Single-nucleotide polymorphism frequency in a set of selected lines of bread wheat (Triticum aestivum L.)

Genome ◽  
2006 ◽  
Vol 49 (9) ◽  
pp. 1131-1139 ◽  
Author(s):  
Catherine Ravel ◽  
Sébastien Praud ◽  
Alain Murigneux ◽  
Aurélie Canaguier ◽  
Frédéric Sapet ◽  
...  

Information on single-nucleotide polymorphisms (SNPs) in hexaploid bread wheat is still scarce. The goal of this study was to detect SNPs in wheat and examine their frequency. Twenty-six bread wheat lines from different origins worldwide were used. Specific PCR-products were obtained from 21 genes and directly sequenced. SNPs were discovered from the alignment of these sequences. The overall sequence polymorphism observed in this sample appears to be low; 64 single-base polymorphisms were detected in ~21.5 kb (i.e., 1 SNP every 335 bp). The level of polymorphism is highly variable among the different genes studied. Fifty percent of the genes studied contained no sequence polymorphism, whereas most SNPs detected were located in only 2 genes. As expected, taking into account a synthetic line created with a wild Triticum tauschii parent increases the level of polymorphism (101 SNPs; 1 SNP every 212 bp). The detected SNPs are available at http://urgi.versailles.inra.fr/GnpSNP . Data on linkage disequilibrium (LD) are still preliminary. They showed a significant level of LD in the 2 most polymorphic genes. To conclude, the genome size of hexaploid wheat and its low level of polymorphism complicate SNP discovery in this species.

2002 ◽  
Vol 48 (12) ◽  
pp. 2124-2130 ◽  
Author(s):  
Rosa Santacroce ◽  
Antonia Ratti ◽  
Francesco Caroli ◽  
Barbara Foglieni ◽  
Alessandro Ferraris ◽  
...  

Abstract Background: Microelectronic DNA chip devices represent an emerging technology for genotyping. We developed methods for detection of single-nucleotide polymorphisms (SNPs) in clinically relevant genes. Methods: Primer pairs, with one containing a 5′-biotin group, were used to PCR-amplify the region encompassing the SNP to be interrogated. After denaturation, the biotinylated strand was electronically targeted to discrete sites on streptavidin-coated gel pads surfaces by use of a Nanogen Molecular Workstation. Allele-specific dye-labeled oligonucleotide reporters were used for detection of wild-type and variant sequences. Methods were developed for SNPs in genes, including factor VII, β-globin, and the RET protooncogene. We genotyped 331 samples for five DNA variations in the factor VII gene, >600 samples from patients with β-thalassemia, and 15 samples for mutations within the RET protooncogene. All samples were previously typed by various methods, including DNA sequence analysis, allele-specific PCR, and/or restriction enzyme digestion of PCR products. Results: Analysis of amplified DNA required 4–6 h. After mismatched DNA was removed, signal-to-noise ratios were >5. More than 940 samples were typed with the microelectronic array platform, and results were totally concordant with results obtained previously by other genotyping methods. Conclusions: The described protocols detect SNPs of clinical interest with results comparable to those of other genotyping methods.


2019 ◽  
Vol 16 (2) ◽  
pp. 212-216
Author(s):  
M. K. Toporash ◽  
I. I. Motsnyy ◽  
A. Börner ◽  
P. Sourdille ◽  
S. V. Chebotar

Aim. The short arm of 1R rye (Secale cereale L.) chromosome is widely used in the breeding of bread wheat (Triticum aestivum L.), in particular 1RS.1BL, to introsgress genes of resistance to leaf (Lr26), stem (Sr31), striped (Yr9) rusts, as well as powdery mildew (Pm8); 1RS.1AL carries Gb2/Gb6 resistance genes to the wheat aphid (Schizaphis graminum Rondani), powdery mildew (Pm17), and the Cmc4 resistance gene to the Aceria tosichella Koifer mite, which is a vector for spreading of wheat mosaic virus. The aim of the research is to reveal molecular genetic polymorphisms of short arm rye 1RS chromosomes of different origins in bread wheat lines with 1RS.1BL translocation or 1R(1B) substitution from different sources. Methods. Genetic polymorphism of lines was analyzed by using PCR with a number of rye and wheat microsatellite markers. Results. It was shown that the CWXs line has a recombinant 1RS arm that contains the chromosomes parts of 1RS of the parental lines H242/97-2 and H273/97, due to crossover event, which led to the recombination of marked loci. Conclusions. Molecular genetic polymorphism has been reviled in 1RS.1BL translocations and 1R substituted rye chromosomes of different origins in H242/97-2, CWXs, H273/97, PavonMA1, Salmon lines, as there are different alleles present at loci: Xscm9, Xtsm422, Xgwm752, Xgwm18, Taglgap. Keywords: polymorphism, 1RS.1BL translocation, PCR analysis, microsatellites markers.


2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 37-37
Author(s):  
Andrea N DeCarlo ◽  
Keelee J McCarty ◽  
Sarah K Richey ◽  
Nathan Long ◽  
Scott Pratt

Abstract Detrimental effects to male reproductive physiology have been observed due to changes in prolactin (PRL) serum concentration. Regulation of PRL by dopamine binding to the dopamine type-2 receptor (DRD2) is well defined and associations between male physiology and single nucleotide polymorphisms (SNPs) within the DRD2 gene have been observed. The objective of the study was to evaluate association of a DRD2 SNP to PRL protein expression in bulls. Testis and epididymis were collected from bulls grazing a forage containing or lacking a dopamine agonist at the end of a 126 d study (n = 14). Bovine pituitaries (n = 587) were collected randomly over 3 mo from a local abattoir which processes cull cows and bulls. Sex of pituitaries was verified (n = 259 males) by duplex PCR for amplification of SRY and b-actin followed by Southern blotting of PCR products for selection of male. Prolactin protein expression was assessed in testis, epididymis, and pituitary by western blotting. Expression of PRL protein was below detection range in reproductive tissues but was present in pituitary, therefore experiments continued in pituitary. Restriction fragment length polymorphism genotyping was performed on pituitaries by amplification of the DRD2 SNP region followed by digestion with a Tfil enzyme. Digested of products produced 3,2, or 1 band (AG, AA, GG, respectively). A subset of male pituitaries was blotted by slot blot manifold and PRL protein expression assessed by immunodetection and densitometry analysis normalized to GAPDH expression. Pituitary genotype distribution was 17.4% AA (n = 16), 63% AG (n = 58), and 19.6% GG (n = 18). Prolactin protein expression in the pituitary was similar across genotype (P = 0.23). These findings indicate that the DRD2 SNP has no genotypic effect on PRL protein expression in bovine pituitary.


Genome ◽  
2006 ◽  
Vol 49 (7) ◽  
pp. 729-734 ◽  
Author(s):  
R C Leach ◽  
I S Dundas ◽  
A Houben

The physical length of the rye segment of a 4BS.4BL–5RL translocation derived from the Cornell Wheat Selection 82a1-2-4-7 in a Triticum aestivum 'Chinese Spring' background was measured using genomic in situ hybridization (GISH) and found to be 16% of the long arm. The size of this translocation was similar to previously published GISH measurements of another 4BS.4BL–5RL translocation in a Triticum aestivum 'Viking' wheat background. Molecular maps of both 4BS.4BL–5RL translocations for 2 different wheat backgrounds were developed using RFLP analysis. The locations of the translocation breakpoints of the 2 4BS.4BL–5RL translocations were similar even though they arose in different populations. This suggests a unique property of the region at or near the translocation breakpoint that could be associated with their similarity and spontaneous formation. These segments of rye chromosome 5 also contain a gene for copper efficiency that improves the wheat's ability to cope with low-copper soils. Genetic markers in these maps can also be used to screen for copper efficiency in bread wheat lines derived from the Cornell Wheat Selection 82a1 2-4-7.Key words: Triticum aestivum, wheat–rye translocation, homoeologous group 4, homoeologous group 5, GISH, comparative map, copper efficiency, hairy peduncle.


2018 ◽  
Vol 5 (1) ◽  
pp. 37-40
Author(s):  
Seri Mirianti Ishar ◽  
Jeyaganesan Pillay a/l Balaraman ◽  
Muhammad Jefri Mohd Yusof ◽  
Khairul Osman ◽  
Lee Loong Chuen

Human DNA consists of nucleus DNA (nDNA) and mitochondrial DNA (mtDNA). Both are valuable in medicine and forensic genetics but in this project, single nucleotide polymorphisms (SNPs) in mtDNA are used to trace the mutation occurred. Mutations in the sequence of alleles can lead to haplogroup variation and also certain diseases. The purpose of this study is to screen of mutations on alleles G709A, G3496T, and A3537G in Malay population of The National University of Malaysia (UKM) students. These SNPs lie in the ND1 (nitrogen dehydrogenase subunit 1) coding region, and the reports state that these three alleles are prone to mutate. From MitoMap Web site, the mutations of these alleles are reported to have potential in causing several diseases with the collaboration of other SNPs mutation. Allele G709A is reported to have an association with hearing loss and Leber Hereditary Optic Neuropathy (LHON) while allele G3496T is associated to LHON only. Allele A3537G is related to diabetes. A total of 100 DNA samples were collected from Malay students of UKM and preserved on FTA card to be purified later. The concentration of the DNA on the purified FTA card was between 10μM to 20μM. An attempt was made by amplifying those three loci from the genomic DNA. The amplified product was detected and separated using 1% gel electrophoresis. Before sequencing, the PCR products were visualized under UV light using gel documentation system. All PCR products were sequenced to detect the mutation on every single position chosen. From the alignment of sequencing results, allele G709A and allele G3496T showed no mutation. Meanwhile four samples from alleles A3537G has the mutation. From the results obtained, it seems that mutations are rare in all selected alleles. It is recommended to increase the sample size and alleles selected in the future to increase the strength of the study. This study also should be applied to other populations in Malaysia such as Chinese and Indian.  


2016 ◽  
Vol 10 (1) ◽  
pp. 37-41
Author(s):  
Fatima Abood Chaloob

Infection with hepatitis C virus (HCV) imposes a global challenge with over 180 million cases worldwide. Only few patients spontaneously had their virus neutralized, while most patients develop chronic HCV infection. This implies a key role of genetic factors in viral clearance or persistence. The current study aimed at clarifying the effect of certain single nucleotide polymorphisms (SNPs) on individual's susceptibility to HCV infection.  A total of 60 patients with confirmed HCV infection and 35 apparently healthy individuals were enrolled in this study. Blood sample was obtained from each participant, from which DNA was extracted. The JAK1gene was amplified with conventional PCR technique using three sets of primers targeting three SNPs in this gene: rs2780895, rs4244165 and rs17127024. Restriction fragment length polymorphism (RFLP) was used for genotyping of PCR products. Each of rs2780895 and rs17127024 had two genotypes in both patients and controls, however, only the heterozygous genotype of the SNP rs2780895 (CT) significantly associated with the susceptibility to HCV. The SNP rs4244165 appeared in only with homozygous wild genotype (GG) in both patients and controls. It can be concluded that allele T of the SNP rs2780895 could be considered as a risk factor for infection with HCV


2021 ◽  
Vol 12 ◽  
Author(s):  
Yongdun Xie ◽  
Weiwei Zeng ◽  
Chaojie Wang ◽  
Daxing Xu ◽  
Huijun Guo ◽  
...  

Stem elongation is a critical phase for yield determination and, as a major trait, is targeted for manipulation for improvement in bread wheat (Triticum aestivum L.). In a previous study, we characterized a mutant showing rapid stem elongation but with no effect on plant height at maturity. The present study aimed to finely map the underlying mutated gene, qd1, in this mutant. By analyzing an F2 segregating population consisting of 606 individuals, we found that the qd1 gene behaved in a dominant manner. Moreover, by using the bulked segregant RNA sequencing (BSR-seq)-based linkage analysis method, we initially mapped the qd1 gene to a 13.55 Mb region on chromosome 4B (from 15.41 to 28.96 Mb). This result was further confirmed in F2 and BC3F2 segregating populations. Furthermore, by using transcriptome sequencing data, we developed 14 Kompetitive Allele-Specific PCR (KASP) markers and then mapped the qd1 gene to a smaller and more precise 5.08 Mb interval from 26.80 to 31.88 Mb. To develop additional markers to finely map the qd1 gene, a total of 4,481 single-nucleotide polymorphisms (SNPs) within the 5.08 Mb interval were screened, and 25 KASP markers were developed based on 10x-depth genome resequencing data from both wild-type (WT) and mutant plants. The qd1 gene was finally mapped to a 1.33 Mb interval from 28.86 to 30.19 Mb on chromosome 4B. Four candidate genes were identified in this region. Among them, the expression pattern of only TraesCS4B02G042300 in the stems was concurrent with the stem development of the mutant and WT. The qd1 gene could be used in conjunction with molecular markers to manipulate stem development in the future.


2009 ◽  
Vol 49 (8) ◽  
pp. 675 ◽  
Author(s):  
N. L. Feeley ◽  
K. A. Munyard

The aim of this study was to determine if any correlation exists between melanocortin-1 receptor (MC1R) polymorphisms and skin and fibre colour in alpacas. Primers capable of amplifying the entire alpaca MC1R gene were designed from a comparative alignment of Bos taurus and Mus musculus MC1R gene sequences. The complete MC1R gene of 41 alpacas exhibiting a range of fibre colours, and which were sourced from farms across Australia, was sequenced from PCR products. Twenty-one single nucleotide polymorphisms were identified within MC1R. Two of these polymorphisms (A82G and C901T) have the potential to reduce eumelanin production by disrupting the activity of MC1R. No agreement was observed between fibre colour alone and MC1R genotype in the 41 animals in this study. However, when the animals were assigned to groups based on the presence or absence of eumelanin in their fibre and skin, only animals that had at least one allele with the A82/C901 combination expressed eumelanin. We propose that A82/C901 is the wild-type dominant ‘E’ MC1R allele, while alpacas with either G82/T901 or G82/Y901 are homozygous for the recessive ‘e’ MC1R allele and are therefore unable to produce eumelanin.


2001 ◽  
Vol 47 (8) ◽  
pp. 1373-1377 ◽  
Author(s):  
Tony M Hsu ◽  
Scott M Law ◽  
Shenghui Duan ◽  
Bruce P Neri ◽  
Pui-Yan Kwok

Abstract Background: The PCR-Invader® assay is a robust, homogeneous assay that has been shown to be highly sensitive and specific in genotyping single-nucleotide polymorphism (SNP) markers. In this study, we introduce two changes to improve the assay: (a) we streamline the PCR-Invader method by assaying both alleles for each SNP in one reaction; and (b) we reduce the cost of the method by adopting fluorescence polarization (FP) as the detection method. Methods: PCR product was incubated with Invader oligonucleotide and two primary probes at 93 °C for 5 min. Signal probes corresponding to the cleaved flaps of the primary probes [labeled with fluorescein and 6-carboxytetramethylrhodamine (TAMRA) dye] and Cleavase® VIII enzyme (a flap endonuclease) were then added to the mixture. This reaction mixture was incubated at 63 °C for 5 min. FP measurements were made with a fluorescence plate reader. Results: Eighty-eight individuals were genotyped across a panel of 10 SNPs, using PCR product as template, for a total of 880 genotypes. An average “no call” rate of 3.2% was observed after first round of experiments. PCR products were remade in those samples that failed to produce any genotype in the first round, and all gave clear-cut genotypes. When the genotypes determined by the PCR-Invader assay and template-directed dye-terminator incorporation assay with FP were compared, they were in 100% concordance for all SNP markers and experiments. Conclusions: The improvements introduced in this study make PCR-Invader assay simpler and more cost-effective, and therefore more suitable for high-throughput genotyping.


2020 ◽  
Vol 73 (2) ◽  
pp. 9131-9141
Author(s):  
Zine El Abidine Fellahi ◽  
Abderrahmane Hannachi ◽  
Hamenna Bouzerzour

This study aimed at evaluating the expected gains from selection obtained based upon direct, indirect, and index-based selection in a set of 599 bread wheat lines. The experiment was carried out at the experimental field of INRAA institute, Setif research unit (Algeria), in a Federer augmented block design including three controls. A wide range of genetic variability was observed among lines for the eleven traits assessed. The results indicated that index-based selection and selection based on grain yield expressed higher expected genetic gain than direct and indirect mono-trait-based selection. The best 15 selected lines exhibited higher grain yield than the control varieties, and they were clustered in three groups that contrasted mainly for the flag-leaf area, thousand-kernel weight, biomass, and harvest index. The index-based selection appears as a useful tool for the rapid selection of early filial generations, enriching selected breeding materials with desirable alleles and reducing the number of years required to combine these traits in elite varieties.


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