining 5-35% of phenotypic variation. Most of the QTL were co-localized on chromosomes 2H and 3H. Environment-specific genomic regions were detected for 12 of the 15 traits scored. Although most QTL-trait associations were environment and trait specific, some important and stable associations were also detected. In full irrigation conditions, a relatively major genomic region was found underlying hectoliter weight (HW), on chromosome 1H, which explained between 27% (SNP 2711-234) and 35% (SNP 1923-265) of the phenotypic variation. Interestingly, the locus 1923-265 was also detected for grain yield at both environmental conditions, accounting for 9 and 18%, in the rain-fed and irrigation conditions, respectively. Analysis of QTL in this breeding population identified significant genomic regions that can be used for marker-assisted selection (MAS) of barley in areas where drought is a significant constraint. PMID:27446139

  5. A SNP discovery method to assess variant allele probability from next-generation resequencing data

    PubMed Central

    Shen, Yufeng; Wan, Zhengzheng; Coarfa, Cristian; Drabek, Rafal; Chen, Lei; Ostrowski, Elizabeth A.; Liu, Yue; Weinstock, George M.; Wheeler, David A.; Gibbs, Richard A.; Yu, Fuli

    2010-01-01

    Accurate identification of genetic variants from next-generation sequencing (NGS) data is essential for immediate large-scale genomic endeavors such as the 1000 Genomes Project, and is crucial for further genetic analysis based on the discoveries. The key challenge in single nucleotide polymorphism (SNP) discovery is to distinguish true individual variants (occurring at a low frequency) from sequencing errors (often occurring at frequencies orders of magnitude higher). Therefore, knowledge of the error probabilities of base calls is essential. We have developed Atlas-SNP2, a computational tool that detects and accounts for systematic sequencing errors caused by context-related variables in a logistic regression model learned from training data sets. Subsequently, it estimates the posterior error probability for each substitution through a Bayesian formula that integrates prior knowledge of the overall sequencing error probability and the estimated SNP rate with the results from the logistic regression model for the given substitutions. The estimated posterior SNP probability can be used to distinguish true SNPs from sequencing errors. Validation results show that Atlas-SNP2 achieves a false-positive rate of lower than 10%, with an ∼5% or lower false-negative rate. PMID:20019143

  6. Development of a SNP genotyping panel for genetic monitoring of the laboratory mouse.

    PubMed

    Petkov, Petko M; Cassell, Megan A; Sargent, Evelyn E; Donnelly, Charles J; Robinson, Phil; Crew, Victor; Asquith, Steven; Haar, Raymond Vonder; Wiles, Michael V

    2004-05-01

    We have developed a genotyping system for detecting genetic contamination in the laboratory mouse based on assaying single-nucleotide polymorphism (SNP) markers positioned on all autosomes and the X chromosome. This system provides a fast, reliable, and cost-effective way for genetic monitoring, while maintaining a very high degree of confidence. We describe the allelic distribution of 235 SNPs in 48 mouse strains, thereby creating a database of polymorphisms useful for genotyping purposes. The SNP markers used in this study were chosen from publicly available SNP databases. Four genotyping methods were evaluated, and dynamic two-tube allele-specific PCR assays were developed for each marker and tested on a set of 48 inbred mouse strains. The minimal number of assays sufficient to distinguish groups consisting of different numbers of mouse strains was estimated, and a panel of 28 SNPs sufficient to distinguish virtually all of the inbred strains tested was selected. Amplifluor SNP detection assays were developed for these markers and tested on an extended list of 96 strains. This panel was used as a genetic quality control approach to monitor the genotypes of nearly 300 inbred, wild-derived, congenic, consomic, and recombinant inbred strains maintained at The Jackson Laboratory. We have concluded that this marker panel is sufficient for genetic contamination monitoring in colonies containing a large number of genetically diverse mouse strains and that reduced versions of the panel could be implemented in facilities housing a lower number of strains. PMID:15081119

  7. Dopaminergic Genetic Polymorphisms Predict Rule-based Category Learning.

    PubMed

    Byrne, Kaileigh A; Davis, Tyler; Worthy, Darrell A

    2016-07-01

    Dopaminergic genes play an important role in cognitive function. DRD2 and DARPP-32 dopamine receptor gene polymorphisms affect striatal dopamine binding potential, and the Val158Met single-nucleotide polymorphism of the COMT gene moderates dopamine availability in the pFC. Our study assesses the role of these gene polymorphisms on performance in two rule-based category learning tasks. Participants completed unidimensional and conjunctive rule-based tasks. In the unidimensional task, a rule along a single stimulus dimension can be used to distinguish category members. In contrast, a conjunctive rule utilizes a combination of two dimensions to distinguish category members. DRD2 C957T TT homozygotes outperformed C allele carriers on both tasks, and DARPP-32 AA homozygotes outperformed G allele carriers on both tasks. However, we found an interaction between COMT and task type where Met allele carriers outperformed Val homozygotes in the conjunctive rule task, but both groups performed equally well in the unidimensional task. Thus, striatal dopamine binding may play a critical role in both types of rule-based tasks, whereas prefrontal dopamine binding is important for learning more complex conjunctive rule tasks. Modeling results suggest that striatal dopaminergic genes influence selective attention processes whereas cortical genes mediate the ability to update complex rule representations. PMID:26918585

  8. SNP-SNP interaction analysis of NF-κB signaling pathway on breast cancer survival.

    PubMed

    Jamshidi, Maral; Fagerholm, Rainer; Khan, Sofia; Aittomäki, Kristiina; Czene, Kamila; Darabi, Hatef; Li, Jingmei; Andrulis, Irene L; Chang-Claude, Jenny; Devilee, Peter; Fasching, Peter A; Michailidou, Kyriaki; Bolla, Manjeet K; Dennis, Joe; Wang, Qin; Guo, Qi; Rhenius, Valerie; Cornelissen, Sten; Rudolph, Anja; Knight, Julia A; Loehberg, Christian R; Burwinkel, Barbara; Marme, Frederik; Hopper, John L; Southey, Melissa C; Bojesen, Stig E; Flyger, Henrik; Brenner, Hermann; Holleczek, Bernd; Margolin, Sara; Mannermaa, Arto; Kosma, Veli-Matti; Van Dyck, Laurien; Nevelsteen, Ines; Couch, Fergus J; Olson, Janet E; Giles, Graham G; McLean, Catriona; Haiman, Christopher A; Henderson, Brian E; Winqvist, Robert; Pylkäs, Katri; Tollenaar, Rob A E M; García-Closas, Montserrat; Figueroa, Jonine; Hooning, Maartje J; Martens, John W M; Cox, Angela; Cross, Simon S; Simard, Jacques; Dunning, Alison M; Easton, Douglas F; Pharoah, Paul D P; Hall, Per; Blomqvist, Carl; Schmidt, Marjanka K; Nevanlinna, Heli

    2015-11-10

    In breast cancer, constitutive activation of NF-κB has been reported, however, the impact of genetic variation of the pathway on patient prognosis has been little studied. Furthermore, a combination of genetic variants, rather than single polymorphisms, may affect disease prognosis. Here, in an extensive dataset (n = 30,431) from the Breast Cancer Association Consortium, we investigated the association of 917 SNPs in 75 genes in the NF-κB pathway with breast cancer prognosis. We explored SNP-SNP interactions on survival using the likelihood-ratio test comparing multivariate Cox' regression models of SNP pairs without and with an interaction term. We found two interacting pairs associating with prognosis: patients simultaneously homozygous for the rare alleles of rs5996080 and rs7973914 had worse survival (HRinteraction 6.98, 95% CI=3.3-14.4, P=1.42E-07), and patients carrying at least one rare allele for rs17243893 and rs57890595 had better survival (HRinteraction 0.51, 95% CI=0.3-0.6, P = 2.19E-05). Based on in silico functional analyses and literature, we speculate that the rs5996080 and rs7973914 loci may affect the BAFFR and TNFR1/TNFR3 receptors and breast cancer survival, possibly by disturbing both the canonical and non-canonical NF-κB pathways or their dynamics, whereas, rs17243893-rs57890595 interaction on survival may be mediated through TRAF2-TRAIL-R4 interplay. These results warrant further validation and functional analyses. PMID:26317411

  9. SNP-SNP interaction analysis of NF-κB signaling pathway on breast cancer survival

    PubMed Central

    Jamshidi, Maral; Fagerholm, Rainer; Khan, Sofia; Aittomäki, Kristiina; Czene, Kamila; Darabi, Hatef; Li, Jingmei; Andrulis, Irene L.; Chang-Claude, Jenny; Devilee, Peter; Fasching, Peter A.; Michailidou, Kyriaki; Bolla, Manjeet K.; Dennis, Joe; Wang, Qin; Guo, Qi; Rhenius, Valerie; Cornelissen, Sten; Rudolph, Anja; Knight, Julia A.; Loehberg, Christian R.; Burwinkel, Barbara; Marme, Frederik; Hopper, John L.; Southey, Melissa C.; Bojesen, Stig E.; Flyger, Henrik; Brenner, Hermann; Holleczek, Bernd; Margolin, Sara; Mannermaa, Arto; Kosma, Veli-Matti; Dyck, Laurien Van; Nevelsteen, Ines; Couch, Fergus J.; Olson, Janet E.; Giles, Graham G.; McLean, Catriona; Haiman, Christopher A.; Henderson, Brian E.; Winqvist, Robert; Pylkäs, Katri; Tollenaar, Rob A.E.M.; García-Closas, Montserrat; Figueroa, Jonine; Hooning, Maartje J.; Martens, John W.M.; Cox, Angela; Cross, Simon S.; Simard, Jacques; Dunning, Alison M.; Easton, Douglas F.; Pharoah, Paul D.P.; Hall, Per; Blomqvist, Carl; Schmidt, Marjanka K.; Nevanlinna, Heli

    2015-01-01

    In breast cancer, constitutive activation of NF-κB has been reported, however, the impact of genetic variation of the pathway on patient prognosis has been little studied. Furthermore, a combination of genetic variants, rather than single polymorphisms, may affect disease prognosis. Here, in an extensive dataset (n = 30,431) from the Breast Cancer Association Consortium, we investigated the association of 917 SNPs in 75 genes in the NF-κB pathway with breast cancer prognosis. We explored SNP-SNP interactions on survival using the likelihood-ratio test comparing multivariate Cox’ regression models of SNP pairs without and with an interaction term. We found two interacting pairs associating with prognosis: patients simultaneously homozygous for the rare alleles of rs5996080 and rs7973914 had worse survival (HRinteraction 6.98, 95% CI=3.3-14.4, P = 1.42E-07), and patients carrying at least one rare allele for rs17243893 and rs57890595 had better survival (HRinteraction 0.51, 95% CI=0.3-0.6, P = 2.19E-05). Based on in silico functional analyses and literature, we speculate that the rs5996080 and rs7973914 loci may affect the BAFFR and TNFR1/TNFR3 receptors and breast cancer survival, possibly by disturbing both the canonical and non-canonical NF-κB pathways or their dynamics, whereas, rs17243893-rs57890595 interaction on survival may be mediated through TRAF2-TRAIL-R4 interplay. These results warrant further validation and functional analyses. PMID:26317411

  10. SNP annotation-based whole genomic prediction and selection: an application to feed efficiency and its component traits in pigs.

    PubMed

    Do, D N; Janss, L L G; Jensen, J; Kadarmideen, H N

    2015-05-01

    The study investigated genetic architecture and predictive ability using genomic annotation of residual feed intake (RFI) and its component traits (daily feed intake [DFI], ADG, and back fat [BF]). A total of 1,272 Duroc pigs had both genotypic and phenotypic records, and the records were split into a training (968 pigs) and a validation dataset (304 pigs) by assigning records as before and after January 1, 2012, respectively. SNP were annotated by 14 different classes using Ensembl variant effect prediction. Predictive accuracy and prediction bias were calculated using Bayesian Power LASSO, Bayesian A, B, and Cπ, and genomic BLUP (GBLUP) methods. Predictive accuracy ranged from 0.508 to 0.531, 0.506 to 0.532, 0.276 to 0.357, and 0.308 to 0.362 for DFI, RFI, ADG, and BF, respectively. BayesCπ100.1 increased accuracy slightly compared to the GBLUP model and other methods. The contribution per SNP to total genomic variance was similar among annotated classes across different traits. Predictive performance of SNP classes did not significantly differ from randomized SNP groups. Genomic prediction has accuracy comparable to observed phenotype, and use of genomic prediction can be cost effective by replacing feed intake measurement. Genomic annotation had less impact on predictive accuracy traits considered here but may be different for other traits. It is the first study to provide useful insights into biological classes of SNP driving the whole genomic prediction for complex traits in pigs. PMID:26020301

  11. Different SNP combinations in the GCH1 gene and use of labor analgesia

    PubMed Central

    2010-01-01

    Background The aim of this study was to investigate if there is an association between different SNP combinations in the guanosine triphosphate cyclohydrolase (GCH1) gene and a number of pain behavior related outcomes during labor. A population-based sample of pregnant women (n = 814) was recruited at gestational week 18. A plasma sample was collected from each subject. Genotyping was performed and three single nucleotide polymorphisms (SNP) previously defined as a pain-protective SNP combination of GCH1 were used. Results Homozygous carriers of the pain-protective SNP combination of GCH1 arrived to the delivery ward with a more advanced stage of cervical dilation compared to heterozygous carriers and non-carriers. However, homozygous carriers more often used second line labor analgesia compared to the others. Conclusion The pain-protective SNP combination of GCH1 may be of importance in the limited number of homozygous carriers during the initial dilation of cervix but upon arrival at the delivery unit these women are more inclined to use second line labor analgesia. PMID:20633294

  12. Simple SNP-based minimal marker genotyping for (Humulus lupulus L.) identification and variety validation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hop is a perennial crop with clonal propagation system for varietal distribution. Brewers and growers are highly concerned about variety purity and regularly seek genotype testing. Current means for genotyping are based upon SSRs OR AFLPs that are relatively accurate but cannot differentiate close...

  13. Development Of Interspecific Cssls In Rice Using SNP-Based Selection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Six libraries of chromosome segment substitution lines (CSSLs) are being developed based on crosses between three diverse accessions of O. rufipogon (from China, Laos and Indonesia) and two O. sativa recurrent parents, IR64, an indica variety (from the Philippines), and Cybonnet, a tropical japonica...

  14. A Novel 7-Single Nucleotide Polymorphism-Based Clonotyping Test Allows Rapid Prediction of Antimicrobial Susceptibility of Extraintestinal Escherichia coli Directly From Urine Specimens

    PubMed Central

    Tchesnokova, Veronika; Avagyan, Hovhannes; Billig, Mariya; Chattopadhyay, Sujay; Aprikian, Pavel; Chan, Diana; Pseunova, Julietta; Rechkina, Elena; Riddell, Kim; Scholes, Delia; Fang, Ferric C.; Johnson, James R.; Sokurenko, Evgeni V.

    2016-01-01

    Background. Escherichia coli is a highly clonal pathogen. Extraintestinal isolates belong to a limited number of genetically related groups, which often exhibit characteristic antimicrobial resistance profiles. Methods. We developed a rapid clonotyping method for extraintestinal E coli based on detection of the presence or absence of 7 single nucleotide polymorphisms (SNPs) within 2 genes (fumC and fimH). A reference set of 2559 E coli isolates, primarily of urinary origin, was used to predict the resolving power of the 7-SNP-based typing method, and 582 representative strains from this set were used to evaluate test robustness. Results. Fifty-four unique SNP combinations (“septatypes”) were identified in the reference strains. These septatypes yielded a clonal group resolution power on par with that of traditional multilocus sequence typing. In 72% of isolates, septatype identity predicted sequence type identity with at least 90% (mean, 97%) accuracy. Most septatypes exhibited highly distinctive antimicrobial susceptibility profiles. The 7-SNP-based test could be performed with high specificity and sensitivity using single or multiplex conventional polymerase chain reaction (PCR) and quantitative PCR. In the latter format, E coli presence and septatype identity were determined directly in urine specimens within 45 minutes with bacterial loads as low as 102 colony-forming units/mL and, at clinically significant bacterial loads, with 100% sensitivity and specificity. Conclusions. 7-SNP-based typing of E coli can be used for both epidemiological studies and clinical diagnostics, which could greatly improve the empirical selection of antimicrobial therapy. PMID:26925427

  15. Whole genome single nucleotide polymorphism based phylogeny of Francisella tularensis and its application to the development of a strain typing assay

    PubMed Central

    2009-01-01

    Background A low genetic diversity in Francisella tularensis has been documented. Current DNA based genotyping methods for typing F. tularensis offer a limited and varying degree of subspecies, clade and strain level discrimination power. Whole genome sequencing is the most accurate and reliable method to identify, type and determine phylogenetic relationships among strains of a species. However, lower cost typing schemes are necessary in order to enable typing of hundreds or even thousands of isolates. Results We have generated a high-resolution phylogenetic tree from 40 Francisella isolates, including 13 F. tularensis subspecies holarctica (type B) strains, 26 F. tularensis subsp. tularensis (type A) strains and a single F. novicida strain. The tree was generated from global multi-strain single nucleotide polymorphism (SNP) data collected using a set of six Affymetrix GeneChip® resequencing arrays with the non-repetitive portion of LVS (type B) as the reference sequence complemented with unique sequences of SCHU S4 (type A). Global SNP based phylogenetic clustering was able to resolve all non-related strains. The phylogenetic tree was used to guide the selection of informative SNPs specific to major nodes in the tree for development of a genotyping assay for identification of F. tularensis subspecies and clades. We designed and validated an assay that uses these SNPs to accurately genotype 39 additional F. tularensis strains as type A (A1, A2, A1a or A1b) or type B (B1 or B2). Conclusion Whole-genome SNP based clustering was shown to accurately identify SNPs for differentiation of F. tularensis subspecies and clades, emphasizing the potential power and utility of this methodology for selecting SNPs for typing of F. tularensis to the strain level. Additionally, whole genome sequence based SNP information gained from a representative population of strains may be used to perform evolutionary or phylogenetic comparisons of strains, or selection of unique strains for

  16. The rs2910164:G>C SNP in the MIR146A gene is not associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers.

    PubMed

    Garcia, Amandine I; Cox, David G; Barjhoux, Laure; Verny-Pierre, Carole; Barnes, Daniel; Antoniou, Antonis C; Stoppa-Lyonnet, Dominique; Sinilnikova, Olga M; Mazoyer, Sylvie

    2011-09-01

    The rs2910164:G>C SNP is located in the gene for miR-146a, a microRNA that binds the 3' UTR of the BRCA1 transcript. Preliminary data based on the analysis of a small number of cases suggested that this single nucleotide polymorphism (SNP) might be associated with the age of onset of familial breast and ovarian cancer. This effect was not confirmed on a large series of familial breast cancer cases negative for a BRCA1 or BRCA2 mutation. We show here a lack of association of the rs2910164:G>C SNP with breast cancer risk in a series of 1,166 BRCA1 and 560 BRCA2 mutation carriers. In conclusion, the polymorphism in the miR-146a gene is unlikely to be of substantial significance regarding breast cancer risk. PMID:21591024

  17. Current research status, databases and application of single nucleotide polymorphism.

    PubMed

    Javed, R; Mukesh

    2010-07-01

    Single Nucleotide Polymorphisms (SNPs) are the most frequent form of DNA variation in the genome. SNPs are genetic markers which are bi-allelic in nature and grow at a very fast rate. Current genomic databases contain information on several million SNPs. More than 6 million SNPs have been identified and the information is publicly available through the efforts of the SNP Consortium and others data bases. The NCBI plays a major role in facillating the identification and cataloging of SNPs through creation and maintenance of the public SNP database (dbSNP) by the biomedical community worldwide and stimulate many areas of biological research including the identification of the genetic components of disease. In this review article, we are compiling the existing SNP databases, research status and their application. PMID:21717869

  18. Testing Allele Transmission of an SNP Set Using a Family-Based Generalized Genetic Random Field Method.

    PubMed

    Li, Ming; Li, Jingyun; He, Zihuai; Lu, Qing; Witte, John S; Macleod, Stewart L; Hobbs, Charlotte A; Cleves, Mario A

    2016-05-01

    Family-based association studies are commonly used in genetic research because they can be robust to population stratification (PS). Recent advances in high-throughput genotyping technologies have produced a massive amount of genomic data in family-based studies. However, current family-based association tests are mainly focused on evaluating individual variants one at a time. In this article, we introduce a family-based generalized genetic random field (FB-GGRF) method to test the joint association between a set of autosomal SNPs (i.e., single-nucleotide polymorphisms) and disease phenotypes. The proposed method is a natural extension of a recently developed GGRF method for population-based case-control studies. It models offspring genotypes conditional on parental genotypes, and, thus, is robust to PS. Through simulations, we presented that under various disease scenarios the FB-GGRF has improved power over a commonly used family-based sequence kernel association test (FB-SKAT). Further, similar to GGRF, the proposed FB-GGRF method is asymptotically well-behaved, and does not require empirical adjustment of the type I error rates. We illustrate the proposed method using a study of congenital heart defects with family trios from the National Birth Defects Prevention Study (NBDPS). PMID:27061818

  19. Identification of Laying-Related SNP Markers in Geese Using RAD Sequencing

    PubMed Central

    Yu, ShiGang; Chu, WeiWei; Zhang, LiFan; Han, HouMing; Zhao, RongXue; Wu, Wei; Zhu, JiangNing; Dodson, Michael V.; Wei, Wei; Liu, HongLin; Chen, Jie

    2015-01-01

    Laying performance is an important economical trait of goose production. As laying performance is of low heritability, it is of significance to develop a marker-assisted selection (MAS) strategy for this trait. Definition of sequence variation related to the target trait is a prerequisite of quantitating MAS, but little is presently known about the goose genome, which greatly hinders the identification of genetic markers for the laying traits of geese. Recently developed restriction site-associated DNA (RAD) sequencing is a possible approach for discerning large-scale single nucleotide polymorphism (SNP) and reducing the complexity of a genome without having reference genomic information available. In the present study, we developed a pooled RAD sequencing strategy for detecting geese laying-related SNP. Two DNA pools were constructed, each consisting of equal amounts of genomic DNA from 10 individuals with either high estimated breeding value (HEBV) or low estimated breeding value (LEBV). A total of 139,013 SNP were obtained from 42,291,356 sequences, of which 18,771,943 were for LEBV and 23,519,413 were for HEBV cohorts. Fifty-five SNP which had different allelic frequencies in the two DNA pools were further validated by individual-based AS-PCR genotyping in the LEBV and HEBV cohorts. Ten out of 55 SNP exhibited distinct allele distributions in these two cohorts. These 10 SNP were further genotyped in a goose population of 492 geese to verify the association with egg numbers. The result showed that 8 of 10 SNP were associated with egg numbers. Additionally, liner regression analysis revealed that SNP Record-111407, 106975 and 112359 were involved in a multiplegene network affecting laying performance. We used IPCR to extend the unknown regions flanking the candidate RAD tags. The obtained sequences were subjected to BLAST to retrieve the orthologous genes in either ducks or chickens. Five novel genes were cloned for geese which harbored the candidate laying

  20. Optimal Design of Low-Density SNP Arrays for Genomic Prediction: Algorithm and Applications.

    PubMed

    Wu, Xiao-Lin; Xu, Jiaqi; Feng, Guofei; Wiggans, George R; Taylor, Jeremy F; He, Jun; Qian, Changsong; Qiu, Jiansheng; Simpson, Barry; Walker, Jeremy; Bauck, Stewart

    2016-01-01

    Low-density (LD) single nucleotide polymorphism (SNP) arrays provide a cost-effective solution for genomic prediction and selection, but algorithms and computational tools are needed for the optimal design of LD SNP chips. A multiple-objective, local optimization (MOLO) algorithm was developed for design of optimal LD SNP chips that can be imputed accurately to medium-density (MD) or high-density (HD) SNP genotypes for genomic prediction. The objective function facilitates maximization of non-gap map length and system information for the SNP chip, and the latter is computed either as locus-averaged (LASE) or haplotype-averaged Shannon entropy (HASE) and adjusted for uniformity of the SNP distribution. HASE performed better than LASE with ≤1,000 SNPs, but required considerably more computing time. Nevertheless, the differences diminished when >5,000 SNPs were selected. Optimization was accomplished conditionally on the presence of SNPs that were obligated to each chromosome. The frame location of SNPs on a chip can be either uniform (evenly spaced) or non-uniform. For the latter design, a tunable empirical Beta distribution was used to guide location distribution of frame SNPs such that both ends of each chromosome were enriched with SNPs. The SNP distribution on each chromosome was finalized through the objective function that was locally and empirically maximized. This MOLO algorithm was capable of selecting a set of approximately evenly-spaced and highly-informative SNPs, which in turn led to increased imputation accuracy compared with selection solely of evenly-spaced SNPs. Imputation accuracy increased with LD chip size, and imputation error rate was extremely low for chips with ≥3,000 SNPs. Assuming that genotyping or imputation error occurs at random, imputation error rate can be viewed as the upper limit for genomic prediction error. Our results show that about 25% of imputation error rate was propagated to genomic prediction in an Angus population. The

  1. Identification of Laying-Related SNP Markers in Geese Using RAD Sequencing.

    PubMed

    Yu, ShiGang; Chu, WeiWei; Zhang, LiFan; Han, HouMing; Zhao, RongXue; Wu, Wei; Zhu, JiangNing; Dodson, Michael V; Wei, Wei; Liu, HongLin; Chen, Jie

    2015-01-01

    Laying performance is an important economical trait of goose production. As laying performance is of low heritability, it is of significance to develop a marker-assisted selection (MAS) strategy for this trait. Definition of sequence variation related to the target trait is a prerequisite of quantitating MAS, but little is presently known about the goose genome, which greatly hinders the identification of genetic markers for the laying traits of geese. Recently developed restriction site-associated DNA (RAD) sequencing is a possible approach for discerning large-scale single nucleotide polymorphism (SNP) and reducing the complexity of a genome without having reference genomic information available. In the present study, we developed a pooled RAD sequencing strategy for detecting geese laying-related SNP. Two DNA pools were constructed, each consisting of equal amounts of genomic DNA from 10 individuals with either high estimated breeding value (HEBV) or low estimated breeding value (LEBV). A total of 139,013 SNP were obtained from 42,291,356 sequences, of which 18,771,943 were for LEBV and 23,519,413 were for HEBV cohorts. Fifty-five SNP which had different allelic frequencies in the two DNA pools were further validated by individual-based AS-PCR genotyping in the LEBV and HEBV cohorts. Ten out of 55 SNP exhibited distinct allele distributions in these two cohorts. These 10 SNP were further genotyped in a goose population of 492 geese to verify the association with egg numbers. The result showed that 8 of 10 SNP were associated with egg numbers. Additionally, liner regression analysis revealed that SNP Record-111407, 106975 and 112359 were involved in a multiplegene network affecting laying performance. We used IPCR to extend the unknown regions flanking the candidate RAD tags. The obtained sequences were subjected to BLAST to retrieve the orthologous genes in either ducks or chickens. Five novel genes were cloned for geese which harbored the candidate laying

  2. k-merSNP discovery: Software for alignment-and reference-free scalable SNP discovery, phylogenetics, and annotation for hundreds of microbial genomes

    SciTech Connect

    2014-11-18

    With the flood of whole genome finished and draft microbial sequences, we need faster, more scalable bioinformatics tools for sequence comparison. An algorithm is described to find single nucleotide polymorphisms (SNPs) in whole genome data. It scales to hundreds of bacterial or viral genomes, and can be used for finished and/or draft genomes available as unassembled contigs or raw, unassembled reads. The method is fast to compute, finding SNPs and building a SNP phylogeny in minutes to hours, depending on the size and diversity of the input sequences. The SNP-based trees that result are consistent with known taxonomy and trees determined in other studies. The approach we describe can handle many gigabases of sequence in a single run. The algorithm is based on k-mer analysis.

  3. k-merSNP discovery: Software for alignment-and reference-free scalable SNP discovery, phylogenetics, and annotation for hundreds of microbial genomes

    Energy Science and Technology Software Center (ESTSC)

    2014-11-18

    With the flood of whole genome finished and draft microbial sequences, we need faster, more scalable bioinformatics tools for sequence comparison. An algorithm is described to find single nucleotide polymorphisms (SNPs) in whole genome data. It scales to hundreds of bacterial or viral genomes, and can be used for finished and/or draft genomes available as unassembled contigs or raw, unassembled reads. The method is fast to compute, finding SNPs and building a SNP phylogeny inmore » minutes to hours, depending on the size and diversity of the input sequences. The SNP-based trees that result are consistent with known taxonomy and trees determined in other studies. The approach we describe can handle many gigabases of sequence in a single run. The algorithm is based on k-mer analysis.« less

  4. Vitis Phylogenomics: Hybridization Intensities from a SNP Array Outperform Genotype Calls

    PubMed Central

    Miller, Allison J.; Matasci, Naim; Schwaninger, Heidi; Aradhya, Mallikarjuna K.; Prins, Bernard; Zhong, Gan-Yuan; Simon, Charles; Buckler, Edward S.; Myles, Sean

    2013-01-01

    Understanding relationships among species is a fundamental goal of evolutionary biology. Single nucleotide polymorphisms (SNPs) identified through next generation sequencing and related technologies enable phylogeny reconstruction by providing unprecedented numbers of characters for analysis. One approach to SNP-based phylogeny reconstruction is to identify SNPs in a subset of individuals, and then to compile SNPs on an array that can be used to genotype additional samples at hundreds or thousands of sites simultaneously. Although powerful and efficient, this method is subject to ascertainment bias because applying variation discovered in a representative subset to a larger sample favors identification of SNPs with high minor allele frequencies and introduces bias against rare alleles. Here, we demonstrate that the use of hybridization intensity data, rather than genotype calls, reduces the effects of ascertainment bias. Whereas traditional SNP calls assess known variants based on diversity housed in the discovery panel, hybridization intensity data survey variation in the broader sample pool, regardless of whether those variants are present in the initial SNP discovery process. We apply SNP genotype and hybridization intensity data derived from the Vitis9kSNP array developed for grape to show the effects of ascertainment bias and to reconstruct evolutionary relationships among Vitis species. We demonstrate that phylogenies constructed using hybridization intensities suffer less from the distorting effects of ascertainment bias, and are thus more accurate than phylogenies based on genotype calls. Moreover, we reconstruct the phylogeny of the genus Vitis using hybridization data, show that North American subgenus Vitis species are monophyletic, and resolve several previously poorly known relationships among North American species. This study builds on earlier work that applied the Vitis9kSNP array to evolutionary questions within Vitis vinifera and has general

  5. High-throughput SNP genotyping in Cucurbita pepo for map construction and quantitative trait loci mapping

    PubMed Central

    2012-01-01

    Background Cucurbita pepo is a member of the Cucurbitaceae family, the second- most important horticultural family in terms of economic importance after Solanaceae. The "summer squash" types, including Zucchini and Scallop, rank among the highest-valued vegetables worldwide. There are few genomic tools available for this species. The first Cucurbita transcriptome, along with a large collection of Single Nucleotide Polymorphisms (SNP), was recently generated using massive sequencing. A set of 384 SNP was selected to generate an Illumina GoldenGate assay in order to construct the first SNP-based genetic map of Cucurbita and map quantitative trait loci (QTL). Results We herein present the construction of the first SNP-based genetic map of Cucurbita pepo using a population derived from the cross of two varieties with contrasting phenotypes, representing the main cultivar groups of the species' two subspecies: Zucchini (subsp. pepo) × Scallop (subsp. ovifera). The mapping population was genotyped with 384 SNP, a set of selected EST-SNP identified in silico after massive sequencing of the transcriptomes of both parents, using the Illumina GoldenGate platform. The global success rate of the assay was higher than 85%. In total, 304 SNP were mapped, along with 11 SSR from a previous map, giving a map density of 5.56 cM/marker. This map was used to infer syntenic relationships between C. pepo and cucumber and to successfully map QTL that control plant, flowering and fruit traits that are of benefit to squash breeding. The QTL effects were validated in backcross populations. Conclusion Our results show that massive sequencing in different genotypes is an excellent tool for SNP discovery, and that the Illumina GoldenGate platform can be successfully applied to constructing genetic maps and performing QTL analysis in Cucurbita. This is the first SNP-based genetic map in the Cucurbita genus and is an invaluable new tool for biological research, especially considering that most

  6. Development and Validation of a High-Density SNP Genotyping Array for African Oil Palm.

    PubMed

    Kwong, Qi Bin; Teh, Chee Keng; Ong, Ai Ling; Heng, Huey Ying; Lee, Heng Leng; Mohamed, Mohaimi; Low, Joel Zi-Bin; Apparow, Sukganah; Chew, Fook Tim; Mayes, Sean; Kulaveerasingam, Harikrishna; Tammi, Martti; Appleton, David Ross

    2016-08-01

    High-density single nucleotide polymorphism (SNP) genotyping arrays are powerful tools that can measure the level of genetic polymorphism within a population. To develop a whole-genome SNP array for oil palms, SNP discovery was performed using deep resequencing of eight libraries derived from 132 Elaeis guineensis and Elaeis oleifera palms belonging to 59 origins, resulting in the discovery of >3 million putative SNPs. After SNP filtering, the Illumina OP200K custom array was built with 170 860 successful probes. Phenetic clustering analysis revealed that the array could distinguish between palms of different origins in a way consistent with pedigree records. Genome-wide linkage disequilibrium declined more slowly for the commercial populations (ranging from 120 kb at r(2) = 0.43 to 146 kb at r(2) = 0.50) when compared with the semi-wild populations (19.5 kb at r(2) = 0.22). Genetic fixation mapping comparing the semi-wild and commercial population identified 321 selective sweeps. A genome-wide association study (GWAS) detected a significant peak on chromosome 2 associated with the polygenic component of the shell thickness trait (based on the trait shell-to-fruit; S/F %) in tenera palms. Testing of a genomic selection model on the same trait resulted in good prediction accuracy (r = 0.65) with 42% of the S/F % variation explained. The first high-density SNP genotyping array for oil palm has been developed and shown to be robust for use in genetic studies and with potential for developing early trait prediction to shorten the oil palm breeding cycle. PMID:27112659

  7. Syndrome-based discrimination of single nucleotide polymorphism.

    PubMed

    May, E E; Dolan, P; Crozier, P; Brozik, S

    2006-01-01

    The ability to discriminate nucleic acid sequences is necessary for a wide variety of applications: high throughput screening, distinguishing genetically modified organisms (GMOs), molecular computing, differentiating biological markers, fingerprinting a specific sensor response for complex systems, etc. Hybridization-based target recognition and discrimination is central to the operation of nucleic acid sensor systems. Therefore developing a quantitative correlation between mishybridization events and sensor out put is critical to the accurate interpretation of results. In this work, using experimental data produced by introducing single mutations (single nucleotide polymorphisms, SNPs) in the probe sequence of computational catalytic molecular beacons (deoxyribozyme gates) [1], we investigate coding theory algorithms for uniquely categorizing SNPs based on the calculation of syndromes. PMID:17947098

  8. An integrative segmentation method for detecting germline copy number variations in SNP arrays.

    PubMed

    Shi, Jianxin; Li, Peng

    2012-05-01

    Germline copy number variations (CNVs) are a major source of genetic variation in humans. In large-scale studies of complex diseases, CNVs are usually detected from data generated by single nucleotide polymorphism (SNP) genotyping arrays. In this paper, we develop an integrative segmentation method, SegCNV, for detecting CNVs integrating both log R ratio (LRR) and B allele frequency (BAF). Based on simulation studies, SegCNV had modestly better power to detect deletions and substantially better power to detect duplications compared with circular binary segmentation (CBS) that relies purely on LRRs; and it had better power to detect deletions and a comparable performance to detect duplications compared with PennCNV and QuantiSNP. In two Hapmap subjects with deep sequence data available as a gold standard, SegCNV detected more true short deletions than PennCNV and QuantiSNP. For 21 short duplications validated experimentally in the AGRE dataset, SegCNV, QuantiSNP, and PennCNV detected all of them while CBS detected only three. SegCNV is much faster than the HMM-based (where HMM is hidden Markov model) methods, taking only several seconds to analyze genome-wide data for one subject. PMID:22539397

  9. SNPConvert: SNP Array Standardization and Integration in Livestock Species

    PubMed Central

    Nicolazzi, Ezequiel Luis; Marras, Gabriele; Stella, Alessandra

    2016-01-01

    One of the main advantages of single nucleotide polymorphism (SNP) array technology is providing genotype calls for a specific number of SNP markers at a relatively low cost. Since its first application in animal genetics, the number of available SNP arrays for each species has been constantly increasing. However, conversely to that observed in whole genome sequence data analysis, SNP array data does not have a common set of file formats or coding conventions for allele calling. Therefore, the standardization and integration of SNP array data from multiple sources have become an obstacle, especially for users with basic or no programming skills. Here, we describe the difficulties related to handling SNP array data, focusing on file formats, SNP allele coding, and mapping. We also present SNPConvert suite, a multi-platform, open-source, and user-friendly set of tools to overcome these issues. This tool, which can be integrated with open-source and open-access tools already available, is a first step towards an integrated system to standardize and integrate any type of raw SNP array data. The tool is available at: https://github. com/nicolazzie/SNPConvert.git. PMID:27600083

  10. SNPConvert: SNP Array Standardization and Integration in Livestock Species.

    PubMed

    Nicolazzi, Ezequiel Luis; Marras, Gabriele; Stella, Alessandra

    2016-01-01

    One of the main advantages of single nucleotide polymorphism (SNP) array technology is providing genotype calls for a specific number of SNP markers at a relatively low cost. Since its first application in animal genetics, the number of available SNP arrays for each species has been constantly increasing. However, conversely to that observed in whole genome sequence data analysis, SNP array data does not have a common set of file formats or coding conventions for allele calling. Therefore, the standardization and integration of SNP array data from multiple sources have become an obstacle, especially for users with basic or no programming skills. Here, we describe the difficulties related to handling SNP array data, focusing on file formats, SNP allele coding, and mapping. We also present SNPConvert suite, a multi-platform, open-source, and user-friendly set of tools to overcome these issues. This tool, which can be integrated with open-source and open-access tools already available, is a first step towards an integrated system to standardize and integrate any type of raw SNP array data. The tool is available at: https://github. com/nicolazzie/SNPConvert.git. PMID:27600083

  11. Reexamination of Culex pipiens Hybridization Zone in the Eastern United States by Ribosomal DNA-Based Single Nucleotide Polymorphism Markers

    PubMed Central

    Huang, Shaoming; Molaei, Goudarz; Andreadis, Theodore G.

    2011-01-01

    Mosquitoes in the Culex pipiens complex are important vectors of several disease-causing pathogens, including West Nile virus. In North America, the complex consists of Cx. pipiens pipiens form pipiens, Cx. pipiens pipiens form molestus, Cx. pipiens quinquefasciatus, and their hybrids that exhibit substantial diversity in physiology, behavior, and geographic range. Hybridization among these mosquitoes is of concern because of potential implications for disease transmission. Currently, several morphological and molecular markers exist for differentiating members of the Cx. pipiens complex; however, these markers have specific limitations. We report here two highly reliable ribosomal DNA-based single nucleotide polymorphism (SNP) markers, CxpG2T and CxpA2d, for detecting Cx. pipiens complex mosquitoes containing Cx. p. quinquefasciatus alleles. Both CxpG2T and CxpA2d contain one allele that is present in all members of the Cx. pipiens complex, and the other allele is specific to Cx. p. quinquefasciatus. Testing of field populations from the eastern United States showed that these two SNP markers are capable of identifying a south to north gradient of Cx. p. quinquefasciatus and hybrids. The northern limit of detection of Cx. p. quinquefasciatus alleles in this study was in Fort Totten, NY (40.79°N), whereas the southern boundary was determined between Atlanta, GA (33.81°N) and Gainesville, FL (29.64°N). CxpG2T and CxpA2d were more accurate than the ACE-2 marker, and they may conceivably provide comparable resolution with microsatellite markers for detecting Cx. p. quinquefasciatus alleles. PMID:21896800

  12. PCR-based polymorphisms in neurofibromatosis type 1 (NFI)

    SciTech Connect

    Lai, P.S.; Chee, S.; Low, P.S.

    1994-09-01

    Neurofibromatosis type 1 (NF1) is one of the most common genetic disorders in humans with an incidence of 1 in 3,000. The NF1 gene is located on chromosome 17q 11.2 and encodes an ubiquitously expressed transcript of about 13kb. Direct mutation detection is difficult in this disorder due to the large gene size, high mutation rate and variety of mutations. We have studied the allele frequencies of seven PCR-based polymorphisms. Six of the probes used flank the NF1 gene, namely p11.3C4.2/Msp I (proximal), pEW206/Msp I (distal), p2.f9.8/Rsa I (distal), pEW207/Bgl II (distal), pEW207/Hind III (distal) and pHHH202/Rsa I (proximal). An intragenic RFLP, pEvi 2B-B/Eco R1 polymorphism in intron 27, was also analyzed by PCR. Allele frequencies for 48 normal unrelated individuals were obtained as follows: A1 = 0.40, A2 = 0.6 (p11.3C4.2/Msp I), A1 = 0.44, A2 = 0.56 (pEW206/Msp I), A1 = 0.17, A2 = 0.83 (p2.F9.8/Rsa I), A1 = 0.64, A2 = 0.36 (pEW207/Bgl I), A1 = 0.45, A2 = 0.55 (pEvi 2B-B/Eco RI). Heterozygosity rates of the alleles ranged from 20.8% to 51.7%. Using a combination of these markers, seven local families with NF1 were studied. Normal Mendelian segregation of alleles was observed in these families and no recombination was detected so far. These PCR-based markers were found to be useful for linkage analysis in our families.

  13. Serotyping of Streptococcus pneumoniae Based on Capsular Genes Polymorphisms

    PubMed Central

    Raymond, Frédéric; Boucher, Nancy; Allary, Robin; Robitaille, Lynda; Lefebvre, Brigitte; Tremblay, Cécile

    2013-01-01

    Streptococcus pneumoniae serotype epidemiology is essential since serotype replacement is a concern when introducing new polysaccharide-conjugate vaccines. A novel PCR-based automated microarray assay was developed to assist in the tracking of the serotypes. Autolysin, pneumolysin and eight genes located in the capsular operon were amplified using multiplex PCR. This step was followed by a tagged fluorescent primer extension step targeting serotype-specific polymorphisms. The tagged primers were then hybridized to a microarray. Results were exported to an expert system to identify capsular serotypes. The assay was validated on 166 cultured S. pneumoniae samples from 63 different serotypes as determined by the Quellung method. We show that typing only 12 polymorphisms located in the capsular operon allows the identification at the serotype level of 22 serotypes and the assignation of 24 other serotypes to a subgroup of serotypes. Overall, 126 samples (75.9%) were correctly serotyped, 14 were assigned to a member of the same serogroup, 8 rare serotypes were erroneously serotyped, and 18 gave negative serotyping results. Most of the discrepancies involved rare serotypes or serotypes that are difficult to discriminate using a DNA-based approach, for example 6A and 6B. The assay was also tested on clinical specimens including 43 cerebrospinal fluid samples from patients with meningitis and 59 nasopharyngeal aspirates from bacterial pneumonia patients. Overall, 89% of specimens positive for pneumolysin were serotyped, demonstrating that this method does not require culture to serotype clinical specimens. The assay showed no cross-reactivity for 24 relevant bacterial species found in these types of samples. The limit of detection for serotyping and S. pneumoniae detection was 100 genome equivalent per reaction. This automated assay is amenable to clinical testing and does not require any culturing of the samples. The assay will be useful for the evaluation of serotype

  14. SNP Array in Hematopoietic Neoplasms: A Review

    PubMed Central

    Song, Jinming; Shao, Haipeng

    2015-01-01

    Cytogenetic analysis is essential for the diagnosis and prognosis of hematopoietic neoplasms in current clinical practice. Many hematopoietic malignancies are characterized by structural chromosomal abnormalities such as specific translocations, inversions, deletions and/or numerical abnormalities that can be identified by karyotype analysis or fluorescence in situ hybridization (FISH) studies. Single nucleotide polymorphism (SNP) arrays offer high-resolution identification of copy number variants (CNVs) and acquired copy-neutral loss of heterozygosity (LOH)/uniparental disomy (UPD) that are usually not identifiable by conventional cytogenetic analysis and FISH studies. As a result, SNP arrays have been increasingly applied to hematopoietic neoplasms to search for clinically-significant genetic abnormalities. A large numbers of CNVs and UPDs have been identified in a variety of hematopoietic neoplasms. CNVs detected by SNP array in some hematopoietic neoplasms are of prognostic significance. A few specific genes in the affected regions have been implicated in the pathogenesis and may be the targets for specific therapeutic agents in the future. In this review, we summarize the current findings of application of SNP arrays in a variety of hematopoietic malignancies with an emphasis on the clinically significant genetic variants. PMID:27600067

  15. BAC-End Sequence-Based SNP Mining in Allotetraploid Cotton (Gossypium) Utilizing Resequencing Data, Phylogenetic Inferences, and Perspectives for Genetic Mapping

    PubMed Central

    Hulse-Kemp, Amanda M.; Ashrafi, Hamid; Stoffel, Kevin; Zheng, Xiuting; Saski, Christopher A.; Scheffler, Brian E.; Fang, David D.; Chen, Z. Jeffrey; Van Deynze, Allen; Stelly, David M.

    2015-01-01

    A bacterial artificial chromosome library and BAC-end sequences for cultivated cotton (Gossypium hirsutum L.) have recently been developed. This report presents genome-wide single nucleotide polymorphism (SNP) mining utilizing resequencing data with BAC-end sequences as a reference by alignment of 12 G. hirsutum L. lines, one G. barbadense L. line, and one G. longicalyx Hutch and Lee line. A total of 132,262 intraspecific SNPs have been developed for G. hirsutum, whereas 223,138 and 470,631 interspecific SNPs have been developed for G. barbadense and G. longicalyx, respectively. Using a set of interspecific SNPs, 11 randomly selected and 77 SNPs that are putatively associated with the homeologous chromosome pair 12 and 26, we mapped 77 SNPs into two linkage groups representing these chromosomes, spanning a total of 236.2 cM in an interspecific F2 population (G. barbadense 3-79 × G. hirsutum TM-1). The mapping results validated the approach for reliably producing large numbers of both intraspecific and interspecific SNPs aligned to BAC-ends. This will allow for future construction of high-density integrated physical and genetic maps for cotton and other complex polyploid genomes. The methods developed will allow for future Gossypium resequencing data to be automatically genotyped for identified SNPs along the BAC-end sequence reference for anchoring sequence assemblies and comparative studies. PMID:25858960

  16. BAC-End Sequence-Based SNP Mining in Allotetraploid Cotton (Gossypium) Utilizing Resequencing Data, Phylogenetic Inferences, and Perspectives for Genetic Mapping.

    PubMed

    Hulse-Kemp, Amanda M; Ashrafi, Hamid; Stoffel, Kevin; Zheng, Xiuting; Saski, Christopher A; Scheffler, Brian E; Fang, David D; Chen, Z Jeffrey; Van Deynze, Allen; Stelly, David M

    2015-06-01

    A bacterial artificial chromosome library and BAC-end sequences for cultivated cotton (Gossypium hirsutum L.) have recently been developed. This report presents genome-wide single nucleotide polymorphism (SNP) mining utilizing resequencing data with BAC-end sequences as a reference by alignment of 12 G. hirsutum L. lines, one G. barbadense L. line, and one G. longicalyx Hutch and Lee line. A total of 132,262 intraspecific SNPs have been developed for G. hirsutum, whereas 223,138 and 470,631 interspecific SNPs have been developed for G. barbadense and G. longicalyx, respectively. Using a set of interspecific SNPs, 11 randomly selected and 77 SNPs that are putatively associated with the homeologous chromosome pair 12 and 26, we mapped 77 SNPs into two linkage groups representing these chromosomes, spanning a total of 236.2 cM in an interspecific F2 population (G. barbadense 3-79 × G. hirsutum TM-1). The mapping results validated the approach for reliably producing large numbers of both intraspecific and interspecific SNPs aligned to BAC-ends. This will allow for future construction of high-density integrated physical and genetic maps for cotton and other complex polyploid genomes. The methods developed will allow for future Gossypium resequencing data to be automatically genotyped for identified SNPs along the BAC-end sequence reference for anchoring sequence assemblies and comparative studies. PMID:25858960

  17. Genotyping by Sequencing for SNP-Based Linkage Map Construction and QTL Analysis of Chilling Requirement and Bloom Date in Peach [Prunus persica (L.) Batsch].

    PubMed

    Bielenberg, Douglas Gary; Rauh, Bradley; Fan, Shenghua; Gasic, Ksenija; Abbott, Albert Glenn; Reighard, Gregory Lynn; Okie, William R; Wells, Christina Elizabeth

    2015-01-01

    Low-cost, high throughput genotyping methods are crucial to marker discovery and marker-assisted breeding efforts, but have not been available for many 'specialty crops' such as fruit and nut trees. Here we apply the Genotyping-By-Sequencing (GBS) method developed for cereals to the discovery of single nucleotide polymorphisms (SNPs) in a peach F2 mapping population. Peach is a genetic and genomic model within the Rosaceae and will provide a template for the use of this method with other members of this family. Our F2 mapping population of 57 genotypes segregates for bloom time (BD) and chilling requirement (CR) and we have extensively phenotyped this population. The population derives from a selfed F1 progeny of a cross between 'Hakuho' (high CR) and 'UFGold' (low CR). We were able to successfully employ GBS and the TASSEL GBS pipeline without modification of the original methodology using the ApeKI restriction enzyme and multiplexing at an equivalent of 96 samples per Illumina HiSeq 2000 lane. We obtained hundreds of SNP markers which were then used to construct a genetic linkage map and identify quantitative trait loci (QTL) for BD and CR. PMID:26430886

  18. Genotyping by Sequencing for SNP-Based Linkage Map Construction and QTL Analysis of Chilling Requirement and Bloom Date in Peach [Prunus persica (L.) Batsch

    PubMed Central

    Bielenberg, Douglas Gary; Rauh, Bradley; Fan, Shenghua; Gasic, Ksenija; Abbott, Albert Glenn; Reighard, Gregory Lynn; Okie, William R.; Wells, Christina Elizabeth

    2015-01-01

    Low-cost, high throughput genotyping methods are crucial to marker discovery and marker-assisted breeding efforts, but have not been available for many ‘specialty crops’ such as fruit and nut trees. Here we apply the Genotyping-By-Sequencing (GBS) method developed for cereals to the discovery of single nucleotide polymorphisms (SNPs) in a peach F2 mapping population. Peach is a genetic and genomic model within the Rosaceae and will provide a template for the use of this method with other members of this family. Our F2 mapping population of 57 genotypes segregates for bloom time (BD) and chilling requirement (CR) and we have extensively phenotyped this population. The population derives from a selfed F1 progeny of a cross between ‘Hakuho’ (high CR) and ‘UFGold’ (low CR). We were able to successfully employ GBS and the TASSEL GBS pipeline without modification of the original methodology using the ApeKI restriction enzyme and multiplexing at an equivalent of 96 samples per Illumina HiSeq 2000 lane. We obtained hundreds of SNP markers which were then used to construct a genetic linkage map and identify quantitative trait loci (QTL) for BD and CR. PMID:26430886

  19. SNP-revealed genetic diversity in wild emmer wheat correlates with ecological factors

    PubMed Central

    2013-01-01

    Background Patterns of genetic diversity between and within natural plant populations and their driving forces are of great interest in evolutionary biology. However, few studies have been performed on the genetic structure and population divergence in wild emmer wheat using a large number of EST-related single nucleotide polymorphism (SNP) markers. Results In the present study, twenty-five natural wild emmer wheat populations representing a wide range of ecological conditions in Israel and Turkey were used. Genetic diversity and genetic structure were investigated using over 1,000 SNP markers. A moderate level of genetic diversity was detected due to the biallelic property of SNP markers. Clustering based on Bayesian model showed that grouping pattern is related to the geographical distribution of the wild emmer wheat. However, genetic differentiation between populations was not necessarily dependent on the geographical distances. A total of 33 outlier loci under positive selection were identified using a FST-outlier method. Significant correlations between loci and ecogeographical factors were observed. Conclusions Natural selection appears to play a major role in generating adaptive structures in wild emmer wheat. SNP markers are appropriate for detecting selectively-channeled adaptive genetic diversity in natural populations of wild emmer wheat. This adaptive genetic diversity is significantly associated with ecological factors. PMID:23937410

  20. Association of Agronomic Traits with SNP Markers in Durum Wheat (Triticum turgidum L. durum (Desf.))

    PubMed Central

    Hu, Xin; Ren, Jing; Ren, Xifeng; Huang, Sisi; Sabiel, Salih A. I.; Luo, Mingcheng; Nevo, Eviatar; Fu, Chunjie; Peng, Junhua; Sun, Dongfa

    2015-01-01

    Association mapping is a powerful approach to detect associations between traits of interest and genetic markers based on linkage disequilibrium (LD) in molecular plant breeding. In this study, 150 accessions of worldwide originated durum wheat germplasm (Triticum turgidum spp. durum) were genotyped using 1,366 SNP markers. The extent of LD on each chromosome was evaluated. Association of single nucleotide polymorphisms (SNP) markers with ten agronomic traits measured in four consecutive years was analyzed under a mix linear model (MLM). Two hundred and one significant association pairs were detected in the four years. Several markers were associated with one trait, and also some markers were associated with multiple traits. Some of the associated markers were in agreement with previous quantitative trait loci (QTL) analyses. The function and homology analyses of the corresponding ESTs of some SNP markers could explain many of the associations for plant height, length of main spike, number of spikelets on main spike, grain number per plant, and 1000-grain weight, etc. The SNP associations for the observed traits are generally clustered in specific chromosome regions of the wheat genome, mainly in 2A, 5A, 6A, 7A, 1B, and 6B chromosomes. This study demonstrates that association mapping can complement and enhance previous QTL analyses and provide additional information for marker-assisted selection. PMID:26110423

  1. A SNP resource for Douglas-fir: de novo transcriptome assembly and SNP detection and validation

    PubMed Central

    2013-01-01

    Background Douglas-fir (Pseudotsuga menziesii), one of the most economically and ecologically important tree species in the world, also has one of the largest tree breeding programs. Although the coastal and interior varieties of Douglas-fir (vars. menziesii and glauca) are native to North America, the coastal variety is also widely planted for timber production in Europe, New Zealand, Australia, and Chile. Our main goal was to develop a SNP resource large enough to facilitate genomic selection in Douglas-fir breeding programs. To accomplish this, we developed a 454-based reference transcriptome for coastal Douglas-fir, annotated and evaluated the quality of the reference, identified putative SNPs, and then validated a sample of those SNPs using the Illumina Infinium genotyping platform. Results We assembled a reference transcriptome consisting of 25,002 isogroups (unique gene models) and 102,623 singletons from 2.76 million 454 and Sanger cDNA sequences from coastal Douglas-fir. We identified 278,979 unique SNPs by mapping the 454 and Sanger sequences to the reference, and by mapping four datasets of Illumina cDNA sequences from multiple seed sources, genotypes, and tissues. The Illumina datasets represented coastal Douglas-fir (64.00 and 13.41 million reads), interior Douglas-fir (80.45 million reads), and a Yakima population similar to interior Douglas-fir (8.99 million reads). We assayed 8067 SNPs on 260 trees using an Illumina Infinium SNP genotyping array. Of these SNPs, 5847 (72.5%) were called successfully and were polymorphic. Conclusions Based on our validation efficiency, our SNP database may contain as many as ~200,000 true SNPs, and as many as ~69,000 SNPs that could be genotyped at ~20,000 gene loci using an Infinium II array—more SNPs than are needed to use genomic selection in tree breeding programs. Ultimately, these genomic resources will enhance Douglas-fir breeding and allow us to better understand landscape-scale patterns of genetic variation

  2. Exhaustive Genome-Wide Search for SNP-SNP Interactions Across 10 Human Diseases.

    PubMed

    Murk, William; DeWan, Andrew T

    2016-01-01

    The identification of statistical SNP-SNP interactions may help explain the genetic etiology of many human diseases, but exhaustive genome-wide searches for these interactions have been difficult, due to a lack of power in most datasets. We aimed to use data from the Resource for Genetic Epidemiology Research on Adult Health and Aging (GERA) study to search for SNP-SNP interactions associated with 10 common diseases. FastEpistasis and BOOST were used to evaluate all pairwise interactions among approximately N = 300,000 single nucleotide polymorphisms (SNPs) with minor allele frequency (MAF) ≥ 0.15, for the dichotomous outcomes of allergic rhinitis, asthma, cardiac disease, depression, dermatophytosis, type 2 diabetes, dyslipidemia, hemorrhoids, hypertensive disease, and osteoarthritis. A total of N = 45,171 subjects were included after quality control steps were applied. These data were divided into discovery and replication subsets; the discovery subset had > 80% power, under selected models, to detect genome-wide significant interactions (P < 10(-12)). Interactions were also evaluated for enrichment in particular SNP features, including functionality, prior disease relevancy, and marginal effects. No interaction in any disease was significant in both the discovery and replication subsets. Enrichment analysis suggested that, for some outcomes, interactions involving SNPs with marginal effects were more likely to be nominally replicated, compared to interactions without marginal effects. If SNP-SNP interactions play a role in the etiology of the studied conditions, they likely have weak effect sizes, involve lower-frequency variants, and/or involve complex models of interaction that are not captured well by the methods that were utilized. PMID:27185397

  3. Exhaustive Genome-Wide Search for SNP-SNP Interactions Across 10 Human Diseases

    PubMed Central

    Murk, William; DeWan, Andrew T.

    2016-01-01

    The identification of statistical SNP-SNP interactions may help explain the genetic etiology of many human diseases, but exhaustive genome-wide searches for these interactions have been difficult, due to a lack of power in most datasets. We aimed to use data from the Resource for Genetic Epidemiology Research on Adult Health and Aging (GERA) study to search for SNP-SNP interactions associated with 10 common diseases. FastEpistasis and BOOST were used to evaluate all pairwise interactions among approximately N = 300,000 single nucleotide polymorphisms (SNPs) with minor allele frequency (MAF) ≥ 0.15, for the dichotomous outcomes of allergic rhinitis, asthma, cardiac disease, depression, dermatophytosis, type 2 diabetes, dyslipidemia, hemorrhoids, hypertensive disease, and osteoarthritis. A total of N = 45,171 subjects were included after quality control steps were applied. These data were divided into discovery and replication subsets; the discovery subset had > 80% power, under selected models, to detect genome-wide significant interactions (P < 10−12). Interactions were also evaluated for enrichment in particular SNP features, including functionality, prior disease relevancy, and marginal effects. No interaction in any disease was significant in both the discovery and replication subsets. Enrichment analysis suggested that, for some outcomes, interactions involving SNPs with marginal effects were more likely to be nominally replicated, compared to interactions without marginal effects. If SNP-SNP interactions play a role in the etiology of the studied conditions, they likely have weak effect sizes, involve lower-frequency variants, and/or involve complex models of interaction that are not captured well by the methods that were utilized. PMID:27185397

  4. High volume molecular genetic identification of single nucleotide polymorphisms using Genetic Bit Analysis Application to human genetic diagnosis

    SciTech Connect

    Boyce-Jacino, M.T.; Reynolds, J.; Nikiforov, T.

    1994-09-01

    The most common type of genetic disease-associated mutation is the single nucleotide polymorphism (SNP). Because most genetic diseases can be caused by multiple SNPs in the same gene, effective routine diagnosis of complex genetic diseases is dependent on a simple and reliable method of interrogating SNP sites. Molecular Tool`s solid phase assay capable of direct genotyping (single base sequencing) of SNP sites, Genetic Bit Analysis (GBA), involves hybridization-capture of a single-stranded PCR product to a sequence-specific, microtiter plate-bound oligonucleotide primer. The captured PCR product then acts as template for single-base extension of the capture primer across the polymorphic site, enabling direct determination of the base composition of the polymorphism through a simple colormetric assay. Genotyping in a high volume, semi-automated, processing system with a current capacity of 100 SNP interrogations per technician per day enables the screening of candidate mutations rapidly and cost-effectively, critically important to comprehensive genetic diagnosis. Using this gel-free technology, we have developed prototype diagnostic tests for CFTR and ApoE polymorphisms which enable direct sequencing of the polymorphic base at each site of interest. Routine clinical diagnosis of genetically complex diseases such as cystic fibrosis is dependent on this combination of robust biochemistry and simple format. Additionally, the ability to transfer the format and biochemistry to any disease gene of interest enables the broad application of this technology to clinical diagnostics, especially for genetically complex diseases.

  5. Lineage and genogroup-defining single nucleotide polymorphisms of Escherichia coli 0157:H7

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Escherichia coli O157:H7 is a zoonotic human pathogen for which cattle are an important reservoir host. Using both previously published and new sequencing data, a 48-locus single nucleotide polymorphism (SNP) based typing panel was developed that redundantly identified eleven genogroups that span ...

  6. Using 90,113 single nucleotide polymorphisms in genomic evaluation of dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accuracy of genomic evaluation is expected to increase when more markers are used because of better tracking of causative genetic variants. However, Illumina BovineHD genotypes based on 777,962 single nucleotide polymorphisms (SNP) have not been used for US genomic evaluation because the small relia...

  7. Identification of SNP Haplotypes and Prospects of Association Mapping in Watermelon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon is the fifth most economically important vegetable crop cultivated world-wide. Implementing Single Nucleotide Polymorphism (SNP) marker technology in watermelon breeding and germplasm evaluation programs holds a key to improve horticulturally important traits. Next-generation sequencing...

  8. SNP discovery through de novo deep sequencing using the next generation of DNA sequencers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The production of high volumes of DNA sequence data using new technologies has permitted more efficient identification of single nucleotide polymorphisms in vertebrate genomes. This chapter presented practical methodology for production and analysis of DNA sequence data for SNP discovery....

  9. Exploration of SNP variants affecting hair colour prediction in Europeans.

    PubMed

    Söchtig, Jens; Phillips, Chris; Maroñas, Olalla; Gómez-Tato, Antonio; Cruz, Raquel; Alvarez-Dios, Jose; de Cal, María-Ángeles Casares; Ruiz, Yarimar; Reich, Kristian; Fondevila, Manuel; Carracedo, Ángel; Lareu, María V

    2015-09-01

    DNA profiling is a key tool for forensic analysis; however, current methods identify a suspect either by direct comparison or from DNA database searches. In cases with unidentified suspects, prediction of visible physical traits e.g. pigmentation or hair distribution of the DNA donors can provide important probative information. This study aimed to explore single nucleotide polymorphism (SNP) variants for their effect on hair colour prediction. A discovery panel of 63 SNPs consisting of already established hair colour markers from the HIrisPlex hair colour phenotyping assay as well as additional markers for which associations to human pigmentation traits were previously identified was used to develop multiplex assays based on SNaPshot single-base extension technology. A genotyping study was performed on a range of European populations (n = 605). Hair colour phenotyping was accomplished by matching donor's hair to a graded colour category system of reference shades and photography. Since multiple SNPs in combination contribute in varying degrees to hair colour predictability in Europeans, we aimed to compile a compact marker set that could provide a reliable hair colour inference from the fewest SNPs. The predictive approach developed uses a naïve Bayes classifier to provide hair colour assignment probabilities for the SNP profiles of the key SNPs and was embedded into the Snipper online SNP classifier ( http://mathgene.usc.es/snipper/ ). Results indicate that red, blond, brown and black hair colours are predictable with informative probabilities in a high proportion of cases. Our study resulted in the identification of 12 most strongly associated SNPs to hair pigmentation variation in six genes. PMID:26162598

  10. Characterization of the Cattle HapMap Population using the Illumina Bovine-50K SNP Chip

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A Bovine 50K Illumina™ iSelect SNP chip (51,386 polymorphic SNP markers) was designed using a combination of publicly available SNPs along with highly informative novel SNPs discovered using a reduced representation and next-generation sequencing technology strategy. A total of 576 animals (426 mal...

  11. Development and Applications of a Bovine 50,000 SNP Chip

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To develop an Illumina iSelect high density single nucleotide polymorphism (SNP) assay for cattle, the collaborative iBMC (Illumina, USDA ARS Beltsville, University of Missouri, USDA ARS Clay Center) Consortium first performed a de novo SNP discovery project in which genomic reduced representation l...

  12. Multiple SNP Set Analysis for Genome-Wide Association Studies Through Bayesian Latent Variable Selection.

    PubMed

    Lu, Zhao-Hua; Zhu, Hongtu; Knickmeyer, Rebecca C; Sullivan, Patrick F; Williams, Stephanie N; Zou, Fei

    2015-12-01

    The power of genome-wide association studies (GWAS) for mapping complex traits with single-SNP analysis (where SNP is single-nucleotide polymorphism) may be undermined by modest SNP effect sizes, unobserved causal SNPs, correlation among adjacent SNPs, and SNP-SNP interactions. Alternative approaches for testing the association between a single SNP set and individual phenotypes have been shown to be promising for improving the power of GWAS. We propose a Bayesian latent variable selection (BLVS) method to simultaneously model the joint association mapping between a large number of SNP sets and complex traits. Compared with single SNP set analysis, such joint association mapping not only accounts for the correlation among SNP sets but also is capable of detecting causal SNP sets that are marginally uncorrelated with traits. The spike-and-slab prior assigned to the effects of SNP sets can greatly reduce the dimension of effective SNP sets, while speeding up computation. An efficient Markov chain Monte Carlo algorithm is developed. Simulations demonstrate that BLVS outperforms several competing variable selection methods in some important scenarios. PMID:26515609

  13. Genetic Profiling by Single-Nucleotide Polymorphism-Based Array Analysis Defines Three Distinct Subtypes of Orbital Meningioma

    PubMed Central

    Ho, Cheng-Ying; Mosier, Stacy; Safneck, Janice; Salomao, Diva R.; Miller, Neil R.; Eberhart, Charles G.; Gocke, Christopher D.; Batista, Denise A. S.; Rodriguez, Fausto J.

    2015-01-01

    Orbital meningiomas can be classified as primary optic nerve sheath (ON) meningiomas, primary intraorbital ectopic (Ob) meningiomas and spheno-orbital (Sph-Ob) meningiomas based on anatomic site. Single-nucleotide polymorphism (SNP)-based array analysis with the Illumina 300K platform was performed on formalin-fixed, paraffin-embedded tissue from 19 orbital meningiomas (5 ON, 4 Ob and 10 Sph-Ob meningiomas). Tumors were World Health Organization (WHO) grade I except for two grade II meningiomas, and one was NF2-associated. We found genomic alterations in 68% (13 of 19) of orbital meningiomas. Sph-Ob tumors frequently exhibited monosomy 22/22q loss (70%; 7/10) and deletion of chromosome 1p, 6q and 19p (50% each; 5/10). Among genetic alterations, loss of chromosome 1p and 6q were more frequent in clinically progressive tumors. Chromosome 22q loss also was detected in the majority of Ob meningiomas (75%; 3/4) but was infrequent in ON meningiomas (20%; 1/5). In general, Ob tumors had fewer chromosome alterations than Sph-Ob and ON tumors. Unlike Sph-Ob meningiomas, most of the Ob and ON meningiomas did not progress even after incomplete excision, although follow-up was limited in some cases. Our study suggests that ON, Ob and Sph-Ob meningiomas are three molecularly distinct entities. Our results also suggest that molecular subclassification may have prognostic implications. PMID:24773246

  14. Differential diagnosis of Brucella abortus by real-time PCR based on a single-nucleotide polymorphisms

    PubMed Central

    KIM, Ji-Yeon; KANG, Sung-Il; LEE, Jin Ju; LEE, Kichan; SUNG, So-Ra; ERDENEBAATAAR, Janchivdorj; VANAABAATAR, Batbaatar; JUNG, Suk Chan; PARK, Yong Ho; YOO, Han-Sang; HER, Moon

    2015-01-01

    To diagnose brucellosis effectively, many genus- and species-specific detection methods based on PCR have been developed. With conventional PCR assays, real-time PCR techniques have been developed as rapid diagnostic tools. Among them, real-time PCR using hybridization probe (hybprobe) has been recommended for bacteria with high DNA homology among species, with which it is possible to make an accurate diagnosis by means of an amplification curve and melting peak analysis. A hybprobe for B. abortus was designed from a specific single-nucleotide polymorphism (SNP) on the fbaA gene. This probe only showed specific amplification of B. abortus from approximately the 14th cycle, given a melting peak at 69°C. The sensitivity of real-time PCR was revealed to be 20 fg/µl by 10-fold DNA dilution, and the detection limit was 4 CFU in clinical samples. This real-time PCR showed greater sensitivity than that of conventional PCR and previous real-time PCR based on Taqman probe. Therefore, this new real-time PCR assay could be helpful for differentiating B. abortus infection with rapidity and accuracy. PMID:26666176

  15. Differential diagnosis of Brucella abortus by real-time PCR based on a single-nucleotide polymorphisms.

    PubMed

    Kim, Ji-Yeon; Kang, Sung-Il; Lee, Jin Ju; Lee, Kichan; Sung, So-Ra; Erdenebaataar, Janchivdorj; Vanaabaatar, Batbaatar; Jung, Suk Chan; Park, Yong Ho; Yoo, Han-Sang; Her, Moon

    2016-05-01

    To diagnose brucellosis effectively, many genus- and species-specific detection methods based on PCR have been developed. With conventional PCR assays, real-time PCR techniques have been developed as rapid diagnostic tools. Among them, real-time PCR using hybridization probe (hybprobe) has been recommended for bacteria with high DNA homology among species, with which it is possible to make an accurate diagnosis by means of an amplification curve and melting peak analysis. A hybprobe for B. abortus was designed from a specific single-nucleotide polymorphism (SNP) on the fbaA gene. This probe only showed specific amplification of B. abortus from approximately the 14th cycle, given a melting peak at 69°C. The sensitivity of real-time PCR was revealed to be 20 fg/µl by 10-fold DNA dilution, and the detection limit was 4 CFU in clinical samples. This real-time PCR showed greater sensitivity than that of conventional PCR and previous real-time PCR based on Taqman probe. Therefore, this new real-time PCR assay could be helpful for differentiating B. abortus infection with rapidity and accuracy. PMID:26666176

  16. Analysis of genetic diversity using SNP markers in oat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A large-scale single nucleotide polymorphism (SNP) discovery was carried out in cultivated oat using Roche 454 sequencing methods. DNA sequences were generated from cDNAs originating from a panel of 20 diverse oat cultivars, and from Diversity Array Technology (DArT) genomic complexity reductions fr...

  17. Inter-laboratory evaluation of SNP-based forensic identification by massively parallel sequencing using the Ion PGM™.

    PubMed

    Eduardoff, M; Santos, C; de la Puente, M; Gross, T E; Fondevila, M; Strobl, C; Sobrino, B; Ballard, D; Schneider, P M; Carracedo, Á; Lareu, M V; Parson, W; Phillips, C

    2015-07-01

    Next generation sequencing (NGS) offers the opportunity to analyse forensic DNA samples and obtain massively parallel coverage of targeted short sequences with the variants they carry. We evaluated the levels of sequence coverage, genotyping precision, sensitivity and mixed DNA patterns of a prototype version of the first commercial forensic NGS kit: the HID-Ion AmpliSeq™ Identity Panel with 169-markers designed for the Ion PGM™ system. Evaluations were made between three laboratories following closely matched Ion PGM™ protocols and a simple validation framework of shared DNA controls. The sequence coverage obtained was extensive for the bulk of SNPs targeted by the HID-Ion AmpliSeq™ Identity Panel. Sensitivity studies showed 90-95% of SNP genotypes could be obtained from 25 to 100pg of input DNA. Genotyping concordance tests included Coriell cell-line control DNA analyses checked against whole-genome sequencing data from 1000 Genomes and Complete Genomics, indicating a very high concordance rate of 99.8%. Discordant genotypes detected in rs1979255, rs1004357, rs938283, rs2032597 and rs2399332 indicate these loci should be excluded from the panel. Therefore, the HID-Ion AmpliSeq™ Identity Panel and Ion PGM™ system provide a sensitive and accurate forensic SNP genotyping assay. However, low-level DNA produced much more varied sequence coverage and in forensic use the Ion PGM™ system will require careful calibration of the total samples loaded per chip to preserve the genotyping reliability seen in routine forensic DNA. Furthermore, assessments of mixed DNA indicate the user's control of sequence analysis parameter settings is necessary to ensure mixtures are detected robustly. Given the sensitivity of Ion PGM™, this aspect of forensic genotyping requires further optimisation before massively parallel sequencing is applied to routine casework. PMID:25955683

  18. SNP panels/Imputation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Participants from thirteen countries discussed services that Interbull can perform or recommendations that Interbull can make to promote harmonization and assist member countries in improving their genomic evaluations in regard to SNP panels and imputation. The panel recommended: A mechanism to shar...

  19. SNP Markers and Their Impact on Plant Breeding

    PubMed Central

    Mammadov, Jafar; Aggarwal, Rajat; Buyyarapu, Ramesh; Kumpatla, Siva

    2012-01-01

    The use of molecular markers has revolutionized the pace and precision of plant genetic analysis which in turn facilitated the implementation of molecular breeding of crops. The last three decades have seen tremendous advances in the evolution of marker systems and the respective detection platforms. Markers based on single nucleotide polymorphisms (SNPs) have rapidly gained the center stage of molecular genetics during the recent years due to their abundance in the genomes and their amenability for high-throughput detection formats and platforms. Computational approaches dominate SNP discovery methods due to the ever-increasing sequence information in public databases; however, complex genomes pose special challenges in the identification of informative SNPs warranting alternative strategies in those crops. Many genotyping platforms and chemistries have become available making the use of SNPs even more attractive and efficient. This paper provides a review of historical and current efforts in the development, validation, and application of SNP markers in QTL/gene discovery and plant breeding by discussing key experimental strategies and cases exemplifying their impact. PMID:23316221

  20. A 48 SNP set for grapevine cultivar identification

    PubMed Central

    2011-01-01

    Background Rapid and consistent genotyping is an important requirement for cultivar identification in many crop species. Among them grapevine cultivars have been the subject of multiple studies given the large number of synonyms and homonyms generated during many centuries of vegetative multiplication and exchange. Simple sequence repeat (SSR) markers have been preferred until now because of their high level of polymorphism, their codominant nature and their high profile repeatability. However, the rapid application of partial or complete genome sequencing approaches is identifying thousands of single nucleotide polymorphisms (SNP) that can be very useful for such purposes. Although SNP markers are bi-allelic, and therefore not as polymorphic as microsatellites, the high number of loci that can be multiplexed and the possibilities of automation as well as their highly repeatable results under any analytical procedure make them the future markers of choice for any type of genetic identification. Results We analyzed over 300 SNP in the genome of grapevine using a re-sequencing strategy in a selection of 11 genotypes. Among the identified polymorphisms, we selected 48 SNP spread across all grapevine chromosomes with allele frequencies balanced enough as to provide sufficient information content for genetic identification in grapevine allowing for good genotyping success rate. Marker stability was tested in repeated analyses of a selected group of cultivars obtained worldwide to demonstrate their usefulness in genetic identification. Conclusions We have selected a set of 48 stable SNP markers with a high discrimination power and a uniform genome distribution (2-3 markers/chromosome), which is proposed as a standard set for grapevine (Vitis vinifera L.) genotyping. Any previous problems derived from microsatellite allele confusion between labs or the need to run reference cultivars to identify allele sizes disappear using this type of marker. Furthermore, because SNP

  1. High-throughput genotyping of single nucleotide polymorphisms with rolling circle amplification

    PubMed Central

    Faruqi, A Fawad; Hosono, Seiyu; Driscoll, Mark D; Dean, Frank B; Alsmadi, Osama; Bandaru, Rajanikanta; Kumar, Gyanendra; Grimwade, Brian; Zong, Qiuling; Sun, Zhenyu; Du, Yuefen; Kingsmore, Stephen; Knott, Tim; Lasken, Roger S

    2001-01-01

    Background Single nucleotide polymorphisms (SNPs) are the foundation of powerful complex trait and pharmacogenomic analyses. The availability of large SNP databases, however, has emphasized a need for inexpensive SNP genotyping methods of commensurate simplicity, robustness, and scalability. We describe a solution-based, microtiter plate method for SNP genotyping of human genomic DNA. The method is based upon allele discrimination by ligation of open circle probes followed by rolling circle amplification of the signal using fluorescent primers. Only the probe with a 3' base complementary to the SNP is circularized by ligation. Results SNP scoring by ligation was optimized to a 100,000 fold discrimination against probe mismatched to the SNP. The assay was used to genotype 10 SNPs from a set of 192 genomic DNA samples in a high-throughput format. Assay directly from genomic DNA eliminates the need to preamplify the target as done for many other genotyping methods. The sensitivity of the assay was demonstrated by genotyping from 1 ng of genomic DNA. We demonstrate that the assay can detect a single molecule of the circularized probe. Conclusions Compatibility with homogeneous formats and the ability to assay small amounts of genomic DNA meets the exacting requirements of automated, high-throughput SNP scoring. PMID:11511324

  2. UV-visible sensors based on polymorphous silicon

    NASA Astrophysics Data System (ADS)

    Guedj, Cyril S.; Cabarrocas, Pere R. i.; Massoni, Nicolas; Moussy, Norbert; Morel, Damien; Tchakarov, Svetoslav; Bonnassieux, Yvan

    2003-09-01

    UV-based imaging systems can be used for low-altitude rockets detection or biological agents identification (for instance weapons containing ANTHRAX). Compared to conventional CCD technology, CMOS-based active pixel sensors provide several advantages, including excellent electro-optical performances, high integration, low voltage operation, low power consumption, low cost, long lifetime, and robustness against environment. The monolithic integration of UV, visible and infrared detectors on the same uncooled CMOS smart system would therefore represent a major advance in the combat field, for characterization and representation of targets and backgrounds. In this approach, we have recently developped a novel technology using polymorphous silicon. This new material, fully compatible with above-IC silicon technology, is made of nanometric size ordered domains embedded in an amorphous matrix. The typical quantum efficiency of detectors made of this nano-material reach up to 80 % at 550 nm and 30 % in the UV range, depending of the design and the growth parameters. Furthermore, a record dark current of 20 pA/cm2 at -3 V has been reached. In addition, this new generation of sensors is significantly faster and more stable than their amorphous silicon counterparts. In this paper, we will present the relationship between the sensor technology and the overall performances.

  3. Association between vitamin D receptor gene polymorphisms and chronic periodontitis among Libyans

    PubMed Central

    El Jilani, Mouna M.; Mohamed, Abdenaser A.; Zeglam, Hamza Ben; Alhudiri, Inas M.; Ramadan, Ahmad M.; Saleh, Saleh S.; Elkabir, Mohamed; Amer, Ibrahim Ben; Ashammakhi, Nureddin; Enattah, Nabil S.

    2015-01-01

    Background Chronic periodontitis (CP) is a common oral disease characterized by inflammation in the supporting tissue of the teeth ‘the periodontium’, periodontal attachment loss, and alveolar bone loss. The disease has a microbial etiology; however, recent findings suggest that the genetic factors, such as vitamin D receptor (VDR) gene polymorphisms, have also been included. Aim Investigation of the relationship between VDR gene polymorphisms and CP among Libyans. Materials and methods In this study, we examined 196 unrelated Libyans between the ages of 25 and 65 years, including 99 patients and 97 controls. An oral examination based on Ramfjord Index was performed at different dental clinics in Tripoli and information were collected using a self-reported questionnaire. DNA was extracted from buccal swabs; the VDR ApaI, BsmI, and FokI polymorphisms were genotyped using polymerase chain reaction and were sequenced using Sanger Method. Results A significant difference in the newly detected ApaI SNP C/T rs#731236 was found (p=0.022), whereas no significant differences were found in ApaI SNP G/T rs#7975232, BsmI SNP A/G rs#1544410, and FokI SNP A/G rs#2228570 between patients and controls (p=0.939, 0.466, 0.239), respectively. Conclusion VDR ApaI SNP C/T rs#731236 may be related to the risk of CP in the Libyan population. PMID:25795245

  4. Detection of Fusarium oxysporum f. sp. vasinfectum race 3 by single-base extension method and allele-specific polymerase chain reaction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We developed allele specific (AS) SNP primers for rapid detection of Fusarium oxysporum f.sp vasinfectum (FOV) race 3. FOV_BT_SNP_R3 and FOV_BT_AS_R3 primers were designed based on single nucleotide polymorphisms of partial sequence alignment of the ß-tubulin (BT) gene from several FOV races. These ...

  5. The genetics of alcohol dependence: Twin and SNP-based heritability, and genome-wide association study based on AUDIT scores.

    PubMed

    Mbarek, Hamdi; Milaneschi, Yuri; Fedko, Iryna O; Hottenga, Jouke-Jan; de Moor, Marleen H M; Jansen, Rick; Gelernter, Joel; Sherva, Richard; Willemsen, Gonneke; Boomsma, Dorret I; Penninx, Brenda W; Vink, Jacqueline M

    2015-12-01

    Alcohol dependence (AD) is among the most common and costly public health problems contributing to morbidity and mortality throughout the world. In this study, we investigate the genetic basis of AD in a Dutch population using data from the Netherlands Twin Register (NTR) and the Netherlands Study of Depression and Anxiety (NESDA). The presence of AD was ascertained via the Alcohol Use Disorders Identification Test (AUDIT) applying cut-offs with good specificity and sensitivity in identifying those at risk for AD. Twin-based heritability of AD-AUDIT was estimated using structural equation modeling of data in 7,694 MZ and DZ twin pairs. Variance in AD-AUDIT explained by all SNPs was estimated with genome-wide complex trait analysis (GCTA). A genome-wide association study (GWAS) was performed in 7,842 subjects. GWAS SNP effect concordance analysis was performed between our GWAS and a recent AD GWAS using DSM-IV diagnosis. The twin-based heritability of AD-AUDIT was estimated at 60% (55-69%). GCTA showed that common SNPs jointly capture 33% (SE = 0.12, P = 0.002) of this heritability. In the GWAS, the top hits were positioned within four regions (4q31.1, 2p16.1, 6q25.1, 7p14.1) with the strongest association detected for rs55768019 (P = 7.58 × 10(-7) ). This first GWAS of AD using the AUDIT measure found results consistent with previous genetic studies using DSM diagnosis: concordance in heritability estimates and direction of SNPs effect and overlap with top hits from previous GWAS. Thus, the use of appropriate questionnaires may represent cost-effective strategies to phenotype samples in large-scale biobanks or other population-based datasets. PMID:26365420

  6. Systems Genetic Validation of the SNP-Metabolite Association in Rice Via Metabolite-Pathway-Based Phenome-Wide Association Scans

    PubMed Central

    Lu, Yaping; Liu, Yemao; Niu, Xiaohui; Yang, Qingyong; Hu, Xuehai; Zhang, Hong-Yu; Xia, Jingbo

    2015-01-01

    In the post-GWAS (Genome-Wide Association Scan) era, the interpretation of GWAS results is crucial to screen for highly relevant phenotype-genotype association pairs. Based on the single genotype-phenotype association test and a pathway enrichment analysis, we propose a Metabolite-pathway-based Phenome-Wide Association Scan (M-PheWAS) to analyze the key metabolite-SNP pairs in rice and determine the regulatory relationship by assessing similarities in the changes of enzymes and downstream products in a pathway. Two SNPs, sf0315305925 and sf0315308337, were selected using this approach, and their molecular function and regulatory relationship with Enzyme EC:5.5.1.6 and with flavonoids, a significant downstream regulatory metabolite product, were demonstrated. Moreover, a total of 105 crucial SNPs were screened using M-PheWAS, which may be important for metabolite associations. PMID:26640468

  7. Characterization of Foodborne Outbreaks of Salmonella enterica Serovar Enteritidis with Whole-Genome Sequencing Single Nucleotide Polymorphism-Based Analysis for Surveillance and Outbreak Detection

    PubMed Central

    Lappi, Victoria; Wolfgang, William J.; Lapierre, Pascal; Palumbo, Michael J.; Medus, Carlota; Boxrud, David

    2015-01-01

    Salmonella enterica serovar Enteritidis is a significant cause of gastrointestinal illness in the United States; however, current molecular subtyping methods lack resolution for this highly clonal serovar. Advances in next-generation sequencing technologies have made it possible to examine whole-genome sequencing (WGS) as a potential molecular subtyping tool for outbreak detection and source trace back. Here, we conducted a retrospective analysis of S. Enteritidis isolates from seven epidemiologically confirmed foodborne outbreaks and sporadic isolates (not epidemiologically linked) to determine the utility of WGS to identify outbreaks. A collection of 55 epidemiologically characterized clinical and environmental S. Enteritidis isolates were sequenced. Single nucleotide polymorphism (SNP)-based cluster analysis of the S. Enteritidis genomes revealed well supported clades, with less than four-SNP pairwise diversity, that were concordant with epidemiologically defined outbreaks. Sporadic isolates were an average of 42.5 SNPs distant from the outbreak clusters. Isolates collected from the same patient over several weeks differed by only two SNPs. Our findings show that WGS provided greater resolution between outbreak, sporadic, and suspect isolates than the current gold standard subtyping method, pulsed-field gel electrophoresis (PFGE). Furthermore, results could be obtained in a time frame suitable for surveillance activities, supporting the use of WGS as an outbreak detection and characterization method for S. Enteritidis. PMID:26269623

  8. A novel lateral flow assay based on GoldMag nanoparticles and its clinical applications for genotyping of MTHFR C677T polymorphisms.

    PubMed

    Hui, Wenli; Zhang, Sinong; Zhang, Chao; Wan, Yinsheng; Zhu, Juanli; Zhao, Gang; Wu, Songdi; Xi, Dujuan; Zhang, Qinlu; Li, Ningning; Cui, Yali

    2016-02-14

    Current techniques for single nucleotide polymorphism (SNP) detection require tedious experimental procedures and expensive and sophisticated instruments. In this study, a visual genotyping method has been successfully established via combining ARMS-PCR with gold magnetic nanoparticle (GoldMag)-based lateral flow assay (LFA) and applied to the genotyping of methylenetetrahydrofolate reductase (MTHFR) C677T. C677T substitution of the gene MTHFR leads to an increased risk of diseases. The genotyping result is easily achievable by visual observation within 5 minutes after loading of the PCR products onto the LFA device. The system is able to accurately assess a broad detection range of initial starting genomic DNA amounts from 5 ng to 1200 ng per test sample. The limit of detection reaches 5 ng. Furthermore, our PCR-LFA system was applied to clinical trials for screening 1721 individuals for the C677T genotypes. The concordance rate of the genotyping results detected by PCR-LFA was up to 99.6% when compared with the sequencing results. Collectively, our PCR-LFA has been proven to be rapid, accurate, sensitive, and inexpensive. This new method is highly applicable for C677T SNP screening in laboratories and clinical practices. More promisingly, it could also be extended to the detection of SNPs of other genes. PMID:26804455

  9. Characterization of Foodborne Outbreaks of Salmonella enterica Serovar Enteritidis with Whole-Genome Sequencing Single Nucleotide Polymorphism-Based Analysis for Surveillance and Outbreak Detection.

    PubMed

    Taylor, Angela J; Lappi, Victoria; Wolfgang, William J; Lapierre, Pascal; Palumbo, Michael J; Medus, Carlota; Boxrud, David

    2015-10-01

    Salmonella enterica serovar Enteritidis is a significant cause of gastrointestinal illness in the United States; however, current molecular subtyping methods lack resolution for this highly clonal serovar. Advances in next-generation sequencing technologies have made it possible to examine whole-genome sequencing (WGS) as a potential molecular subtyping tool for outbreak detection and source trace back. Here, we conducted a retrospective analysis of S. Enteritidis isolates from seven epidemiologically confirmed foodborne outbreaks and sporadic isolates (not epidemiologically linked) to determine the utility of WGS to identify outbreaks. A collection of 55 epidemiologically characterized clinical and environmental S. Enteritidis isolates were sequenced. Single nucleotide polymorphism (SNP)-based cluster analysis of the S. Enteritidis genomes revealed well supported clades, with less than four-SNP pairwise diversity, that were concordant with epidemiologically defined outbreaks. Sporadic isolates were an average of 42.5 SNPs distant from the outbreak clusters. Isolates collected from the same patient over several weeks differed by only two SNPs. Our findings show that WGS provided greater resolution between outbreak, sporadic, and suspect isolates than the current gold standard subtyping method, pulsed-field gel electrophoresis (PFGE). Furthermore, results could be obtained in a time frame suitable for surveillance activities, supporting the use of WGS as an outbreak detection and characterization method for S. Enteritidis. PMID:26269623

  10. A novel lateral flow assay based on GoldMag nanoparticles and its clinical applications for genotyping of MTHFR C677T polymorphisms

    NASA Astrophysics Data System (ADS)

    Hui, Wenli; Zhang, Sinong; Zhang, Chao; Wan, Yinsheng; Zhu, Juanli; Zhao, Gang; Wu, Songdi; Xi, Dujuan; Zhang, Qinlu; Li, Ningning; Cui, Yali

    2016-02-01

    Current techniques for single nucleotide polymorphism (SNP) detection require tedious experimental procedures and expensive and sophisticated instruments. In this study, a visual genotyping method has been successfully established via combining ARMS-PCR with gold magnetic nanoparticle (GoldMag)-based lateral flow assay (LFA) and applied to the genotyping of methylenetetrahydrofolate reductase (MTHFR) C677T. C677T substitution of the gene MTHFR leads to an increased risk of diseases. The genotyping result is easily achievable by visual observation within 5 minutes after loading of the PCR products onto the LFA device. The system is able to accurately assess a broad detection range of initial starting genomic DNA amounts from 5 ng to 1200 ng per test sample. The limit of detection reaches 5 ng. Furthermore, our PCR-LFA system was applied to clinical trials for screening 1721 individuals for the C677T genotypes. The concordance rate of the genotyping results detected by PCR-LFA was up to 99.6% when compared with the sequencing results. Collectively, our PCR-LFA has been proven to be rapid, accurate, sensitive, and inexpensive. This new method is highly applicable for C677T SNP screening in laboratories and clinical practices. More promisingly, it could also be extended to the detection of SNPs of other genes.

  11. PCR amplification of SNP loci from crude DNA for large-scale genotyping of oomycetes.

    PubMed

    Hu, Jian; Lyon, Rebecca; Zhou, Yuxin; Lamour, Kurt

    2014-01-01

    Similar to other eukaryotes, single nucleotide polymorphism (SNP) markers are abundant in many oomycete plant pathogen genomes. High resolution DNA melting analysis (HR-DMA) is a cost-effective method for SNP genotyping, but like many SNP marker technologies, is limited by the amount and quality of template DNA. We describe PCR preamplification of Phytophthora and Peronospora SNP loci from crude DNA extracted from a small amount of mycelium and/or infected plant tissue to produce sufficient template to genotype at least 10 000 SNPs. The approach is fast, inexpensive, requires minimal biological material and should be useful for many organisms in a variety of contexts. PMID:24871597

  12. Lack of association between MDM2 promoter SNP309 and clinical outcome in patients with neuroblastoma.

    PubMed

    Rihani, Ali; Van Maerken, Tom; De Wilde, Bram; Zeka, Fjoralba; Laureys, Geneviève; Norga, Koen; Tonini, Gian Paolo; Coco, Simona; Versteeg, Rogier; Noguera, Rosa; Schulte, Johannes H; Eggert, Angelika; Stallings, Raymond L; Speleman, Frank; Vandesompele, Jo

    2014-10-01

    While a polymorphism located within the promoter region of the MDM2 proto-oncogene, SNP309 (T > G), has previously been associated with increased risk and aggressiveness of neuroblastoma and other tumor entities, a protective effect has also been reported in certain other cancers. In this study, we evaluated the association of MDM2 SNP309 with outcome in 496 patients with neuroblastoma and its effect on MDM2 expression. No significant difference in overall or event-free survival was observed among patients with neuroblastoma with or without MDM2 SNP309. The presence of SNP309 does not affect MDM2 expression in neuroblastoma. PMID:24391119

  13. High-density genetic linkage mapping in turbot (Scophthalmus maximus L.) based on SNP markers and major sex- and growth-related regions detection.

    PubMed

    Wang, Weiji; Hu, Yulong; Ma, Yu; Xu, Liyong; Guan, Jiantao; Kong, Jie

    2015-01-01

    This paper describes the development of a high density consensus genetic linkage map of a turbot (Scophthalmus maximus L.) family composed of 149 mapping individuals using Single Nucleotide Polymorphisms (SNP) developed using the restriction-site associated DNA (RAD) sequencing technique with the restriction enzyme, PstI. A total of 6,647 SNPs were assigned to 22 linkage groups, which is equal to the number of chromosome pairs in turbot. For the first time, the average marker interval reached 0.3958 cM, which is equal to approximately 0.1203 Mb of the turbot genome. The observed 99.34% genome coverage indicates that the linkage map was genome-wide. A total of 220 Quantitative Traits Locus (QTLs) associated with two body length traits, two body weight traits in different growth periods and sex determination were detected with an LOD > 5.0 in 12 linkage groups (LGs), which explained the corresponding phenotypic variance (R2), ranging from 14.4-100%. Among them, 175 overlapped with linked SNPs, and the remaining 45 were located in regions between contiguous SNPs. According to the QTLs related to growth trait distribution and the changing of LGs during different growth periods, the growth traits are likely controlled by multi-SNPs distributed on several LGs; the effect of these SNPs changed during different growth periods. Most sex-related QTLs were detected at LG 21 with a linkage span of 70.882 cM. Additionally, a small number of QTLs with high feasibility and a narrow R2 distribution were also observed on LG7 and LG14, suggesting that multi LGs or chromosomes might be involved in sex determination. High homology was recorded between LG21 in Cynoglossus semilaevis and turbot. This high-saturated turbot RAD-Seq linkage map is undoubtedly a promising platform for marker assisted selection (MAS) and flatfish genomics research. PMID:25775256

  14. High-Density Genetic Linkage Mapping in Turbot (Scophthalmus maximus L.) Based on SNP Markers and Major Sex- and Growth-Related Regions Detection

    PubMed Central

    Wang, Weiji; Hu, Yulong; Ma, Yu; Xu, Liyong; Guan, Jiantao; Kong, Jie

    2015-01-01

    This paper describes the development of a high density consensus genetic linkage map of a turbot (Scophthalmus maximus L.) family composed of 149 mapping individuals using Single Nucleotide Polymorphisms (SNP) developed using the restriction-site associated DNA (RAD) sequencing technique with the restriction enzyme, PstI. A total of 6,647 SNPs were assigned to 22 linkage groups, which is equal to the number of chromosome pairs in turbot. For the first time, the average marker interval reached 0.3958 cM, which is equal to approximately 0.1203 Mb of the turbot genome. The observed 99.34% genome coverage indicates that the linkage map was genome-wide. A total of 220 Quantitative Traits Locus (QTLs) associated with two body length traits, two body weight traits in different growth periods and sex determination were detected with an LOD > 5.0 in 12 linkage groups (LGs), which explained the corresponding phenotypic variance (R2), ranging from 14.4–100%. Among them, 175 overlapped with linked SNPs, and the remaining 45 were located in regions between contiguous SNPs. According to the QTLs related to growth trait distribution and the changing of LGs during different growth periods, the growth traits are likely controlled by multi-SNPs distributed on several LGs; the effect of these SNPs changed during different growth periods. Most sex-related QTLs were detected at LG 21 with a linkage span of 70.882 cM. Additionally, a small number of QTLs with high feasibility and a narrow R2 distribution were also observed on LG7 and LG14, suggesting that multi LGs or chromosomes might be involved in sex determination. High homology was recorded between LG21 in Cynoglossus semilaevis and turbot. This high-saturated turbot RAD-Seq linkage map is undoubtedly a promising platform for marker assisted selection (MAS) and flatfish genomics research. PMID:25775256

  15. From Single Nucleotide Polymorphism to Transcriptional Mechanism

    PubMed Central

    Martini, Sebastian; Nair, Viji; Patel, Sanjeevkumar R.; Eichinger, Felix; Nelson, Robert G.; Weil, E. Jennifer; Pezzolesi, Marcus G.; Krolewski, Andrzej S.; Randolph, Ann; Keller, Benjamin J.; Werner, Thomas; Kretzler, Matthias

    2013-01-01

    Genome-wide association studies have proven to be highly effective at defining relationships between single nucleotide polymorphisms (SNPs) and clinical phenotypes in complex diseases. Establishing a mechanistic link between a noncoding SNP and the clinical outcome is a significant hurdle in translating associations into biological insight. We demonstrate an approach to assess the functional context of a diabetic nephropathy (DN)-associated SNP located in the promoter region of the gene FRMD3. The approach integrates pathway analyses with transcriptional regulatory pattern-based promoter modeling and allows the identification of a transcriptional framework affected by the DN-associated SNP in the FRMD3 promoter. This framework provides a testable hypothesis for mechanisms of genomic variation and transcriptional regulation in the context of DN. Our model proposes a possible transcriptional link through which the polymorphism in the FRMD3 promoter could influence transcriptional regulation within the bone morphogenetic protein (BMP)-signaling pathway. These findings provide the rationale to interrogate the biological link between FRMD3 and the BMP pathway and serve as an example of functional genomics-based hypothesis generation. PMID:23434934

  16. SNP Discovery in the Transcriptome of White Pacific Shrimp Litopenaeus vannamei by Next Generation Sequencing

    PubMed Central

    Yu, Yang; Wei, Jiankai; Zhang, Xiaojun; Liu, Jingwen; Liu, Chengzhang; Li, Fuhua; Xiang, Jianhai

    2014-01-01

    The application of next generation sequencing technology has greatly facilitated high throughput single nucleotide polymorphism (SNP) discovery and genotyping in genetic research. In the present study, SNPs were discovered based on two transcriptomes of Litopenaeus vannamei (L. vannamei) generated from Illumina sequencing platform HiSeq 2000. One transcriptome of L. vannamei was obtained through sequencing on the RNA from larvae at mysis stage and its reference sequence was de novo assembled. The data from another transcriptome were downloaded from NCBI and the reads of the two transcriptomes were mapped separately to the assembled reference by BWA. SNP calling was performed using SAMtools. A total of 58,717 and 36,277 SNPs with high quality were predicted from the two transcriptomes, respectively. SNP calling was also performed using the reads of two transcriptomes together, and a total of 96,040 SNPs with high quality were predicted. Among these 96,040 SNPs, 5,242 and 29,129 were predicted as non-synonymous and synonymous SNPs respectively. Characterization analysis of the predicted SNPs in L. vannamei showed that the estimated SNP frequency was 0.21% (one SNP per 476 bp) and the estimated ratio for transition to transversion was 2.0. Fifty SNPs were randomly selected for validation by Sanger sequencing after PCR amplification and 76% of SNPs were confirmed, which indicated that the SNPs predicted in this study were reliable. These SNPs will be very useful for genetic study in L. vannamei, especially for the high density linkage map construction and genome-wide association studies. PMID:24498047

  17. De novo sequencing of sunflower genome for SNP discovery using RAD (Restriction site Associated DNA) approach

    PubMed Central

    2013-01-01

    Background Application of Single Nucleotide Polymorphism (SNP) marker technology as a tool in sunflower breeding programs offers enormous potential to improve sunflower genetics, and facilitate faster release of sunflower hybrids to the market place. Through a National Sunflower Association (NSA) funded initiative, we report on the process of SNP discovery through reductive genome sequencing and local assembly of six diverse sunflower inbred lines that represent oil as well as confection types. Results A combination of Restriction site Associated DNA Sequencing (RAD-Seq) protocols and Illumina paired-end sequencing chemistry generated high quality 89.4 M paired end reads from the six lines which represent 5.3 GB of the sequencing data. Raw reads from the sunflower line, RHA 464 were assembled de novo to serve as a framework reference genome. About 15.2 Mb of sunflower genome distributed over 42,267 contigs were obtained upon assembly of RHA 464 sequencing data, the contig lengths ranged from 200 to 950 bp with an N50 length of 393 bp. SNP calling was performed by aligning sequencing data from the six sunflower lines to the assembled reference RHA 464. On average, 1 SNP was located every 143 bp of the sunflower genome sequence. Based on several filtering criteria, a final set of 16,467 putative sequence variants with characteristics favorable for Illumina Infinium Genotyping Technology (IGT) were mined from the sequence data generated across six diverse sunflower lines. Conclusion Here we report the molecular and computational methodology involved in SNP development for a complex genome like sunflower lacking reference assembly, offering an attractive tool for molecular breeding purposes in sunflower. PMID:23947483

  18. Prognostic significance of interleukin-6 single nucleotide polymorphism genotypes in neuroblastoma: rs1800795 (promoter) and rs8192284 (receptor)

    PubMed Central

    Lagmay, Joanne P.; London, Wendy B.; Gross, Thomas G.; Termuhlen, Amanda; Sullivan, Nicholas; Axel, Amy; Mundy, Bethany; Ranalli, Mark; Canner, Jason; McGrady, Patrick; Hall, Brett

    2009-01-01

    Purpose Neuroblastoma is a childhood cancer of the sympathetic nervous system and many patients present with high risk disease. Risk stratification, based on pathology and tumor-derived biomarkers, has improved prediction of clinical outcomes, but overall survival rates remain unfavorable and new therapeutic targets are needed. Some studies suggest a link between interleukin-6 and more aggressive behavior in neuroblastoma tumor cells. Therefore, we examined the impact of two IL-6 single nucleotide polymorphisms (SNP) on neuroblastoma disease progression. Experimental design DNA samples from 96 high risk neuroblastoma patients were screened for two SNP that are known to regulate the serum levels of IL-6 and the soluble IL-6 receptor (IL-6R), rs1800795 and rs8192284 respectively. The genotype for each SNP was determined in a blinded fashion and independent statistical analysis was performed to determine SNP-related event free survival (EFS) and overall survival (OS) rates. Results The rs1800795 IL-6 promoter SNP is an independent prognostic factor for EFS and OS in -high risk neuroblastoma patients. In contrast, the rs8192284 IL-6 receptor SNP revealed no prognostic value. Conclusions The rs1800795 SNP (-174 IL-6 (G>C) represents a novel and independent prognostic marker for both EFS and OS in high risk neuroblastoma. Since the rs1800795 SNP (-174 IL-6 (G>C) has been shown to correlate with production of IL-6, this cytokine may represent a target for development of new therapies in neuroblastoma. PMID:19671870

  19. OTG-snpcaller: An Optimized Pipeline Based on TMAP and GATK for SNP Calling from Ion Torrent Data

    PubMed Central

    Huang, Wenpan; Xi, Feng; Lin, Lin; Zhi, Qihuan; Zhang, Wenwei; Tang, Y. Tom; Geng, Chunyu; Lu, Zhiyuan; Xu, Xun

    2014-01-01

    Because the new Proton platform from Life Technologies produced markedly different data from those of the Illumina platform, the conventional Illumina data analysis pipeline could not be used directly. We developed an optimized SNP calling method using TMAP and GATK (OTG-snpcaller). This method combined our own optimized processes, Remove Duplicates According to AS Tag (RDAST) and Alignment Optimize Structure (AOS), together with TMAP and GATK, to call SNPs from Proton data. We sequenced four sets of exomes captured by Agilent SureSelect and NimbleGen SeqCap EZ Kit, using Life Technology’s Ion Proton sequencer. Then we applied OTG-snpcaller and compared our results with the results from Torrent Variants Caller. The results indicated that OTG-snpcaller can reduce both false positive and false negative rates. Moreover, we compared our results with Illumina results generated by GATK best practices, and we found that the results of these two platforms were comparable. The good performance in variant calling using GATK best practices can be primarily attributed to the high quality of the Illumina sequences. PMID:24824529

  20. Capillary electrophoresis of an 11-plex mtDNA coding region SNP single base extension assay for discrimination of the most common Caucasian HV1/HV2 mitotype.

    PubMed

    Vallone, Peter M

    2012-01-01

    The typing of single nucleotide polymorphisms (SNPs) located throughout the human mitochondrial genome assists in resolving individuals with an identical HV1/HV2 haplotype. A set of 11 sites which were selected for distinguishing individuals of a common Western European Caucasian HV1/HV2 mitotype was incorporated into a single base extension (SBE) assay. The assay was optimized for multiplex detection of sequence polymorphisms at positions 3010, 4793, 10211, 5004, 7028, 7202, 16519, 12858, 4580, 477, and 14470 in the mitochondrial genome. PCR primers were designed to allow for multiplex amplification of unique regions in the mitochondrial genome followed by an 11-plex SBE reaction using the SNaPshot(®) reagent kit. Separation and detection can be accomplished with a capillary-based electrophoresis platform commonly found in most forensic laboratories. PMID:22139659

  1. KinSNP software for homozygosity mapping of disease genes using SNP microarrays.

    PubMed

    Amir, El-Ad David; Bartal, Ofer; Morad, Efrat; Nagar, Tal; Sheynin, Jony; Parvari, Ruti; Chalifa-Caspi, Vered

    2010-08-01

    Consanguineous families affected with a recessive genetic disease caused by homozygotisation of a mutation offer a unique advantage for positional cloning of rare diseases. Homozygosity mapping of patient genotypes is a powerful technique for the identification of the genomic locus harbouring the causing mutation. This strategy relies on the observation that in these patients a large region spanning the disease locus is also homozygous with high probability. The high marker density in single nucleotide polymorphism (SNP) arrays is extremely advantageous for homozygosity mapping. We present KinSNP, a user-friendly software tool for homozygosity mapping using SNP arrays. The software searches for stretches of SNPs which are homozygous to the same allele in all ascertained sick individuals. User-specified parameters control the number of allowed genotyping 'errors' within homozygous blocks. Candidate disease regions are then reported in a detailed, coloured Excel file, along with genotypes of family members and healthy controls. An interactive genome browser has been included which shows homozygous blocks, individual genotypes, genes and further annotations along the chromosomes, with zooming and scrolling capabilities. The software has been used to identify the location of a mutated gene causing insensitivity to pain in a large Bedouin family. KinSNP is freely available from. PMID:20846928

  2. A High-Resolution SNP Array-Based Linkage Map Anchors a New Domestic Cat Draft Genome Assembly and Provides Detailed Patterns of Recombination.

    PubMed

    Li, Gang; Hillier, LaDeana W; Grahn, Robert A; Zimin, Aleksey V; David, Victor A; Menotti-Raymond, Marilyn; Middleton, Rondo; Hannah, Steven; Hendrickson, Sher; Makunin, Alex; O'Brien, Stephen J; Minx, Pat; Wilson, Richard K; Lyons, Leslie A; Warren, Wesley C; Murphy, William J

    2016-01-01

    High-resolution genetic and physical maps are invaluable tools for building accurate genome assemblies, and interpreting results of genome-wide association studies (GWAS). Previous genetic and physical maps anchored good quality draft assemblies of the domestic cat genome, enabling the discovery of numerous genes underlying hereditary disease and phenotypes of interest to the biomedical science and breeding communities. However, these maps lacked sufficient marker density to order thousands of shorter scaffolds in earlier assemblies, which instead relied heavily on comparative mapping with related species. A high-resolution map would aid in validating and ordering chromosome scaffolds from existing and new genome assemblies. Here, we describe a high-resolution genetic linkage map of the domestic cat genome based on genotyping 453 domestic cats from several multi-generational pedigrees on the Illumina 63K SNP array. The final maps include 58,055 SNP markers placed relative to 6637 markers with unique positions, distributed across all autosomes and the X chromosome. Our final sex-averaged maps span a total autosomal length of 4464 cM, the longest described linkage map for any mammal, confirming length estimates from a previous microsatellite-based map. The linkage map was used to order and orient the scaffolds from a substantially more contiguous domestic cat genome assembly (Felis catus v8.0), which incorporated ∼20 × coverage of Illumina fragment reads. The new genome assembly shows substantial improvements in contiguity, with a nearly fourfold increase in N50 scaffold size to 18 Mb. We use this map to report probable structural errors in previous maps and assemblies, and to describe features of the recombination landscape, including a massive (∼50 Mb) recombination desert (of virtually zero recombination) on the X chromosome that parallels a similar desert on the porcine X chromosome in both size and physical location. PMID:27172201

  3. A High-Resolution SNP Array-Based Linkage Map Anchors a New Domestic Cat Draft Genome Assembly and Provides Detailed Patterns of Recombination

    PubMed Central

    Li, Gang; Hillier, LaDeana W.; Grahn, Robert A.; Zimin, Aleksey V.; David, Victor A.; Menotti-Raymond, Marilyn; Middleton, Rondo; Hannah, Steven; Hendrickson, Sher; Makunin, Alex; O’Brien, Stephen J.; Minx, Pat; Wilson, Richard K.; Lyons, Leslie A.; Warren, Wesley C.; Murphy, William J.

    2016-01-01

    High-resolution genetic and physical maps are invaluable tools for building accurate genome assemblies, and interpreting results of genome-wide association studies (GWAS). Previous genetic and physical maps anchored good quality draft assemblies of the domestic cat genome, enabling the discovery of numerous genes underlying hereditary disease and phenotypes of interest to the biomedical science and breeding communities. However, these maps lacked sufficient marker density to order thousands of shorter scaffolds in earlier assemblies, which instead relied heavily on comparative mapping with related species. A high-resolution map would aid in validating and ordering chromosome scaffolds from existing and new genome assemblies. Here, we describe a high-resolution genetic linkage map of the domestic cat genome based on genotyping 453 domestic cats from several multi-generational pedigrees on the Illumina 63K SNP array. The final maps include 58,055 SNP markers placed relative to 6637 markers with unique positions, distributed across all autosomes and the X chromosome. Our final sex-averaged maps span a total autosomal length of 4464 cM, the longest described linkage map for any mammal, confirming length estimates from a previous microsatellite-based map. The linkage map was used to order and orient the scaffolds from a substantially more contiguous domestic cat genome assembly (Felis catus v8.0), which incorporated ∼20 × coverage of Illumina fragment reads. The new genome assembly shows substantial improvements in contiguity, with a nearly fourfold increase in N50 scaffold size to 18 Mb. We use this map to report probable structural errors in previous maps and assemblies, and to describe features of the recombination landscape, including a massive (∼50 Mb) recombination desert (of virtually zero recombination) on the X chromosome that parallels a similar desert on the porcine X chromosome in both size and physical location. PMID:27172201

  4. Genotyping-by-Sequencing SNP Identification for Crops without a Reference Genome: Using Transcriptome Based Mapping as an Alternative Strategy.

    PubMed

    Berthouly-Salazar, Cécile; Mariac, Cédric; Couderc, Marie; Pouzadoux, Juliette; Floc'h, Jean-Baptiste; Vigouroux, Yves

    2016-01-01

    Next-generation sequencing opens the way for genomic studies of diversity even for non-model crops and animals. Genome reduction techniques are becoming progressively more popular as they allow a fraction of the genome to be sequenced for multiple individuals and/or populations. These techniques are an efficient way to explore genome diversity in non-model crops and animals for which no reference genome is available. Genome reduction techniques emerged with the development of specific pipelines such as UNEAK (Universal Network Enabled Analysis Kit) and Stacks. However, even for non-model crops and animals, transcriptomes are easier to obtain, thereby making it possible to directly map reads. We investigate the direct use of transcriptome as an alternative strategy. Our specific objective was to compare SNPs obtained from the UNEAK pipeline as well as SNPs obtained by directly mapping genotyping-by-sequencing reads on a transcriptome. We assessed the feasibility of both SNP datasets, UNEAK and transcriptome mapping, to investigate the diversity of 91 samples of wild pearl millet sampled across its distribution area. Both approaches produced several tens of thousands of single nucleotide variants, but differed in the way the variants were identified, leading to differences in the frequency spectrum associated with marked differences in the assessment of diversity. Difference in the frequency spectrum significantly biased a large set of diversity analyses as well as detection of selection approaches. However, whatever the approach, we found very similar inference of genetic structure, with three major genetic groups from West, Central, and East Africa. For non-model crops, using transcriptome data as a reference is thus a particularly promising way to obtain a more thorough analysis of datasets generated using genome reduction techniques. PMID:27379109

  5. Genotyping-by-Sequencing SNP Identification for Crops without a Reference Genome: Using Transcriptome Based Mapping as an Alternative Strategy

    PubMed Central

    Berthouly-Salazar, Cécile; Mariac, Cédric; Couderc, Marie; Pouzadoux, Juliette; Floc’h, Jean-Baptiste; Vigouroux, Yves

    2016-01-01

    Next-generation sequencing opens the way for genomic studies of diversity even for non-model crops and animals. Genome reduction techniques are becoming progressively more popular as they allow a fraction of the genome to be sequenced for multiple individuals and/or populations. These techniques are an efficient way to explore genome diversity in non-model crops and animals for which no reference genome is available. Genome reduction techniques emerged with the development of specific pipelines such as UNEAK (Universal Network Enabled Analysis Kit) and Stacks. However, even for non-model crops and animals, transcriptomes are easier to obtain, thereby making it possible to directly map reads. We investigate the direct use of transcriptome as an alternative strategy. Our specific objective was to compare SNPs obtained from the UNEAK pipeline as well as SNPs obtained by directly mapping genotyping-by-sequencing reads on a transcriptome. We assessed the feasibility of both SNP datasets, UNEAK and transcriptome mapping, to investigate the diversity of 91 samples of wild pearl millet sampled across its distribution area. Both approaches produced several tens of thousands of single nucleotide variants, but differed in the way the variants were identified, leading to differences in the frequency spectrum associated with marked differences in the assessment of diversity. Difference in the frequency spectrum significantly biased a large set of diversity analyses as well as detection of selection approaches. However, whatever the approach, we found very similar inference of genetic structure, with three major genetic groups from West, Central, and East Africa. For non-model crops, using transcriptome data as a reference is thus a particularly promising way to obtain a more thorough analysis of datasets generated using genome reduction techniques. PMID:27379109

  6. The Perils of SNP Microarray Testing: Uncovering Unexpected Consanguinity

    PubMed Central

    Tarini, Beth A.; Konczal, Laura; Goldenberg, Aaron J.; Goldman, Edward B.; McCandless, Shawn E.

    2013-01-01

    Background While single nucleotide polymorphism (SNP) chromosomal microarrays identify areas of small genetic deletions/duplications, they can also reveal regions of homozygosity indicative of consanguinity. As more non-geneticists order SNP microarrays, they must prepare for the potential ethical, legal and social issues that result from revelation of unanticipated consanguinity. Patient An infant with multiple congenital anomalies underwent SNP microarray testing. Results The results of the SNP microarray revealed several large regions of homozygosity that indicated identity by descent most consistent with a second or third degree relative mating (e.g., uncle/ niece, half brother/sister, first cousins). Mother was not aware of the test's potential to reveal consanguinity. When informed of the test results, she reluctantly admitted to being raped by her half-brother around the time of conception. Conclusions During the pre-testing consent process, providers should inform parents that SNP microarray testing could reveal consanguinity. Providers must also understand the psychological implications, as well as the legal and moral obligations, that accompany SNP microarray results that indicate consanguinity. PMID:23827427

  7. Identification of SNP barcode biomarkers for genes associated with facial emotion perception using particle swarm optimization algorithm

    PubMed Central

    2014-01-01

    Background Facial emotion perception (FEP) can affect social function. We previously reported that parts of five tested single-nucleotide polymorphisms (SNPs) in the MET and AKT1 genes may individually affect FEP performance. However, the effects of SNP-SNP interactions on FEP performance remain unclear. Methods This study compared patients with high and low FEP performances (n = 89 and 93, respectively). A particle swarm optimization (PSO) algorithm was used to identify the best SNP barcodes (i.e., the SNP combinations and genotypes that revealed the largest differences between the high and low FEP groups). Results The analyses of individual SNPs showed no significant differences between the high and low FEP groups. However, comparisons of multiple SNP-SNP interactions involving different combinations of two to five SNPs showed that the best PSO-generated SNP barcodes were significantly associated with high FEP score. The analyses of the joint effects of the best SNP barcodes for two to five interacting SNPs also showed that the best SNP barcodes had significantly higher odds ratios (2.119 to 3.138; P < 0.05) compared to other SNP barcodes. In conclusion, the proposed PSO algorithm effectively identifies the best SNP barcodes that have the strongest associations with FEP performance. Conclusions This study also proposes a computational methodology for analyzing complex SNP-SNP interactions in social cognition domains such as recognition of facial emotion. PMID:24955105

  8. A Bayesian Framework for SNP Identification

    SciTech Connect

    Webb-Robertson, Bobbie-Jo M.; Havre, Susan L.; Payne, Deborah A.

    2005-07-01

    Current proteomics techniques, such as mass spectrometry, focus on protein identification, usually ignoring most types of modifications beyond post-translational modifications, with the assumption that only a small number of peptides have to be matched to a protein for a positive identification. However, not all proteins are being identified with current techniques and improved methods to locate points of mutation are becoming a necessity. In the case when single-nucleotide polymorphisms (SNPs) are observed, brute force is the most common method to locate them, quickly becoming computationally unattractive as the size of the database associated with the model organism grows. We have developed a Bayesian model for SNPs, BSNP, incorporating evolutionary information at both the nucleotide and amino acid levels. Formulating SNPs as a Bayesian inference problem allows probabilities of interest to be easily obtained, for example the probability of a specific SNP or specific type of mutation over a gene or entire genome. Three SNP databases were observed in the evaluation of the BSNP model; the first SNP database is a disease specific gene in human, hemoglobin, the second is also a disease specific gene in human, p53, and the third is a more general SNP database for multiple genes in mouse. We validate that the BSNP model assigns higher posterior probabilities to the SNPs defined in all three separate databases than can be attributed to chance under specific evolutionary information, for example the amino acid model described by Majewski and Ott in conjunction with either the four-parameter nucleotide model by Bulmer or seven-parameter nucleotide model by Majewski and Ott.

  9. Ultrahigh-density linkage map for cultivated cucumber (Cucumis sativus L.) using a single-nucleotide polymorphism genotyping array

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With the low cost of single nucleotide polymorphism (SNP) discovery, use of SNP markers for SNP array development is becoming more affordable. The SNP array is a very useful tool for high throughput genotyping and has a number of applications such as genome-wide association studies (GWAS). Since the...

  10. WISP1 Polymorphisms Contribute to Platinum-Based Chemotherapy Toxicity in Lung Cancer Patients

    PubMed Central

    Chen, Juan; Yin, Jiye; Li, Xiangping; Wang, Ying; Zheng, Yi; Qian, Chenyue; Xiao, Ling; Zou, Ting; Wang, Zhan; Liu, Junyan; Zhang, Wei; Zhou, Honghao; Liu, Zhaoqian

    2014-01-01

    Platinum-based chemotherapy toxicity is always one of the serious problems from which lung cancer patients suffer. The genetic polymorphism of WISP1 was revealed to be associated with susceptibility and platinum-based chemotherapy response in our previous studies. In this study, we aimed to investigate the relationship of WISP1 genetic polymorphisms with platinum-based chemotherapy toxicity in lung cancer patients. A total of 412 lung cancer patients were enrolled in this study, and 28 polymorphisms of the WISP1 gene were genotyped by SequenomMassARRAY. We found that WISP1 polymorphisms (rs2929965, rs2929969, rs2929970, rs2929973 and rs754958) were related to the overall chemotherapy toxicity of lung cancer in subgroup analyses. Rs16904853, rs2929970, rs2977549 and rs2977551 (p = 0.021, 0.028, 0.024, 0.048, respectively) polymorphisms were significantly associated with hematologic toxicity. Rs2929946, rs2929970, rs2977519, rs2977536, rs3739262 and rs754958 (p = 0.031, 0.046, 0.029, 0.016, 0.042, 0.035, respectively) polymorphisms were significantly associated with the gastrointestinal toxicity of lung cancer. Genotypes of WISP1 may be novel and useful biomarkers for predicting platinum-based chemotherapy toxicity in lung cancer patients. PMID:25405734

  11. Development of cleaved amplified polymorphic sequence markers and a CAPS-based genetic linkage map in watermelon (Citrullus lanatus [Thunb.] Matsum. and Nakai) constructed using whole-genome re-sequencing data

    PubMed Central

    Liu, Shi; Gao, Peng; Zhu, Qianglong; Luan, Feishi; Davis, Angela R.; Wang, Xiaolu

    2016-01-01

    Cleaved amplified polymorphic sequence (CAPS) markers are useful tools for detecting single nucleotide polymorphisms (SNPs). This study detected and converted SNP sites into CAPS markers based on high-throughput re-sequencing data in watermelon, for linkage map construction and quantitative trait locus (QTL) analysis. Two inbred lines, Cream of Saskatchewan (COS) and LSW-177 had been re-sequenced and analyzed by Perl self-compiled script for CAPS marker development. 88.7% and 78.5% of the assembled sequences of the two parental materials could map to the reference watermelon genome, respectively. Comparative assembled genome data analysis provided 225,693 and 19,268 SNPs and indels between the two materials. 532 pairs of CAPS markers were designed with 16 restriction enzymes, among which 271 pairs of primers gave distinct bands of the expected length and polymorphic bands, via PCR and enzyme digestion, with a polymorphic rate of 50.94%. Using the new CAPS markers, an initial CAPS-based genetic linkage map was constructed with the F2 population, spanning 1836.51 cM with 11 linkage groups and 301 markers. 12 QTLs were detected related to fruit flesh color, length, width, shape index, and brix content. These newly CAPS markers will be a valuable resource for breeding programs and genetic studies of watermelon. PMID:27162496

  12. Development of cleaved amplified polymorphic sequence markers and a CAPS-based genetic linkage map in watermelon (Citrullus lanatus [Thunb.] Matsum. and Nakai) constructed using whole-genome re-sequencing data.

    PubMed

    Liu, Shi; Gao, Peng; Zhu, Qianglong; Luan, Feishi; Davis, Angela R; Wang, Xiaolu

    2016-03-01

    Cleaved amplified polymorphic sequence (CAPS) markers are useful tools for detecting single nucleotide polymorphisms (SNPs). This study detected and converted SNP sites into CAPS markers based on high-throughput re-sequencing data in watermelon, for linkage map construction and quantitative trait locus (QTL) analysis. Two inbred lines, Cream of Saskatchewan (COS) and LSW-177 had been re-sequenced and analyzed by Perl self-compiled script for CAPS marker development. 88.7% and 78.5% of the assembled sequences of the two parental materials could map to the reference watermelon genome, respectively. Comparative assembled genome data analysis provided 225,693 and 19,268 SNPs and indels between the two materials. 532 pairs of CAPS markers were designed with 16 restriction enzymes, among which 271 pairs of primers gave distinct bands of the expected length and polymorphic bands, via PCR and enzyme digestion, with a polymorphic rate of 50.94%. Using the new CAPS markers, an initial CAPS-based genetic linkage map was constructed with the F2 population, spanning 1836.51 cM with 11 linkage groups and 301 markers. 12 QTLs were detected related to fruit flesh color, length, width, shape index, and brix content. These newly CAPS markers will be a valuable resource for breeding programs and genetic studies of watermelon. PMID:27162496

  13. Applying SNP-Derived Molecular Coancestry Estimates to Captive Breeding Programs.

    PubMed

    Ivy, Jamie A; Putnam, Andrea S; Navarro, Asako Y; Gurr, Jessica; Ryder, Oliver A

    2016-09-01

    Captive breeding programs for wildlife species typically rely on pedigrees to inform genetic management. Although pedigree-based breeding strategies are quite effective at retaining long-term genetic variation, management of zoo-based breeding programs continues to be hampered when pedigrees are poorly known. The objective of this study was to evaluate 2 options for generating single nucleotide polymorphism (SNP) data to resolve unknown relationships within captive breeding programs. We generated SNP data for a zoo-based population of addax (Addax nasomasculatus) using both the Illumina BovineHD BeadChip and double digest restriction site-associated DNA (ddRAD) sequencing. Our results demonstrated that estimates of allele sharing (AS) between pairs of individuals exhibited low variances. Average AS variances were highest when using 50 loci (SNPchipall = 0.00159; ddRADall = 0.0249), but fell below 0.0003 for the SNP chip dataset when sampling ≥250 loci and below 0.0025 for the ddRAD dataset when sampling ≥500 loci. Furthermore, the correlation between the SNPchipall and ddRADall AS datasets was 0.88 (95%CI = 0.84-0.91) when subsampling 500 loci. Collectively, our results indicated that both SNP genotyping methods produced sufficient data for accurately estimating relationships, even within an extremely bottlenecked population. Our results also suggested that analytic assumptions historically integrated into the addax pedigree are not adversely impacting long-term pedigree-based management; kinships calculated from the analytic pedigree were significantly correlated (P < 0.001) with AS estimates. Overall, our conclusions are intended to serve as both a proof of concept and a model for applying molecular data to the genetic management of captive breeding programs. PMID:27208150

  14. Association between two single base polymorphisms of intercellular adhesion molecule 1 gene and inflammatory bowel disease

    PubMed Central

    Habibi, Manijeh; Naderi, Nosratllah; Farnood, Alma; Balaii, Hedieh; Dadaei, Tahereh; Almasi, Shohreh; Zojaji, Homayoun; Asadzadeh Aghdae, Hamid; Zali, Mohammad Reza

    2016-01-01

    Aim: The present study evaluated the association between G241R and K469E polymorphisms of intercellular adhesion molecule 1 gene and inflammatory bowel disease in Iranian population. Background: Inflammatory bowel disease including ulcerative colitis and Crohn’s disease, is a chronic idiopathic inflammatory disease of the gastrointestinal tract. There are two single base polymorphisms of intercellular adhesion molecule 1gene, G241R and K469E, reported to be associated with inflammatory disorders. Patients and methods: In this case-control study, 156 inflammatory bowel disease patients (110 ulcerative colitis and 46 Crohn’s disease patients) and 131 healthy controls were enrolled. Two polymorphisms of intercellular adhesion molecule 1 gene, including G241R and K469E, were assessed by polymerase chain reaction followed by restriction fragment length polymorphism. Results: The E469 allele of K469E polymorphism was significantly more frequent in Crohn’s disease patients compared to controls (P< 0.05, OR= 1.83; 95% CI: 1.13 to 2.96). The mutant homozygote genotype of K469E polymorphism (E/E) was also significantly more frequent in Crohn’s disease patients compared to controls (P< 0.05, OR= 4.23; 95% CI: 1.42 to 12.59). No difference was observed in the frequency of K469E polymorphism among ulcerative colitis patients compared to controls. There were no significant differences in genotype and allele frequencies of G241R polymorphism among ulcerative colitis and Crohn’s disease patients compared to control subjects. Conclusion: According to our findings, K469E polymorphism of intercellular adhesion molecule 1 gene may probably participate in the pathogenesis of Crohn’s disease in Iran. PMID:27099667

  15. SNPsplit: Allele-specific splitting of alignments between genomes with known SNP genotypes

    PubMed Central

    Krueger, Felix; Andrews, Simon R.

    2016-01-01

    Sequencing reads overlapping polymorphic sites in diploid mammalian genomes may be assigned to one allele or the other. This holds the potential to detect gene expression, chromatin modifications, DNA methylation or nuclear interactions in an allele-specific fashion. SNPsplit is an allele-specific alignment sorter designed to read files in SAM/BAM format and determine the allelic origin of reads or read-pairs that cover known single nucleotide polymorphic (SNP) positions. For this to work libraries must have been aligned to a genome in which all known SNP positions were masked with the ambiguity base 'N' and aligned using a suitable mapping program such as Bowtie2, TopHat, STAR, HISAT2, HiCUP or Bismark. SNPsplit also provides an automated solution to generate N-masked reference genomes for hybrid mouse strains based on the variant call information provided by the Mouse Genomes Project. The unique ability of SNPsplit to work with various different kinds of sequencing data including RNA-Seq, ChIP-Seq, Bisulfite-Seq or Hi-C opens new avenues for the integrative exploration of allele-specific data. PMID:27429743

  16. SNPsplit: Allele-specific splitting of alignments between genomes with known SNP genotypes.

    PubMed

    Krueger, Felix; Andrews, Simon R

    2016-01-01

    Sequencing reads overlapping polymorphic sites in diploid mammalian genomes may be assigned to one allele or the other. This holds the potential to detect gene expression, chromatin modifications, DNA methylation or nuclear interactions in an allele-specific fashion. SNPsplit is an allele-specific alignment sorter designed to read files in SAM/BAM format and determine the allelic origin of reads or read-pairs that cover known single nucleotide polymorphic (SNP) positions. For this to work libraries must have been aligned to a genome in which all known SNP positions were masked with the ambiguity base 'N' and aligned using a suitable mapping program such as Bowtie2, TopHat, STAR, HISAT2, HiCUP or Bismark. SNPsplit also provides an automated solution to generate N-masked reference genomes for hybrid mouse strains based on the variant call information provided by the Mouse Genomes Project. The unique ability of SNPsplit to work with various different kinds of sequencing data including RNA-Seq, ChIP-Seq, Bisulfite-Seq or Hi-C opens new avenues for the integrative exploration of allele-specific data. PMID:27429743

  17. Rapid and Efficient Identification of Caenorhabditis elegans Legacy Mutations Using Hawaiian SNP-Based Mapping and Whole-Genome Sequencing.

    PubMed

    Jaramillo-Lambert, Aimee; Fuchsman, Abigail S; Fabritius, Amy S; Smith, Harold E; Golden, Andy

    2015-05-01

    The production of viable embryos requires the coordination of many cellular processes, including protein synthesis, cytoskeletal reorganization, establishment of polarity, cell migration, cell division, and in Caenorhabditis elegans, eggshell formation. Defects in any of these processes can lead to embryonic lethality. We examined six temperature-sensitive mutants as well as one nonconditional mutant that were previously identified in genetic screens as either embryonic lethal (maternal-effect or zygotic lethal) or eggshell defective. The responsible molecular lesion for each had never been determined. After confirmation of temperature sensitivity and lethality, we performed whole-genome sequencing using a single-nucleotide polymorphism mapping strategy to pinpoint the molecular lesions. Gene candidates were confirmed by RNA interference phenocopy and/or complementation tests and one mutant was further validated by CRISPR (Clustered Regularly Interspaced Short Palidromic Repeats)/Cas9 gene editing. This approach identified new alleles of several genes that had only been previously studied by RNA interference depletion. Our identification of temperature-sensitive alleles for all of these essential genes provides an extremely useful tool for further investigation for the C. elegans community, such as the ability to address mutant phenotypes at various developmental stages and the ability to carry out suppressor/enhancer screens to identify other genes that function in a specific cellular process. PMID:25740937

  18. Rapid and Efficient Identification of Caenorhabditis elegans Legacy Mutations Using Hawaiian SNP-Based Mapping and Whole-Genome Sequencing

    PubMed Central

    Jaramillo-Lambert, Aimee; Fuchsman, Abigail S.; Fabritius, Amy S.; Smith, Harold E.; Golden, Andy

    2015-01-01

    The production of viable embryos requires the coordination of many cellular processes, including protein synthesis, cytoskeletal reorganization, establishment of polarity, cell migration, cell division, and in Caenorhabditis elegans, eggshell formation. Defects in any of these processes can lead to embryonic lethality. We examined six temperature-sensitive mutants as well as one nonconditional mutant that were previously identified in genetic screens as either embryonic lethal (maternal-effect or zygotic lethal) or eggshell defective. The responsible molecular lesion for each had never been determined. After confirmation of temperature sensitivity and lethality, we performed whole-genome sequencing using a single-nucleotide polymorphism mapping strategy to pinpoint the molecular lesions. Gene candidates were confirmed by RNA interference phenocopy and/or complementation tests and one mutant was further validated by CRISPR (Clustered Regularly Interspaced Short Palidromic Repeats)/Cas9 gene editing. This approach identified new alleles of several genes that had only been previously studied by RNA interference depletion. Our identification of temperature-sensitive alleles for all of these essential genes provides an extremely useful tool for further investigation for the C. elegans community, such as the ability to address mutant phenotypes at various developmental stages and the ability to carry out suppressor/enhancer screens to identify other genes that function in a specific cellular process. PMID:25740937

  19. Development of 101 novel EST-derived single nucleotide polymorphism markers for Zhikong scallop ( Chlamys farreri)

    NASA Astrophysics Data System (ADS)

    Li, Jiqin; Bao, Zhenmin; Li, Ling; Wang, Xiaojian; Wang, Shi; Hu, Xiaoli

    2013-09-01

    Zhikong scallop ( Chlamys farreri) is an important maricultured species in China. Many researches on this species, such as population genetics and QTL fine-mapping, need a large number of molecular markers. In this study, based on the expressed sequence tags (EST), a total of 300 putative single nucleotide polymorphisms (SNPs) were selected and validated using high resolution melting (HRM) technology with unlabeled probe. Of them, 101 (33.7%) were found to be polymorphic in 48 individuals from 4 populations. Further evaluation with 48 individuals from Qingdao population showed that all the polymorphic loci had two alleles with the minor allele frequency ranged from 0.046 to 0.500. The observed and expected heterozygosities ranged from 0.000 to 0.925 and from 0.089 to 0.505, respectively. Fifteen loci deviated significantly from Hardy-Weinberg equilibrium and significant linkage disequilibrate was detected in one pair of markers. BLASTx gave significant hits for 72 of the 101 polymorphic SNP-containing ESTs. Thirty four polymorphic SNP loci were predicted to be non-synonymous substitutions as they caused either the change of codons (33 SNPs) or pretermination of translation (1 SNP). The markers developed can be used for the population studies and genetic improvement on Zhikong scallop.

  20. MAFsnp: A Multi-Sample Accurate and Flexible SNP Caller Using Next-Generation Sequencing Data.

    PubMed

    Hu, Jiyuan; Li, Tengfei; Xiu, Zidi; Zhang, Hong

    2015-01-01

    Most existing statistical methods developed for calling single nucleotide polymorphisms (SNPs) using next-generation sequencing (NGS) data are based on Bayesian frameworks, and there does not exist any SNP caller that produces p-values for calling SNPs in a frequentist framework. To fill in this gap, we develop a new method MAFsnp, a Multiple-sample based Accurate and Flexible algorithm for calling SNPs with NGS data. MAFsnp is based on an estimated likelihood ratio test (eLRT) statistic. In practical situation, the involved parameter is very close to the boundary of the parametric space, so the standard large sample property is not suitable to evaluate the finite-sample distribution of the eLRT statistic. Observing that the distribution of the test statistic is a mixture of zero and a continuous part, we propose to model the test statistic with a novel two-parameter mixture distribution. Once the parameters in the mixture distribution are estimated, p-values can be easily calculated for detecting SNPs, and the multiple-testing corrected p-values can be used to control false discovery rate (FDR) at any pre-specified level. With simulated data, MAFsnp is shown to have much better control of FDR than the existing SNP callers. Through the application to two real datasets, MAFsnp is also shown to outperform the existing SNP callers in terms of calling accuracy. An R package "MAFsnp" implementing the new SNP caller is freely available at http://homepage.fudan.edu.cn/zhangh/softwares/. PMID:26309201

  1. PEAS V1.0: a package for elementary analysis of SNP data.

    PubMed

    Xu, Shuhua; Gupta, Sanchit; Jin, Li

    2010-11-01

    We have developed a software package named PEAS to facilitate analyses of large data sets of single nucleotide polymorphisms (SNPs) for population genetics and molecular phylogenetics studies. PEAS reads SNP data in various formats as input and is versatile in data formatting; using PEAS, it is easy to create input files for many popular packages, such as STRUCTURE, frappe, Arlequin, Haploview, LDhat, PLINK, EIGENSOFT, PHASE, fastPHASE, MEGA and PHYLIP. In addition, PEAS fills up several analysis gaps in currently available computer programs in population genetics and molecular phylogenetics. Notably, (i) It calculates genetic distance matrices with bootstrapping for both individuals and populations from genome-wide high-density SNP data, and the output can be streamlined to MEGA and PHYLIP programs for further processing; (ii) It calculates genetic distances from STRUCTURE output and generates MEGA file to reconstruct component trees; (iii) It provides tools to conduct haplotype sharing analysis for phylogenetic studies based on high-density SNP data. To our knowledge, these analyses are not available in any other computer program. PEAS for Windows is freely available for academic users from http://www.picb.ac.cn/~xushua/index.files/Download_PEAS.htm. PMID:21565121

  2. Generation of large numbers of SNP in cattle by coupling reduced genome representation with high throughput sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whole genome sequencing projects have produced draft sequences for species from diverse evolutionary clades for comparative evolutionary studies. Generally, these projects have not simultaneously created extensive single nucleotide polymorphism (SNP) resources for use in genetics studies within the...

  3. Whole genome SNP scanning of snow sheep (Ovis nivicola).

    PubMed

    Deniskova, T E; Okhlopkov, I M; Sermyagin, A A; Gladyr', E A; Bagirov, V A; Sölkner, J; Mamaev, N V; Brem, G; Zinov'eva, N A

    2016-07-01

    This is the first report performing the whole genome SNP scanning of snow sheep (Ovis nivicola). Samples of snow sheep (n = 18) collected in six different regions of the Republic of Sakha (Yakutia) from 64° to 71° N. For SNP genotyping, we applied Ovine 50K SNP BeadChip (Illumina, United States), designed for domestic sheep. The total number of genotyped SNPs (call rate 90%) was 47796 (88.1% of total SNPs), wherein 1006 SNPs were polymorphic (2.1%). Principal component analysis (PCA) showed the clear differentiation within the species O. nivicola: studied individuals were distributed among five distinct arrays corresponding to the geographical locations of sampling points. Our results demonstrate that the DNA chip designed for domestic sheep can be successfully used to study the allele pool and the genetic structure of snow sheep populations. PMID:27599514

  4. Detection of copy number variation by SNP-allelotyping.

    PubMed

    Parker, Brett; Alexander, Ryan; Wu, Xingyao; Feely, Shawna; Shy, Michael; Schnetz-Boutaud, Nathalie; Li, Jun

    2015-03-01

    Charcot-Marie-Tooth disease type 1A (CMT1A) is caused by an abnormal copy number variation (CNV) with a trisomy of chromosome 17p12. The increase of the DNA-segment copy number is expected to alter the allele frequency of single nucleotide polymorphism (SNP) within the duplicated region. We tested whether SNP allele frequency determined by a Sequenom MassArray can be used to detect the CMT1A mutation. Our results revealed distinct patterns of SNP allele frequency distribution, which reliably differentiated CMT1A patients from controls. This finding suggests that this technique may serve as an alternative approach to identifying CNV in certain diseases, including CMT1A. PMID:24830919

  5. Clinical Significance of Long Non-Coding RNA CASC8 rs10505477 Polymorphism in Lung Cancer Susceptibility, Platinum-Based Chemotherapy Response, and Toxicity

    PubMed Central

    Hu, Lei; Chen, Shu-Hui; Lv, Qiao-Li; Sun, Bao; Qu, Qiang; Qin, Chong-Zhen; Fan, Lan; Guo, Ying; Cheng, Lin; Zhou, Hong-Hao

    2016-01-01

    Long non-coding RNA (lncRNA) CASC8 rs10505477 polymorphism has been identified to be related to risk of many kinds of cancers, such as colorectal cancer, gastric cancer, and invasive ovarian cancer, and it may be involved in the prognosis of gastric cancer patients who have received platinum-based chemotherapy after surgical treatment. So far, there is no study investigating the clinical significance of lncRNA CASC8 rs10505477 in lung cancer susceptibility and treatment. In this study, we genotyped 498 lung cancer patients and 213 healthy control subjects to explore the correlation between the rs10505477 polymorphism and lung cancer risk in a Chinese population. Among the 498 patients, 467 were selected for the chemotherapy response and toxicity study. We found that the single nucleotide polymorphisms (SNP) rs10505477 was greatly related to lung cancer risk in male and adenocarcinoma subgroups in recessive model (adjusted OR = 0.51, 95%CI = 0.29–0.90, p = 0.02; adjusted OR = 0.52, 95%CI = 0.30–0.89, p = 0.02, respectively). It was also closely correlated with platinum-based chemotherapy response in dominant model (adjusted OR = 1.58, 95%CI = 1.05–2.39, p = 0.03). Additionally, we observed that CASC8 rs10505477 polymorphism was significantly relevant to severe hematologic toxicity in non-small-cell lung cancer (NSCLC) subgroup in dominant model (adjusted OR = 0.59, 95%CI = 0.35–0.98, p = 0.04) and in additive model (adjusted OR = 0.62, 95%CI = 0.43–0.90, p = 0.01). Furthermore, it was found that rs10505477 polymorphism was greatly associated with gastrointestinal toxicity in SCLC and cisplatin subgroups in dominant model (adjusted OR = 7.82, 95%CI = 1.36–45.07, p = 0.02; adjusted OR = 1.94, 95%CI = 1.07–3.53, p = 0.03, respectively). Thus, lncRNA CASC8 rs10505477 could serve as a possible risk marker for diagnosing lung cancer, and could be used to forecast the response and toxicity of platinum-based treatment in lung cancer patients. PMID:27249003

  6. MyD88 Polymorphisms and Association with Susceptibility to Salmonella Pullorum

    PubMed Central

    Liu, Xian-Qing; Wang, Fei; Jin, Jie; Zhou, Yu-Guang; Ran, Jin-Shan; Feng, Ze-Qing; Wang, Yan; Liu, Yi-Ping

    2015-01-01

    Myeloid differentiation primary response gene 88 (MYD88), a universal adapter protein, plays an important role in activating the nuclear factor-κB (NF-κB) and regulating the expression of proinflammatory genes like tumor necrosis factor (TNF) and interleukin-1 (IL-1), which were highly involved in Salmonella Pullorum infection. To detect the relationship between polymorphisms of the MyD88 gene and Salmonella Pullorum disease, we screened the coding region (CDS) of the MYD88 gene by DNA pool construction and sequencing based on case-control study. Eight single nucleotide polymorphisms (SNPs) in the sequenced fragment (5 exons), 7 known loci and one novel mutation named G4810372T (SNP8), were found in the fifth exon. In addition, we found 7 nonsynonymous substitutions. The allele frequency of only one SNP, g.4810191C > T (SNP1), was significantly different (P < 0.05) between case and control groups. The genotype frequencies of SNP1 (g.4810191C > T) and SNP3 (g.4810257G > T) were of significant difference between the case and the control groups (P < 0.05). Collectively, SNPs of the MyD88 gene were significantly associated with susceptibility to Salmonella Pullorum infection, which can be used as a disease-resistant marker in chicken. These results provided a theoretical basis for future research on chicken breeding by marker-assisted selection. PMID:26881204

  7. Single-nucleotide-polymorphism-based association mapping of dog stereotypes.

    PubMed

    Jones, Paul; Chase, Kevin; Martin, Alan; Davern, Pluis; Ostrander, Elaine A; Lark, Karl G

    2008-06-01

    Phenotypic stereotypes are traits, often polygenic, that have been stringently selected to conform to specific criteria. In dogs, Canis familiaris, stereotypes result from breed standards set for conformation, performance (behaviors), etc. As a consequence, phenotypic values measured on a few individuals are representative of the breed stereotype. We used DNA samples isolated from 148 dog breeds to associate SNP markers with breed stereotypes. Using size as a trait to test the method, we identified six significant quantitative trait loci (QTL) on five chromosomes that include candidate genes appropriate to regulation of size (e.g., IGF1, IGF2BP2 SMAD2, etc.). Analysis of other morphological stereotypes, also under extreme selection, identified many additional significant loci. Less well-documented data for behavioral stereotypes tentatively identified loci for herding, pointing, boldness, and trainability. Four significant loci were identified for longevity, a breed characteristic not under direct selection, but inversely correlated with breed size. The strengths and limitations of the approach are discussed as well as its potential to identify loci regulating the within-breed incidence of specific polygenic diseases. PMID:18505865

  8. Genotyping NAT2 with only two SNPs (rs1041983 and rs1801280) outperforms the tagging SNP rs1495741 and is equivalent to the conventional 7-SNP NAT2 genotype.

    PubMed

    Selinski, Silvia; Blaszkewicz, Meinolf; Lehmann, Marie-Louise; Ovsiannikov, Daniel; Moormann, Oliver; Guballa, Christoph; Kress, Alexander; Truss, Michael C; Gerullis, Holger; Otto, Thomas; Barski, Dimitri; Niegisch, Günter; Albers, Peter; Frees, Sebastian; Brenner, Walburgis; Thüroff, Joachim W; Angeli-Greaves, Miriam; Seidel, Thilo; Roth, Gerhard; Dietrich, Holger; Ebbinghaus, Rainer; Prager, Hans M; Bolt, Hermann M; Falkenstein, Michael; Zimmermann, Anna; Klein, Torsten; Reckwitz, Thomas; Roemer, Hermann C; Löhlein, Dietrich; Weistenhöfer, Wobbeke; Schöps, Wolfgang; Hassan Rizvi, Syed Adibul; Aslam, Muhammad; Bánfi, Gergely; Romics, Imre; Steffens, Michael; Ekici, Arif B; Winterpacht, Andreas; Ickstadt, Katja; Schwender, Holger; Hengstler, Jan G; Golka, Klaus

    2011-10-01

    Genotyping N-acetyltransferase 2 (NAT2) is of high relevance for individualized dosing of antituberculosis drugs and bladder cancer epidemiology. In this study we compared a recently published tagging single nucleotide polymorphism (SNP) (rs1495741) to the conventional 7-SNP genotype (G191A, C282T, T341C, C481T, G590A, A803G and G857A haplotype pairs) and systematically analysed if novel SNP combinations outperform the latter. For this purpose, we studied 3177 individuals by PCR and phenotyped 344 individuals by the caffeine test. Although the tagSNP and the 7-SNP genotype showed a high degree of correlation (R=0.933, P<0.0001) the 7-SNP genotype nevertheless outperformed the tagging SNP with respect to specificity (1.0 vs. 0.9444, P=0.0065). Considering all possible SNP combinations in a receiver operating characteristic analysis we identified a 2-SNP genotype (C282T, T341C) that outperformed the tagging SNP and was equivalent to the 7-SNP genotype. The 2-SNP genotype predicted the correct phenotype with a sensitivity of 0.8643 and a specificity of 1.0. In addition, it predicted the 7-SNP genotype with sensitivity and specificity of 0.9993 and 0.9880, respectively. The prediction of the NAT2 genotype by the 2-SNP genotype performed similar in populations of Caucasian, Venezuelan and Pakistani background. A 2-SNP genotype predicts NAT2 phenotypes with similar sensitivity and specificity as the conventional 7-SNP genotype. This procedure represents a facilitation in individualized dosing of NAT2 substrates without losing sensitivity or specificity. PMID:21750470

  9. Mining for single nucleotide polymorphisms and insertions / deletions in expressed sequence tag libraries of oil palm.

    PubMed

    Riju, Aykkal; Chandrasekar, Arumugam; Arunachalam, Vadivel

    2007-01-01

    The oil palm is a tropical oil bearing tree. Recently EST-derived SNPs and SSRs are a free by-product of the currently expanding EST (Expressed Sequence Tag) data bases. The development of high-throughput methods for the detection of SNPs (Single Nucleotide Polymorphism) and small indels (insertion / deletion) has led to a revolution in their use as molecular markers. Available (5452) Oil palm EST sequences were mined from dbEST of NCBI. CAP3 program was used to assemble EST sequences into contigs. Candidate SNPs and Indel polymorphisms were detected using the perl script auto_snip version 1.0 which has used 576 ESTs for detecting SNPs and Indel sites. We found 1180 SNP sites and 137 indel polymorphisms with frequency 1.36 SNPs / 100 bp. Among the six tissues from which the EST libraries had been generated, mesocarp had high frequency of 2.91 SNPs and indels per 100 bp whereas the zygotic embryos had lowest frequency of 0.15 per 100 bp. We also used the Shannon index to analyze the proportion of ten possible types of SNP/indels. ESTs from tissues of normal apex showed highest values of Shannon index (0.60) whereas abnormal apex had least value (0.02). The present report deals the use of Shannon index for comparing SNP/ indel frequencies mined from ESTlibraries and also confirm that the frequency of SNP occurrence in oil palm to use them as markers for genetic studies. PMID:21670789

  10. Calcium carbonate polymorph control using droplet-based microfluidics.

    PubMed

    Yashina, Alexandra; Meldrum, Fiona; Demello, Andrew

    2012-06-01

    Calcium carbonate (CaCO(3)) is one of the most abundant minerals and of high importance in many areas of science including global CO(2) exchange, industrial water treatment energy storage, and the formation of shells and skeletons. Industrially, calcium carbonate is also used in the production of cement, glasses, paints, plastics, rubbers, ceramics, and steel, as well as being a key material in oil refining and iron ore purification. CaCO(3) displays a complex polymorphic behaviour which, despite numerous experiments, remains poorly characterised. In this paper, we report the use of a segmented-flow microfluidic reactor for the controlled precipitation of calcium carbonate and compare the resulting crystal properties with those obtained using both continuous flow microfluidic reactors and conventional bulk methods. Through combination of equal volumes of equimolar aqueous solutions of calcium chloride and sodium carbonate on the picoliter scale, it was possible to achieve excellent definition of both crystal size and size distribution. Furthermore, highly reproducible control over crystal polymorph could be realised, such that pure calcite, pure vaterite, or a mixture of calcite and vaterite could be precipitated depending on the reaction conditions and droplet-volumes employed. In contrast, the crystals precipitated in the continuous flow and bulk systems comprised of a mixture of calcite and vaterite and exhibited a broad distribution of sizes for all reaction conditions investigated. PMID:22655005

  11. Effect of supersaturation on L-glutamic acid polymorphs under droplet-based microchannels

    NASA Astrophysics Data System (ADS)

    Jiang, Nan; Wang, Zhanzhong; Dang, Leping; Wei, Hongyuan

    2016-07-01

    Supersaturation is an important controlling factor for crystallization process and polymorphism. Droplet-based microchannels and conventional crystallization were used to investigate polymorphs of L-gluatamic acid in this work. The results illustrate that it is easy to realize the accurate and rapid control of the crystallization temperature in the droplets, which is especially beneficial to heat and mass transfer during crystallization. It is also noted that higher degree of supersaturation favors the nucleation of α crystal form, while lower degree of supersaturation favors the nucleation of β crystal form under droplet-based microchannels for L-gluatamic acid. In addition, there is a different nucleation behavior to be found under droplet-based microchannels both for the β form and α form of L-glutamic acid. This new finding can provide important insight into the development and design of investigation meanings for drug polymorph.

  12. Polymorphisms in base excision repair genes as colorectal cancer risk factors and modifiers of the effect of diets high in red meat

    PubMed Central

    Brevik, Asgeir; Joshi, Amit D.; Corral, Román; Onland-Moret, N. Charlotte; Siegmund, Kimberly D.; Le Marchand, Loïc; Baron, John A.; Martinez, Maria Elena; Haile, Robert W.; Ahnen, Dennis J.; Sandler, Robert S.; Lance, Peter; Stern, Mariana C.

    2010-01-01

    Background A diet high in red meat is an established colorectal cancer (CRC) risk factor. Carcinogens generated during meat cooking have been implicated as causal agents, and can induce oxidative DNA damage, which elicits repair by the base excision repair (BER) pathway. Methods Using a family-based study we investigated the role of polymorphisms in four BER genes (APEX1 Gln51His, Asp148Glu; OGG1 Ser236Cys; PARP Val742Ala; XRCC1 Arg194Trp, Arg280His, Arg399Gln) as potential CRC risk factors and modifiers of the association between high-red meat or poultry diets and CRC risk. We tested for gene-environment interactions using case-only analyses (N = 577) and compared statistically significant results to those obtained using case-unaffected sibling comparisons (N = 307 sibships). Results Carriers of the APEX1 codon 51 Gln/His genotype had a reduced CRC risk compared to carriers of the Gln/Gln genotype (OR 0.15, 95% CI 0.03-0.69, p = 0.015). The association between higher red meat intake (>3 servings/week) and CRC was modified by the PARP Val762Ala SNP (case-only interaction p = 0.026). This SNP also modified the association between higher intake of high-temperature cooked red meat (case-only interaction p = 0.0009). Conclusions We report evidence that the BER pathway PARP gene modifies the association of diets high in red meat cooked at high temperatures with risk of CRC. Impact Our findings suggest a contribution to colorectal carcinogenesis of free radical damage as one of the possible harmful effects of a high-red meat diet. PMID:21037106

  13. SNP Discovery Using Next Generation Transcriptomic Sequencing in Atlantic Herring (Clupea harengus)

    PubMed Central

    Bekkevold, Dorte; Babbucci, Massimiliano; van Houdt, Jeroen; Maes, Gregory E.; Bargelloni, Luca; Nielsen, Rasmus O.; Taylor, Martin I.; Ogden, Rob; Cariani, Alessia; Carvalho, Gary R.; Consortium, FishPopTrace; Panitz, Frank

    2012-01-01

    The introduction of Next Generation Sequencing (NGS) has revolutionised population genetics, providing studies of non-model species with unprecedented genomic coverage, allowing evolutionary biologists to address questions previously far beyond the reach of available resources. Furthermore, the simple mutation model of Single Nucleotide Polymorphisms (SNPs) permits cost-effective high-throughput genotyping in thousands of individuals simultaneously. Genomic resources are scarce for the Atlantic herring (Clupea harengus), a small pelagic species that sustains high revenue fisheries. This paper details the development of 578 SNPs using a combined NGS and high-throughput genotyping approach. Eight individuals covering the species distribution in the eastern Atlantic were bar-coded and multiplexed into a single cDNA library and sequenced using the 454 GS FLX platform. SNP discovery was performed by de novo sequence clustering and contig assembly, followed by the mapping of reads against consensus contig sequences. Selection of candidate SNPs for genotyping was conducted using an in silico approach. SNP validation and genotyping were performed simultaneously using an Illumina 1,536 GoldenGate assay. Although the conversion rate of candidate SNPs in the genotyping assay cannot be predicted in advance, this approach has the potential to maximise cost and time efficiencies by avoiding expensive and time-consuming laboratory stages of SNP validation. Additionally, the in silico approach leads to lower ascertainment bias in the resulting SNP panel as marker selection is based only on the ability to design primers and the predicted presence of intron-exon boundaries. Consequently SNPs with a wider spectrum of minor allele frequencies (MAFs) will be genotyped in the final panel. The genomic resources presented here represent a valuable multi-purpose resource for developing informative marker panels for population discrimination, microarray development and for population

  14. Evolutionary patterns of DNA base composition and correlation to polymorphisms in DNA repair systems

    PubMed Central

    Li, Xianran; Scanlon, Michael J.; Yu, Jianming

    2015-01-01

    DNA base composition is a fundamental genome feature. However, the evolutionary pattern of base composition and its potential causes have not been well understood. Here, we report findings from comparative analysis of base composition at the whole-genome level across 2210 species, the polymorphic-site level across eight population comparison sets, and the mutation-site level in 12 mutation-tracking experiments. We first demonstrate that base composition follows the individual-strand base equality rule at the genome, chromosome and polymorphic-site levels. More intriguingly, clear separation of base-composition values calculated across polymorphic sites was consistently observed between basal and derived groups, suggesting common underlying mechanisms. Individuals in the derived groups show an A&T-increase/G&C-decrease pattern compared with the basal groups. Spontaneous and induced mutation experiments indicated these patterns of base composition change can emerge across mutation sites. With base-composition across polymorphic sites as a genome phenotype, genome scans with human 1000 Genomes and HapMap3 data identified a set of significant genomic regions enriched with Gene Ontology terms for DNA repair. For three DNA repair genes (BRIP1, PMS2P3 and TTDN), ENCODE data provided evidence for interaction between genomic regions containing these genes and regions containing the significant SNPs. Our findings provide insights into the mechanisms of genome evolution. PMID:25765652

  15. HapMap tag-SNP analysis confirms a role for COMT in schizophrenia risk and reveals a novel association.

    PubMed

    Voisey, J; Swagell, C D; Hughes, I P; Lawford, B R; Young, R M; Morris, C P

    2012-07-01

    Catechol-O-methyl transferase (COMT) encodes an enzyme involved in the metabolism of dopamine and maps to a commonly deleted region that increases schizophrenia risk. A non-synonymous polymorphism (rs4680) in COMT has been previously found to be associated with schizophrenia and results in altered activity levels of COMT. Using a haplotype block-based gene-tagging approach we conducted an association study of seven COMT single nucleotide polymorphisms (SNPs) in 160 patients with a DSM-IV diagnosis of schizophrenia and 250 controls in an Australian population. Two polymorphisms including rs4680 and rs165774 were found to be significantly associated with schizophrenia. The rs4680 results in a Val/Met substitution but the strongest association was shown by the novel SNP, rs165774, which may still be functional even though it is located in intron five. Individuals with schizophrenia were more than twice as likely to carry the GG genotype compared to the AA genotype for both the rs165774 and rs4680 SNPs. This association was slightly improved when males were analysed separately possibly indicating a degree of sexual dimorphism. Our results confirm that COMT is a good candidate for schizophrenia risk, by replicating the association with rs4680 and identifying a novel SNP association. PMID:20934310

  16. Development of EST Intron-Targeting SNP Markers for Panax ginseng and Their Application to Cultivar Authentication.

    PubMed

    Wang, Hongtao; Li, Guisheng; Kwon, Woo-Saeng; Yang, Deok-Chun

    2016-01-01

    Panax ginseng is one of the most valuable medicinal plants in the Orient. The low level of genetic variation has limited the application of molecular markers for cultivar authentication and marker-assisted selection in cultivated ginseng. To exploit DNA polymorphism within ginseng cultivars, ginseng expressed sequence tags (ESTs) were searched against the potential intron polymorphism (PIP) database to predict the positions of introns. Intron-flanking primers were then designed in conserved exon regions and used to amplify across the more variable introns. Sequencing results showed that single nucleotide polymorphisms (SNPs), as well as indels, were detected in four EST-derived introns, and SNP markers specific to "Gopoong" and "K-1" were first reported in this study. Based on cultivar-specific SNP sites, allele-specific polymerase chain reaction (PCR) was conducted and proved to be effective for the authentication of ginseng cultivars. Additionally, the combination of a simple NaOH-Tris DNA isolation method and real-time allele-specific PCR assay enabled the high throughput selection of cultivars from ginseng fields. The established real-time allele-specific PCR assay should be applied to molecular authentication and marker assisted selection of P. ginseng cultivars, and the EST intron-targeting strategy will provide a potential approach for marker development in species without whole genomic DNA sequence information. PMID:27271615

  17. Development of EST Intron-Targeting SNP Markers for Panax ginseng and Their Application to Cultivar Authentication

    PubMed Central

    Wang, Hongtao; Li, Guisheng; Kwon, Woo-Saeng; Yang, Deok-Chun

    2016-01-01

    Panax ginseng is one of the most valuable medicinal plants in the Orient. The low level of genetic variation has limited the application of molecular markers for cultivar authentication and marker-assisted selection in cultivated ginseng. To exploit DNA polymorphism within ginseng cultivars, ginseng expressed sequence tags (ESTs) were searched against the potential intron polymorphism (PIP) database to predict the positions of introns. Intron-flanking primers were then designed in conserved exon regions and used to amplify across the more variable introns. Sequencing results showed that single nucleotide polymorphisms (SNPs), as well as indels, were detected in four EST-derived introns, and SNP markers specific to “Gopoong” and “K-1” were first reported in this study. Based on cultivar-specific SNP sites, allele-specific polymerase chain reaction (PCR) was conducted and proved to be effective for the authentication of ginseng cultivars. Additionally, the combination of a simple NaOH-Tris DNA isolation method and real-time allele-specific PCR assay enabled the high throughput selection of cultivars from ginseng fields. The established real-time allele-specific PCR assay should be applied to molecular authentication and marker assisted selection of P. ginseng cultivars, and the EST intron-targeting strategy will provide a potential approach for marker development in species without whole genomic DNA sequence information. PMID:27271615

  18. Accuracy of genomic selection in barley breeding programs: a simulation study based on the real SNP data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study was to compare the accuracy of genomic selection (i.e., selection based on genome-wide markers) to phenotypic selection through simulations based on real barley SNPs data (1325 SNPs x 863 breeding lines). We simulated 100 QTL at randomly selected SNPs, which were dropped from t...

  19. Assessing host-specificity of Escherichia coli using a supervised learning logic-regression-based analysis of single nucleotide polymorphisms in intergenic regions.

    PubMed

    Zhi, Shuai; Li, Qiaozhi; Yasui, Yutaka; Edge, Thomas; Topp, Edward; Neumann, Norman F

    2015-11-01

    Host specificity in E. coli is widely debated. Herein, we used supervised learning logic-regression-based analysis of intergenic DNA sequence variability in E. coli in an attempt to identify single nucleotide polymorphism (SNP) biomarkers of E. coli that are associated with natural selection and evolution toward host specificity. Seven-hundred and eighty strains of E. coli were isolated from 15 different animal hosts. We utilized logic regression for analyzing DNA sequence data of three intergenic regions (flanked by the genes uspC-flhDC, csgBAC-csgDEFG, and asnS-ompF) to identify genetic biomarkers that could potentially discriminate E. coli based on host sources. Across 15 different animal hosts, logic regression successfully discriminated E. coli based on animal host source with relatively high specificity (i.e., among the samples of the non-target animal host, the proportion that correctly did not have the host-specific marker pattern) and sensitivity (i.e., among the samples from a given animal host, the proportion that correctly had the host-specific marker pattern), even after fivefold cross validation. Permutation tests confirmed that for most animals, host specific intergenic biomarkers identified by logic regression in E. coli were significantly associated with animal host source. The highest level of biomarker sensitivity was observed in deer isolates, with 82% of all deer E. coli isolates displaying a unique SNP pattern that was 98% specific to deer. Fifty-three percent of human isolates displayed a unique biomarker pattern that was 98% specific to humans. Twenty-nine percent of cattle isolates displayed a unique biomarker that was 97% specific to cattle. Interestingly, even within a related host group (i.e., Family: Canidae [domestic dogs and coyotes]), highly specific SNP biomarkers (98% and 99% specificity for dog and coyotes, respectively) were observed, with 21% of dog E. coli isolates displaying a unique dog biomarker and 61% of coyote isolates

  20. Population genetic variation of the Southern Ocean krill, Euphausia superba, in the Western Antarctic Peninsula region based on mitochondrial single nucleotide polymorphisms (SNPs)

    NASA Astrophysics Data System (ADS)

    Batta-Lona, Paola G.; Bucklin, Ann; Wiebe, Peter H.; Patarnello, Tomaso; Copley, Nancy J.

    2011-07-01

    The Southern Ocean krill, Euphausia superba, is one of the best-studied marine zooplankton species in terms of population genetic diversity and structure; with few exceptions, previous studies have shown the species to be genetically homogeneous at larger spatial scales. The goals of this study are to examine sub-regional scale population genetic diversity and structure of E. superba using molecular characters selected with this goal in mind, and to thereby examine hypotheses of the source(s) of recruitment for krill populations of the Western Antarctic Peninsula (WAP). Collections were made throughout the WAP region during US GLOBEC cruises in austral fall, 2001 and 2002. A total of 585 E. superba (including all 6 furcilia larval stages, juveniles, and adults) was analyzed after confirmation of species identification using a competitive multiplexed species-specific PCR (SS-PCR) reaction based on mitochondrial cytochrome oxidase I (mtCOI) sequences. The molecular markers used were allele frequencies at single nucleotide polymorphism (SNP) sites in the gene encoding mitochondrial Cytochrome b (cyt b). Four SNP sites that showed desirable patterns of allelic variation were selected; alleles were detected using a multiplexed single-base extension PCR protocol. A total of 22 SNP haplotypes (i.e., strings of polymorphisms at the four SNP sites) was observed; haplotype diversity (Hd)=0.811 (s.d.=0.008). Analysis of molecular variation within and among samples, areas (i.e., Marguerite Bay, Crystal Sound, shelf, and offshore) and collection years revealed no difference between 2001 and 2002 collections overall, although differences between 2001 and 2002 collections from Marguerite Bay explained 7.4% of the variance ( FST=0.072; p=0.002±0.001). Most of the variation (96.3%) occurred within samples each year, with no significant differentiation among areas. There was small, but significant differentiation among samples within areas in 2001 (4.6%; FST=0.045; p=0.015±0

  1. SNP sets and reading ability: testing confirmation of a 10-SNP set in a population sample.

    PubMed

    Luciano, Michelle; Montgomery, Grant W; Martin, Nicholas G; Wright, Margaret J; Bates, Timothy C

    2011-06-01

    A set of 10 SNPs associated with reading ability in 7-year-olds was reported based on initial pooled analyses of 100K SNP chip data, with follow-up testing stages using pooling and individual testing. Here we examine this association in an adolescent population sample of Australian twins and siblings (N = 1177) aged 12 to 25 years. One (rs1842129) of the 10 SNPs approached significance (P = .05) but no support was found for the remaining 9 SNPs or the SNP set itself. Results indicate that these SNPs are not associated with reading ability in an Australian population. The results are interpreted as supporting use of much larger SNP sets in common disorders where effects are small. PMID:21623652

  2. Cross-Species Application of SNP Chips is Not Suitable for Identifying Runs of Homozygosity.

    PubMed

    Shafer, Aaron B A; Miller, Joshua M; Kardos, Marty

    2016-03-01

    Cross-species application of single-nucleotide polymorphism (SNP) chips is a valid, relatively cost-effective alternative to the high-throughput sequencing methods generally required to obtain a genome-wide sampling of polymorphisms. Kharzinova et al. (2015) examined the applicability of SNP chips developed in domestic bovids (cattle and sheep) to a semi-wild cervid (reindeer). The ancestors of bovids and cervids diverged between 20 and 30 million years ago (Hassanin and Douzery 2003; Bibi et al. 2013). Empirical work has shown that for a SNP chip developed in a bovid and applied to a cervid species, approximately 50% genotype success with 1% of the loci being polymorphic is expected (Miller et al. 2012). The genotyping of Kharzinova et al. (2015) follows this pattern; however, these data are not appropriate for identifying runs of homozygosity (ROH) and can be problematic for estimating linkage disequilibrium (LD) and we caution readers in this regard. PMID:26774056

  3. STAT3 polymorphisms may predict an unfavorable response to first-line platinum-based therapy for women with advanced serous epithelial ovarian cancer

    PubMed Central

    Permuth-Wey, Jennifer; Fulp, William J.; Reid, Brett M.; Chen, Zhihua; Georgeades, Christina; Cheng, Jin Q.; Magliocco, Anthony; Chen, Dung-Tsa; Lancaster, Johnathan M.

    2016-01-01

    Cancer stem cells (CSC) contribute to epithelial ovarian cancer (EOC) progression and therapeutic response. We hypothesized that germline single nucleotide polymorphisms (SNPs) in CSC-related genes may predict an initial therapeutic response for women newly diagnosed with EOC. A nested case–control design was used to study 361 women with advanced-stage serous EOC treated with surgery followed by first-line platinum-based combination therapy at Moffitt Cancer Center or as part of The Cancer Genome Atlas Study. “Cases” included 102 incomplete responders (IRs) and “controls” included 259 complete clinical responders (CRs) to therapy. Using Illumina genotyping arrays and imputation, DNA samples were evaluated for 5,509 SNPs in 24 ovarian CSC-related genes. We also evaluated the overall significance of each CSC gene using the admixture maximum likelihood (AML) test, and correlated genotype with EOC tumor tissue expression. The strongest SNP-level associations with an IR to therapy were identified for correlated (r2 > 0.80) SNPs within signal transducer and activator of transcription 3 (STAT3) [odds ratio (OR), 2.24; 95% confidence interval (CI), 1.32–3.78; p = 0.0027], after adjustment for age, population stratification, grade and residual disease. At the gene level, STAT3 was significantly associated with an IR to therapy (pAML 5 0.006). rs1053004, a STAT3 SNP in a putative miRNA-binding site, was associated with STAT3 expression (p = 0.057). This is the first study to identify germline STAT3 variants as independent predictors of an unfavorable therapeutic response for EOC patients. Findings suggest that STAT3 genotype may identify high-risk women likely to respond more favorably to novel therapeutic combinations that include STAT3 inhibitors. PMID:26264211

  4. The role of WWOX polymorphisms on COPD susceptibility and pulmonary function traits in Chinese: a case-control study and family-based analysis

    PubMed Central

    Xie, Chenli; Chen, Xiaoliang; Qiu, Fuman; Zhang, Lisha; Wu, Di; Chen, Jiansong; Yang, Lei; Lu, Jiachun

    2016-01-01

    Single nucleotide polymorphisms (SNPs) in the WW domain containing oxidoreductase (WWOX) gene were recently identified to be quantitative trait loci for lung function and thus likely to be susceptible biomarkers for COPD. However, the associations between WWOX SNPs and COPD risk are still unclear. Here, by conducting a two-center case-control study including 1511 COPD cases and 1677 controls and a family-based analysis comprising 95 nuclear pedigrees, we tested the associations between five SNPs that are rs10220974C >T, rs3764340C >G, rs12918952G >A, rs383362G >T, rs12828G >A of WWOX and COPD risk as well as the hereditary inclination of these loci among COPD families. We found that the SNP rs383362G >T was significantly associated with an increased risk of COPD in a T allele-number dependent-manner (OR = 1.30, 95%CI = 1.11 - 1.52). The T allele was more prone to over transmit to sick children and sibs than the G allele (Z = 2.900, P = 0.004). Moreover, the forced expiratory volume in one second/forced vital capacity (FEV1/FVC), FEV1/predicted-FEV1 and annual FEV1 also significantly decreased in the rs383362T carriers compared to the rs383362GG carriers. For other SNPs, no significant association was observed for COPD and pulmonary function. Taken together, our data demonstrated that the SNP rs383362G >T of WWOX plays a role in COPD inheritance. PMID:26902998

  5. STAT3 polymorphisms may predict an unfavorable response to first-line platinum-based therapy for women with advanced serous epithelial ovarian cancer.

    PubMed

    Permuth-Wey, Jennifer; Fulp, William J; Reid, Brett M; Chen, Zhihua; Georgeades, Christina; Cheng, Jin Q; Magliocco, Anthony; Chen, Dung-Tsa; Lancaster, Johnathan M

    2016-02-01

    Cancer stem cells (CSC) contribute to epithelial ovarian cancer (EOC) progression and therapeutic response. We hypothesized that germline single nucleotide polymorphisms (SNPs) in CSC-related genes may predict an initial therapeutic response for women newly diagnosed with EOC. A nested case-control design was used to study 361 women with advanced-stage serous EOC treated with surgery followed by first-line platinum-based combination therapy at Moffitt Cancer Center or as part of The Cancer Genome Atlas Study. "Cases" included 102 incomplete responders (IRs) and "controls" included 259 complete clinical responders (CRs) to therapy. Using Illumina genotyping arrays and imputation, DNA samples were evaluated for 5,509 SNPs in 24 ovarian CSC-related genes. We also evaluated the overall significance of each CSC gene using the admixture maximum likelihood (AML) test, and correlated genotype with EOC tumor tissue expression. The strongest SNP-level associations with an IR to therapy were identified for correlated (r(2) > 0.80) SNPs within signal transducer and activator of transcription 3 (STAT3) [odds ratio (OR), 2.24; 95% confidence interval (CI), 1.32-3.78; p = 0.0027], after adjustment for age, population stratification, grade and residual disease. At the gene level, STAT3 was significantly associated with an IR to therapy (pAML = 0.006). rs1053004, a STAT3 SNP in a putative miRNA-binding site, was associated with STAT3 expression (p = 0.057). This is the first study to identify germline STAT3 variants as independent predictors of an unfavorable therapeutic response for EOC patients. Findings suggest that STAT3 genotype may identify high-risk women likely to respond more favorably to novel therapeutic combinations that include STAT3 inhibitors. PMID:26264211

  6. Family-based study of brain-derived neurotrophic factor (BDNF) gene polymorphism in alcohol dependence.

    PubMed

    Grzywacz, Anna; Samochowiec, Agnieszka; Ciechanowicz, Andrzej; Samochowiec, Jerzy

    2010-01-01

    Brain-derived neurotrophic factor (BDNF) belongs to a family of proteins related to the nerve growth factor family, which are responsible for the proliferation, survival and differentiation of neurons. BDNF is thought to be involved in the pathogenesis of bipolar disorder, schizophrenia, eating disorders and addiction. We hypothesize that a functionally relevant polymorphism of the BDNF gene promoter may be associated with the pathogenesis of alcohol dependence. We performed an association study of 141 families with alcohol dependence. One hundred and thirty-eight healthy control subjects were matched based on ethnicity and gender. An association between the BDNF Val66Met gene polymorphism and alcoholism was not found. PMID:21098877

  7. Introgression browser: high-throughput whole-genome SNP visualization.

    PubMed

    Aflitos, Saulo Alves; Sanchez-Perez, Gabino; de Ridder, Dick; Fransz, Paul; Schranz, Michael E; de Jong, Hans; Peters, Sander A

    2015-04-01

    Breeding by introgressive hybridization is a pivotal strategy to broaden the genetic basis of crops. Usually, the desired traits are monitored in consecutive crossing generations by marker-assisted selection, but their analyses fail in chromosome regions where crossover recombinants are rare or not viable. Here, we present the Introgression Browser (iBrowser), a bioinformatics tool aimed at visualizing introgressions at nucleotide or SNP (Single Nucleotide Polymorphisms) accuracy. The software selects homozygous SNPs from Variant Call Format (VCF) information and filters out heterozygous SNPs, multi-nucleotide polymorphisms (MNPs) and insertion-deletions (InDels). For data analysis iBrowser makes use of sliding windows, but if needed it can generate any desired fragmentation pattern through General Feature Format (GFF) information. In an example of tomato (Solanum lycopersicum) accessions we visualize SNP patterns and elucidate both position and boundaries of the introgressions. We also show that our tool is capable of identifying alien DNA in a panel of the closely related S. pimpinellifolium by examining phylogenetic relationships of the introgressed segments in tomato. In a third example, we demonstrate the power of the iBrowser in a panel of 597 Arabidopsis accessions, detecting the boundaries of a SNP-free region around a polymorphic 1.17 Mbp inverted segment on the short arm of chromosome 4. The architecture and functionality of iBrowser makes the software appropriate for a broad set of analyses including SNP mining, genome structure analysis, and pedigree analysis. Its functionality, together with the capability to process large data sets and efficient visualization of sequence variation, makes iBrowser a valuable breeding tool. PMID:25704554

  8. A high-density, SNP-based consensus map of tetraploid wheat as a bridge to integrate durum and bread wheat genomics and breeding.

    PubMed

    Maccaferri, Marco; Ricci, Andrea; Salvi, Silvio; Milner, Sara Giulia; Noli, Enrico; Martelli, Pier Luigi; Casadio, Rita; Akhunov, Eduard; Scalabrin, Simone; Vendramin, Vera; Ammar, Karim; Blanco, Antonio; Desiderio, Francesca; Distelfeld, Assaf; Dubcovsky, Jorge; Fahima, Tzion; Faris, Justin; Korol, Abraham; Massi, Andrea; Mastrangelo, Anna Maria; Morgante, Michele; Pozniak, Curtis; N'Diaye, Amidou; Xu, Steven; Tuberosa, Roberto

    2015-06-01

    Consensus linkage maps are important tools in crop genomics. We have assembled a high-density tetraploid wheat consensus map by integrating 13 data sets from independent biparental populations involving durum wheat cultivars (Triticum turgidum ssp. durum), cultivated emmer (T. turgidum ssp. dicoccum) and their ancestor (wild emmer, T. turgidum ssp. dicoccoides). The consensus map harboured 30 144 markers (including 26 626 SNPs and 791 SSRs) half of which were present in at least two component maps. The final map spanned 2631 cM of all 14 durum wheat chromosomes and, differently from the individual component maps, all markers fell within the 14 linkage groups. Marker density per genetic distance unit peaked at centromeric regions, likely due to a combination of low recombination rate in the centromeric regions and even gene distribution along the chromosomes. Comparisons with bread wheat indicated fewer regions with recombination suppression, making this consensus map valuable for mapping in the A and B genomes of both durum and bread wheat. Sequence similarity analysis allowed us to relate mapped gene-derived SNPs to chromosome-specific transcripts. Dense patterns of homeologous relationships have been established between the A- and B-genome maps and between nonsyntenic homeologous chromosome regions as well, the latter tracing to ancient translocation events. The gene-based homeologous relationships are valuable to infer the map location of homeologs of target loci/QTLs. Because most SNP and SSR markers were previously mapped in bread wheat, this consensus map will facilitate a more effective integration and exploitation of genes and QTL for wheat breeding purposes. PMID:25424506

  9. Genetic contributions to avoidance-based decisions: striatal D2 receptor polymorphisms.

    PubMed

    Frank, M J; Hutchison, K

    2009-11-24

    Individuals differ in their tendencies to seek positive decision outcomes or to avoid negative ones. At the neurobiological level, our model suggests that phasic changes in dopamine support learning to reinforce good decisions via striatal D1 receptors, and to avoid maladaptive choices via striatal D2 receptors. Accordingly, in a previous study individual differences in positive and negative learning were strongly modulated by two genetic polymorphisms factors related to striatal D1 and D2 function, respectively. Nevertheless, whereas the role for dopamine in positive learning is relatively well accepted, that in learning to avoid negative outcomes is more controversial. Here we further explore D2-receptor-related genetic contributions to probabilistic avoidance in humans, in light of recent data showing that particular DRD2 polymorphisms are associated with functional modulation of receptor expression [Zhang Y, Bertolino A, Fazio L, Blasi G, Rampino A, Romano R, Lee M-LT, Xiao T, Papp A, Wang D, Sadée W (2007) Polymorphisms in human dopamine d2 receptor gene affect gene expression, splicing, and neuronal activity during working memory. Proc Natl Acad Sci U S A 104(51):20552-20557]. We find that a promoter polymorphism rs12364283 associated with transcription and D2 receptor density was strongly and selectively predictive of avoidance-based decisions. Two further polymorphisms (rs2283265 and rs1076560) associated with relatively reduced presynaptic relative to postsynaptic D2 receptor expression were predictive of relative impairments in negative compared to positive decisions. These previously undocumented effects of DRD2 polymorphisms were largely independent of those we reported previously for the C957T polymorphism (rs6277) associated with striatal D2 density. In contrast, effects of the commonly studied Taq1A polymorphism on reinforcement-based decisions were due to indirect association with C957T. Taken together these findings suggest multiple D2-dependent

  10. VaDE: a manually curated database of reproducible associations between various traits and human genomic polymorphisms.

    PubMed

    Nagai, Yoko; Takahashi, Yasuko; Imanishi, Tadashi

    2015-01-01

    Genome-wide association studies (GWASs) have identified numerous single nucleotide polymorphisms (SNPs) associated with the development of common diseases. However, it is clear that genetic risk factors of common diseases are heterogeneous among human populations. Therefore, we developed a database of genomic polymorphisms that are reproducibly associated with disease susceptibilities, drug responses and other traits for each human population: 'VarySysDB Disease Edition' (VaDE; http://bmi-tokai.jp/VaDE/). SNP-trait association data were obtained from the National Human Genome Research Institute GWAS (NHGRI GWAS) catalog and RAvariome, and we added detailed information of sample populations by curating original papers. In addition, we collected and curated original papers, and registered the detailed information of SNP-trait associations in VaDE. Then, we evaluated reproducibility of associations in each population by counting the number of significantly associated studies. VaDE provides literature-based SNP-trait association data and functional genomic region annotation for SNP functional research. SNP functional annotation data included experimental data of the ENCODE project, H-InvDB transcripts and the 1000 Genome Project. A user-friendly web interface was developed to assist quick search, easy download and fast swapping among viewers. We believe that our database will contribute to the future establishment of personalized medicine and increase our understanding of genetic factors underlying diseases. PMID:25361969

  11. Rapid Diagnosis of Imprinting Disorders Involving Copy Number Variation and Uniparental Disomy Using Genome-Wide SNP Microarrays.

    PubMed

    Liu, Weiqiang; Zhang, Rui; Wei, Jun; Zhang, Huimin; Yu, Guojiu; Li, Zhihua; Chen, Min; Sun, Xiaofang

    2015-01-01

    Imprinting disorders, such as Beckwith-Wiedemann syndrome (BWS), Prader-Willi syndrome (PWS) and Angelman syndrome (AS), can be detected via methylation analysis, methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA), or other methods. In this study, we applied single nucleotide polymorphism (SNP)-based chromosomal microarray analysis to detect copy number variations (CNVs) and uniparental disomy (UPD) events in patients with suspected imprinting disorders. Of 4 patients, 2 had a 5.25-Mb microdeletion in the 15q11.2q13.2 region, 1 had a 38.4-Mb mosaic UPD in the 11p15.4 region, and 1 had a 60-Mb detectable UPD between regions 14q13.2 and 14q32.13. Although the 14q32.2 region was classified as normal by SNP array for the 14q13 UPD patient, it turned out to be a heterodisomic UPD by short tandem repeat marker analysis. MS-MLPA analysis was performed to validate the variations. In conclusion, SNP-based microarray is an efficient alternative method for quickly and precisely diagnosing PWS, AS, BWS, and other imprinted gene-associated disorders when considering aberrations due to CNVs and most types of UPD. PMID:26184742

  12. Differential Single Nucleotide Polymorphism-Based Analysis of an Outbreak Caused by Salmonella enterica Serovar Manhattan Reveals Epidemiological Details Missed by Standard Pulsed-Field Gel Electrophoresis

    PubMed Central

    Scaltriti, Erika; Sassera, Davide; Comandatore, Francesco; Morganti, Marina; Mandalari, Carmen; Gaiarsa, Stefano; Bandi, Claudio; Zehender, Gianguglielmo; Bolzoni, Luca; Casadei, Gabriele

    2015-01-01

    We retrospectively analyzed a rare Salmonella enterica serovar Manhattan outbreak that occurred in Italy in 2009 to evaluate the potential of new genomic tools based on differential single nucleotide polymorphism (SNP) analysis in comparison with the gold standard genotyping method, pulsed-field gel electrophoresis. A total of 39 isolates were analyzed from patients (n = 15) and food, feed, animal, and environmental sources (n = 24), resulting in five different pulsed-field gel electrophoresis (PFGE) profiles. Isolates epidemiologically related to the outbreak clustered within the same pulsotype, SXB_BS.0003, without any further differentiation. Thirty-three isolates were considered for genomic analysis based on different sets of SNPs, core, synonymous, nonsynonymous, as well as SNPs in different codon positions, by Bayesian and maximum likelihood algorithms. Trees generated from core and nonsynonymous SNPs, as well as SNPs at the second and first plus second codon positions detailed four distinct groups of isolates within the outbreak pulsotype, discriminating outbreak-related isolates of human and food origins. Conversely, the trees derived from synonymous and third-codon-position SNPs clustered food and human isolates together, indicating that all outbreak-related isolates constituted a single clone, which was in line with the epidemiological evidence. Further experiments are in place to extend this approach within our regional enteropathogen surveillance system. PMID:25653407

  13. High-density SNP assay development for genetic analysis in maritime pine (Pinus pinaster).

    PubMed

    Plomion, C; Bartholomé, J; Lesur, I; Boury, C; Rodríguez-Quilón, I; Lagraulet, H; Ehrenmann, F; Bouffier, L; Gion, J M; Grivet, D; de Miguel, M; de María, N; Cervera, M T; Bagnoli, F; Isik, F; Vendramin, G G; González-Martínez, S C

    2016-03-01

    Maritime pine provides essential ecosystem services in the south-western Mediterranean basin, where it covers around 4 million ha. Its scattered distribution over a range of environmental conditions makes it an ideal forest tree species for studies of local adaptation and evolutionary responses to climatic change. Highly multiplexed single nucleotide polymorphism (SNP) genotyping arrays are increasingly used to study genetic variation in living organisms and for practical applications in plant and animal breeding and genetic resource conservation. We developed a 9k Illumina Infinium SNP array and genotyped maritime pine trees from (i) a three-generation inbred (F2) pedigree, (ii) the French breeding population and (iii) natural populations from Portugal and the French Atlantic coast. A large proportion of the exploitable SNPs (2052/8410, i.e. 24.4%) segregated in the mapping population and could be mapped, providing the densest ever gene-based linkage map for this species. Based on 5016 SNPs, natural and breeding populations from the French gene pool exhibited similar level of genetic diversity. Population genetics and structure analyses based on 3981 SNP markers common to the Portuguese and French gene pools revealed high levels of differentiation, leading to the identification of a set of highly differentiated SNPs that could be used for seed provenance certification. Finally, we discuss how the validated SNPs could facilitate the identification of ecologically and economically relevant genes in this species, improving our understanding of the demography and selective forces shaping its natural genetic diversity, and providing support for new breeding strategies. PMID:26358548

  14. Software solutions for the livestock genomics SNP array revolution.

    PubMed

    Nicolazzi, E L; Biffani, S; Biscarini, F; Orozco Ter Wengel, P; Caprera, A; Nazzicari, N; Stella, A

    2015-08-01

    Since the beginning of the genomic era, the number of available single nucleotide polymorphism (SNP) arrays has grown considerably. In the bovine species alone, 11 SNP chips not completely covered by intellectual property are currently available, and the number is growing. Genomic/genotype data are not standardized, and this hampers its exchange and integration. In addition, software used for the analyses of these data usually requires not standard (i.e. case specific) input files which, considering the large amount of data to be handled, require at least some programming skills in their production. In this work, we describe a software toolkit for SNP array data management, imputation, genome-wide association studies, population genetics and genomic selection. However, this toolkit does not solve the critical need for standardization of the genotypic data and software input files. It only highlights the chaotic situation each researcher has to face on a daily basis and gives some helpful advice on the currently available tools in order to navigate the SNP array data complexity. PMID:25907889

  15. Genetic diversity in Capsicum germplasm based on microsatellite and random amplified microsatellite polymorphism markers.

    PubMed

    Rai, Ved Prakash; Kumar, Rajesh; Kumar, Sanjay; Rai, Ashutosh; Kumar, Sanjeet; Singh, Major; Singh, Sheo Pratap; Rai, Awadesh Bahadur; Paliwal, Rajneesh

    2013-10-01

    A sound knowledge of the genetic diversity among germplasm is vital for strategic germplasm collection, maintenance, conservation and utilisation. Genomic simple sequence repeats (SSRs) and random amplified microsatellite polymorphism (RAMPO) markers were used to analyse diversity and relationships among 48 pepper (Capsicum spp.) genotypes originating from nine countries. These genotypes covered 4 species including 13 germplasm accessions, 30 improved lines of 4 domesticated species and 5 landraces derived from natural interspecific crosses. Out of 106 SSR markers, 25 polymorphic SSR markers (24 %) detected a total of 76 alleles (average, 3.04; range, 2-5). The average polymorphic information content (PIC) was 0.69 (range, 0.29-0.92). Seventeen RAMPO markers produced 87 polymorphic fragments with average PIC of 0.63 (range, 0.44-0.81). Dendrograms based on SSRs and RAMPOs generated two clusters. All 38 Capsicum annuum genotypes and an interspecific landrace clustered together, whereas nine non-annuum (three Capsicum frutescens, one Capsicum chinense, one Capsicum baccatum and four interspecific landraces) genotypes clustered separately. Genetic variation within non-annuum genotypes was greater than the C. annuum genotypes. Distinctness of interspecific derivative landraces grown in northeast India was validated; natural crossing between sympatric Capsicum species has been proposed as the mechanism of their origin. PMID:24431527

  16. Comparative Analysis of Disease-Linked Single Nucleotide Polymorphic Markers from Brassica rapa for Their Applicability to Brassica oleracea

    PubMed Central

    Cho, Young-Il; Ahn, Yul-Kyun; Tripathi, Swati; Kim, Jeong-Ho; Lee, Hye-Eun; Kim, Do-Sun

    2015-01-01

    Numerous studies using single nucleotide polymorphisms (SNPs) have been conducted in humans, and other animals, and in major crops, including rice, soybean, and Chinese cabbage. However, the number of SNP studies in cabbage is limited. In this present study, we evaluated whether 7,645 SNPs previously identified as molecular markers linked to disease resistance in the Brassica rapa genome could be applied to B. oleracea. In a BLAST analysis using the SNP sequences of B. rapa and B. oleracea genomic sequence data registered in the NCBI database, 256 genes for which SNPs had been identified in B. rapa were found in B. oleracea. These genes were classified into three functional groups: molecular function (64 genes), biological process (96 genes), and cellular component (96 genes). A total of 693 SNP markers, including 145 SNP markers [BRH—developed from the B. rapa genome for high-resolution melt (HRM) analysis], 425 SNP markers (BRP—based on the B. rapa genome that could be applied to B. oleracea), and 123 new SNP markers (BRS—derived from BRP and designed for HRM analysis), were investigated for their ability to amplify sequences from cabbage genomic DNA. In total, 425 of the SNP markers (BRP-based on B. rapa genome), selected from 7,645 SNPs, were successfully applied to B. oleracea. Using PCR, 108 of 145 BRH (74.5%), 415 of 425 BRP (97.6%), and 118 of 123 BRS (95.9%) showed amplification, suggesting that it is possible to apply SNP markers developed based on the B. rapa genome to B. oleracea. These results provide valuable information that can be utilized in cabbage genetics and breeding programs using molecular markers derived from other Brassica species. PMID:25790283

  17. Automated SNP detection from a large collection of white spruce expressed sequences: contributing factors and approaches for the categorization of SNPs

    PubMed Central

    Pavy, Nathalie; Parsons, Lee S; Paule, Charles; MacKay, John; Bousquet, Jean

    2006-01-01

    Background High-throughput genotyping technologies represent a highly efficient way to accelerate genetic mapping and enable association studies. As a first step toward this goal, we aimed to develop a resource of candidate Single Nucleotide Polymorphisms (SNP) in white spruce (Picea glauca [Moench] Voss), a softwood tree of major economic importance. Results A white spruce SNP resource encompassing 12,264 SNPs was constructed from a set of 6,459 contigs derived from Expressed Sequence Tags (EST) and by using the bayesian-based statistical software PolyBayes. Several parameters influencing the SNP prediction were analysed including the a priori expected polymorphism, the probability score (PSNP), and the contig depth and length. SNP detection in 3' and 5' reads from the same clones revealed a level of inconsistency between overlapping sequences as low as 1%. A subset of 245 predicted SNPs were verified through the independent resequencing of genomic DNA of a genotype also used to prepare cDNA libraries. The validation rate reached a maximum of 85% for SNPs predicted with either PSNP ≥ 0.95 or ≥ 0.99. A total of 9,310 SNPs were detected by using PSNP ≥ 0.95 as a criterion. The SNPs were distributed among 3,590 contigs encompassing an array of broad functional categories, with an overall frequency of 1 SNP per 700 nucleotide sites. Experimental and statistical approaches were used to evaluate the proportion of paralogous SNPs, with estimates in the range of 8 to 12%. The 3,789 coding SNPs identified through coding region annotation and ORF prediction, were distributed into 39% nonsynonymous and 61% synonymous substitutions. Overall, there were 0.9 SNP per 1,000 nonsynonymous sites and 5.2 SNPs per 1,000 synonymous sites, for a genome-wide nonsynonymous to synonymous substitution rate ratio (Ka/Ks) of 0.17. Conclusion We integrated the SNP data in the ForestTreeDB database along with functional annotations to provide a tool facilitating the choice of candidate

  18. RAD sequencing yields a high success rate for westslope cutthroat and rainbow trout species-diagnostic SNP assays

    USGS Publications Warehouse

    Stephen J. Amish; Paul A. Hohenlohe; Sally Painter; Robb F. Leary; Muhlfeld, Clint C.; Fred W. Allendorf; Luikart, Gordon

    2012-01-01

    Hybridization with introduced rainbow trout threatens most native westslope cutthroat trout populations. Understanding the genetic effects of hybridization and introgression requires a large set of high-throughput, diagnostic genetic markers to inform conservation and management. Recently, we identified several thousand candidate single-nucleotide polymorphism (SNP) markers based on RAD sequencing of 11 westslope cutthroat trout and 13 rainbow trout individuals. Here, we used flanking sequence for 56 of these candidate SNP markers to design high-throughput genotyping assays. We validated the assays on a total of 92 individuals from 22 populations and seven hatchery strains. Forty-six assays (82%) amplified consistently and allowed easy identification of westslope cutthroat and rainbow trout alleles as well as heterozygote controls. The 46 SNPs will provide high power for early detection of population admixture and improved identification of hybrid and nonhybridized individuals. This technique shows promise as a very low-cost, reliable and relatively rapid method for developing and testing SNP markers for nonmodel organisms with limited genomic resources.

  19. Prioritizing sequence polymorphisms for potential association with phenotype

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The millions of SNP, insertions and deletions revealed by next generation sequencing (NGS), are certain to include polymorphisms responsible for phenotypic variation. Distinguishing causal from benign variants may allow genomic predictions that are robust across populations. While variants underly...

  20. Single Nucleotide Polymorphisms for Pig Identification and Parentage Exclusion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Single nucleotide polymorphisms have become an important type of marker for commercial diagnostic and parentage genotyping applications as automated genotyping systems have been developed that yield accurate genotypes. Unfortunately, a large number of highly informative public SNP markers tested in ...

  1. Differentiation of four strains of Chinese soft-shelled turtle (Pelodiscus sinensis) based on high-resolution melting analysis of single nucleotide polymorphism sites in mitochondrial DNA.

    PubMed

    Zhang, H Q; Zhang, C; Xu, X J; Zhu, J J; He, Z Y; Shao, J Z

    2015-01-01

    The Chinese soft-shelled turtle (Pelodiscus sinensis) has been one of the most economically important aquatic animals in China for thousands of years, and several breeding strains have been formed. Since the morphological characteristics of some strains are similar, a rapid and accurate molecular method to differentiate between strains is required. In this study, partial sequences of mitochondrial DNA from four turtle strains, Taihu Lake Strain, Taiwan Strain, Japanese Strain, and Yellow River Strain, were amplified and sequenced based on selected strain-specific single nucleotide polymorphism (SNP) sites. The corresponding primers were designed and a high-resolution melting (HRM) technique was employed for genotyping these SNPs. The results indicated that a total of seven SNPs can be detected by HRM. Among these SNPs, one can be used for identifying the Taihu Lake Strain, one for the Japanese Strain, two for the Taiwan Strain, and three for the Yellow River Strain. This method is rapid and convenient, which offers technical support for strain identification and selective breeding in Chinese soft-shelled turtles. PMID:26535627

  2. Plastid DNA sequencing and nuclear SNP genotyping help resolve the puzzle of central American Platanus

    PubMed Central

    De Castro, Olga; Di Maio, Antonietta; Lozada García, José Armando; Piacenti, Danilo; Vázquez-Torres, Mario; De Luca, Paolo

    2013-01-01

    Background and Aims Recent research on the history of Platanus reveals that hybridization phenomena occurred in the central American species. This study has two goals: to help resolve the evolutive puzzle of central American Platanus, and to test the potential of real-time polymerase chain reaction (PCR) for detecting ancient hybridization. Methods Sequencing of a uniparental plastid DNA marker [psbA-trnH(GUG) intergenic spacer] and qualitative and quantitative single nucleotide polymorphism (SNP) genotyping of biparental nuclear ribosomal DNA (nrDNA) markers [LEAFY intron 2 (LFY-i2) and internal transcribed spacer 2 (ITS2)] were used. Key Results Based on the SNP genotyping results, several Platanus accessions show the presence of hybridization/introgression, including some accessions of P. rzedowskii and of P. mexicana var. interior and one of P. mexicana var. mexicana from Oaxaca (= P. oaxacana). Based on haplotype analyses of the psbA-trnH spacer, five haplotypes were detected. The most common of these is present in taxa belonging to P. orientalis, P. racemosa sensu lato, some accessions of P. occidentalis sensu stricto (s.s.) from Texas, P. occidentalis var. palmeri, P. mexicana s.s. and P. rzedowskii. This is highly relevant to genetic relationships with the haplotypes present in P. occidentalis s.s. and P. mexicana var. interior. Conclusions Hybridization and introgression events between lineages ancestral to modern central and eastern North American Platanus species occurred. Plastid haplotypes and qualitative and quantitative SNP genotyping provide information critical for understanding the complex history of Mexican Platanus. Compared with the usual molecular techniques of sub-cloning, sequencing and genotyping, real-time PCR assay is a quick and sensitive technique for analysing complex evolutionary patterns. PMID:23798602

  3. Single Nucleotide Polymorphism Mapping Using Genome-Wide Unique Sequences

    PubMed Central

    Chen, Leslie Y.Y.; Lu, Szu-Hsien; Shih, Edward S.C.; Hwang, Ming-Jing

    2002-01-01

    As more and more genomic DNAs are sequenced to characterize human genetic variations, the demand for a very fast and accurate method to genomically position these DNA sequences is high. We have developed a new mapping method that does not require sequence alignment. In this method, we first identified DNA fragments of 15 bp in length that are unique in the human genome and then used them to position single nucleotide polymorphism (SNP) sequences. By use of four desktop personal computers with AMD K7 (1 GHz) processors, our new method mapped more than 1.6 million SNP sequences in 20 hr and achieved a very good agreement with mapping results from alignment-based methods. PMID:12097348

  4. Association of COL2A1 Gene Polymorphism with Degenerative Lumbar Scoliosis

    PubMed Central

    Hwang, Dae Woo; Lee, Sang Hoon; Kim, Jung Youn; Kim, Dong Hwan

    2014-01-01

    Background Degenerative lumbar scoliosis (DLS) progresses with aging after 50-60 years, and the genetic association of DLS remains largely unclear. In this study, the genetic association between collagen type II alpha 1 (COL2A1) gene and DLS was investigated. Methods COL2A1 gene polymorphism was investigated in DLS subjects compared to healthy controls to investigate the possibility of its association with COL2A1 gene. Based on a single nucleotide polymorphism (SNP) database, SNP (rs2276454) in COL2A1 were selected and genotyped using direct sequencing in 51 patients with DLS and 235 healthy controls. The SNP effects were analyzed using three models of codominant, dominant, and recessive. Logistic regression models were calculated for odds ratios (ORs) with 95% confidence intervals (CIs) and corresponding p-values, controlling age and gender as co-variables. Results SNP (rs2276454) in COL2A1 was significantly associated with the degenerative lumbar scoliosis in the codominant (OR, 1.90; 95% CI, 1.17 to 3.10; p = 0.008) and dominant models (OR, 3.58; 95% CI, 1.59 to 9.29; p = 0.001). Conclusions The results suggest that COL2A1 is associated with the risk of DLS in Korean population. PMID:25436060

  5. [Application of single nucleotide polymorphism in crop genetics and improvement].

    PubMed

    Du, Chun-Fang; Liu, Hui-Min; Li, Run-Zhi; Li, Peng-Bo; Ren, Zhi-Qiang

    2003-11-01

    Single nucleotide polymorphism(SNP) is the most common type of sequence difference between alleles, which can be used as a kind of high-throughput genetic marker. Several different routes have been developed to discover and identify SNP. These include the direct sequencing of PCR amplicons, electronic SNP(eSNP) and so on. SNP assays have been made in many crop species such as maize and soybean. The elite germplasm of some crops have been narrowed in genetic diversity, increasing the amount of linkage disequilibrium (LD) present and facilitating the association of SNP haplotypes at candidate gene loci with phenotypes. SNP analysis has been broadly used in the field of plant gene mapping, integration of genetic and physical maps, DNA marker-assisted breeding and functional genomics. PMID:15639972

  6. Development and characterization of polymorphic microRNA-based microsatellite markers in Nelumbo nucifera (Nelumbonaceae)1

    PubMed Central

    Wang, Xiaolei; Gui, Songtao; Pan, Lei; Hu, Jihong; Ding, Yi

    2016-01-01

    Premise of the study: Polymorphic microRNA (miRNA)–based microsatellite markers were developed to investigate the genetic diversity and population structure of Nelumbo nucifera (Nelumbonaceae). Methods and Results: A total of 485 miRNA-based microsatellites were found from the genomic DNA sequences of N. nucifera. After several rounds of screening, 21 primer pairs flanking di-, tri-, or pentanucleotide repeats were identified that revealed high levels of genetic diversity in four populations with two to five alleles per locus. The observed and expected heterozygosity per locus ranged from 0.000 to 1.000 and from 0.000 to 0.803, respectively. Conclusions: The polymorphic microsatellite markers will be useful for studying the genetic diversity and population structure of N. nucifera. PMID:26819861

  7. Prediction of a time-to-event trait using genome wide SNP data

    PubMed Central

    2013-01-01

    Background A popular objective of many high-throughput genome projects is to discover various genomic markers associated with traits and develop statistical models to predict traits of future patients based on marker values. Results In this paper, we present a prediction method for time-to-event traits using genome-wide single-nucleotide polymorphisms (SNPs). We also propose a MaxTest associating between a time-to-event trait and a SNP accounting for its possible genetic models. The proposed MaxTest can help screen out nonprognostic SNPs and identify genetic models of prognostic SNPs. The performance of the proposed method is evaluated through simulations. Conclusions In conjunction with the MaxTest, the proposed method provides more parsimonious prediction models but includes more prognostic SNPs than some naive prediction methods. The proposed method is demonstrated with real GWAS data. PMID:23418752

  8. Obesity-related known and candidate SNP markers can significantly change affinity of TATA-binding protein for human gene promoters

    PubMed Central

    2015-01-01

    Background Obesity affects quality of life and life expectancy and is associated with cardiovascular disorders, cancer, diabetes, reproductive disorders in women, prostate diseases in men, and congenital anomalies in children. The use of single nucleotide polymorphism (SNP) markers of diseases and drug responses (i.e., significant differences of personal genomes of patients from the reference human genome) can help physicians to improve treatment. Clinical research can validate SNP markers via genotyping of patients and demonstration that SNP alleles are significantly more frequent in patients than in healthy people. The search for biomedical SNP markers of interest can be accelerated by computer-based analysis of hundreds of millions of SNPs in the 1000 Genomes project because of selection of the most meaningful candidate SNP markers and elimination of neutral SNPs. Results We cross-validated the output of two computer-based methods: DNA sequence analysis using Web service SNP_TATA_Comparator and keyword search for articles on comorbidities of obesity. Near the sites binding to TATA-binding protein (TBP) in human gene promoters, we found 22 obesity-related candidate SNP markers, including rs10895068 (male breast cancer in obesity); rs35036378 (reduced risk of obesity after ovariectomy); rs201739205 (reduced risk of obesity-related cancers due to weight loss by diet/exercise in obese postmenopausal women); rs183433761 (obesity resistance during a high-fat diet); rs367732974 and rs549591993 (both: cardiovascular complications in obese patients with type 2 diabetes mellitus); rs200487063 and rs34104384 (both: obesity-caused hypertension); rs35518301, rs72661131, and rs562962093 (all: obesity); and rs397509430, rs33980857, rs34598529, rs33931746, rs33981098, rs34500389, rs63750953, rs281864525, rs35518301, and rs34166473 (all: chronic inflammation in comorbidities of obesity). Using an electrophoretic mobility shift assay under nonequilibrium conditions, we

  9. A method for single nucleotide polymorphism selection for parentage assessment in goats.

    PubMed

    Talenti, A; Nicolazzi, E L; Chessa, S; Frattini, S; Moretti, R; Coizet, B; Nicoloso, L; Colli, L; Pagnacco, G; Stella, A; Ajmone-Marsan, P; Ptak, G; Crepaldi, P

    2016-05-01

    Accurate pedigrees are essential to optimize genetic improvement and conservation of animal genetic resources. In goats, the use of mating groups and kidding management procedures hamper the identification of parentage. Small panels of single nucleotide polymorphisms (SNP) have been proposed in other species to substitute microsatellites for parentage assessment. Using data from the current GoatSNP50 chip, we developed a new 3-step procedure to identify a low-density SNP panel for highly accurate parentage assessment. Methodologies for SNP selection used in other species are less suitable in the goat because of uncertainties in the genome assembly. The procedure developed in this study is based on parent-offspring identification and on estimation of Mendelian errors, followed by canonical discriminant analysis identification and stepwise regression reduction. Starting from a reference sample of 109 Alpine goats with known pedigree relationships, we first identified a panel of 200 SNP that was further reduced to 2 final panels of 130 and 114 SNP with random coincidental match inclusion of 1.51×10(-57) and 2.94×10(-34), respectively. In our reference data set, all panels correctly identified all parent-offspring combinations, revealing a 40% pedigree error rate in the information provided by breeders. All reference trios were confirmed by official tests based on microsatellites. Panels were also tested on Saanen and Teramana breeds. Although the testing on a larger set of breeds in the reference population is still needed to validate these results, our findings suggest that our procedure could identify SNP panels for accurate parentage assessment in goats or in other species with unreliable marker positioning. PMID:26971153

  10. Crystallinity-based product design: Utilizing the polymorphism of isotactic PP homo- and copolymers

    NASA Astrophysics Data System (ADS)

    Gahleitner, Markus; Mileva, Daniela; Androsch, René; Gloger, Dietrich; Tranchida, Davide; Sandholzer, Martina; Doshev, Petar

    2015-12-01

    The polymorphism of isotactic polypropylene (iPP) in combination with the strong response of this polymer to nucleation can be utilized for expanding the application range of this versatile polymer. Based on three "case studies" related to β-iPP pressure pipes, ethylene-propylene (EP) random copolymers for thin-wall injection molding and sterilization resistance of cast films we demonstrate ways of combining polymer composition, nucleation and process settings to achieve the desired application performance.

  11. Imputing amino acid polymorphisms in human leukocyte antigens.

    PubMed

    Jia, Xiaoming; Han, Buhm; Onengut-Gumuscu, Suna; Chen, Wei-Min; Concannon, Patrick J; Rich, Stephen S; Raychaudhuri, Soumya; de Bakker, Paul I W

    2013-01-01

    DNA sequence variation within human leukocyte antigen (HLA) genes mediate susceptibility to a wide range of human diseases. The complex genetic structure of the major histocompatibility complex (MHC) makes it difficult, however, to collect genotyping data in large cohorts. Long-range linkage disequilibrium between HLA loci and SNP markers across the major histocompatibility complex (MHC) region offers an alternative approach through imputation to interrogate HLA variation in existing GWAS data sets. Here we describe a computational strategy, SNP2HLA, to impute classical alleles and amino acid polymorphisms at class I (HLA-A, -B, -C) and class II (-DPA1, -DPB1, -DQA1, -DQB1, and -DRB1) loci. To characterize performance of SNP2HLA, we constructed two European ancestry reference panels, one based on data collected in HapMap-CEPH pedigrees (90 individuals) and another based on data collected by the Type 1 Diabetes Genetics Consortium (T1DGC, 5,225 individuals). We imputed HLA alleles in an independent data set from the British 1958 Birth Cohort (N = 918) with gold standard four-digit HLA types and SNPs genotyped using the Affymetrix GeneChip 500 K and Illumina Immunochip microarrays. We demonstrate that the sample size of the reference panel, rather than SNP density of the genotyping platform, is critical to achieve high imputation accuracy. Using the larger T1DGC reference panel, the average accuracy at four-digit resolution is 94.7% using the low-density Affymetrix GeneChip 500 K, and 96.7% using the high-density Illumina Immunochip. For amino acid polymorphisms within HLA genes, we achieve 98.6% and 99.3% accuracy using the Affymetrix GeneChip 500 K and Illumina Immunochip, respectively. Finally, we demonstrate how imputation and association testing at amino acid resolution can facilitate fine-mapping of primary MHC association signals, giving a specific example from type 1 diabetes. PMID:23762245

  12. A high-throughput SNP array in the amphidiploid species Brassica napus shows diversity in resistance genes.

    PubMed

    Dalton-Morgan, Jessica; Hayward, Alice; Alamery, Salman; Tollenaere, Reece; Mason, Annaliese S; Campbell, Emma; Patel, Dhwani; Lorenc, Michał T; Yi, Bin; Long, Yan; Meng, Jinling; Raman, Rosy; Raman, Harsh; Lawley, Cindy; Edwards, David; Batley, Jacqueline

    2014-12-01

    Single-nucleotide polymorphisms (SNPs)are molecular markers based on nucleotide variation and can be used for genotyping assays across populations and to track genomic inheritance. SNPs offer a comprehensive genotyping alternative to whole-genome sequencing for both agricultural and research purposes including molecular breeding and diagnostics, genome evolution and genetic diversity analyses, genetic mapping, and trait association studies. Here genomic SNPs were discovered between four cultivars of the important amphidiploid oilseed species Brassica napus and used to develop a B. napus Infinium™ array containing 5,306 SNPs randomly dispersed across the genome. Assay success was high, with >94 % of these producing a reproducible, polymorphic genotype in the 1,070 samples screened. Although the assay was designed to B. napus, successful SNP amplification was achieved in the B. napus progenitor species, Brassica rapa and Brassica oleracea, and to a lesser extent in the related species Brassica nigra. Phylogenetic analysis was consistent with the expected relationships between B. napus individuals. This study presents an efficient custom SNP assay development pipeline in the complex polyploid Brassica genome and demonstrates the utility of the array for high-throughput genotyping in a number of related Brassica species. It also demonstrates the utility of this assay in genotyping resistance genes on chromosome A7, which segregate amongst the 1,070 samples. PMID:25147024

  13. Combined use of a new SNP-based assay and multilocus SSR markers to assess genetic diversity of Xylella fastidiosa subsp. pauca infecting citrus and coffee plants.

    PubMed

    Montes-Borrego, Miguel; Lopes, Joao R S; Jiménez-Díaz, Rafael M; Landa, Blanca B

    2015-03-01

    Two haplotypes of Xylella fastidiosa subsp. pauca (Xfp) that correlated with their host of origin were identified in a collection of 90 isolates infecting citrus and coffee plants in Brazil, based on a single-nucleotide polymorphism in the gyrB sequence. A new single-nucleotide primer extension (SNuPE) protocol was designed for rapid identification of Xfp according to the host source. The protocol proved to be robust for the prediction of the Xfp host source in blind tests using DNA from cultures of the bacterium, infected plants, and insect vectors allowed to feed on Xfp-infected citrus plants. AMOVA and STRUCTURE analyses of microsatellite data separated most Xfp populations on the basis of their host source, indicating that they were genetically distinct. The combined use of the SNaPshot protocol and three previously developed multilocus SSR markers showed that two haplotypes and distinct isolates of Xfp infect citrus and coffee in Brazil and that multiple, genetically different isolates can be present in a single orchard or infect a single tree. This combined approach will be very useful in studies of the epidemiology of Xfp-induced diseases, host specificity of bacterial genotypes, the occurrence of Xfp host jumping, vector feeding habits, etc., in economically important cultivated plants or weed host reservoirs of Xfp in Brazil and elsewhere. PMID:26415663

  14. High-throughput single nucleotide polymorphism genotyping for breeding applications in rice using the BeadXpress platform

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multiplexed single nucleotide polymorphism (SNP) markers have the potential to increase the speed and cost-effectiveness of genotyping, provided that an optimal SNP density is used for each application. To test the efficiency of multiplexed SNP genotyping for diversity, mapping and breeding applicat...

  15. Selection of single nucleotide polymorphisms and genotype quality for genomic prediction of genetic merit in dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A process to prepare high-density genotypic data for use in genomic prediction of genetic merit was developed. Marker genotypes from over 51,000 single nucleotide polymorphisms (SNP) were generated for 3,139 Holstein bulls on the Illumina Bovine SNP50™ chip. The SNP were categorized by minor allele ...

  16. PPLine: An Automated Pipeline for SNP, SAP, and Splice Variant Detection in the Context of Proteogenomics.

    PubMed

    Krasnov, George Sergeevich; Dmitriev, Alexey Alexandrovich; Kudryavtseva, Anna Viktorovna; Shargunov, Alexander Valerievich; Karpov, Dmitry Sergeevich; Uroshlev, Leonid Andreevich; Melnikova, Natalya Vladimirovna; Blinov, Vladimir Mikhailovich; Poverennaya, Ekaterina Vladimirovna; Archakov, Alexander Ivanovich; Lisitsa, Andrey Valerievich; Ponomarenko, Elena Alexandrovna

    2015-09-01

    The fundamental mission of the Chromosome-Centric Human Proteome Project (C-HPP) is the research of human proteome diversity, including rare variants. Liver tissues, HepG2 cells, and plasma were selected as one of the major objects for C-HPP studies. The proteogenomic approach, a recently introduced technique, is a powerful method for predicting and validating proteoforms coming from alternative splicing, mutations, and transcript editing. We developed PPLine, a Python-based proteogenomic pipeline providing automated single-amino-acid polymorphism (SAP), indel, and alternative-spliced-variants discovery based on raw transcriptome and exome sequence data, single-nucleotide polymorphism (SNP) annotation and filtration, and the prediction of proteotypic peptides (available at https://sourceforge.net/projects/ppline). In this work, we performed deep transcriptome sequencing of HepG2 cells and liver tissues using two platforms: Illumina HiSeq and Applied Biosystems SOLiD. Using PPLine, we revealed 7756 SAP and indels for HepG2 cells and liver (including 659 variants nonannotated in dbSNP). We found 17 indels in transcripts associated with the translation of alternate reading frames (ARF) longer than 300 bp. The ARF products of two genes, SLMO1 and TMEM8A, demonstrate signatures of caspase-binding domain and Gcn5-related N-acetyltransferase. Alternative splicing analysis predicted novel proteoforms encoded by 203 (liver) and 475 (HepG2) genes according to both Illumina and SOLiD data. The results of the present work represent a basis for subsequent proteomic studies by the C-HPP consortium. PMID:26147802

  17. Making a chocolate chip: development and evaluation of a 6K SNP array for Theobroma cacao.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Theobroma cacao, the key ingredient in chocolate production, is one of the world's most important tree fruit crops, with ~4,000,000 metric tons produced across 50 countries. To move towards gene discovery and marker-assisted breeding in cacao, a single-nucleotide polymorphism (SNP) identification pr...

  18. Association mapping of resistance to leaf rust in emmer wheat using high throughput SNP markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emmer wheat (Triticum turgidum L. subsp. dicoccum) is known to be a useful source of genes for many desirable characters for improvement of modern cultivated wheat. Recently, a panel of 181 emmer wheat accessions has been genotyped with wheat 9K SNP (single nucleotide polymorphism) markers and exte...

  19. Development of gene-tagged SNP markers for gland morphogenesis in cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton (Gossypium spp.) plants, including cottonseed, have small, pigmented glands containing gossypol and other terpenoid compounds that are toxic to humans and non-ruminant animals. Single nucleotide polymorphism (SNP) markers involved in gland morphogenesis are useful for the discovery of candid...

  20. Optimal design of low-density SNP arrays for genomic prediction: algorithm and applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low-density (LD) single nucleotide polymorphism (SNP) arrays provide a cost-effective solution for genomic prediction and selection, but algorithms and computational tools are needed for their optimal design. A multiple-objective, local optimization (MOLO) algorithm was developed for design of optim...

  1. Development and Characterization of a High Density SNP Genotyping Assay for Cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The success of genomewide association (GWA) studies for the detection of sequence variation affecting complex traits in human has spurred interest in the use of large-scale high-density single nucleotide polymorphism (SNP) genotyping for the identification of quantitative trait loci (QTL) and for ma...

  2. The development and characterization of a 57K SNP Chip for rainbow trout

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper we describe the development and characterization of the first high density SNP chip for rainbow trout. The chip included 57,500 putative SNPs, of which 49,500 (86%) were validated as high quality and polymorphic in our validation panel of 960 rainbow trout samples. This array is compa...

  3. Construction and application of a bovine high-density SNP assay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine genomics has entered a new era and has been transformed by the availability of the whole genome sequence data. An additional resource currently under development is a 60,000 single nucleotide polymorphism (SNP) array that will soon be made commercially available. Targetted content for this SN...

  4. SNP analysis of AMY2 and CTSL genes in Litopenaeus vannamei and Penaeus monodon shrimp.

    PubMed

    Glenn, K L; Grapes, L; Suwanasopee, T; Harris, D L; Li, Y; Wilson, K; Rothschild, M F

    2005-06-01

    Genetic studies in shrimp have focused on disease, with production traits such as growth left unexamined. Two shrimp species, Litopenaeus vannamei and Penaeus monodon, which represent the majority of US shrimp imports, were selected for single nucleotide polymorphism (SNP) discovery in alpha-amylase (AMY2) and cathepsin-l (CTSL), both candidate genes for growth. In L. vannamei, four SNPs were found in AMY2 and one SNP was found in CTSL. In P. monodon, one SNP was identified in CTSL. The CTSL gene was mapped to linkage group 28 of P. monodon using the female map developed with the Australian P. monodon mapping population. Association analyses for the AMY2 and CTSL genes with body weight (BW) were performed in two L. vannamei populations. While neither gene was found to be significantly associated with BW in these populations, there was a trend in one population towards higher BW for allele G of CTSL SNP C681G. PMID:15932404

  5. Interim report on updated microarray probes for the LLNL Burkholderia pseudomallei SNP array

    SciTech Connect

    Gardner, S; Jaing, C

    2012-03-27

    The overall goal of this project is to forensically characterize 100 unknown Burkholderia isolates in the US-Australia collaboration. We will identify genome-wide single nucleotide polymorphisms (SNPs) from B. pseudomallei and near neighbor species including B. mallei, B. thailandensis and B. oklahomensis. We will design microarray probes to detect these SNP markers and analyze 100 Burkholderia genomic DNAs extracted from environmental, clinical and near neighbor isolates from Australian collaborators on the Burkholderia SNP microarray. We will analyze the microarray genotyping results to characterize the genetic diversity of these new isolates and triage the samples for whole genome sequencing. In this interim report, we described the SNP analysis and the microarray probe design for the Burkholderia SNP microarray.

  6. Gene-based microsatellites for cassava (Manihot esculenta Crantz): prevalence, polymorphisms, and cross-taxa utility

    PubMed Central

    Raji, Adebola AJ; Anderson, James V; Kolade, Olufisayo A; Ugwu, Chike D; Dixon, Alfred GO; Ingelbrecht, Ivan L

    2009-01-01

    Background Cassava (Manihot esculenta Crantz), a starchy root crop grown in tropical and subtropical climates, is the sixth most important crop in the world after wheat, rice, maize, potato and barley. The repertoire of simple sequence repeat (SSR) markers for cassava is limited and warrants a need for a larger number of polymorphic SSRs for germplasm characterization and breeding applications. Results A total of 846 putative microsatellites were identified in silico from an 8,577 cassava unigene set with an average density of one SSR every 7 kb. One hundred and ninety-two candidate SSRs were screened for polymorphism among a panel of cassava cultivars from Africa, Latin America and Asia, four wild Manihot species as well as two other important taxa in the Euphorbiaceae, leafy spurge (Euphorbia esula) and castor bean (Ricinus communis). Of 168 markers with clean amplification products, 124 (73.8%) displayed polymorphism based on high resolution agarose gels. Of 85 EST-SSR markers screened, 80 (94.1%) amplified alleles from one or more wild species (M epruinosa, M glaziovii, M brachyandra, M tripartita) whereas 13 (15.3%) amplified alleles from castor bean and 9 (10.6%) amplified alleles from leafy spurge; hence nearly all markers were transferable to wild relatives of M esculenta while only a fraction was transferable to the more distantly related taxa. In a subset of 20 EST-SSRs assessed by fluorescence-based genotyping the number of alleles per locus ranged from 2 to 10 with an average of 4.55 per locus. These markers had a polymorphism information content (PIC) from 0.19 to 0.75 with an average value of 0.55 and showed genetic relationships consistent with existing information on these genotypes. Conclusion A set of 124 new, unique polymorphic EST-SSRs was developed and characterized which extends the repertoire of SSR markers for cultivated cassava and its wild relatives. The markers show high PIC values and therefore will be useful for cultivar identification

  7. Selecting a Maximally Informative Set of Single-Nucleotide Polymorphisms for Association Analyses Using Linkage Disequilibrium

    PubMed Central

    Carlson, Christopher S.; Eberle, Michael A.; Rieder, Mark J.; Yi, Qian; Kruglyak, Leonid; Nickerson, Deborah A.

    2004-01-01

    Common genetic polymorphisms may explain a portion of the heritable risk for common diseases. Within candidate genes, the number of common polymorphisms is finite, but direct assay of all existing common polymorphism is inefficient, because genotypes at many of these sites are strongly correlated. Thus, it is not necessary to assay all common variants if the patterns of allelic association between common variants can be described. We have developed an algorithm to select the maximally informative set of common single-nucleotide polymorphisms (tagSNPs) to assay in candidate-gene association studies, such that all known common polymorphisms either are directly assayed or exceed a threshold level of association with a tagSNP. The algorithm is based on the r2 linkage disequilibrium (LD) statistic, because r2 is directly related to statistical power to detect disease associations with unassayed sites. We show that, at a relatively stringent r2 threshold (r2>0.8), the LD-selected tagSNPs resolve >80% of all haplotypes across a set of 100 candidate genes, regardless of recombination, and tag specific haplotypes and clades of related haplotypes in nonrecombinant regions. Thus, if the patterns of common variation are described for a candidate gene, analysis of the tagSNP set can comprehensively interrogate for main effects from common functional variation. We demonstrate that, although common variation tends to be shared between populations, tagSNPs should be selected separately for populations with different ancestries. PMID:14681826

  8. A functional HOTAIR rs12826786 C>T polymorphism is associated with breast cancer susceptibility and poor clinicopathological characteristics in a Turkish population: a hospital-based case-control study.

    PubMed

    Bayram, Süleyman; Sümbül, Ahmet Taner; Dadaş, Erdoğan

    2016-04-01

    Hox transcript antisense intergenic RNA (HOTAIR), a long non-coding RNA (lncRNA), is pervasively overexpressed and correlated with tumor invasion, progression, metastasis, and poor prognosis in various human cancers including breast cancer (BC) that plays a role as an oncogenic molecule. A common functional single-nucleotide polymorphism (SNP) (rs12826786 C>T) at the HOTAIR promoter has been reported to influence HOTAIR expression and gastric adenocarcinoma susceptibility, but relation of HOTAIR rs12826786 C>T polymorphism with BC susceptibility and clinicopathological characteristics has yet to be reported. To explore the association of the HOTAIR rs12826786 C>T polymorphism with the risk of BC in a Turkish population, a hospital-based case-control study was carried out consisting of 123 BC patients and 122 age-matched healthy controls. HOTAIR rs12826786 C>T polymorphism was determined by real-time polymerase chain reaction (PCR) using TaqMan assay. We found that women carrying TT genotype of HOTAIR rs12826786 C>T polymorphism had an increased risk of developing BC in both codominant (odds ratio (OR) = 2.24, 95 % confidence interval (CI) 1.05-4.81, P = 0.02) and recessive (OR = 2.49, 95 % CI 1.25-4.97, P = 0.008) inheritance models. Moreover, TT genotype of HOTAIR rs12826786 C>T polymorphism was significantly related with multiple clinicopathological characteristics concerned with worse BC progression such as advanced TNM stage (III and IV), larger tumor size (T3 and T4), and distant metastasis (M1), as well as poor histological grade (III) (P < 0.05). Because of our results put forward for the first time that TT genotype of HOTAIR rs12826786 C>T polymorphism might play crucial roles in genetic susceptibility and poor prognosis for BC in Turkish population, further independent studies are needed to confirm our results in a larger series, as well as in patients of distinct populations. PMID:26577852

  9. A Germline Polymorphism of DNA Polymerase Beta Induces Genomic Instability and Cellular Transformation

    PubMed Central

    Keh, Agnes; Sweasy, Joann B.

    2012-01-01

    Several germline single nucleotide polymorphisms (SNPs) have been identified in the POLB gene, but little is known about their cellular and biochemical impact. DNA Polymerase β (Pol β), encoded by the POLB gene, is the main gap-filling polymerase involved in base excision repair (BER), a pathway that protects the genome from the consequences of oxidative DNA damage. In this study we tested the hypothesis that expression of the POLB germline coding SNP (rs3136797) in mammalian cells could induce a cancerous phenotype. Expression of this SNP in both human and mouse cells induced double-strand breaks, chromosomal aberrations, and cellular transformation. Following treatment with an alkylating agent, cells expressing this coding SNP accumulated BER intermediate substrates, including single-strand and double-strand breaks. The rs3136797 SNP encodes the P242R variant Pol β protein and biochemical analysis showed that P242R protein had a slower catalytic rate than WT, although P242R binds DNA similarly to WT. Our results suggest that people who carry the rs3136797 germline SNP may be at an increased risk for cancer susceptibility. PMID:23144635

  10. Performance of different SNP panels for parentage testing in two East Asian cattle breeds.

    PubMed

    Strucken, E M; Gudex, B; Ferdosi, M H; Lee, H K; Song, K D; Gibson, J P; Kelly, M; Piper, E K; Porto-Neto, L R; Lee, S H; Gondro, C

    2014-08-01

    The International Society for Animal Genetics (ISAG) proposed a panel of single nucleotide polymorphisms (SNPs) for parentage testing in cattle (a core panel of 100 SNPs and an additional list of 100 SNPs). However, markers specific to East Asian taurine cattle breeds were not included, and no information is available as to whether the ISAG panel performs adequately for these breeds. We tested ISAG's core (100 SNP) and full (200 SNP) panels on two East Asian taurine breeds: the Korean Hanwoo and the Japanese Wagyu, the latter from the Australian herd. Even though the power of exclusion was high at 0.99 for both ISAG panels, the core panel performed poorly with 3.01% false-positive assignments in the Hanwoo population and 3.57% in the Wagyu. The full ISAG panel identified all sire-offspring relations correctly in both populations with 0.02% of relations wrongly excluded in the Hanwoo population. Based on these results, we created and tested two population-specific marker panels: one for the Wagyu population, which showed no false-positive assignments with either 100 or 200 SNPs, and a second panel for the Hanwoo, which still had some false-positive assignments with 100 SNPs but no false positives using 200 SNPs. In conclusion, for parentage assignment in East Asian cattle breeds, only the full ISAG panel is adequate for parentage testing. If fewer markers should be used, it is advisable to use population-specific markers rather than the ISAG panel. PMID:24730981

  11. SNP Miniplexes for Individual Identification of Random-Bred Domestic Cats.

    PubMed

    Brooks, Ashley; Creighton, Erica K; Gandolfi, Barbara; Khan, Razib; Grahn, Robert A; Lyons, Leslie A

    2016-05-01

    Phenotypic and genotypic characteristics of the cat can be obtained from single nucleotide polymorphisms (SNPs) analyses of fur. This study developed miniplexes using SNPs with high discriminating power for random-bred domestic cats, focusing on individual and phenotypic identification. Seventy-eight SNPs were investigated using a multiplex PCR followed by a fluorescently labeled single base extension (SBE) technique (SNaPshot(®) ). The SNP miniplexes were evaluated for reliability, reproducibility, sensitivity, species specificity, detection limitations, and assignment accuracy. Six SNPplexes were developed containing 39 intergenic SNPs and 26 phenotypic SNPs, including a sex identification marker, ZFXY. The combined random match probability (cRMP) was 6.58 × 10(-19) across all Western cat populations and the likelihood ratio was 1.52 × 10(18) . These SNPplexes can distinguish individual cats and their phenotypic traits, which could provide insight into crime reconstructions. A SNP database of 237 cats from 13 worldwide populations is now available for forensic applications. PMID:27122395

  12. Informatics Enhanced SNP Microarray Analysis of 30 Miscarriage Samples Compared to Routine Cytogenetics

    PubMed Central

    Lathi, Ruth B.; Loring, Megan; Massie, Jamie A. M.; Demko, Zachary P.; Johnson, David; Sigurjonsson, Styrmir; Gemelos, George; Rabinowitz, Matthew

    2012-01-01

    Purpose The metaphase karyotype is often used as a diagnostic tool in the setting of early miscarriage; however this technique has several limitations. We evaluate a new technique for karyotyping that uses single nucleotide polymorphism microarrays (SNP). This technique was compared in a blinded, prospective fashion, to the traditional metaphase karyotype. Methods Patients undergoing dilation and curettage for first trimester miscarriage between February and August 2010 were enrolled. Samples of chorionic villi were equally divided and sent for microarray testing in parallel with routine cytogenetic testing. Results Thirty samples were analyzed, with only four discordant results. Discordant results occurred when the entire genome was duplicated or when a balanced rearrangement was present. Cytogenetic karyotyping took an average of 29 days while microarray-based karytoyping took an average of 12 days. Conclusions Molecular karyotyping of POC after missed abortion using SNP microarray analysis allows for the ability to detect maternal cell contamination and provides rapid results with good concordance to standard cytogenetic analysis. PMID:22403611

  13. A Pipeline for Classifying Relationships Using Dense SNP/SNV Data and Putative Pedigree Information.

    PubMed

    Zeng, Zhen; Weeks, Daniel E; Chen, Wei; Mukhopadhyay, Nandita; Feingold, Eleanor

    2016-02-01

    When genome-wide association studies (GWAS) or sequencing studies are performed on family-based datasets, the genotype data can be used to check the structure of putative pedigrees. Even in datasets of putatively unrelated people, close relationships can often be detected using dense single-nucleotide polymorphism/variant (SNP/SNV) data. A number of methods for finding relationships using dense genetic data exist, but they all have certain limitations, including that they typically use average genetic sharing, which is only a subset of the available information. Here, we present a set of approaches for classifying relationships in GWAS datasets or large-scale sequencing datasets. We first propose an empirical method for detecting identity by descent segments in close relative pairs using un-phased dense SNP data and demonstrate how that information can assist in building a relationship classifier. We then develop a strategy to take advantage of putative pedigree information to enhance classification accuracy. Our methods are tested and illustrated with two datasets from two distinct populations. Finally, we propose classification pipelines for checking and identifying relationships in datasets containing a large number of small pedigrees. PMID:26709242

  14. Melanin-based colour polymorphism responding to climate change.

    PubMed

    Roulin, Alexandre

    2014-11-01

    Climate warming leads to a decrease in biodiversity. Organisms can deal with the new prevailing environmental conditions by one of two main routes, namely evolving new genetic adaptations or through phenotypic plasticity to modify behaviour and physiology. Melanin-based colouration has important functions in animals including a role in camouflage and thermoregulation, protection against UV-radiation and pathogens and, furthermore, genes involved in melanogenesis can pleiotropically regulate behaviour and physiology. In this article, I review the current evidence that differently coloured individuals are differentially sensitive to climate change. Predicting which of dark or pale colour variants (or morphs) will be more penalized by climate change will depend on the adaptive function of melanism in each species as well as how the degree of colouration covaries with behaviour and physiology. For instance, because climate change leads to a rise in temperature and UV-radiation and dark colouration plays a role in UV-protection, dark individuals may be less affected from global warming, if this phenomenon implies more solar radiation particularly in habitats of pale individuals. In contrast, as desertification increases, pale colouration may expand in those regions, whereas dark colourations may expand in regions where humidity is predicted to increase. Dark colouration may be also indirectly selected by climate warming because genes involved in the production of melanin pigments confer resistance to a number of stressful factors including those associated with climate warming. Furthermore, darker melanic individuals are commonly more aggressive than paler conspecifics, and hence they may better cope with competitive interactions due to invading species that expand their range in northern latitudes and at higher altitudes. To conclude, melanin may be a major component involved in adaptation to climate warming, and hence in animal populations melanin-based colouration is

  15. Exploring polymorphism of benzene and naphthalene with free energy based enhanced molecular dynamics.

    PubMed

    Schneider, Elia; Vogt, Leslie; Tuckerman, Mark E

    2016-08-01

    Prediction and exploration of possible polymorphism in organic crystal compounds are of great importance for industries ranging from organic electronics to pharmaceuticals to high-energy materials. Here we apply our crystal structure prediction procedure and the enhanced molecular dynamics based sampling approach called the Crystal-Adiabatic Free Energy Dynamics (Crystal-AFED) method to benzene and naphthalene. Crystal-AFED allows the free energy landscape of structures to be explored efficiently at any desired temperature and pressure. For each system, we successfully predict the most stable crystal structures at atmospheric pressure and explore the relative Gibbs free energies of predicted polymorphs at high pressures. Using Crystal-AFED sampling, we find that mixed structures, which typically cannot be discovered by standard crystal structure prediction methods, are prevalent in the solid forms of these compounds at high pressure. PMID:27484375

  16. Dimerization and opposite base-dependent catalytic impairment of polymorphic S326C OGG1 glycosylase

    PubMed Central

    Hill, Jeff W.; Evans, Michele K.

    2006-01-01

    Human 8-oxoguanine-DNA glycosylase (OGG1) is the major enzyme for repairing 8-oxoguanine (8-oxoG), a mutagenic guanine base lesion produced by reactive oxygen species (ROS). A frequently occurring OGG1 polymorphism in human populations results in the substitution of serine 326 for cysteine (S326C). The 326 C/C genotype is linked to numerous cancers, although the mechanism of carcinogenesis associated with the variant is unclear. We performed detailed enzymatic studies of polymorphic OGG1 and found functional defects in the enzyme. S326C OGG1 excised 8-oxoG from duplex DNA and cleaved abasic sites at rates 2- to 6-fold lower than the wild-type enzyme, depending upon the base opposite the lesion. Binding experiments showed that the polymorphic OGG1 binds DNA damage with significantly less affinity than the wild-type enzyme. Remarkably, gel shift, chemical cross-linking and gel filtration experiments showed that S326C both exists in solution and binds damaged DNA as a dimer. S326C OGG1 enzyme expressed in human cells was also found to have reduced activity and a dimeric conformation. The glycosylase activity of S326C OGG1 was not significantly stimulated by the presence of AP-endonuclease. The altered substrate specificity, lack of stimulation by AP-endonuclease 1 (APE1) and anomalous DNA binding conformation of S326C OGG1 may contribute to its linkage to cancer incidence. PMID:16549874

  17. Effect of Bcl-2 rs956572 SNP on regional gray matter volumes and cognitive function in elderly males without dementia.

    PubMed

    Liu, Mu-En; Huang, Chu-Chung; Hwang, Jen-Ping; Yang, Albert C; Tu, Pei-Chi; Yeh, Heng-Liang; Hong, Chen-Jee; Liou, Ying-Jay; Chen, Jin-Fan; Lin, Ching-Po; Tsai, Shih-Jen

    2013-04-01

    The Bcl-2 gene is a major regulator of neural plasticity and cellular resilience. A single-nucleotide polymorphism (SNP) in the Bcl-2 gene, Bcl-2 rs956572, significantly modulates the expression of Bcl-2 protein and cellular vulnerability to apoptosis. This study investigated the association between the Bcl-2 rs956572 SNP and brain structural abnormalities in non-demented elders, and to test the relationship between neuropsychological performance and regional gray matter (GM) volumes. Our sample comprised 97 non-demented elderly men with a mean age of 80.6 ± 5.6 years (range, 65 to 92 years). Cognitive test results, magnetic resonance imaging, and genotyping of Bcl-2 rs956572 were examined for each subject. The differences in regional GM volumes between G homozygotes and A-allele carriers were tested using optimized voxel-based morphometry. Subjects with G homozygotes exhibited significantly worse performance in the language domain of the Cognitive Abilities Screening Instrument (CASI; p = 0.009). They also showed significantly smaller GM volumes in the right middle temporal gyrus (MTG) (BA 21), but larger GM volumes in the left precuneus (BA 31), right lingual gyrus (BA 18), and left superior occipital gyrus (BA 19) relative to A-allele carriers (p < 0.001). A trend toward a positive correlation between right MTG GM volumes and the language domain of CASI was also evident (r = 0.181; p = 0.081). The findings suggest that Bcl-2 rs956572 SNP may modulate cognitive function and regional GM volume in non-demented elderly men, and that this polymorphism may affect language performance through its effect on the right MTG. PMID:22198673

  18. SNP Discovery by GBS in Olive and the Construction of a High-Density Genetic Linkage Map.

    PubMed

    İpek, Ahmet; Yılmaz, Kübra; Sıkıcı, Pelin; Tangu, Nesrin Aktepe; Öz, Ayşe Tülin; Bayraktar, Murat; İpek, Meryem; Gülen, Hatice

    2016-06-01

    Genetic linkage maps are valuable tools for genetic, genomic, and crop breeding studies. Several genetic linkage maps were constructed for the olive (Olea europaea L.) genome, mainly using amplified fragment length polymorphisms (AFLPs) and simple sequence repeat (SSR) markers. However, AFLPs and SSR markers were not enough to develop a high-density olive linkage map. Genotyping-by-sequencing (GBS), a recently developed single-nucleotide polymorphism (SNP) identification methodology based on next-generation sequencing (NGS) technologies, has been demonstrated to be useful for the identification of a high number of SNP markers and the construction of high-density genetic linkage maps. In the present study, we identified a total of 10,941 SNPs from a cross between the olive cultivars 'Gemlik' and 'Edincik Su' using GBS and de novo SNP discovery implemented in the computer program "Stacks." A high-density genetic linkage map for the olive genome was constructed using 121 cross-pollinated full-sib F1 progeny and 5643 markers (21 SSRs, 203 AFLPs, and 5736 SNPs). This linkage map was composed of 25 linkage groups, covering 3049 cM of the olive genome, and the mean distance between the flanking markers was 0.53 cM. To the best of our knowledge, this map is the most saturated genetic linkage map in olive to date. We demonstrated that GBS is a valuable tool for the identification of thousands of SNPs for the construction of a saturated genetic linkage map in olive. The high-density genetic map developed in this study is a useful tool for locating quantitative trait loci and other economically important traits in the olive genome. PMID:26902470

  19. Comparison of significant single nucleotide polymorphisms selections in GWAS for complex traits.

    PubMed

    Frąszczak, M; Szyda, J

    2016-05-01

    The goal of this study was to compare significant SNP selection approaches in the context of complex traits based on SNP estimates obtained by models: a model fitting a single SNP (M1), a model fitting a single SNP and a random polygenic effect (M2), the nonparametric CAR score (M3), a SNP-BLUP model with random effects of all SNPs fitted simultaneously (M4). There were 46,267 SNPs tested in a population of 2601 Holstein Friesian bulls, four traits (milk and fat yields, somatic cell score, non-return rate for heifers) were considered. The numbers of SNPs selected as significant differed among models. M1 selected a very large number of SNPs, except for a NRH in which no SNPs were significant. M2 and M3 both selected similar and low number of SNPs for each trait. M4 selected more SNPs than M2 and M3. Considering linkage disequilibrium between SNPs, for MY M2 and M3 selected SNPs more highly correlated with each other than in the case of M4, while for FY M3 selection contained more correlated SNPs than M2 and M4. In conclusion, if the research interest is to identify SNPs not only with strong, but also with moderate effects on a complex trait a multiple-SNP model is recommended. Such models are capable of accounting for at least a part of linkage disequilibrium between SNPs through the design matrix of SNP effects. Functional annotation of SNPs significant in M4 reveals good correspondence between selected polymorphisms and functional information as well as with QTL mapping results. PMID:26294278

  20. Identification of a Sex-Linked SNP Marker in the Salmon Louse (Lepeophtheirus salmonis) Using RAD Sequencing

    PubMed Central

    Taggart, John B.; Christie, Hayden R. L.; Bassett, David I.; Bron, James E.; Skuce, Philip J.; Gharbi, Karim; Skern-Mauritzen, Rasmus; Sturm, Armin

    2013-01-01

    The salmon louse (Lepeophtheirus salmonis (Krøyer, 1837)) is a parasitic copepod that can, if untreated, cause considerable damage to Atlantic salmon (Salmo salar Linnaeus, 1758) and incurs significant costs to the Atlantic salmon mariculture industry. Salmon lice are gonochoristic and normally show sex ratios close to 1:1. While this observation suggests that sex determination in salmon lice is genetic, with only minor environmental influences, the mechanism of sex determination in the salmon louse is unknown. This paper describes the identification of a sex-linked Single Nucleotide Polymorphism (SNP) marker, providing the first evidence for a genetic mechanism of sex determination in the salmon louse. Restriction site-associated DNA sequencing (RAD-seq) was used to isolate SNP markers in a laboratory-maintained salmon louse strain. A total of 85 million raw Illumina 100 base paired-end reads produced 281,838 unique RAD-tags across 24 unrelated individuals. RAD marker Lsa101901 showed complete association with phenotypic sex for all individuals analysed, being heterozygous in females and homozygous in males. Using an allele-specific PCR assay for genotyping, this SNP association pattern was further confirmed for three unrelated salmon louse strains, displaying complete association with phenotypic sex in a total of 96 genotyped individuals. The marker Lsa101901 was located in the coding region of the prohibitin-2 gene, which showed a sex-dependent differential expression, with mRNA levels determined by RT-qPCR about 1.8-fold higher in adult female than adult male salmon lice. This study’s observations of a novel sex-linked SNP marker are consistent with sex determination in the salmon louse being genetic and following a female heterozygous system. Marker Lsa101901 provides a tool to determine the genetic sex of salmon lice, and could be useful in the development of control strategies. PMID:24147087

  1. Methylenetetrahydrofolate reductase gene A1298C polymorphism in pediatric stroke--case-control and family-based study.

    PubMed

    Balcerzyk, Anna; Niemiec, Paweł; Kopyta, Ilona; Emich-Widera, Ewa; Pilarska, Ewa; Pienczk-Ręcławowicz, Karolina; Kaciński, Marek; Wendorff, Janusz; Żak, Iwona

    2015-01-01

    Moderate hyperhomocysteinemia is one of the risk factors of pediatric stroke. Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme, which regulates homocysteine metabolism, and some polymorphisms of gene encoding this enzyme are associated with a decreased activity of the enzyme. The aim of the study was to assess an association between the A1298C polymorphism and pediatric stroke. We also evaluated a possible synergistic effect of A1298C and C677T polymorphisms of this gene. The study group consisted of 88 children after ischemic stroke, 142 of their parents and 111 controls. The A1298C polymorphism was genotyped using the restriction fragment length polymorphism method. We used 2 study designs: a case-control model and a family-based association test. The Statistica 7.1 and EpiInfo 6 softwares were used in all analyses. We did not observe any statistically significant differences either in the transmission of the A allele in the family-based test or in the frequency of the A allele in the patients group compared with the controls. We also did not notice any significant additive or synergistic effects between the A1298C and C677T polymorphisms. An analysis of the results obtained in this study and a critical review of previously published studies indicate that the A1298C polymorphism of the MTHFR gene is not related to ischemic stroke in children. PMID:25440348

  2. Association of IL-1α rs17561 and IL-1 RN rs315952 polymorphisms with Tourette syndrome: a family-based study

    PubMed Central

    He, Fan; Shao, Xiaohui; Yi, Mingji; Wang, Yu; Wang, Chuan-Yue; Liu, Shiguo

    2015-01-01

    Aim: Immune system dysregulation has been implicated to play a key role in pathogenesis of Tourette syndrome (TS). IL-1α and IL-1RN are important inflammatory cytokines that mediate the inflammation. In this study, we investigated the relationship between single-nucleotide polymorphisms (SNPs) of IL-1α and IL-1RN and the susceptibility to TS in Chinese Han population. Methods: A total of 276 children with TS and their parents were recruited in the study. All DNA from our subjects were genotyped for SNPs of IL-1α rs17561 and IL-1RN rs315952 using predesigned TaqMan SNP genotyping assay. The genetic contributions of two polymorphisms were evaluated using transmission disequilibrium test (TDT) and haplotype relative risk (HRR) design. In addition, to increase the efficiency of the test, the haplotype-based HRR (HHRR) was performed. Results: No significant differences were observed in allelic and genotypic frequency of rs17561 in IL-1α and rs315952 in IL-1RN between the transmitted group and non-transmitted group (for IL-1α rs17561: TDT=0.890, df=1, P=0.402; HRR=1.011, X2=3.016, P=0.082, 95% CI=0.999-1.024; for IL-1RN rs315952: TDT=0.095, df=1, P=0.805; HRR=0.984, X2=0.008, P=0.929, 95% CI=0.695-1.394). Similarly, the analysis of HHRR also did not support a significant association (for IL-1α rs17561: HHRR=1.226, X2=0.915, P=0.339, 95% CI=0.807-1.863; for IL-1RN rs315952: HHRR=0.963, X2=0.094, P=0.759, 95% CI=0.758-1.225). Conclusion: Our results suggest that IL-1α rs17561 and IL-1RN rs315952 polymorphisms may not be associated with susceptibility to TS in Chinese Han population. However, the results still need to be replicated in a larger sample size and different populations. PMID:26097611

  3. RNA-Seq identifies SNP markers for growth traits in rainbow trout.

    PubMed

    Salem, Mohamed; Vallejo, Roger L; Leeds, Timothy D; Palti, Yniv; Liu, Sixin; Sabbagh, Annas; Rexroad, Caird E; Yao, Jianbo

    2012-01-01

    Fast growth is an important and highly desired trait, which affects the profitability of food animal production, with feed costs accounting for the largest proportion of production costs. Traditional phenotype-based selection is typically used to select for growth traits; however, genetic improvement is slow over generations. Single nucleotide polymorphisms (SNPs) explain 90% of the genetic differences between individuals; therefore, they are most suitable for genetic evaluation and strategies that employ molecular genetics for selective breeding. SNPs found within or near a coding sequence are of particular interest because they are more likely to alter the biological function of a protein. We aimed to use SNPs to identify markers and genes associated with genetic variation in growth. RNA-Seq whole-transcriptome analysis of pooled cDNA samples from a population of rainbow trout selected for improved growth versus unselected genetic cohorts (10 fish from 1 full-sib family each) identified SNP markers associated with growth-rate. The allelic imbalances (the ratio between the allele frequencies of the fast growing sample and that of the slow growing sample) were considered at scores >5.0 as an amplification and <0.2 as loss of heterozygosity. A subset of SNPs (n = 54) were validated and evaluated for association with growth traits in 778 individuals of a three-generation parent/offspring panel representing 40 families. Twenty-two SNP markers and one mitochondrial haplotype were significantly associated with growth traits. Polymorphism of 48 of the markers was confirmed in other commercially important aquaculture stocks. Many markers were clustered into genes of metabolic energy production pathways and are suitable candidates for genetic selection. The study demonstrates that RNA-Seq at low sequence coverage of divergent populations is a fast and effective means of identifying SNPs, with allelic imbalances between phenotypes. This technique is suitable for marker

  4. Identification of SNP and SSR Markers in Finger Millet Using Next Generation Sequencing Technologies

    PubMed Central

    Gimode, Davis; Odeny, Damaris A.; de Villiers, Etienne P.; Wanyonyi, Solomon; Dida, Mathews M.; Mneney, Emmarold E.; Muchugi, Alice; Machuka, Jesse; de Villiers, Santie M.

    2016-01-01

    Finger millet is an important cereal crop in eastern Africa and southern India with excellent grain storage quality and unique ability to thrive in extreme environmental conditions. Since negligible attention has been paid to improving this crop to date, the current study used Next Generation Sequencing (NGS) technologies to develop both Simple Sequence Repeat (SSR) and Single Nucleotide Polymorphism (SNP) markers. Genomic DNA from cultivated finger millet genotypes KNE755 and KNE796 was sequenced using both Roche 454 and Illumina technologies. Non-organelle sequencing reads were assembled into 207 Mbp representing approximately 13% of the finger millet genome. We identified 10,327 SSRs and 23,285 non-homeologous SNPs and tested 101 of each for polymorphism across a diverse set of wild and cultivated finger millet germplasm. For the 49 polymorphic SSRs, the mean polymorphism information content (PIC) was 0.42, ranging from 0.16 to 0.77. We also validated 92 SNP markers, 80 of which were polymorphic with a mean PIC of 0.29 across 30 wild and 59 cultivated accessions. Seventy-six of the 80 SNPs were polymorphic across 30 wild germplasm with a mean PIC of 0.30 while only 22 of the SNP markers showed polymorphism among the 59 cultivated accessions with an average PIC value of 0.15. Genetic diversity analysis using the polymorphic SNP markers revealed two major clusters; one of wild and another of cultivated accessions. Detailed STRUCTURE analysis confirmed this grouping pattern and further revealed 2 sub-populations within wild E. coracana subsp. africana. Both STRUCTURE and genetic diversity analysis assisted with the correct identification of the new germplasm collections. These polymorphic SSR and SNP markers are a significant addition to the existing 82 published SSRs, especially with regard to the previously reported low polymorphism levels in finger millet. Our results also reveal an unexploited finger millet genetic resource that can be included in the regional

  5. Construction of a genetic map based on high-throughput SNP genotyping and genetic mapping of a TuMV resistance locus in Brassica rapa.

    PubMed

    Chung, Hee; Jeong, Young-Min; Mun, Jeong-Hwan; Lee, Soo-Seong; Chung, Won-Hyong; Yu, Hee-Ju

    2014-04-01

    Brassica rapa is a member of the Brassicaceae family and includes vegetables and oil crops that are cultivated worldwide. The introduction of durable resistance against turnip mosaic virus (TuMV) into agronomically important cultivars has been a significant challenge for genetic and horticultural breeding studies of B. rapa. Based on our previous genome-wide analysis of DNA polymorphisms between the TuMV-resistant doubled haploid (DH) line VC40 and the TuMV-susceptible DH line SR5, we constructed a core genetic map of the VCS-13M DH population, which is composed of 83 individuals derived from microspore cultures of a F1 cross between VC40 and SR5, by analyzing the segregation of 314 sequence-characterized genetic markers. The genetic markers correspond to 221 SNPs and 31 InDels of genes as well as 62 SSRs, covering 1,115.9 cM with an average distance of 3.6 cM between the adjacent marker loci. The alignment and orientation of the constructed map showed good agreement with the draft genome sequence of Chiifu, thus providing an efficient strategy to map genic sequences. Using the genetic map, a novel dominant TuMV resistance locus (TuMV-R) in the VCS-13M DH population was identified as a 0.34 Mb region in the short arm of chromosome A6 in which four CC-NBS-LRR resistance genes and two pathogenesis-related-1 genes reside. The genetic map developed in this study can play an important role in the genetic study of TuMV resistance and the molecular breeding of B. rapa. PMID:24326528

  6. The utility of high-resolution melting analysis of SNP nucleated PCR amplicons--an MLST based Staphylococcus aureus typing scheme.

    PubMed

    Lilliebridge, Rachael A; Tong, Steven Y C; Giffard, Philip M; Holt, Deborah C

    2011-01-01

    High resolution melting (HRM) analysis is gaining prominence as a method for discriminating DNA sequence variants. Its advantage is that it is performed in a real-time PCR device, and the PCR amplification and HRM analysis are closed tube, and effectively single step. We have developed an HRM-based method for Staphylococcus aureus genotyping. Eight single nucleotide polymorphisms (SNPs) were derived from the S. aureus multi-locus sequence typing (MLST) database on the basis of maximized Simpson's Index of Diversity. Only G↔A, G↔T, C↔A, C↔T SNPs were considered for inclusion, to facilitate allele discrimination by HRM. In silico experiments revealed that DNA fragments incorporating the SNPs give much higher resolving power than randomly selected fragments. It was shown that the predicted optimum fragment size for HRM analysis was 200 bp, and that other SNPs within the fragments contribute to the resolving power. Six DNA fragments ranging from 83 bp to 219 bp, incorporating the resolution optimized SNPs were designed. HRM analysis of these fragments using 94 diverse S. aureus isolates of known sequence type or clonal complex (CC) revealed that sequence variants are resolved largely in accordance with G+C content. A combination of experimental results and in silico prediction indicates that HRM analysis resolves S. aureus into 268 "melt types" (MelTs), and provides a Simpson's Index of Diversity of 0.978 with respect to MLST. There is a high concordance between HRM analysis and the MLST defined CCs. We have generated a Microsoft Excel key which facilitates data interpretation and translation between MelT and MLST data. The potential of this approach for genotyping other bacterial pathogens was investigated using a computerized approach to estimate the densities of SNPs with unlinked allelic states. The MLST databases for all species tested contained abundant unlinked SNPs, thus suggesting that high resolving power is not dependent upon large numbers of SNPs

  7. No association of IFNG+874T/A SNP and NOS2A-954G/C SNP variants with nitric oxide radical serum levels or susceptibility to tuberculosis in a Brazilian population subset.

    PubMed

    Leandro, Ana Cristina C S; Rocha, Márcia Andrade; Lamoglia-Souza, Andreia; VandeBerg, John L; Rolla, Valeria Cavalcanti; Bonecini-Almeida, Maria da Gloria

    2013-01-01

    Tuberculosis (TB) is one of the most common infectious diseases in the world. Mycobacterium tuberculosis infection leads to pulmonary active disease in approximately 5-10% of exposed individuals. Both bacteria- and host-related characteristics influence latent infection and disease. Host genetic predisposition to develop TB may involve multiple genes and their polymorphisms. It was reported previously that interferon gamma (IFN-γ) and nitric oxide synthase 2 (NOS2) are expressed on alveolar macrophages from TB patients and are responsible for bacilli control; thus, we aimed this study at genotyping single nucleotide polymorphisms IFNG+874T/A SNP and NOS2A-954G/C SNP to estimate their role on TB susceptibility and determine whether these polymorphisms influence serum nitrite and NOx(-) production. This case-control study enrolled 172 TB patients and 179 healthy controls. Neither polymorphism was associated with susceptibility to TB. NOS2A-954G/C SNP was not associated with serum levels of nitrite and NOx(-). These results indicate that variants of IFNG+874T/A SNP and NOS2A-954G/C SNP do not influence TB susceptibility or the secretion of nitric oxide radicals in the study population. PMID:24024215

  8. A system for exact and approximate genetic linkage analysis of SNP data in large pedigrees

    PubMed Central

    Silberstein, Mark; Weissbrod, Omer; Otten, Lars; Tzemach, Anna; Anisenia, Andrei; Shtark, Oren; Tuberg, Dvir; Galfrin, Eddie; Gannon, Irena; Shalata, Adel; Borochowitz, Zvi U.; Dechter, Rina; Thompson, Elizabeth; Geiger, Dan

    2013-01-01

    Motivation: The use of dense single nucleotide polymorphism (SNP) data in genetic linkage analysis of large pedigrees is impeded by significant technical, methodological and computational challenges. Here we describe Superlink-Online SNP, a new powerful online system that streamlines the linkage analysis of SNP data. It features a fully integrated flexible processing workflow comprising both well-known and novel data analysis tools, including SNP clustering, erroneous data filtering, exact and approximate LOD calculations and maximum-likelihood haplotyping. The system draws its power from thousands of CPUs, performing data analysis tasks orders of magnitude faster than a single computer. By providing an intuitive interface to sophisticated state-of-the-art analysis tools coupled with high computing capacity, Superlink-Online SNP helps geneticists unleash the potential of SNP data for detecting disease genes. Results: Computations performed by Superlink-Online SNP are automatically parallelized using novel paradigms, and executed on unlimited number of private or public CPUs. One novel service is large-scale approximate Markov Chain–Monte Carlo (MCMC) analysis. The accuracy of the results is reliably estimated by running the same computation on multiple CPUs and evaluating the Gelman–Rubin Score to set aside unreliable results. Another service within the workflow is a novel parallelized exact algorithm for inferring maximum-likelihood haplotyping. The reported system enables genetic analyses that were previously infeasible. We demonstrate the system capabilities through a study of a large complex pedigree affected with metabolic syndrome. Availability: Superlink-Online SNP is freely available for researchers at http://cbl-hap.cs.technion.ac.il/superlink-snp. The system source code can also be downloaded from the system website. Contact: omerw@cs.technion.ac.il Supplementary information: Supplementary data are available at Bioinformatics online. PMID:23162081

  9. FunctSNP: an R package to link SNPs to functional knowledge and dbAutoMaker: a suite of Perl scripts to build SNP databases

    PubMed Central

    2010-01-01

    Background Whole genome association studies using highly dense single nucleotide polymorphisms (SNPs) are a set of methods to identify DNA markers associated with variation in a particular complex trait of interest. One of the main outcomes from these studies is a subset of statistically significant SNPs. Finding the potential biological functions of such SNPs can be an important step towards further use in human and agricultural populations (e.g., for identifying genes related to susceptibility to complex diseases or genes playing key roles in development or performance). The current challenge is that the information holding the clues to SNP functions is distributed across many different databases. Efficient bioinformatics tools are therefore needed to seamlessly integrate up-to-date functional information on SNPs. Many web services have arisen to meet the challenge but most work only within the framework of human medical research. Although we acknowledge the importance of human research, we identify there is a need for SNP annotation tools for other organisms. Description We introduce an R package called FunctSNP, which is the user interface to custom built species-specific databases. The local relational databases contain SNP data together with functional annotations extracted from online resources. FunctSNP provides a unified bioinformatics resource to link SNPs with functional knowledge (e.g., genes, pathways, ontologies). We also introduce dbAutoMaker, a suite of Perl scripts, which can be scheduled to run periodically to automatically create/update the customised SNP databases. We illustrate the use of FunctSNP with a livestock example, but the approach and software tools presented here can be applied also to human and other organisms. Conclusions Finding the potential functional significance of SNPs is important when further using the outcomes from whole genome association studies. FunctSNP is unique in that it is the only R package that links SNPs to

  10. Development of a forensic identity SNP panel for Indonesia.

    PubMed

    Augustinus, Daniel; Gahan, Michelle E; McNevin, Dennis

    2015-07-01

    Genetic markers included in forensic identity panels must exhibit Hardy-Weinberg and linkage equilibrium (HWE and LE). "Universal" panels designed for global use can fail these tests in regional jurisdictions exhibiting high levels of genetic differentiation such as the Indonesian archipelago. This is especially the case where a single DNA database is required for allele frequency estimates to calculate random match probabilities (RMPs) and associated likelihood ratios (LRs). A panel of 65 single nucleotide polymorphisms (SNPs) and a reduced set of 52 SNPs have been selected from 15 Indonesian subpopulations in the HUGO Pan Asian SNP database using a SNP selection strategy that could be applied to any panel of forensic identity markers. The strategy consists of four screening steps: (1) application of a G test for HWE; (2) ranking for high heterozygosity; (3) selection for LE; and (4) selection for low inbreeding depression. SNPs in our Indonesian panel perform well in comparison to some other universal SNP and short tandem repeat (STR) panels as measured by Fisher's exact test for HWE and LE and Wright's F statistics. PMID:25104323

  11. Reliable In Silico Identification of Sequence Polymorphisms and Their Application for Extending the Genetic Map of Sugar Beet (Beta vulgaris)

    PubMed Central

    Holtgräwe, Daniela; Sörensen, Thomas Rosleff; Viehöver, Prisca; Schneider, Jessica; Schulz, Britta; Borchardt, Dietrich; Kraft, Thomas; Himmelbauer, Heinz; Weisshaar, Bernd

    2014-01-01

    Molecular markers are a highly valuable tool for creating genetic maps. Like in many other crops, sugar beet (Beta vulgaris L.) breeding is increasingly supported by the application of such genetic markers. Single nucleotide polymorphism (SNP) based markers have a high potential for automated analysis and high-throughput genotyping. We developed a bioinformatics workflow that uses Sanger and 2nd-generation sequence data for detection, evaluation and verification of new transcript-associated SNPs from sugar beet. RNAseq data from one parent of an established mapping population were produced by 454-FLX sequencing and compared to Sanger ESTs derived from the other parent. The workflow established for SNP detection considers the quality values of both types of reads, provides polymorphic alignments as well as selection criteria for reliable SNP detection and allows painless generation of new genetic markers within genes. We obtained a total of 14,323 genic SNPs and InDels. According to empirically optimised settings for the quality parameters, we classified these SNPs into four usability categories. Validation of a subset of the in silico detected SNPs by genotyping the mapping population indicated a high success rate of the SNP detection. Finally, a total of 307 new markers were integrated with existing data into a new genetic map of sugar beet which offers improved resolution and the integration of terminal markers. PMID:25302600

  12. Genomic and genotyping characterization of haplotype-based polymorphic microsatellites in Prunus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Efficient utilization of microsatellites in genetic studies remains impeded largely due to the unknown status of their primer reliability, chromosomal location, and allele polymorphism. Discovery and characterization of microsatellite polymorphisms in a taxon will disclose the unknowns and gain new ...

  13. B-DNA structure is intrinsically polymorphic: even at the level of base pair positions

    SciTech Connect

    Maehigashi, Tatsuya; Hsiao, Chiaolong; Woods, Kristen Kruger; Moulaei, Tinoush; Hud, Nicholas V.; Williams, Loren Dean

    2012-10-23

    Increasingly exact measurement of single crystal X-ray diffraction data offers detailed characterization of DNA conformation, hydration and electrostatics. However, instead of providing a more clear and unambiguous image of DNA, highly accurate diffraction data reveal polymorphism of the DNA atomic positions and conformation and hydration. Here we describe an accurate X-ray structure of B-DNA, painstakingly fit to a multistate model that contains multiple competing positions of most of the backbone and of entire base pairs. Two of ten base-pairs of CCAGGCCTGG are in multiple states distinguished primarily by differences in slide. Similarly, all the surrounding ions are seen to fractionally occupy discrete competing and overlapping sites. And finally, the vast majority of water molecules show strong evidence of multiple competing sites. Conventional resolution appears to give a false sense of homogeneity in conformation and interactions of DNA. In addition, conventional resolution yields an average structure that is not accurate, in that it is different from any of the multiple discrete structures observed at high resolution. Because base pair positional heterogeneity has not always been incorporated into model-building, even some high and ultrahigh-resolution structures of DNA do not indicate the full extent of conformational polymorphism.

  14. High-resolution SNP arrays in mental retardation diagnostics: how much do we gain?

    PubMed Central

    Bernardini, Laura; Alesi, Viola; Loddo, Sara; Novelli, Antonio; Bottillo, Irene; Battaglia, Agatino; Digilio, Maria Cristina; Zampino, Giuseppe; Ertel, Adam; Fortina, Paolo; Surrey, Saul; Dallapiccola, Bruno

    2010-01-01

    We used Affymetrix 6.0 GeneChip SNP arrays to characterize copy number variations (CNVs) in a cohort of 70 patients previously characterized on lower-density oligonucleotide arrays affected by idiopathic mental retardation and dysmorphic features. The SNP array platform includes ∼900 000 SNP probes and 900 000 non-SNP oligonucleotide probes at an average distance of 0.7 Kb, which facilitates coverage of the whole genome, including coding and noncoding regions. The high density of probes is critical for detecting small CNVs, but it can lead to data interpretation problems. To reduce the number of false positives, parameters were set to consider only imbalances >75 Kb encompassing at least 80 probe sets. The higher resolution of the SNP array platform confirmed the increased ability to detect small CNVs, although more than 80% of these CNVs overlapped to copy number ‘neutral' polymorphism regions and 4.4% of them did not contain known genes. In our cohort of 70 patients, of the 51 previously evaluated as ‘normal' on the Agilent 44K array, the SNP array platform disclosed six additional CNV changes, including three in three patients, which may be pathogenic. This suggests that about 6% of individuals classified as ‘normal' using the lower-density oligonucleotide array could be found to be affected by a genomic disorder when evaluated with the higher-density microarray platforms. PMID:19809473

  15. Hybridization modeling of oligonucleotide SNP arrays for accurate DNA copy number estimation

    PubMed Central

    Wan, Lin; Sun, Kelian; Ding, Qi; Cui, Yuehua; Li, Ming; Wen, Yalu; Elston, Robert C.; Qian, Minping; Fu, Wenjiang J

    2009-01-01

    Affymetrix SNP arrays have been widely used for single-nucleotide polymorphism (SNP) genotype calling and DNA copy number variation inference. Although numerous methods have achieved high accuracy in these fields, most studies have paid little attention to the modeling of hybridization of probes to off-target allele sequences, which can affect the accuracy greatly. In this study, we address this issue and demonstrate that hybridization with mismatch nucleotides (HWMMN) occurs in all SNP probe-sets and has a critical effect on the estimation of allelic concentrations (ACs). We study sequence binding through binding free energy and then binding affinity, and develop a probe intensity composite representation (PICR) model. The PICR model allows the estimation of ACs at a given SNP through statistical regression. Furthermore, we demonstrate with cell-line data of known true copy numbers that the PICR model can achieve reasonable accuracy in copy number estimation at a single SNP locus, by using the ratio of the estimated AC of each sample to that of the reference sample, and can reveal subtle genotype structure of SNPs at abnormal loci. We also demonstrate with HapMap data that the PICR model yields accurate SNP genotype calls consistently across samples, laboratories and even across array platforms. PMID:19586935

  16. Genetic heterogeneity in rhabdomyosarcoma revealed by SNP array analysis.

    PubMed

    Walther, Charles; Mayrhofer, Markus; Nilsson, Jenny; Hofvander, Jakob; Jonson, Tord; Mandahl, Nils; Øra, Ingrid; Gisselsson, David; Mertens, Fredrik

    2016-01-01

    Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and adolescents. Alveolar (ARMS) and embryonal (ERMS) histologies predominate, but rare cases are classified as spindle cell/sclerosing (SRMS). For treatment stratification, RMS is further subclassified as fusion-positive (FP-RMS) or fusion-negative (FN-RMS), depending on whether a gene fusion involving PAX3 or PAX7 is present or not. We investigated 19 cases of pediatric RMS using high resolution single-nucleotide polymorphism (SNP) array. FP-ARMS displayed, on average, more structural rearrangements than ERMS; the single FN-ARMS had a genomic profile similar to ERMS. Apart from previously known amplification (e.g., MYCN, CDK4, and MIR17HG) and deletion (e.g., NF1, CDKN2A, and CDKN2B) targets, amplification of ERBB2 and homozygous loss of ASCC3 or ODZ3 were seen. Combining SNP array with cytogenetic data revealed that most cases were polyploid, with at least one case having started as a near-haploid tumor. Further bioinformatic analysis of the SNP array data disclosed genetic heterogeneity, in the form of subclonal chromosomal imbalances, in five tumors. The outcome was worse for patients with FP-ARMS than ERMS or FN-ARMS (6/8 vs. 1/9 dead of disease), and the only children with ERMS showing intratumor diversity or with MYOD1 mutation-positive SRMS also died of disease. High resolution SNP array can be useful in evaluating genomic imbalances in pediatric RMS. PMID:26482321

  17. Selection of single-nucleotide polymorphisms and quality of genotypes used in genomic evaluation of dairy cattle in the United States and Canada

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nearly 57,000 single nucleotide polymorphisms (SNP) on the Illumina BovineSNP50™ chip were investigated to determine their usefulness for genomic prediction. Genotypes were obtained for 12,591 Holstein bulls and cows and SNP selection was done using 5,503 bulls that had genotypes on a larger set of ...

  18. Molecular phylogeny and SNP variation of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) derived from genome sequences.

    PubMed

    Cronin, Matthew A; Rincon, Gonzalo; Meredith, Robert W; MacNeil, Michael D; Islas-Trejo, Alma; Cánovas, Angela; Medrano, Juan F

    2014-01-01

    We assessed the relationships of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) with high throughput genomic sequencing data with an average coverage of 25× for each species. A total of 1.4 billion 100-bp paired-end reads were assembled using the polar bear and annotated giant panda (Ailuropoda melanoleuca) genome sequences as references. We identified 13.8 million single nucleotide polymorphisms (SNP) in the 3 species aligned to the polar bear genome. These data indicate that polar bears and brown bears share more SNP with each other than either does with black bears. Concatenation and coalescence-based analysis of consensus sequences of approximately 1 million base pairs of ultraconserved elements in the nuclear genome resulted in a phylogeny with black bears as the sister group to brown and polar bears, and all brown bears are in a separate clade from polar bears. Genotypes for 162 SNP loci of 336 bears from Alaska and Montana showed that the species are genetically differentiated and there is geographic population structure of brown and black bears but not polar bears. PMID:24477675

  19. Large-Scale SNP Discovery and Genotyping for Constructing a High-Density Genetic Map of Tea Plant Using Specific-Locus Amplified Fragment Sequencing (SLAF-seq).

    PubMed

    Ma, Jian-Qiang; Huang, Long; Ma, Chun-Lei; Jin, Ji-Qiang; Li, Chun-Fang; Wang, Rong-Kai; Zheng, Hong-Kun; Yao, Ming-Zhe; Chen, Liang

    2015-01-01

    Genetic maps are important tools in plant genomics and breeding. The present study reports the large-scale discovery of single nucleotide polymorphisms (SNPs) for genetic map construction in tea plant. We developed a total of 6,042 valid SNP markers using specific-locus amplified fragment sequencing (SLAF-seq), and subsequently mapped them into the previous framework map. The final map contained 6,448 molecular markers, distributing on fifteen linkage groups corresponding to the number of tea plant chromosomes. The total map length was 3,965 cM, with an average inter-locus distance of 1.0 cM. This map is the first SNP-based reference map of tea plant, as well as the most saturated one developed to date. The SNP markers and map resources generated in this study provide a wealth of genetic information that can serve as a foundation for downstream genetic analyses, such as the fine mapping of quantitative trait loci (QTL), map-based cloning, marker-assisted selection, and anchoring of scaffolds to facilitate the process of whole genome sequencing projects for tea plant. PMID:26035838

  20. Generation of knockout alleles by RFLP based BAC targeting of polymorphic embryonic stem cells.

    PubMed

    Barakat, Tahsin Stefan; Gribnau, Joost

    2015-01-01

    The isolation of germ line competent mouse Embryonic Stem (ES) cells and the ability to modify the genome by homologous recombination has revolutionized life science research. Since its initial discovery, several approaches have been introduced to increase the efficiency of homologous recombination, including the use of isogenic DNA for the generation of targeting constructs, and the use of Bacterial Artificial Chromosomes (BACs). BACs have the advantage of combining long stretches of homologous DNA, thereby increasing targeting efficiencies, with the possibilities delivered by BAC recombineering approaches, which provide the researcher with almost unlimited possibilities to efficiently edit the genome in a controlled fashion. Despite these advantages of BAC targeting approaches, a widespread use has been hampered, mainly because of the difficulties in identifying BAC-targeted knockout alleles by conventional methods like Southern Blotting. Recently, we introduced a novel BAC targeting strategy, in which Restriction Fragment Length Polymorphisms (RFLPs) are targeted in polymorphic mouse ES cells, enabling an efficient and easy PCR-based readout to identify properly targeted alleles. Here we provide a detailed protocol for the generation of targeting constructs, targeting of ES cells, and convenient PCR-based analysis of targeted clones, which enable the user to generate knockout ES cells of almost every gene in the mouse genome within a 2-month period. PMID:25239745

  1. A novel MALDI-TOF based methodology for genotyping single nucleotide polymorphisms.

    PubMed

    Blondal, Thorarinn; Waage, Benedikt G; Smarason, Sigurdur V; Jonsson, Frosti; Fjalldal, Sigridur B; Stefansson, Kari; Gulcher, Jeffery; Smith, Albert V

    2003-12-15

    A new MALDI-TOF based detection assay was developed for analysis of single nucleotide polymorphisms (SNPs). It is a significant modification on the classic three-step minisequencing method, which includes a polymerase chain reaction (PCR), removal of excess nucleotides and primers, followed by primer extension in the presence of dideoxynucleotides using modified thermostable DNA polymerase. The key feature of this novel assay is reliance upon deoxynucleotide mixes, lacking one of the nucleotides at the polymorphic position. During primer extension in the presence of depleted nucleotide mixes, standard thermostable DNA polymerases dissociate from the template at positions requiring a depleted nucleotide; this principal was harnessed to create a genotyping assay. The assay design requires a primer- extension primer having its 3'-end one nucleotide upstream from the interrogated site. The assay further utilizes the same DNA polymerase in both PCR and the primer extension step. This not only simplifies the assay but also greatly reduces the cost per genotype compared to minisequencing methodology. We demonstrate accurate genotyping using this methodology for two SNPs run in both singleplex and duplex reactions. We term this assay nucleotide depletion genotyping (NUDGE). Nucleotide depletion genotyping could be extended to other genotyping assays based on primer extension such as detection by gel or capillary electrophoresis. PMID:14654708

  2. Genotyping of clinical Mycobacterium tuberculosis isolates based on IS6110 and MIRU-VNTR polymorphisms.

    PubMed

    Żaczek, Anna; Brzostek, Anna; Wojtasik, Arkadiusz; Dziadek, Jarosław; Sajduda, Anna

    2013-01-01

    In this study, 155 clinical Mycobacterium tuberculosis isolates were subject to genotyping with fast ligation-mediated PCR (FLiP). This typing method is a modified mixed-linker PCR, a rapid approach based on the PCR amplification of HhaI restriction fragments of genomic DNA containing the 3' end of IS6110 and resolving the amplicons by polyacrylamide gel electrophoresis. The results were compared with previous data of the more commonly used methods, 15-locus mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing and, to verify combined FLiP/MIRU-VNTR clusters, the reference IS6110 restriction fragment length polymorphism (RFLP). FLiP banding patterns were highly reproducible and polymorphic. This method differentiated 119 types among the study set compared to 108 distinct MIRU-VNTR profiles. The discriminatory power of FLiP was slightly higher than that of MIRU-VNTR analysis (Hunter-Gaston Discriminatory Index = 0.991 and 0.990, resp.). Detailed comparison of the clusters defined by each of the methods revealed, however, a more apparent difference in the discriminatory abilities that favored FLiP. Clustering of strains by using combined results of these two PCR-based methods correlated well with IS6110 RFLP-defined clusters, further confirming high discriminatory potential of FLiP typing. These results indicate that FLiP could be an attractive and valuable secondary typing technique for verification of MIRU-VNTR clusters of M. tuberculosis strains. PMID:24455734

  3. Single nucleotide polymorphism array karyotyping: a diagnostic and prognostic tool in myelodysplastic syndromes with unsuccessful conventional cytogenetic testing.

    PubMed

    Arenillas, Leonor; Mallo, Mar; Ramos, Fernando; Guinta, Kathryn; Barragán, Eva; Lumbreras, Eva; Larráyoz, María-José; De Paz, Raquel; Tormo, Mar; Abáigar, María; Pedro, Carme; Cervera, José; Such, Esperanza; José Calasanz, María; Díez-Campelo, María; Sanz, Guillermo F; Hernández, Jesús María; Luño, Elisa; Saumell, Sílvia; Maciejewski, Jaroslaw; Florensa, Lourdes; Solé, Francesc

    2013-12-01

    Cytogenetic aberrations identified by metaphase cytogenetics (MC) have diagnostic, prognostic, and therapeutic implications in myelodysplastic syndromes (MDS). However, in some MDS patients MC study is unsuccesful. Single nucleotide polymorphism array (SNP-A) based karyotyping could be helpful in these cases. We performed SNP-A in 62 samples from bone marrow or peripheral blood of primary MDS with an unsuccessful MC study. SNP-A analysis enabled the detection of aberrations in 31 (50%) patients. We used the copy number alteration information to apply the International Prognostic Scoring System (IPSS) and we observed differences in survival between the low/intermediate-1 and intermediate-2/high risk patients. We also saw differences in survival between very low/low/intermediate and the high/very high patients when we applied the revised IPSS (IPSS-R). In conclusion, SNP-A can be used successfully in PB samples and the identification of CNA by SNP-A improve the diagnostic and prognostic evaluation of this group of MDS patients. PMID:24123380

  4. Identification of a significant association of a single nucleotide polymorphism in TNXB with systemic lupus erythematosus in a Japanese population.

    PubMed

    Kamatani, Yoichiro; Matsuda, Koichi; Ohishi, Tetsuya; Ohtsubo, Shigeru; Yamazaki, Keiko; Iida, Aritoshi; Hosono, Naoya; Kubo, Michiaki; Yumura, Wako; Nitta, Kosaku; Katagiri, Toyomasa; Kawaguchi, Yasushi; Kamatani, Naoyuki; Nakamura, Yusuke

    2008-01-01

    Systemic lupus erythematosus (SLE) is one of the common autoimmune diseases, with complex genetic components. Here, we report on a case-control association study of 178 SLE patients and 899 control subjects, using genome-wide gene-based single nucleotide polymorphism (SNP) markers. An SNP, rs3130342, in a 5' flanking region of the TNXB gene revealed a significant association with SLE [P = 0.000000930, odds ratio (OR) 3.11, with 95% confidence interval (95%CI) of 1.89-5.28] in a Japanese population. This association was replicated independently with 203 cases and 294 controls (P = 0.0440, OR 1.52, with 95%CI of 1.01-2.78). Although a copy number variation (CNV) of the C4 gene adjacent to the TNXB gene was reported to be associated with SLE, our analysis on this CNV revealed that the association of CNV of the C4 gene was weaker than the SNP in the TNXB gene and likely to reflect the linkage disequilibrium between C4 CNV and this particular SNP. Stratified analysis also revealed that the association of SNP rs3130342 with SLE was independent of the HLA-DRB1*1501 allele that has been shown to be associated with SLE. Our findings strongly imply that the TNXB gene is a candidate gene susceptible to SLE in the Japanese population. PMID:18058064

  5. TP53 and MDM2 single nucleotide polymorphisms influence survival in non-del(5q) myelodysplastic syndromes.

    PubMed

    McGraw, Kathy L; Cluzeau, Thomas; Sallman, David A; Basiorka, Ashley A; Irvine, Brittany A; Zhang, Ling; Epling-Burnette, P K; Rollison, Dana E; Mallo, Mar; Sokol, Lubomir; Solé, Francesc; Maciejewski, Jaroslaw; List, Alan F

    2015-10-27

    P53 is a key regulator of many cellular processes and is negatively regulated by the human homolog of murine double minute-2 (MDM2) E3 ubiquitin ligase. Single nucleotide polymorphisms (SNPs) of either gene alone, and in combination, are linked to cancer susceptibility, disease progression, and therapy response. We analyzed the interaction of TP53 R72P and MDM2 SNP309 SNPs in relationship to outcome in patients with myelodysplastic syndromes (MDS). Sanger sequencing was performed on DNA isolated from 208 MDS cases. Utilizing a novel functional SNP scoring system ranging from +2 to -2 based on predicted p53 activity, we found statistically significant differences in overall survival (OS) (p = 0.02) and progression-free survival (PFS) (p = 0.02) in non-del(5q) MDS patients with low functional scores. In univariate analysis, only IPSS and the functional SNP score predicted OS and PFS in non-del(5q) patients. In multivariate analysis, the functional SNP score was independent of IPSS for OS and PFS. These data underscore the importance of TP53 R72P and MDM2 SNP309 SNPs in MDS, and provide a novel scoring system independent of IPSS that is predictive for disease outcome. PMID:26416416

  6. Strategies to build high-density linkage maps of the porcine 60k SNP chip

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We present here two different strategies to compute high-density linkage maps based on the porcine 60k SNP chip that was genotyped on 4 different pedigrees with a total of 5600 animals. The first strategy uses the draft sequence as a reference order, the SNP being first mapped to it. The second stra...

  7. The Single Nucleotide Polymorphism Consortium

    NASA Technical Reports Server (NTRS)

    Morgan, Michael

    2003-01-01

    I want to discuss both the Single Nucleotide Polymorphism (SNP) Consortium and the Human Genome Project. I am afraid most of my presentation will be thin on law and possibly too high on rhetoric. Having been engaged in a personal and direct way with these issues as a trained scientist, I find it quite difficult to be always as objective as I ought to be.

  8. Susceptibility to paratuberculosis infection in cattle is associated with single nucleotide polymorphisms in Toll-like receptor 2 which modulate immune responses against Mycobacterium avium subspecies paratuberculosis.

    PubMed

    Koets, A; Santema, W; Mertens, H; Oostenrijk, D; Keestra, M; Overdijk, M; Labouriau, R; Franken, P; Frijters, A; Nielen, M; Rutten, V

    2010-03-01

    Paratuberculosis is a chronic intestinal infection in ruminants, caused by Mycobacterium avium subspecies paratuberculosis (Map). To study the role of host genetics in disease susceptibility, the Toll-like receptor 2 (TLR2) gene, selected based on its potential role in immunity to mycobacterial infections, was analyzed for single nucleotide polymorphisms (SNP) and their potential association with disease. For SNP discovery and to study SNP association with disease, a case-control study including 24 cows from farms with paratuberculosis was conducted. Sequence analysis of the TLR2 genes from 12 paratuberculosis-infected animals and 12 age-matched healthy herd mates revealed 21 different SNP. The TLR2-1903 T/C SNP was significantly associated with resistance to Map. This and four additional TLR2 SNP were studied in a subsequent observational field study with 553 cows from farms with paratuberculosis. The allelic distribution of the TLR2-1903 T/C SNP was confirmed to be significantly different between the infected and non-infected animals. For the TLR2-1903 T/C SNP the odds ratio was calculated, and similar to the dominance model in the association study, the CT and CC genotypes were compared to the TT genotype. Cows with the TLR2-1903 T/C mutation (i.e., the CT and CC genotypes) were at 1.7 (95% CI: 1.2, 2.8) times the odds of being Map-infected compared to cows with the TT genotype. In in vitro functional assays, monocyte-derived macrophages from animals with a TLR2-1903 TT genotype produced more IL12p40 and IL1beta when stimulated with Map compared to cells derived from TLR2-1903 CT and CC genotypes. Also, T cell proliferative responses to mycobacterial antigens were higher in animals with a TLR2-1903 TT genotype. In conclusion, we have found a significant association between SNP TLR2-1903 T/C in the bovine TLR2 gene and bovine paratuberculosis infection. This SNP and other genetic markers could be useful in marker-assisted breeding strategies as an additional tool

  9. Rapid, economical single-nucleotide polymorphism and microsatellite discovery based on de novo assembly of a reduced representation genome in a non-model organism: a case study of Atlantic cod Gadus morhua.

    PubMed

    Carlsson, J; Gauthier, D T; Carlsson, J E L; Coughlan, J P; Dillane, E; Fitzgerald, R D; Keating, U; McGinnity, P; Mirimin, L; Cross, T F

    2013-03-01

    By combining next-generation sequencing technology (454) and reduced representation library (RRL) construction, the rapid and economical isolation of over 25 000 potential single-nucleotide polymorphisms (SNP) and >6000 putative microsatellite loci from c. 2% of the genome of the non-model teleost, Atlantic cod Gadus morhua from the Celtic Sea, south of Ireland, was demonstrated. A small-scale validation of markers indicated that 80% (11 of 14) of SNP loci and 40% (6 of 15) of the microsatellite loci could be amplified and showed variability. The results clearly show that small-scale next-generation sequencing of RRL genomes is an economical and rapid approach for simultaneous SNP and microsatellite discovery that is applicable to any species. The low cost and relatively small investment in time allows for positive exploitation of ascertainment bias to design markers applicable to specific populations and study questions. PMID:23464553

  10. IL10 Gene Polymorphisms Are Associated With Asthma Phenotypes in Children

    PubMed Central

    Lyon, Helen; Lange, Christoph; Lake, Stephen; Silverman, Edwin K.; Randolph, Adrienne G.; Kwiatkowski, David; Raby, Benjamin A.; Lazarus, Ross; Weiland, Katy M.; Laird, Nan; Weiss, Scott T.

    2013-01-01

    IL10 is an anti-inflammatory cytokine that has been found to have lower production in macrophages and mononuclear cells from asthmatics. Since reduced IL10 levels may influence the severity of asthma phenotypes, we examined IL10 single-nucleotide polymorphisms (SNPs) for association with asthma severity and allergy phenotypes as quantitative traits. Utilizing DNA samples from 518 Caucasian asthmatic children from the Childhood Asthma Management Program (CAMP) and their parents, we genotyped six IL10 SNPs: 3 in the promoter, 2 in introns, and one in the 3′ UTR. Using family-based association tests, each SNP was tested for association with asthma and allergy phenotypes individually. Population-based association analysis was performed with each SNP locus, the promoter haplotypes and the 6-loci haplotypes. The 3′ UTR SNP was significantly associated with FEV1 as a percent of predicted (FEV1PP) (P=0.0002) in both the family and population analyses. The promoter haplotype GCC was positively associated with IgE levels and FEV1PP (P=0.007 and 0.012, respectively). The promoter haplotype ATA was negatively associated with lnPC20 and FEV1PP (P=0.008 and 0.043, respectively). Polymorphisms in IL10 are associated with asthma phenotypes in this cohort. Further studies of variation in the IL10 gene may help elucidate the mechanism of asthma development in children. PMID:14748015

  11. Association study of polymorphisms in the neutral amino acid transporter genes SLC1A4, SLC1A5 and the glycine transporter genes SLC6A5, SLC6A9 with schizophrenia

    PubMed Central

    Deng, Xiangdong; Sagata, Noriaki; Takeuchi, Naoko; Tanaka, Masami; Ninomiya, Hideaki; Iwata, Nakao; Ozaki, Norio; Shibata, Hiroki; Fukumaki, Yasuyuki

    2008-01-01

    Background Based on the glutamatergic dysfunction hypothesis for schizophrenia pathogenesis, we have been performing systematic association studies of schizophrenia with the genes involved in glutametergic transmission. We report here association studies of schizophrenia with SLC1A4, SLC1A5 encoding neutral amino acid transporters ASCT1, ASCT2, and SLC6A5, SLC6A9 encoding glycine transporters GLYT2, GLYT1, respectively. Methods We initially tested the association of 21 single nucleotide polymorphisms (SNPs) distributed in the four gene regions with schizophrenia using 100 Japanese cases-control pairs and examined allele, genotype and haplotype association with schizophrenia. The observed nominal significance were examined in the full-size samples (400 cases and 420 controls). Results We observed nominally significant single-marker associations with schizophrenia in SNP2 (P = 0.021) and SNP3 (P = 0.029) of SLC1A4, SNP1 (P = 0.009) and SNP2 (P = 0.022) of SLC6A5. We also observed nominally significant haplotype associations with schizophrenia in the combinations of SNP2-SNP7 (P = 0.037) of SLC1A4 and SNP1-SNP4 (P = 0.043) of SLC6A5. We examined all of the nominal significance in the Full-size Sample Set, except one haplotype with insufficient LD. The significant association of SNP1 of SLC6A5 with schizophrenia was confirmed in the Full-size Sample Set (P = 0.018). Conclusion We concluded that at least one susceptibility locus for schizophrenia may be located within or nearby SLC6A5, whereas SLC1A4, SLC1A5 and SLC6A9 are unlikely to be major susceptibility genes for schizophrenia in the Japanese population. PMID:18638388

  12. Evaluation of approaches for identifying population informative markers from high density SNP Chips

    PubMed Central

    2011-01-01

    Background Genetic markers can be used to identify and verify the origin of individuals. Motivation for the inference of ancestry ranges from conservation genetics to forensic analysis. High density assays featuring Single Nucleotide Polymorphism (SNP) markers can be exploited to create a reduced panel containing the most informative markers for these purposes. The objectives of this study were to evaluate methods of marker selection and determine the minimum number of markers from the BovineSNP50 BeadChip required to verify the origin of individuals in European cattle breeds. Delta, Wright's FST, Weir & Cockerham's FST and PCA methods for population differentiation were compared. The level of informativeness of each SNP was estimated from the breed specific allele frequencies. Individual assignment analysis was performed using the ranked informative markers. Stringency levels were applied by log-likelihood ratio to assess the confidence of the assignment test. Results A 95% assignment success rate for the 384 individually genotyped animals was achieved with < 80, < 100, < 140 and < 200 SNP markers (with increasing stringency threshold levels) across all the examined methods for marker selection. No further gain in power of assignment was achieved by sampling in excess of 200 SNP markers. The marker selection method that required the lowest number of SNP markers to verify the animal's breed origin was Wright's FST (60 to 140 SNPs depending on the chosen degree of confidence). Certain breeds required fewer markers (< 100) to achieve 100% assignment success. In contrast, closely related breeds require more markers (~200) to achieve > 95% assignment success. The power of assignment success, and therefore the number of SNP markers required, is dependent on the levels of genetic heterogeneity and pool of samples considered. Conclusions While all SNP selection methods produced marker panels capable of breed identification, the power of assignment varied markedly among

  13. Quantitative trait locus analysis of body shape divergence in nine-spined sticklebacks based on high-density SNP-panel.

    PubMed

    Yang, Jing; Guo, Baocheng; Shikano, Takahito; Liu, Xiaolin; Merilä, Juha

    2016-01-01

    Heritable phenotypic differences between populations, caused by the selective effects of distinct environmental conditions, are of commonplace occurrence in nature. However, the actual genomic targets of this kind of selection are still poorly understood. We conducted a quantitative trait locus (QTL) mapping study to identify genomic regions responsible for morphometric differentiation between genetically and phenotypically divergent marine and freshwater nine-spined stickleback (Pungitius pungitius) populations. Using a dense panel of SNP-markers obtained by restriction site associated DNA sequencing of an F2 recombinant cross, we found 22 QTL that explained 3.5-12.9% of phenotypic variance in the traits under investigation. We detected one fairly large-effect (PVE = 9.6%) QTL for caudal peduncle length-a trait with a well-established adaptive function showing clear differentiation among marine and freshwater populations. We also identified two large-effect QTL for lateral plate numbers, which are different from the lateral plate QTL reported in earlier studies of this and related species. Hence, apart from identifying several large-effect QTL in shape traits showing adaptive differentiation in response to different environmental conditions, the results suggest intra- and interspecific heterogeneity in the genomic basis of lateral plate number variation. PMID:27226078

  14. Quantitative trait locus analysis of body shape divergence in nine-spined sticklebacks based on high-density SNP-panel

    PubMed Central

    Yang, Jing; Guo, Baocheng; Shikano, Takahito; Liu, Xiaolin; Merilä, Juha

    2016-01-01

    Heritable phenotypic differences between populations, caused by the selective effects of distinct environmental conditions, are of commonplace occurrence in nature. However, the actual genomic targets of this kind of selection are still poorly understood. We conducted a quantitative trait locus (QTL) mapping study to identify genomic regions responsible for morphometric differentiation between genetically and phenotypically divergent marine and freshwater nine-spined stickleback (Pungitius pungitius) populations. Using a dense panel of SNP-markers obtained by restriction site associated DNA sequencing of an F2 recombinant cross, we found 22 QTL that explained 3.5–12.9% of phenotypic variance in the traits under investigation. We detected one fairly large-effect (PVE = 9.6%) QTL for caudal peduncle length–a trait with a well-established adaptive function showing clear differentiation among marine and freshwater populations. We also identified two large-effect QTL for lateral plate numbers, which are different from the lateral plate QTL reported in earlier studies of this and related species. Hence, apart from identifying several large-effect QTL in shape traits showing adaptive differentiation in response to different environmental conditions, the results suggest intra- and interspecific heterogeneity in the genomic basis of lateral plate number variation. PMID:27226078

  15. A Microfluidic Device for Multiplex Single-Nucleotide Polymorphism Genotyping

    PubMed Central

    Zhu, Jing; Qiu, Chunmei; Palla, Mirkó; Nguyen, ThaiHuu; Russo, James J.; Ju, Jingyue; Lin, Qiao

    2015-01-01

    Single-nucleotide polymorphisms (SNPs) are the most abundant type of genetic variations; they provide the genetic fingerprint of individuals and are essential for genetic biomarker discoveries. Accurate detection of SNPs is of great significance for disease prevention, diagnosis and prognosis, and for prediction of drug response and clinical outcomes in patients. Nevertheless, conventional SNP genotyping methods are still limited by insufficient accuracy or labor-, time-, and resource-intensive procedures. Microfluidics has been increasingly utilized to improve efficiency; however, the currently available microfluidic genotyping systems still have shortcomings in accuracy, sensitivity, throughput and multiplexing capability. To address these challenges, we developed a multi-step SNP genotyping microfluidic device, which performs single-base extension of SNP specific primers and solid-phase purification of the extension products on a temperature-controlled chip. The products are ready for immediate detection by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), providing identification of the alleles at the target loci. The integrated device enables efficient and automated operation, while maintaining the high accuracy and sensitivity provided by MS. The multiplex genotyping capability was validated by performing rapid, accurate and simultaneous detection of 4 loci on a synthetic template. The microfluidic device has the potential to perform automatic, accurate, quantitative and high-throughput assays covering a broad spectrum of applications in biological and clinical research, drug development and forensics. PMID:26594354

  16. Single Nucleotide Polymorphism in Patients with Moyamoya Disease

    PubMed Central

    2015-01-01

    Moyamoya disease (MMD) is a chronic, progressive, cerebrovascular occlusive disorder that displays various clinical features and results in cerebral infarct or hemorrhagic stroke. Specific genes associated with the disease have not yet been identified, making identification of at-risk patients difficult before clinical manifestation. Familial MMD is not uncommon, with as many as 15% of MMD patients having a family history of the disease, suggesting a genetic etiology. Studies of single nucleotide polymorphisms (SNPs) in MMD have mostly focused on mechanical stress on vessels, endothelium, and the relationship to atherosclerosis. In this review, we discuss SNPs studies targeting the genetic etiology of MMD. Genetic analyses in familial MMD and genome-wide association studies represent promising strategies for elucidating the pathophysiology of this condition. This review also discusses future research directions, not only to offer new insights into the origin of MMD, but also to enhance our understanding of the genetic aspects of MMD. There have been several SNP studies of MMD. Current SNP studies suggest a genetic contribution to MMD, but further reliable and replicable data are needed. A large cohort or family-based design would be important. Modern SNP studies of MMD depend on novel genetic, experimental, and database methods that will hopefully hasten the arrival of a consensus conclusion. PMID:26180609

  17. Estimating population size using single-nucleotide polymorphism-based pedigree data.

    PubMed

    Spitzer, Robert; Norman, Anita J; Schneider, Michael; Spong, Göran

    2016-05-01

    Reliable population estimates are an important aspect of sustainable wildlife management and conservation but can be difficult to obtain for rare and elusive species. Here, we test a new census method based on pedigree reconstruction recently developed by Creel and Rosenblatt (2013). Using a panel of 96 single-nucleotide polymorphisms (SNPs), we genotyped fecal samples from two Swedish brown bear populations for pedigree reconstruction. Based on 433 genotypes from central Sweden (CS) and 265 from northern Sweden (NS), the population estimates (N = 630 for CS, N = 408 for NS) fell within the 95% CI of the official estimates. The precision and accuracy improved with increasing sampling intensity. Like genetic capture-mark-recapture methods, this method can be applied to data from a single sampling session. Pedigree reconstruction combined with noninvasive genetic sampling may thus augment population estimates, particularly for rare and elusive species for which sampling may be challenging. PMID:27096081

  18. Whole-Genome SNP Association in the Horse: Identification of a Deletion in Myosin Va Responsible for Lavender Foal Syndrome

    PubMed Central

    Brooks, Samantha A.; Gabreski, Nicole; Miller, Donald; Brisbin, Abra; Brown, Helen E.; Streeter, Cassandra; Mezey, Jason; Cook, Deborah; Antczak, Douglas F.

    2010-01-01

    Lavender Foal Syndrome (LFS) is a lethal inherited disease of horses with a suspected autosomal recessive mode of inheritance. LFS has been primarily diagnosed in a subgroup of the Arabian breed, the Egyptian Arabian horse. The condition is characterized by multiple neurological abnormalities and a dilute coat color. Candidate genes based on comparative phenotypes in mice and humans include the ras-associated protein RAB27a (RAB27A) and myosin Va (MYO5A). Here we report mapping of the locus responsible for LFS using a small set of 36 horses segregating for LFS. These horses were genotyped using a newly available single nucleotide polymorphism (SNP) chip containing 56,402 discriminatory elements. The whole genome scan identified an associated region containing these two functional candidate genes. Exon sequencing of the MYO5A gene from an affected foal revealed a single base deletion in exon 30 that changes the reading frame and introduces a premature stop codon. A PCR–based Restriction Fragment Length Polymorphism (PCR–RFLP) assay was designed and used to investigate the frequency of the mutant gene. All affected horses tested were homozygous for this mutation. Heterozygous carriers were detected in high frequency in families segregating for this trait, and the frequency of carriers in unrelated Egyptian Arabians was 10.3%. The mapping and discovery of the LFS mutation represents the first successful use of whole-genome SNP scanning in the horse for any trait. The RFLP assay can be used to assist breeders in avoiding carrier-to-carrier matings and thus in preventing the birth of affected foals. PMID:20419149

  19. A HapMap leads to a Capsicum annuum SNP infinium array: a new tool for pepper breeding

    PubMed Central

    Hulse-Kemp, Amanda M; Ashrafi, Hamid; Plieske, Joerg; Lemm, Jana; Stoffel, Kevin; Hill, Theresa; Luerssen, Hartmut; Pethiyagoda, Charit L; Lawley, Cindy T; Ganal, Martin W; Van Deynze, Allen

    2016-01-01

    The Capsicum genus (Pepper) is a part of the Solanacae family. It has been important in many cultures worldwide for its key nutritional components and uses as spices, medicines, ornamentals and vegetables. Worldwide population growth is associated with demand for more nutritionally valuable vegetables while contending with decreasing resources and available land. These conditions require increased efficiency in pepper breeding to deal with these imminent challenges. Through resequencing of inbred lines we have completed a valuable haplotype map (HapMap) for the pepper genome based on single-nucleotide polymorphisms (SNP). The identified SNPs were annotated and classified based on their gene annotation in the pepper draft genome sequence and phenotype of the sequenced inbred lines. A selection of one marker per gene model was utilized to create the PepperSNP16K array, which simultaneously genotyped 16 405 SNPs, of which 90.7% were found to be informative. A set of 84 inbred and hybrid lines and a mapping population of 90 interspecific F2 individuals were utilized to validate the array. Diversity analysis of the inbred lines shows a distinct separation of bell versus chile/hot pepper types and separates them into five distinct germplasm groups. The interspecific population created between Tabasco (C. frutescens chile type) and P4 (C. annuum blocky type) produced a linkage map with 5546 markers separated into 1361 bins on twelve 12 linkage groups representing 1392.3 cM. This publically available genotyping platform can be used to rapidly assess a large number of markers in a reproducible high-throughput manner for pepper. As a standardized tool for genetic analyses, the PepperSNP16K can be used worldwide to share findings and analyze QTLs for important traits leading to continued improvement of pepper for consumers. Data and information on the array are available through the Solanaceae Genomics Network. PMID:27602231

  20. A HapMap leads to a Capsicum annuum SNP infinium array: a new tool for pepper breeding.

    PubMed

    Hulse-Kemp, Amanda M; Ashrafi, Hamid; Plieske, Joerg; Lemm, Jana; Stoffel, Kevin; Hill, Theresa; Luerssen, Hartmut; Pethiyagoda, Charit L; Lawley, Cindy T; Ganal, Martin W; Van Deynze, Allen

    2016-01-01

    The Capsicum genus (Pepper) is a part of the Solanacae family. It has been important in many cultures worldwide for its key nutritional components and uses as spices, medicines, ornamentals and vegetables. Worldwide population growth is associated with demand for more nutritionally valuable vegetables while contending with decreasing resources and available land. These conditions require increased efficiency in pepper breeding to deal with these imminent challenges. Through resequencing of inbred lines we have completed a valuable haplotype map (HapMap) for the pepper genome based on single-nucleotide polymorphisms (SNP). The identified SNPs were annotated and classified based on their gene annotation in the pepper draft genome sequence and phenotype of the sequenced inbred lines. A selection of one marker per gene model was utilized to create the PepperSNP16K array, which simultaneously genotyped 16 405 SNPs, of which 90.7% were found to be informative. A set of 84 inbred and hybrid lines and a mapping population of 90 interspecific F2 individuals were utilized to validate the array. Diversity analysis of the inbred lines shows a distinct separation of bell versus chile/hot pepper types and separates them into five distinct germplasm groups. The interspecific population created between Tabasco (C. frutescens chile type) and P4 (C. annuum blocky type) produced a linkage map with 5546 markers separated into 1361 bins on twelve 12 linkage groups representing 1392.3 cM. This publically available genotyping platform can be used to rapidly assess a large number of markers in a reproducible high-throughput manner for pepper. As a standardized tool for genetic analyses, the PepperSNP16K can be used worldwide to share findings and analyze QTLs for important traits leading to continued improvement of pepper for consumers. Data and information on the array are available through the Solanaceae Genomics Network. PMID:27602231

  1. SNP Formation Bias in the Murine Genome Provides Evidence for Parallel Evolution.

    PubMed

    Plyler, Zackery E; Hill, Aubrey E; McAtee, Christopher W; Cui, Xiangqin; Moseley, Leah A; Sorscher, Eric J

    2015-09-01

    In this study, we show novel DNA motifs that promote single nucleotide polymorphism (SNP) formation and are conserved among exons, introns, and intergenic DNA from mice (Sanger Mouse Genomes Project), human genes (1000 Genomes), and tumor-specific somatic mutations (data from TCGA). We further characterize SNPs likely to be very recent in origin (i.e., formed in otherwise congenic mice) and show enrichment for both synonymous and parallel DNA variants occurring under circumstances not attributable to purifying selection. The findings provide insight regarding SNP contextual bias and eukaryotic codon usage as strategies that favor long-term exonic stability. The study also furnishes new information concerning rates of murine genomic evolution and features of DNA mutagenesis (at the time of SNP formation) that should be viewed as "adaptive." PMID:26253317

  2. [Genetic polymorphism of flax Linum usitatissimum based on use of molecular cytogenetic markers].

    PubMed

    Rachinskaia, O A; Lemesh, V A; Muravenko, O V; Iurkevich, O Iu; Guzenko, E V; Bol'sheva, N L; Bogdanova, M V; Samatadze, T E; Popov, K V; Malyshev, S V; Shostak, N G; Heller, K; Khotyleva, L V; Zelenin, A V

    2011-01-01

    Using a set of approaches based on the use of molecular cytogenetic markers (DAPI/C-banding, estimation of the total area of DAPI-positive regions in prophase nuclei, FISH with 26S and 5S rDNA probes) and the microsatellite (SSR-PCR) assay, we studied genomic polymorphism in 15 flax (Linum usitatissimum L.) varieties from different geographic regions belonging to three directions of selection (oil, fiber, and intermediate flaxes) and in the k-37 x Viking hybrid. All individual chromosomes have been identified in the karyotypes of these varieties on the basis of the patterns of differential DAPI/C-banding and the distribution of 26S and 5S rDNA, and idiograms of the chromosomes have been generated. Unlike the oil flax varieties, the chromosomes in the karyotypes of the fiber flax varieties have, as a rule, pericentromeric and telomeric DAPI-positive bands of smaller size, but contain larger intercalary regions. Two chromosomal rearrangements (chromosome 3 inversions) were discovered in the variety Luna and in the k-37 x Viking hybrid. In both these forms, no colocalization of 26S rDNA and 5S rDNA on the satellite chromosome was detected. The SSR assay with the use of 20 polymorphic pairs of primers revealed 22 polymorphic loci. Based on the SSR data, we analyzed genetic similarity of the flax forms studied and constructed a genetic similarity dendrogram. The genotypes studied here form three clusters. The oil varieties comprise an independent cluster. The genetically related fiber flax varieties Vita and Luna, as well as the landrace Lipinska XIII belonging to the intermediate type, proved to be closer to the oil varieties than the remaining fiber flax varieties. The results of the molecular chromosomal analysis in the fiber and oil flaxes confirm their very close genetic similarity. In spite of this, the combined use of the chromosomal and molecular markers has opened up unique possibilities for describing the genotypes of flax varieties and creating their genetic

  3. An Integrated SNP Mining and Utilization (ISMU) Pipeline for Next Generation Sequencing Data

    PubMed Central

    Azam, Sarwar; Rathore, Abhishek; Shah, Trushar M.; Telluri, Mohan; Amindala, BhanuPrakash; Ruperao, Pradeep; Katta, Mohan A. V. S. K.; Varshney, Rajeev K.

    2014-01-01

    Open source single nucleotide polymorphism (SNP) discovery pipelines for next generation sequencing data commonly requires working knowledge of command line interface, massive computational resources and expertise which is a daunting task for biologists. Further, the SNP information generated may not be readily used for downstream processes such as genotyping. Hence, a comprehensive pipeline has been developed by integrating several open source next generation sequencing (NGS) tools along with a graphical user interface called Integrated SNP Mining and Utilization (ISMU) for SNP discovery and their utilization by developing genotyping assays. The pipeline features functionalities such as pre-processing of raw data, integration of open source alignment tools (Bowtie2, BWA, Maq, NovoAlign and SOAP2), SNP prediction (SAMtools/SOAPsnp/CNS2snp and CbCC) methods and interfaces for developing genotyping assays. The pipeline outputs a list of high quality SNPs between all pairwise combinations of genotypes analyzed, in addition to the reference genome/sequence. Visualization tools (Tablet and Flapjack) integrated into the pipeline enable inspection of the alignment and errors, if any. The pipeline also provides a confidence score or polymorphism information content value with flanking sequences for identified SNPs in standard format required for developing marker genotyping (KASP and Golden Gate) assays. The pipeline enables users to process a range of NGS datasets such as whole genome re-sequencing, restriction site associated DNA sequencing and transcriptome sequencing data at a fast speed. The pipeline is very useful for plant genetics and breeding community with no computational expertise in order to discover SNPs and utilize in genomics, genetics and breeding studies. The pipeline has been parallelized to process huge datasets of next generation sequencing. It has been developed in Java language and is available at http://hpc.icrisat.cgiar.org/ISMU as a standalone

  4. Development of polymorphic microsatellite markers based on expressed sequence tags in Populus cathayana (Salicaceae).

    PubMed

    Tian, Z Z; Zhang, F Q; Cai, Z Y; Chen, S L

    2016-01-01

    Populus cathayana occupies a large area within the northern, central, and southwestern regions of China, and is considered to be an important reforestation species in western China. In order to investigate the population genetic structure of this species, 10 polymorphic microsatellite loci were identified based on expressed sequence tags from de novo sequencing on the Illumina HiSeq 2000 platform. All microsatellite primers were tested on 48 P. cathayana individuals from four locations on the Qinghai-Tibet Plateau. The observed heterozygosity ranged from 0.000 to 1.000, and the null-allele frequency ranged from 0.000 to 0.904. These microsatellite markers may be a useful tool in genetic studies on P. cathayana and closely related species. PMID:27525845

  5. A Locked Nucleic Acid Probe Based on Selective Salt-Induced Effect Detects Single Nucleotide Polymorphisms

    PubMed Central

    Zhang, Jing; Wu, Huizhe; Chen, Qiuchen; Zhao, Pengfei; Zhao, Haishan; Yao, Weifan; Wei, Minjie

    2015-01-01

    Detection of single based genetic mutation by using oligonucleotide probes is one of the common methods of detecting single nucleotide polymorphisms at known loci. In this paper, we demonstrated a hybridization system which included a buffer solution that produced selective salt-induced effect and a locked nucleic acid modified 12 nt oligonucleotide probe. The hybridization system is suitable for hybridization under room temperature. By using magnetic nanoparticles as carriers for PCR products, the SNPs (MDR1 C3435T/A) from 45 volunteers were analyzed, and the results were consistent with the results from pyrophosphoric acid sequencing. The method presented in this paper differs from the traditional method of using molecular beacons to detect SNPs in that it is suitable for research institutions lacking real-time quantitative PCR detecting systems, to detect PCR products at room temperature. PMID:26347880

  6. Using RNA-Seq to assemble a rose transcriptome with more than 13,000 full-length expressed genes and to develop the WagRhSNP 68k Axiom SNP array for rose (Rosa L.)

    PubMed Central

    Koning-Boucoiran, Carole F. S.; Esselink, G. Danny; Vukosavljev, Mirjana; van 't Westende, Wendy P. C.; Gitonga, Virginia W.; Krens, Frans A.; Voorrips, Roeland E.; van de Weg, W. Eric; Schulz, Dietmar; Debener, Thomas; Maliepaard, Chris; Arens, Paul; Smulders, Marinus J. M.

    2015-01-01

    In order to develop a versatile and large SNP array for rose, we set out to mine ESTs from diverse sets of rose germplasm. For this RNA-Seq libraries containing about 700 million reads were generated from tetraploid cut and garden roses using Illumina paired-end sequencing, and from diploid Rosa multiflora using 454 sequencing. Separate de novo assemblies were performed in order to identify single nucleotide polymorphisms (SNPs) within and between rose varieties. SNPs among tetraploid roses were selected for constructing a genotyping array that can be employed for genetic mapping and marker-trait association discovery in breeding programs based on tetraploid germplasm, both from cut roses and from garden roses. In total 68,893 SNPs were included on the WagRhSNP Axiom array. Next, an orthology-guided assembly was performed for the construction of a non-redundant rose transcriptome database. A total of 21,740 transcripts had significant hits with orthologous genes in the strawberry (Fragaria vesca L.) genome. Of these 13,390 appeared to contain the full-length coding regions. This newly established transcriptome resource adds considerably to the currently available sequence resources for the Rosaceae family in general and the genus Rosa in particular. PMID:25954285

  7. Using RNA-Seq to assemble a rose transcriptome with more than 13,000 full-length expressed genes and to develop the WagRhSNP 68k Axiom SNP array for rose (Rosa L.).

    PubMed

    Koning-Boucoiran, Carole F S; Esselink, G Danny; Vukosavljev, Mirjana; van 't Westende, Wendy P C; Gitonga, Virginia W; Krens, Frans A; Voorrips, Roeland E; van de Weg, W Eric; Schulz, Dietmar; Debener, Thomas; Maliepaard, Chris; Arens, Paul; Smulders, Marinus J M

    2015-01-01

    In order to develop a versatile and large SNP array for rose, we set out to mine ESTs from diverse sets of rose germplasm. For this RNA-Seq libraries containing about 700 million reads were generated from tetraploid cut and garden roses using Illumina paired-end sequencing, and from diploid Rosa multiflora using 454 sequencing. Separate de novo assemblies were performed in order to identify single nucleotide polymorphisms (SNPs) within and between rose varieties. SNPs among tetraploid roses were selected for constructing a genotyping array that can be employed for genetic mapping and marker-trait association discovery in breeding programs based on tetraploid germplasm, both from cut roses and from garden roses. In total 68,893 SNPs were included on the WagRhSNP Axiom array. Next, an orthology-guided assembly was performed for the construction of a non-redundant rose transcriptome database. A total of 21,740 transcripts had significant hits with orthologous genes in the strawberry (Fragaria vesca L.) genome. Of these 13,390 appeared to contain the full-length coding regions. This newly established transcriptome resource adds considerably to the currently available sequence resources for the Rosaceae family in general and the genus Rosa in particular. PMID:25954285

  8. Single Nucleotide Polymorphism of SREBF-1 Gene Associated with an Increased Risk of Endometrial Cancer in Chinese Women

    PubMed Central

    Dongol, Samina; Wang, Chenguang; Jiang, Jie

    2014-01-01

    Aim Elevated levels of sterol regulatory element-binding protein-1 (SREBP-1) have been found in endometrial cancer (EC), suggesting that it is essential to the development of EC. Obesity and diabetes have been established as known risk factors of EC, while SREBF-1 gene polymorphisms have also been found to be associated with obesity and type II diabetes. Therefore, we hypothesize that single nucleotide polymorphism (SNP) in SREBF-1 gene may be associated with increased risk of EC. Method We analyzed the sequence of SREBF-1 in tissue samples from 30 EC cases and 6 benign controls using high throughput method. Based on the primary results, we selected one SNP (rs2297508) as a genetic marker to conduct a hospital-based case-control study with 139 EC cases and 129 benign controls. The samples were examined under the microscope to determine their histopathology prior to the SNP analysis using RT-PCR. Results Through sequence analysis, we found 10 SNPs of SREBF-1 associated with EC, including 3 new SNPs. Fourteen percent of EC showed the rs2297508 SNP with C allele, while only 7% had the C allele was present in benign controls (p = 0.027, OR = 1.983). Additionally, the C allele was associated with cancer differentiation (p<0.05) and the depth of myometrial invasion (p<0.05). Conclusion Our study indicates that SNP (rs2297508) of SREBF-1 may serve as a genetic predisposition factor for the development of EC and screening of such genetic marker may be helpful in its early detection. PMID:24614076

  9. Single-nucleotide polymorphisms in base excision repair, nucleotide excision repair, and double strand break genes as markers for response to radiotherapy in patients with Stage I to II head-and-neck cancer

    SciTech Connect

    Carles, Joan . E-mail: jcarles@imas.imim.es; Monzo, Mariano; Amat, Marta; Jansa, Sonia; Artells, Rosa; Navarro, Alfons; Foro, Palmira; Alameda, Francesc; Gayete, Angel; Gel, Bernat; Miguel, Maribel; Albanell, Joan; Fabregat, Xavier

    2006-11-15

    Purpose: Polymorphisms in DNA repair genes can influence response to radiotherapy. We analyzed single-nucleotide polymorphisms (SNP) in nine DNA repair genes in 108 patients with head-and-neck cancer (HNSCC) who had received radiotherapy only. Methods and Materials: From May 1993 to December 2004, patients with Stage I and II histopathologically confirmed HNSCC underwent radiotherapy. DNA was obtained from paraffin-embedded tissue, and SNP analysis was performed using a real-time polymerase chain reaction allelic discrimination TaqMan assay with minor modifications. Results: Patients were 101 men (93.5%) and 7 (6.5%) women, with a median age of 64 years (range, 40 to 89 years). Of the patients, 76 (70.4%) patients were Stage I and 32 (29.6%) were Stage II. The XPF/ERCC1 SNP at codon 259 and XPG/ERCC5 at codon 46 emerged as significant predictors of progression (p 0.00005 and 0.049, respectively) and survival (p = 0.0089 and 0.0066, respectively). Similarly, when variant alleles of XPF/ERCC1, XPG/ERCC5 and XPA were examined in combination, a greater number of variant alleles was associated with shorter time to progression (p = 0.0003) and survival (p 0.0002). Conclusions: Genetic polymorphisms in XPF/ERCC1, XPG/ERCC5, and XPA may significantly influence response to radiotherapy; large studies are warranted to confirm their role in HNSCC.

  10. Development of Novel High-Resolution Melting-Based Assays for Genotyping Two Alu Insertion Polymorphisms (FXIIIB and PV92).

    PubMed

    González-Giraldo, Yeimy; Rodríguez-Dueñas, Marisol; Forero, Diego A

    2016-03-01

    Insertion/Deletion polymorphisms (InDels) are a common type of genetic variation, with a growing role in population genetics and applied genomics. There is the need for the development of novel cost-effective assays for genotyping InDels of high importance. The main objective of this study was to develop high-resolution melting-based assays for genotyping two commonly studied Alu insertion polymorphisms: FXIIIB and PV92 (rs70942849 and rs3138523). Three primers (two forward and one reverse) were designed for each marker, and high-resolution melting (HRM) analyses in a qPCR platform were performed, using EvaGreen fluorescent dye. For each one of the two Alu insertion polymorphisms, HRM analyses identified distinguishable peaks for the three genotypes, allowing a robust genotyping. Results were validated using 96 DNA samples previously genotyped and the assays worked with different DNA concentrations. In this study, we developed novel cost-effective assays, using qPCR, for genotyping two Alu insertion polymorphisms (widely used as ancestry markers). Our results highlight the feasibility of using HRM analyses for genotyping InDel polymorphisms of medical and biotechnological importance. PMID:26843017

  11. SNP discovery and chromosome anchoring provide the first physically-anchored hexaploid oat map and reveal synteny with model species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For the first time in many years a comprehensive genome map for cultivated oat has been constructed using a combination of single nucleotide polymorphism (SNP) markers and validated with a collection of cytogenetically defined germplasm lines. The markers were able to help distinguish the three geno...

  12. Translational genomics for abiotic stress in sorghum: transcriptional profiling and validation of SNP markers between germplasm with differential cold tolerance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One focus of the Sorghum Translational Genomics Lab (part of sorghum CRIS, PSGD, CSRL, USDA-ARS, Lubbock TX) is to utilize nucleotide variation between sorghum germplasm such as those derived from RNA seq for translation and validation of Single Nucleotide Polymorphism (SNP) into easy access DNA m...

  13. Utilization of a whole genome SNP panel for efficient genetic mapping in the mouse

    PubMed Central

    Moran, Jennifer L.; Bolton, Andrew D.; Tran, Pamela V.; Brown, Alison; Dwyer, Noelle D.; Manning, Danielle K.; Bjork, Bryan C.; Li, Cheng; Montgomery, Kate; Siepka, Sandra M.; Vitaterna, Martha Hotz; Takahashi, Joseph S.; Wiltshire, Tim; Kwiatkowski, David J.; Kucherlapati, Raju; Beier, David R.

    2006-01-01

    Phenotype-driven genetics can be used to create mouse models of human disease and birth defects. However, the utility of these mutant models is limited without identification of the causal gene. To facilitate genetic mapping, we developed a fixed single nucleotide polymorphism (SNP) panel of 394 SNPs as an alternative to analyses using simple sequence length polymorphism (SSLP) marker mapping. With the SNP panel, chromosomal locations for 22 monogenic mutants were identified. The average number of affected progeny genotyped for mapped monogenic mutations is nine. Map locations for several mutants have been obtained with as few as four affected progeny. The average size of genetic intervals obtained for these mutants is 43 Mb, with a range of 17–83 Mb. Thus, our SNP panel allows for identification of moderate resolution map position with small numbers of mice in a high-throughput manner. Importantly, the panel is suitable for mapping crosses from many inbred and wild-derived inbred strain combinations. The chromosomal localizations obtained with the SNP panel allow one to quickly distinguish between potentially novel loci or remutations in known genes, and facilitates fine mapping and positional cloning. By using this approach, we identified DNA sequence changes in two ethylnitrosourea-induced mutants. PMID:16461637

  14. Short communication: Relationship of call rate and accuracy of single nucleotide polymorphism genotypes in dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Call rate has been used as a measure of quality on both a single nucleotide polymorphism (SNP) and animal basis since SNP genotypes were first used in genomic evaluation of dairy cattle. The genotyping laboratories perform initial quality control screening and genotypes that fail are usually exclude...

  15. Calving traits of crossbred Brahman Cows are Associated with Heat Shock Protein 70 Genetic Polymorphisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objectives were to: 1) identify single nucleotide polymorphisms (SNP) located in the promoter region of the bovine heat shock protein 70 gene, and 2) evaluate associations between Hsp70 SNP and calving rates of Brahman-influenced cows. Specific primers were designed for PCR amplification of a 539 b...

  16. Association of Single Nucleotide Polymorphisms in the CAST Gene Associated with Longissimus Tenderness in Beef Cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective was to assess the association of single nucleotide polymorphisms (SNP) developed on the CAST gene, with longissimus tenderness. Forty one SNP were identified in the CAST gene and assays were developed. Markers were scattered throughout the gene. These markers, in conjunction with a com...

  17. Association of single nucleotide polymorphisms in candidate genes residing under quantitative trait loci in beef cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective was to assess the association of single nucleotide polymorphisms (SNP) developed on candidate genes residing under previously identified quantitative trait loci for marbling score and meat tenderness. Two hundred five SNP were identified on twenty candidate genes. Genes selected under ...

  18. Nuclear species-diagnostic SNP markers mined from 454 amplicon sequencing reveal admixture genomic structure of modern citrus varieties.

    PubMed

    Curk, Franck; Ancillo, Gema; Ollitrault, Frédérique; Perrier, Xavier; Jacquemoud-Collet, Jean-Pierre; Garcia-Lor, Andres; Navarro, Luis; Ollitrault, Patrick

    2015-01-01

    Most cultivated Citrus species originated from interspecific hybridisation between four ancestral taxa (C. reticulata, C. maxima, C. medica, and C. micrantha) with limited further interspecific recombination due to vegetative propagation. This evolution resulted in admixture genomes with frequent interspecific heterozygosity. Moreover, a major part of the phenotypic diversity of edible citrus results from the initial differentiation between these taxa. Deciphering the phylogenomic structure of citrus germplasm is therefore essential for an efficient utilization of citrus biodiversity in breeding schemes. The objective of this work was to develop a set of species-diagnostic single nucleotide polymorphism (SNP) markers for the four Citrus ancestral taxa covering the nine chromosomes, and to use these markers to infer the phylogenomic structure of secondary species and modern cultivars. Species-diagnostic SNPs were mined from 454 amplicon sequencing of 57 gene fragments from 26 genotypes of the four basic taxa. Of the 1,053 SNPs mined from 28,507 kb sequence, 273 were found to be highly diagnostic for a single basic taxon. Species-diagnostic SNP markers (105) were used to analyse the admixture structure of varieties and rootstocks. This revealed C. maxima introgressions in most of the old and in all recent selections of mandarins, and suggested that C. reticulata × C. maxima reticulation and introgression processes were important in edible mandarin domestication. The large range of phylogenomic constitutions between C. reticulata and C. maxima revealed in mandarins, tangelos, tangors, sweet oranges, sour oranges, grapefruits, and orangelos is favourable for genetic association studies based on phylogenomic structures of the germplasm. Inferred admixture structures were in agreement with previous hypotheses regarding the origin of several secondary species and also revealed the probable origin of several acid citrus varieties. The developed species-diagnostic SNP

  19. Nuclear Species-Diagnostic SNP Markers Mined from 454 Amplicon Sequencing Reveal Admixture Genomic Structure of Modern Citrus Varieties

    PubMed Central

    Curk, Franck; Ancillo, Gema; Ollitrault, Frédérique; Perrier, Xavier; Jacquemoud-Collet, Jean-Pierre; Garcia-Lor, Andres; Navarro, Luis; Ollitrault, Patrick

    2015-01-01

    Most cultivated Citrus species originated from interspecific hybridisation between four ancestral taxa (C. reticulata, C. maxima, C. medica, and C. micrantha) with limited further interspecific recombination due to vegetative propagation. This evolution resulted in admixture genomes with frequent interspecific heterozygosity. Moreover, a major part of the phenotypic diversity of edible citrus results from the initial differentiation between these taxa. Deciphering the phylogenomic structure of citrus germplasm is therefore essential for an efficient utilization of citrus biodiversity in breeding schemes. The objective of this work was to develop a set of species-diagnostic single nucleotide polymorphism (SNP) markers for the four Citrus ancestral taxa covering the nine chromosomes, and to use these markers to infer the phylogenomic structure of secondary species and modern cultivars. Species-diagnostic SNPs were mined from 454 amplicon sequencing of 57 gene fragments from 26 genotypes of the four basic taxa. Of the 1,053 SNPs mined from 28,507 kb sequence, 273 were found to be highly diagnostic for a single basic taxon. Species-diagnostic SNP markers (105) were used to analyse the admixture structure of varieties and rootstocks. This revealed C. maxima introgressions in most of the old and in all recent selections of mandarins, and suggested that C. reticulata × C. maxima reticulation and introgression processes were important in edible mandarin domestication. The large range of phylogenomic constitutions between C. reticulata and C. maxima revealed in mandarins, tangelos, tangors, sweet oranges, sour oranges, grapefruits, and orangelos is favourable for genetic association studies based on phylogenomic structures of the germplasm. Inferred admixture structures were in agreement with previous hypotheses regarding the origin of several secondary species and also revealed the probable origin of several acid citrus varieties. The developed species-diagnostic SNP

  20. Assessment of microsatellite and SNP markers for parentage assignment in ex situ African Penguin (Spheniscus demersus) populations.

    PubMed

    Labuschagne, Christiaan; Nupen, Lisa; Kotzé, Antoinette; Grobler, Paul J; Dalton, Desiré L

    2015-10-01

    Captive management of ex situ populations of endangered species is traditionally based on pedigree information derived from studbook data. However, molecular methods could provide a powerful set of complementary tools to verify studbook records and also contribute to improving the understanding of the genetic status of captive populations. Here, we compare the utility of single nucleotide polymorphisms (SNPs) and microsatellites (MS) and two analytical methods for assigning parentage in ten families of captive African penguins held in South African facilities. We found that SNPs performed better than microsatellites under both analytical frameworks, but a combination of all markers was most informative. A subset of combined SNP (n = 14) and MS loci (n = 10) provided robust assessments of parentage. Captive or supportive breeding programs will play an important role in future African penguin conservation efforts as a source of individuals for reintroduction. Cooperation among these captive facilities is essential to facilitate this process and improve management. This study provided us with a useful set of SNP and MS markers for parentage and relatedness testing among these captive populations. Further assessment of the utility of these markers over multiple (>3) generations and the incorporation of a larger variety of relationships among individuals (e.g., half-siblings or cousins) is strongly suggested. PMID:26819703

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

    PubMed Central

    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

  2. Exploring Germplasm Diversity to Understand the Domestication Process in Cicer spp. Using SNP and DArT Markers

    PubMed Central

    Roorkiwal, Manish; von Wettberg, Eric J.; Upadhyaya, Hari D.; Warschefsky, Emily; Rathore, Abhishek; Varshney, Rajeev K.

    2014-01-01

    To estimate genetic diversity within and between 10 interfertile Cicer species (94 genotypes) from the primary, secondary and tertiary gene pool, we analysed 5,257 DArT markers and 651 KASPar SNP markers. Based on successful allele calling in the tertiary gene pool, 2,763 DArT and 624 SNP markers that are polymorphic between genotypes from the gene pools were analyzed further. STRUCTURE analyses were consistent with 3 cultivated populations, representing kabuli, desi and pea-shaped seed types, with substantial admixture among these groups, while two wild populations were observed using DArT markers. AMOVA was used to partition variance among hierarchical sets of landraces and wild species at both the geographical and species level, with 61% of the variation found between species, and 39% within species. Molecular variance among the wild species was high (39%) compared to the variation present in cultivated material (10%). Observed heterozygosity was higher in wild species than the cultivated species for each linkage group. Our results support the Fertile Crescent both as the center of domestication and diversification of chickpea. The collection used in the present study covers all the three regions of historical chickpea cultivation, with the highest diversity in the Fertile Crescent region. Shared alleles between different gene pools suggest the possibility of gene flow among these species or incomplete lineage sorting and could indicate complicated patterns of divergence and fusion of wild chickpea taxa in the past. PMID:25010059

  3. Detection of Chromosomal Structural Alterations in Single Cells by SNP Arrays: A Systematic Survey of Amplification Bias and Optimized Workflow

    PubMed Central

    Iwamoto, Kazuya; Bundo, Miki; Ueda, Junko; Nakano, Yoko; Ukai, Wataru; Hashimoto, Eri; Saito, Toshikazu; Kato, Tadafumi

    2007-01-01

    Background In single-cell human genome analysis using whole-genome amplified product, a strong amplification bias involving allele dropout and preferential amplification hampers the quality of results. Using an oligonucleotide single nucleotide polymorphism (SNP) array, we systematically examined the nature of this amplification bias, including frequency, degree, and preference for genomic location, and we assessed the effects of this amplification bias on subsequent genotype and chromosomal copy number analyses. Methodology/Principal Findings We found a large variability in amplification bias among the amplified products obtained by multiple displacement amplification (MDA), and this bias had a severe effect on the genotype and chromosomal copy number analyses. We established optimal experimental conditions for pre-screening for high-quality amplified products, processing array data, and analyzing chromosomal structural alterations. Using this optimized protocol, we successfully detected previously unidentified chromosomal structural alterations in single cells from a lymphoblastoid cell line. These alterations were subsequently confirmed by karyotype analysis. In addition, we successfully obtained reproducible chromosomal copy number profiles of single cells from the cell line with a complex karyotype, indicating the applicability and potential of our optimized workflow. Conclusions/Significance Our results suggest that the quality of amplification products should be critically assessed before using them for genomic analyses. The method of MDA-based whole-genome amplification followed by SNP array analysis described here will be useful for exploring chromosomal alterations in single cells. PMID:18074030

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

    PubMed

    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

  5. Population-based analysis of the frequency of HFE gene polymorphisms: Correlation with the susceptibility to develop hereditary hemochromatosis

    PubMed Central

    KATSAROU, MARTHA-SPYRIDOULA; LATSI, ROSANA; PAPASAVVA, MARIA; DEMERTZIS, NIKOLAOS; KALOGRIDIS, THODORIS; TSATSAKIS, ARISTIDES M.; SPANDIDOS, DEMETRIOS A.; DRAKOULIS, NIKOLAOS

    2016-01-01

    Hereditary hemochromatosis (HH) is an autosomal recessive genetic disease, characterized by increased dietary iron absorption. Due to the absence of an effective excretory mechanism, the excess iron in the body may accumulate resulting in toxic effects. The HFE gene also affects the activity of hepcidin, a hormone which acts as a negative regulator of iron metabolism. In this study, we performed a population-based analysis of the distribution of three hemochromatosis-related polymorphisms in the HFE gene (rs1800562, rs1799945 and rs1800730). DNA from 1,446 non-related individuals of Greek ethnicity was collected and analyzed, either from whole blood or buccal swabs. The frequency distribution of these HFE gene polymorphisms was then determined. The results revealed that in our Greek population cohort (gr) the frequencies of each polymorphism were as follows: rs1800562: GG (wild-type)=97.0%, GA=1.5%, AA=1.5%; rs1799945: CC (wild-type)=74.4%, CG=23.4%, GG=2.2%; rs1800730: AA (wild-type)=98.1%, AT=1.5% and TT=0.4%. No association between the HFE polymorphisms rs1800562, rs1799945 and rs1800730 and gender could be established. As regards the rs1800562 polymorphism, the A allele (mutant) was ~1.8-fold more frequent in the European population (eur) than in the Greek population [(gr)=2,3%<(eur)=4%]. As for the rs1799945 polymorphism, the G allele (mutant) was 1.2-fold more frequent in the European population than in the Greek population [(gr)=13,9%<(eur)=17%]. As regards the rs1800730 polymorphism, the T allele (mutant) was ~1.7-fold more frequent in the European population than in the Greek population [(gr)=1.2%<(eur)=2%]. However, these pathogenic mutations were found more frequently in the Greek population compared to the global population (gl) [rs1800562: (gl)=1%<(gr)=2,3%; rs1799945: (gl)=7%<(gr)=13,9%; rs1800730: (gl)=<1%<(gr)=1.2%]. This suggests that the Greek population may differ genetically from the northern European population, due to influences from

  6. Conformational polymorphism in a Schiff-base macrocyclic organic ligand: an experimental and theoretical study.

    PubMed

    Lo Presti, Leonardo; Soave, Raffaella; Longhi, Mariangela; Ortoleva, Emanuele

    2010-10-01

    Polymorphism in the highly flexible organic Schiff-base macrocycle ligand 3,6,9,17,20,23-hexa-azapentacyclo(23.3.1.1(11,15).0(2,6).0(16,20))triaconta-1(29),9,11,13,15(30),23,25,27-octaene (DIEN, C(24)H(30)N(6)) has been studied by single-crystal X-ray diffraction and both solid-state and gas-phase density functional theory (DFT) calculations. In the literature, only solvated structures of the title compound are known. Two new polymorphs and a new solvated form of DIEN, all obtained from the same solvent with different crystallization conditions, are presented for the first time. They all have P\\bar 1 symmetry, with the macrocycle positioned on inversion centres. The two unsolvated polymorphic forms differ in the number of molecules in the asymmetric unit Z', density and cohesive energy. Theoretical results confirm that the most stable form is (II°), with Z' = 1.5. Two distinct molecular conformations have been found, named `endo' or `exo' according to the orientation of the imine N atoms, which can be directed towards the interior or the exterior of the macrocycle. The endo arrangement is ubiquitous in the solid state and is shared by two independent molecules which constitute an invariant supramolecular synthon in all the known crystal forms of DIEN. It is also the most stable arrangement in the gas phase. The exo form, on the other hand, appears only in phase (II°), which contains both the conformers. Similarities and differences among the occurring packing motifs, as well as solvent effects, are discussed with the aid of Hirshfeld surface fingerprint plots and correlated to the results of the energy analysis. A possible interconversion path in the gas phase between the endo and the exo conformers has been found by DFT calculations; it consists of a two-step mechanism with activation energies of the order of 30-40 kJ mol(-1). These findings have been related to the empirical evidence that the most stable phase (II°) is also the last appearing one, in

  7. Detection, validation and application of genotyping-by-sequencing based single nucleotide polymorphisms in upland cotton (Gossypium hirsutum L.).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence of two closely related sub-genomes in the allotetraploid Upland cotton (Gossypium hirsutum L.) combined with a narrow genetic base of the cultivated varieties has hindered the identification of polymorphic genetic markers and their utilization in improving this important crop. Genotypi...

  8. Association of "ADAM10" and "CAMK2A" Polymorphisms with Conduct Disorder: Evidence from Family-Based Studies

    ERIC Educational Resources Information Center

    Jian, Xue-Qiu; Wang, Ke-Sheng; Wu, Tie-Jian; Hillhouse, Joel J.; Mullersman, Jerald E.

    2011-01-01

    Twin and family studies have shown that genetic factors play a role in the development of conduct disorder (CD). The purpose of this study was to identify genetic variants associated with CD using a family-based association study. We used 4,720 single nucleotide polymorphisms (SNPs) from the Illumina Panel and 11,120 SNPs from the Affymetrix 10K…

  9. Epidemic population structure of extraintestinal pathogenic Escherichia coli determined by single nucleotide polymorphism pyrosequencing.

    PubMed

    Fernández-Romero, Natalia; Romero-Gómez, María Pilar; Gómez-Gil, María Rosa; Mingorance, Jesús

    2011-10-01

    We have developed an MLST-based scheme for typing Escherichia coli isolates using pyrosequencing of single nucleotide polymorphic positions (SNP). The SNP sequences are converted into allelic patterns and analyzed using the same approach used for MLST analyses. We have tested the method in two unselected collections of clinical isolates of E. coli obtained from blood and urine cultures. The two collections had a similar structure, 25% of the profiles (representing 68% of the isolates) were common to both, and 62% of the profiles (nearly 20% of the isolates) were unique. The four major profiles accounted for 44% of the isolates, and among these the most frequent one was related to the pandemic ST131 clone. The method is easy to implement and might be useful for typing large microbial collections. PMID:21723423

  10. Chemical Gradient-mediated Melting Curve Analysis for Genotyping of Single Nucleotide Polymorphisms

    PubMed Central

    Russom, Aman; Irimia, Daniel; Toner, Mehmet

    2009-01-01

    This report describes a microfluidic solid-phase Chemical Gradient-mediated Melting Curve Analysis (CGMCA) method for single nucleotide polymorphism (SNP) analysis. The method is based on allele-specific denaturation to discriminate mismatched (MM) from perfectly matched (PM) DNA duplexes upon exposure to linear chemical gradient. PM and MM DNA duplexes conjugated on beads are captured in a microfluidic gradient generator device designed with dams, keeping the beads trapped perpendicular to a gradient generating channel. Two denaturants, formamide and urea, were tested for their ability to destabilize the DNA duplex by competing with Watson-Crick pairing. Upon exposure to the chemical gradient, rapid denaturing profile was monitored in real time using fluorescence microscopy. The results show that the two duplexes exhibit different kinetics of denaturation profiles, enabling discrimination of MM from PM DNA duplexes to score SNP. PMID:19593749

  11. Novel single nucleotide polymorphism of UGT1A9 gene in Japanese.

    PubMed

    Fujita, Ken-ichi; Ando, Yuichi; Nagashima, Fumio; Yamamoto, Wataru; Endo, Hisashi; Kodama, Keiji; Araki, Kazuhiro; Miya, Toshimichi; Narabayashi, Masaru; Sasaki, Yasutsuna

    2006-02-01

    We sequenced from 5'-franking region to intron 1 (to 337 bp downstream from exon 1) of the UDP-glucuronosyltransferase (UGT) 1A9 gene prepared from 55 Japanese cancer patients. Seven single nucleotide polymorphisms (SNPs) were found. Two of them were UGT1A9 -118(T)n (n=10) and UGT1A9*5, and four were reported SNPs in intron 1 of UGT1A9 gene (89540C>T, 89549G>A, 89616T>A and 89710A>C). A novel SNP (89587T>C) was found. The sequence is as follows: SNP, 050824FujitaK001; Gene Name, UGT1A9; Accession Number, AF297093; Length, 25 bases; 5'-CCTTCTTGAAGAT/CATGTATTTATAA-3'. Two patients were heterozygous for the mutant allele, resulting in the allele frequency of 1.82%. PMID:16547398

  12. Polymorphous computing fabric

    DOEpatents

    Wolinski, Christophe Czeslaw; Gokhale, Maya B.; McCabe, Kevin Peter

    2011-01-18

    Fabric-based computing systems and methods are disclosed. A fabric-based computing system can include a polymorphous computing fabric that can be customized on a per application basis and a host processor in communication with said polymorphous computing fabric. The polymorphous computing fabric includes a cellular architecture that can be highly parameterized to enable a customized synthesis of fabric instances for a variety of enhanced application performances thereof. A global memory concept can also be included that provides the host processor random access to all variables and instructions associated with the polymorphous computing fabric.

  13. Nonsynonymous single nucleotide polymorphisms in the complement component 3 gene are associated with risk of age-related macular degeneration: a meta-analysis.

    PubMed

    Qian-Qian, Yu; Yong, Yao; Jing, Zhu; Xin, Bao; Tian-Hua, Xie; Chao, Sun; Jia, Cao

    2015-05-01

    Nonsynonymous single nucleotide polymorphisms (SNPs) in complement component 3 (CC3) are associated with the risk of age-related macular degeneration (AMD), however, this association is not consistent among studies. To thoroughly address this issue, we performed an updated meta-analysis to evaluate the association between nine SNPs in the CC3 gene and AMD risk. A search was conducted of the PubMed database through 3rd Aug, 2014. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of associations. Based on the search criteria for manuscripts reporting AMD susceptibility related to CC3 in nine SNPs, 57 case-control studies from 22 different articles were retrieved. Significantly positive associations were found for the rs2230199 C/G SNP and AMD in the Caucasian population, as well as for the rs1047286 C/T SNP. Moreover, a relationship between the rs11569536 G/A SNP and AMD was detected. By contrast, a negative association was observed between rs2250656 A/G SNP and AMD risk. The present meta-analysis suggests that these four SNPs in the CC3 gene are potentially associated with the risk of AMD development. Further studies using larger sample sizes and accounting for gene-environment interactions should be conducted to elucidate the role of CC3 gene polymorphisms in AMD risk. PMID:25688879

  14. Genome-Wide Joint Meta-Analysis of SNP and SNP-by-Smoking Interaction Identifies Novel Loci for Pulmonary Function

    PubMed Central

    Imboden, Medea; Koch, Beate; McArdle, Wendy L.; Smith, Albert V.; Smolonska, Joanna; Sood, Akshay; Tang, Wenbo; Wilk, Jemma B.; Zhai, Guangju; Zhao, Jing Hua; Aschard, Hugues; Burkart, Kristin M.; Curjuric, Ivan; Eijgelsheim, Mark; Elliott, Paul; Gu, Xiangjun; Harris, Tamara B.; Janson, Christer; Homuth, Georg; Hysi, Pirro G.; Liu, Jason Z.; Loehr, Laura R.; Lohman, Kurt; Loos, Ruth J. F.; Manning, Alisa K.; Marciante, Kristin D.; Obeidat, Ma'en; Postma, Dirkje S.; Aldrich, Melinda C.; Brusselle, Guy G.; Chen, Ting-hsu; Eiriksdottir, Gudny; Franceschini, Nora; Heinrich, Joachim; Rotter, Jerome I.; Wijmenga, Cisca; Williams, O. Dale; Bentley, Amy R.; Hofman, Albert; Laurie, Cathy C.; Lumley, Thomas; Morrison, Alanna C.; Joubert, Bonnie R.; Rivadeneira, Fernando; Couper, David J.; Kritchevsky, Stephen B.; Liu, Yongmei; Wjst, Matthias; Wain, Louise V.; Vonk, Judith M.; Uitterlinden, André G.; Rochat, Thierry; Rich, Stephen S.; Psaty, Bruce M.; O'Connor, George T.; North, Kari E.; Mirel, Daniel B.; Meibohm, Bernd; Launer, Lenore J.; Khaw, Kay-Tee; Hartikainen, Anna-Liisa; Hammond, Christopher J.; Gläser, Sven; Marchini, Jonathan; Kraft, Peter; Wareham, Nicholas J.; Völzke, Henry; Stricker, Bruno H. C.; Spector, Timothy D.; Probst-Hensch, Nicole M.; Jarvis, Deborah; Jarvelin, Marjo-Riitta; Heckbert, Susan R.; Gudnason, Vilmundur; Boezen, H. Marike; Barr, R. Graham; Cassano, Patricia A.; Strachan, David P.; Fornage, Myriam; Hall, Ian P.; Dupuis, Josée; Tobin, Martin D.; London, Stephanie J.

    2012-01-01

    Genome-wide association studies have identified numerous genetic loci for spirometic measures of pulmonary function, forced expiratory volume in one second (FEV1), and its ratio to forced vital capacity (FEV1/FVC). Given that cigarette smoking adversely affects pulmonary function, we conducted genome-wide joint meta-analyses (JMA) of single nucleotide polymorphism (SNP) and SNP-by-smoking (ever-smoking or pack-years) associations on FEV1 and FEV1/FVC across 19 studies (total N = 50,047). We identified three novel loci not previously associated with pulmonary function. SNPs in or near DNER (smallest PJMA = 5.00×10−11), HLA-DQB1 and HLA-DQA2 (smallest PJMA = 4.35×10−9), and KCNJ2 and SOX9 (smallest PJMA = 1.28×10−8) were associated with FEV1/FVC or FEV1 in meta-analysis models including SNP main effects, smoking main effects, and SNP-by-smoking (ever-smoking or pack-years) interaction. The HLA region has been widely implicated for autoimmune and lung phenotypes, unlike the other novel loci, which have not been widely implicated. We evaluated DNER, KCNJ2, and SOX9 and found them to be expressed in human lung tissue. DNER and SOX9 further showed evidence of differential expression in human airway epithelium in smokers compared to non-smokers. Our findings demonstrated that joint testing of SNP and SNP-by-environment interaction identified novel loci associated with complex traits that are missed when considering only the genetic main effects. PMID:23284291

  15. A 34K SNP genotyping array for Populus trichocarpa: design, application to the study of natural populations and transferability to other Populus species

    SciTech Connect

    Geraldes, Armando; Hannemann, Jan; Grassa, Chris; Farzaneh, Nima; Porth, Ilga; McKown, Athena; Skyba, Oleksandr; Li, Eryang; Mike, Fujita; Friedmann, Michael; Wasteneys, Geoffrey; Guy, Robert; El-Kassaby, Yousry; Mansfield, Shawn; Cronk, Quentin; Ehlting, Juergen; Douglas, Carl; DiFazio, Stephen P; Slavov, Gancho; Ranjan, Priya; Muchero, Wellington; Gunter, Lee E; Wymore, Ann; Tuskan, Gerald A; Martin, Joel; Schackwitz, Wendy; Pennacchio, Christa; Rokhsar, Daniel

    2013-01-01

    Genetic mapping of quantitative traits requires genotypic data for large numbers of markers in many individuals. Despite the declining costs of genotyping by sequencing, for most studies, the use of large SNP genotyping arrays still offers the most cost-effective solution for large-scale targeted genotyping. Here we report on the design and performance of a SNP genotyping array for Populus trichocarpa (black cottonwood). This genotyping array was designed with SNPs pre-ascertained in 34 wild accessions covering most of the species range. Due to the rapid decay of linkage disequilibrium in P. trichocarpa we adopted a candidate gene approach to the array design that resulted in the selection of 34,131 SNPs, the majority of which are located in, or within 2 kb, of 3,543 candidate genes. A subset of the SNPs (539) was selected based on patterns of variation among the SNP discovery accessions. We show that more than 95% of the loci produce high quality genotypes and that the genotyping error rate for these is likely below 2%, indicating that high-quality data are generated with this array. We demonstrate that even among small numbers of samples (n=10) from local populations over 84% of loci are polymorphic. We also tested the applicability of the array to other species in the genus and found that due to ascertainment bias the number of polymorphic loci decreases rapidly with genetic distance, with the largest numbers detected in other species in section Tacamahaca (P. balsamifera and P. angustifolia). Finally, we provide evidence for the utility of the array for intraspecific studies of genetic differentiation and for species assignment and the detection of natural hybrids.

  16. MULTINDELS-BOV: Zebu traceback method based on DNA insertion-deletion polymorphisms.

    PubMed

    Groenner-Penna, M; Croce, E F D; Pimenta, C G; Bicalho, H M S; Pena, S D J

    2014-01-01

    Brazil is a major producer and exporter of beef, with a herd of approximately 210 million animals. For the meat industry, a reliable animal traceback from its origin to the consumer market is paramount. Of all available identification systems, DNA is the only one that survives the slaughterhouse and reaches the dish of the consumer. DNA polymorphisms are already used for cattle traceback, but primarily for the subspecies Bos taurus taurus. However, in Brazil, another subspecies, B. taurus indicus predominates. We describe here the development of a DNA traceback method designed primarily for B. taurus indicus (Zebu), without leaving B. taurus taurus aside. We used insertion/deletion (indel) polymorphisms, which have the advantage of being simple and easily automatable, since in most cases, the variable loci are biallelic. We studied 94 indels, with a difference of two or more base pairs, in DNA pools of 60 Zebu and 60 taurine animals. A set of 22 indels with heterozygosity greater than 0.3 were selected and used to construct two multiplex PCRs. On the basis of the allelic frequency of these indels, the probability of random match was calculated to be 1.12 x 10(-8) for B. taurus indicus and 1.60 x 10(-6) for B. taurus taurus. Moreover, we estimated that an analysis would cost less than US$15.00 per animal. Thus, this system (MULTINDELS-BOV) is perfectly suited for building large genetic databases and offering viable prospects of a national system for cattle traceback DNA in Brazil. PMID:25501139

  17. Prediction Formulas for Individual Opioid Analgesic Requirements Based on Genetic Polymorphism Analyses

    PubMed Central

    Yoshida, Kaori; Nishizawa, Daisuke; Ichinomiya, Takashi; Ichinohe, Tatsuya; Hayashida, Masakazu; Fukuda, Ken-ichi; Ikeda, Kazutaka

    2015-01-01

    Background The analgesic efficacy of opioids is well known to vary widely among individuals, and various factors related to individual differences in opioid sensitivity have been identified. However, a prediction model to calculate appropriate opioid analgesic requirements has not yet been established. The present study sought to construct prediction formulas for individual opioid analgesic requirements based on genetic polymorphisms and clinical data from patients who underwent cosmetic orthognathic surgery and validate the utility of the prediction formulas in patients who underwent major open abdominal surgery. Methods To construct the prediction formulas, we performed multiple linear regression analyses using data from subjects who underwent cosmetic orthognathic surgery. The dependent variable was 24-h postoperative or perioperative fentanyl use, and the independent variables were age, gender, height, weight, pain perception latencies (PPL), and genotype data of five single-nucleotide polymorphisms (SNPs). To examine the utility of the prediction formulas, we performed simple linear regression analyses using subjects who underwent major open abdominal surgery. Actual 24-h postoperative or perioperative analgesic use and the predicted values that were calculated using the multiple regression equations were incorporated as dependent and independent variables, respectively. Results Multiple linear regression analyses showed that the four SNPs, PPL, and weight were retained as independent predictors of 24-h postoperative fentanyl use (R2 = 0.145, P = 5.66 × 10-10) and the two SNPs and weight were retained as independent predictors of perioperative fentanyl use (R2 = 0.185, P = 1.99 × 10-15). Simple linear regression analyses showed that the predicted values were retained as an independent predictor of actual 24-h postoperative analgesic use (R2 = 0.033, P = 0.030) and perioperative analgesic use (R2 = 0.100, P = 1.09 × 10-4), respectively. Conclusions We

  18. SNP Discovery with EST and NextGen Sequencing in Switchgrass (Panicum virgatum L.)

    PubMed Central

    Ersoz, Elhan S.; Wright, Mark H.; Pangilinan, Jasmyn L.; Sheehan, Moira J.; Tobias, Christian; Casler, Michael D.; Buckler, Edward S.; Costich, Denise E.

    2012-01-01

    Although yield trials for switchgrass (Panicum virgatum L.), a potentially high value biofuel feedstock crop, are currently underway throughout North America, the genetic tools for crop improvement in this species are still in the early stages of development. Identification of high-density molecular markers, such as single nucleotide polymorphisms (SNPs), that are amenable to high-throughput genotyping approaches, is the first step in a quantitative genetics study of this model biofuel crop species. We generated and sequenced expressed sequence tag (EST) libraries from thirteen diverse switchgrass cultivars representing both upland and lowland ecotypes, as well as tetraploid and octoploid genomes. We followed this with reduced genomic library preparation and massively parallel sequencing of the same samples using the Illumina Genome Analyzer technology platform. EST libraries were used to generate unigene clusters and establish a gene-space reference sequence, thus providing a framework for assembly of the short sequence reads. SNPs were identified utilizing these scaffolds. We used a custom software program for alignment and SNP detection and identified over 149,000 SNPs across the 13 short-read sequencing libraries (SRSLs). Approximately 25,000 additional SNPs were identified from the entire EST collection available for the species. This sequencing effort generated data that are suitable for marker development and for estimation of population genetic parameters, such as nucleotide diversity and linkage disequilibrium. Based on these data, we assessed the feasibility of genome wide association mapping and genomic selection applications in switchgrass. Overall, the SNP markers discovered in this study will help facilitate quantitative genetics experiments and greatly enhance breeding efforts that target improvement of key biofuel traits and development of new switchgrass cultivars. PMID:23049744

  19. Mining and Analysis of SNP in Response to Salinity Stress in Upland Cotton (Gossypium hirsutum L.)

    PubMed Central

    Wang, Xiaoge; Lu, Xuke; Wang, Junjuan; Wang, Delong; Yin, Zujun; Fan, Weili; Wang, Shuai; Ye, Wuwei

    2016-01-01

    Salinity stress is a major abiotic factor that affects crop output, and as a pioneer crop in saline and alkaline land, salt tolerance study of cotton is particularly important. In our experiment, four salt-tolerance varieties with different salt tolerance indexes including CRI35 (65.04%), Kanghuanwei164 (56.19%), Zhong9807 (55.20%) and CRI44 (50.50%), as well as four salt-sensitive cotton varieties including Hengmian3 (48.21%), GK50 (40.20%), Xinyan96-48 (34.90%), ZhongS9612 (24.80%) were used as the materials. These materials were divided into salt-tolerant group (ST) and salt-sensitive group (SS). Illumina Cotton SNP 70K Chip was used to detect SNP in different cotton varieties. SNPv (SNP variation of the same seedling pre- and after- salt stress) in different varieties were screened; polymorphic SNP and SNPr (SNP related to salt tolerance) were obtained. Annotation and analysis of these SNPs showed that (1) the induction efficiency of salinity stress on SNPv of cotton materials with different salt tolerance index was different, in which the induction efficiency on salt-sensitive materials was significantly higher than that on salt-tolerant materials. The induction of salt stress on SNPv was obviously biased. (2) SNPv induced by salt stress may be related to the methylation changes under salt stress. (3) SNPr may influence salt tolerance of plants by affecting the expression of salt-tolerance related genes. PMID:27355327

  20. Functional differences exist between TNFα promoters encoding the common -237G SNP and the rarer HLA-B*5701-linked A variant.

    PubMed

    Simpson, Peter D; Moysi, Eirini; Wicks, Kate; Sudan, Kritika; Rowland-Jones, Sarah L; McMichael, Andrew J; Knight, Julian; Gillespie, Geraldine M

    2012-01-01

    A large body of functional and epidemiological evidence have previously illustrated the impact of specific MHC class I subtypes on clinical outcome during HIV-1 infection, and these observations have recently been re-iterated in genome wide association studies (GWAS). Yet because of the complexities surrounding GWAS-based approaches and the lack of knowledge relating to the identity of rarer single nucleotide polymorphism (SNP) variants, it has proved difficult to discover independent causal variants associated with favourable immune control. This is especially true of the candidate variants within the HLA region where many of the recently proposed disease influencing SNPs appear to reflect linkage with 'protective' MHC class I alleles. Yet causal MHC-linked SNPs may exist but remain overlooked owing to the complexities associated with their identification. Here we focus on the ancestral TNFα promoter -237A variant (rs361525), shown historically to be in complete linkage disequilibrium with the 'protective' HLA-B*5701 allele. Many of the ancestral SNPs within the extended TNFα promoter have been associated with both autoimmune conditions and disease outcomes, however, the direct role of these variants on TNFα expression remains controversial. Yet, because of the important role played by TNFα in HIV-1 infection, and given the proximity of the -237 SNP to the core promoter, its location within a putative repressor region previously characterized in mice, and its disruption of a methylation-susceptible CpG dinucleotide motif, we chose to carefully evaluate its impact on TNFα production. Using a variety of approaches we now demonstrate that carriage of the A SNP is associated with lower TNFα production, via a mechanism not readily explained by promoter methylation nor the binding of transcription factors or repressors. We propose that the -237A variant could represent a minor causal SNP that additionally contributes to the HLA-B*5701-mediated 'protective' effect

  1. Detection of HER2 Gene Polymorphism in Breast Cancer: PCR Optimization Study.

    PubMed

    Budiarto, Bugi Ratno; Desriani

    2016-01-01

    Cancers are the most deadly diseases in the world and their incidences continue to increase over time. Particularly, breast cancer in females places 1(st) rank among other types of cancers in term of cancer cases (23%) and death incidence (14%). Recent findings support the correlation between (Ile)655(Val) SNP in the HER2 gene with breast cancer risk. Moreover, the (Ile)655(Val) HER2 gene polymorphism could be a predictive factor in a neoadjuvant therapy setting. Precise detection of the (Ile)655(Val) HER2 gene SNP in early breast cancer patients will be beneficial in designing the most suitable treatment and in increasing the efficacy of anticancer drugs. Here we develop a rapid and inexpensive method for (Ile)655(Val) SNP detection in the HER2 gene based on allele-specific PCR technology. Two forward primers and one common reverse primer were designed to anneal specifically either on the HER2 gene fragment containing the GG genotype or to the HER2 gene fragment containing the AA genotype where one of these primers had been added with poly-GC at 5' upstream. Moreover, to increase discrimination level, mismatch bases at the SNP site and the 3(rd) base of each forward primers from 3'end were added. To test the performance of the designed primers in discriminating a polymorphism and its annealing temperature, breast cancer specimen-derived genomic DNA (with GG genotype) and pGEM_HER2/AA (with AA genotype) were used as templates in the PCR reaction. The optimal annealing temperature for SNP detection was at 51.5°C as showed by the appearance of a 150 base pair (bp) band as AA genotype (pGEM_HER2/AA template), 116bp band as GG genotype (genomic DNA template), and both types of bands as AG genotype (mix of pGEM_HER2/AA and genomic DNA template). Allelic types of breast cancer patients were also determined using this optimized method compared to sanger sequencing. The 100% accordance was shown for all types of genotypes in both methods. The allele-specific PCR in this

  2. Genetic correlation of SOCS3 polymorphisms with infantile asthma: an evidence based on a case-control study

    PubMed Central

    Fang, Ying; Ren, Xiaoxia; Feng, Zhanwei

    2015-01-01

    Objective: In order to explore the relevance of SOCS3 gene polymorphisms with infantile asthma and provide evidence for the ethology of infantile asthma, we conducted this case-control study. Methods: A total of 273 children were enrolled for study in this article, including 119 children with asthma and 154 healthy controls frequency-matched with the former in sex and age. The genotyping of SOCS3 rs4969170, rs4969168 polymorphisms in all subjects were performed using TaqMan probe method. Odds ratio (OR) with 95% confidence interval (CI) was used to represent the association strength between SOCS3 polymorphisms and infantile asthma and calculated by χ² test which was conducted to check the Hardy-Weinberg equilibrium (HWE) in the control group. Results: The genotypes distributions of SOCS3 polymorphisms in controls conformed to HWE. Compared with GG/GA genotype in SOCS3 rs4969170, AA genotype obviously increased the susceptibility to asthma in children (OR=2.556, 95% CI=1.377-4.744) and A allele also made the same conclusion (OR=2.287, 95% CI=1.311-3.991). Differently in rs4969168, AG and AG/GG genotypes distributions had significant differences in two groups (P=0.036, 0.043). This two polymorphisms existed the linkage disequilibrium and the haplotype analysis showed that A-G and A-A haplotypes in rs4969170-rs4969168 increased 1.855 and 0.863 times risk of asthma development in children, respectively. Conclusions: A significant relevance involved in SOCS3 gene polymorphisms and infantile asthma development based on a Chinese Han population. PMID:26464723

  3. The association between IGF-1 polymorphisms and high myopia

    PubMed Central

    Zhang, Xiaoyu; Zhou, Xingtao; Qu, Xinhua

    2015-01-01

    Background: The potential association between IGF-1 polymorphisms and high myopia has been investigated in previous studies, but the actual relationship remains controversial. Accordingly, we conducted a meta-analysisincludingcase-control and cohort studies to assess the existing relationship between high myopia and IGF-1 polymorphisms. We searched MEDLINE, EMBASE, and OVID. Odds ratios (OR) with 95% confidence intervals (CI) were derived for single-nucleotide polymorphisms (SNPs) involved in the studies obtained from the retrospective database search. Analyses of heterogeneity, sensitivity, and publication bias were also conducted. The findings from this meta-analysis were based on approximately 2,187 high myopia cases and 1,183 controls, and were used to assess the association between three IGF-1 genetic polymorphisms (rs6214, rs12423791, and rs5742632) and high myopia risks. We investigated the association of the IGF-1 gene SNP rs6214, but no statistical association was observed in the resulting odds ratios (OR) in the allelic (OR = 1.06, 95% CI = 0.89-1.25), dominant (OR = 1.07, 95% CI = 0.90-1.27), or recessive models (OR = 1.06, 95% CI = 0.89-1.26), or in the homozygote (OR = 1.12, 95% CI = 0.91-1.38) and heterozygote comparisons (OR = 1.06, 95% CI = 0.88-1.27). Simultaneously, two other selected SNPs, rs12423791 and rs5742632, were also studied, but similarly, no statistical association existed between these polymorphisms and the risk of high myopia. In conclusions, no statistical association between IGF-1 polymorphisms (rs6214, rs12423791, and rs5742632) and the risk of high myopia was observed following the reported meta-analysis. PMID:26309715

  4. SNP-VISTA: An Interactive SNPs Visualization Tool

    SciTech Connect

    Shah, Nameeta; Teplitsky, Michael V.; Pennacchio, Len A.; Hugenholtz, Philip; Hamann, Bernd; Dubchak, Inna L.

    2005-07-05

    Recent advances in sequencing technologies promise better diagnostics for many diseases as well as better understanding of evolution of microbial populations. Single Nucleotide Polymorphisms(SNPs) are established genetic markers that aid in the identification of loci affecting quantitative traits and/or disease in a wide variety of eukaryotic species. With today's technological capabilities, it is possible to re-sequence a large set of appropriate candidate genes in individuals with a given disease and then screen for causative mutations.In addition, SNPs have been used extensively in efforts to study the evolution of microbial populations, and the recent application of random shotgun sequencing to environmental samples makes possible more extensive SNP analysis of co-occurring and co-evolving microbial populations. The program is available at http://genome.lbl.gov/vista/snpvista.

  5. Analysis of genetic diversity and population structure in a tomato (Solanum lycopersicum L.) germplasm collection based on single nucleotide polymorphism markers.

    PubMed

    Wang, T; Zou, Q D; Qi, S Y; Wang, X F; Wu, Y Y; Liu, N; Zhang, Y M; Zhang, Z J; Li, H T

    2016-01-01

    Knowledge of genetic diversity is important to assist breeders in the selection of parental materials and in the design of breeding programs. In this study, we genotyped 348 inbred tomato lines, representing vintage and contemporary fresh-market varieties, by using 52 single nucleotide polymorphisms (SNPs); 45 of these were found to be polymorphic. The average minor allele frequency and unbiased expected heterozygosity were 0.315 and 0.356, respectively. Population structure analysis revealed that contemporary germplasm could be distinctly divided into six subpopulations representing three market classes and breeding programs (pink, green, and red). Vintage germplasm could be separated into at least two subpopulations, and more admixtures were found in vintage lines than in contemporary lines. These findings indicate that contemporary inbred lines are more diversified than vintage inbred lines. AMOVA of vintage and contemporary lines was performed. A significant difference was found (P < 0.01), which explained 17.4% of the total genetic variance. Subsequently, we constructed a core collection using 45 polymorphic SNP markers. The data showed that all alleles were captured by only 2% of lines, indicating that more alleles, as well as rare alleles, could enable more variation to be captured in the core collection. These data allow us to discard redundant inbred tomato lines and to select elite inbred lines, which will accelerate the breeding process. PMID:27525883

  6. Genome-wide SNP discovery in walnut with an AGSNP pipeline updated for SNP discovery in allogamous organisms

    PubMed Central

    2012-01-01

    Background A genome-wide set of single nucleotide polymorphisms (SNPs) is a valuable resource in genetic research and breeding and is usually developed by re-sequencing a genome. If a genome sequence is not available, an alternative strategy must be used. We previously reported the development of a pipeline (AGSNP) for genome-wide SNP discovery in coding sequences and other single-copy DNA without a complete genome sequence in self-pollinating (autogamous) plants. Here we updated this pipeline for SNP discovery in outcrossing (allogamous) species and demonstrated its efficacy in SNP discovery in walnut (Juglans regia L.). Results The first step in the original implementation of the AGSNP pipeline was the construction of a reference sequence and the identification of single-copy sequences in it. To identify single-copy sequences, multiple genome equivalents of short SOLiD reads of another individual were mapped to shallow genome coverage of long Sanger or Roche 454 reads making up the reference sequence. The relative depth of SOLiD reads was used to filter out repeated sequences from single-copy sequences in the reference sequence. The second step was a search for SNPs between SOLiD reads and the reference sequence. Polymorphism within the mapped SOLiD reads would have precluded SNP discovery; hence both individuals had to be homozygous. The AGSNP pipeline was updated here for using SOLiD or other type of short reads of a heterozygous individual for these two principal steps. A total of 32.6X walnut genome equivalents of SOLiD reads of vegetatively propagated walnut scion cultivar ‘Chandler’ were mapped to 48,661 ‘Chandler’ bacterial artificial chromosome (BAC) end sequences (BESs) produced by Sanger sequencing during the construction of a walnut physical map. A total of 22,799 putative SNPs were initially identified. A total of 6,000 Infinium II type SNPs evenly distributed along the walnut physical map were selected for the construction of an Infinium Bead

  7. Human leukocyte antigen-G allele polymorphisms have evolved following three different evolutionary lineages based on intron sequences.

    PubMed

    Cervera, Isabel; Herraiz, Miguel Angel; Peñaloza, Jorge; Barbolla, Maria Luz; Jurado, Maria Luisa; Macedo, Jacqueline; Vidart, José Antonio; Martinez-Laso, Jorge

    2010-11-01

    Human leukocyte antigen (HLA)-G alleles follow a different pattern of polymorphism generation from those of the HLA classical I alleles. These polymorphisms have been defined as a result of random permitted point mutations in exons. However, this polymorphism maintenance could have an evolutionary specific pathways based on noncoding regions as introns, 14-bp deletion/insertion (exon 8), or promoter regions. Therefore a systematic sequencing study of HLA-G alleles was done obtaining the complete genomic sequence of 16 different HLA-G alleles: nine alleles were intron and exon confirmatory sequences, four were exon confirmatory and new intron described sequences, and three were new alleles. A 14-bp deletion/insertion polymorphism was also sequenced in these alleles. These sequences, together with those previously published, were compared, and phylogenetic and molecular evolutionary analyses were performed. Results showed the presence of three major specific evolutionary patterns, tentatively named lineages, and the other four as minor lineages (only one allele). The relative age of the major lineages could also be established based on the number of lineage-specific positions and the number of alleles of each lineage. Two main mechanisms are clearly defined in the generation of the lineages (introns), gene conversion, and/or convergent evolution following specific patterns. PMID:20650296

  8. A molecular platform for the diagnosis of multidrug-resistant and pre-extensively drug-resistant tuberculosis based on single nucleotide polymorphism mutations present in Colombian isolates of Mycobacterium tuberculosis

    PubMed Central

    Martínez, Luz Maira Wintaco; Castro, Gloria Puerto; Guerrero, Martha Inírida

    2016-01-01

    Developing a fast, inexpensive, and specific test that reflects the mutations present in Mycobacterium tuberculosis isolates according to geographic region is the main challenge for drug-resistant tuberculosis (TB) control. The objective of this study was to develop a molecular platform to make a rapid diagnosis of multidrug-resistant (MDR) and extensively drug-resistant TB based on single nucleotide polymorphism (SNP) mutations present in therpoB, katG, inhA,ahpC, and gyrA genes from Colombian M. tuberculosis isolates. The amplification and sequencing of each target gene was performed. Capture oligonucleotides, which were tested before being used with isolates to assess the performance, were designed for wild type and mutated codons, and the platform was standardised based on the reverse hybridisation principle. This method was tested on DNA samples extracted from clinical isolates from 160 Colombian patients who were previously phenotypically and genotypically characterised as having susceptible or MDR M. tuberculosis. For our method, the kappa index of the sequencing results was 0,966, 0,825, 0,766, 0,740, and 0,625 forrpoB, katG, inhA,ahpC, and gyrA, respectively. Sensitivity and specificity were ranked between 90-100% compared with those of phenotypic drug susceptibility testing. Our assay helps to pave the way for implementation locally and for specifically adapted methods that can simultaneously detect drug resistance mutations to first and second-line drugs within a few hours. PMID:26841047

  9. Sensitive DNA detection and SNP discrimination using ultrabright SERS nanorattles and magnetic beads for malaria diagnostics.

    PubMed

    Ngo, Hoan T; Gandra, Naveen; Fales, Andrew M; Taylor, Steve M; Vo-Dinh, Tuan

    2016-07-15

    One of the major obstacles to implement nucleic acid-based molecular diagnostics at the point-of-care (POC) and in resource-limited settings is the lack of sensitive and practical DNA detection methods that can be seamlessly integrated into portable platforms. Herein we present a sensitive yet simple DNA detection method using a surface-enhanced Raman scattering (SERS) nanoplatform: the ultrabright SERS nanorattle. The method, referred to as the nanorattle-based method, involves sandwich hybridization of magnetic beads that are loaded with capture probes, target sequences, and ultrabright SERS nanorattles that are loaded with reporter probes. Upon hybridization, a magnet was applied to concentrate the hybridization sandwiches at a detection spot for SERS measurements. The ultrabright SERS nanorattles, composed of a core and a shell with resonance Raman reporters loaded in the gap space between the core and the shell, serve as SERS tags for signal detection. Using this method, a specific DNA sequence of the malaria parasite Plasmodium falciparum could be detected with a detection limit of approximately 100 attomoles. Single nucleotide polymorphism (SNP) discrimination of wild type malaria DNA and mutant malaria DNA, which confers resistance to artemisinin drugs, was also demonstrated. These test models demonstrate the molecular diagnostic potential of the nanorattle-based method to both detect and genotype infectious pathogens. Furthermore, the method's simplicity makes it a suitable candidate for integration into portable platforms for POC and in resource-limited settings applications. PMID:26913502

  10. A Study of Applicability of SNP Chips Developed for Bovine and Ovine Species to Whole-Genome Analysis of Reindeer Rangifer tarandus.

    PubMed

    Kharzinova, Veronika R; Sermyagin, Alexander A; Gladyr, Elena A; Okhlopkov, Innokentiy M; Brem, Gottfried;