scholarly journals Development of a Multiplex Tandem PCR (MT-PCR) Assay for the Detection of Emerging SARS-CoV-2 Variants

Viruses ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2028
Author(s):  
Richard Hale ◽  
Peter Crowley ◽  
Samir Dervisevic ◽  
Lindsay Coupland ◽  
Penelope R. Cliff ◽  
...  

The emergence of variants of SARS-CoV-2 has created challenges for the testing infrastructure. Although large-scale genome sequencing of SARS-CoV-2 has facilitated hospital and public health responses, access to sequencing facilities globally is variable and turnaround times can be significant, so there is a requirement for rapid and cost-effective alternatives. Applying a polymerase chain reaction (PCR)-based single nucleotide polymorphism (SNP) approach enables rapid (<4 h) identification of SARS-CoV-2 lineages from nucleic acid extracts, through the presence or absence of a panel of defined of genomic polymorphisms. For example, the B.1.1.7 lineage (“UK”, “Alpha”, or “Kent” variant) is characterised by 23 mutations compared to the reference strain, and the most biologically significant of these are found in the S gene. We have developed a SARS-CoV-2 typing assay focused on five positions in the S gene (HV69/70, N501, K417, E484 and P681). This configuration can identify a range of variants, including all the “Variants of Concern” currently designated by national and international public health bodies. The panel has been evaluated using a range of clinical isolates and standardised control materials at four UK hospitals and shows excellent concordance with the known lineage information derived from full sequence analysis. The assay has a turnaround time of about three hours for a set of up to 24 samples and has been utilised to identify emerging variants in a clinical setting.

2018 ◽  
Author(s):  
Jaime A. Osorio-Guarín ◽  
Corey R. Quackenbush ◽  
Omar E. Cornejo

AbstractAs the source of chocolate, cacao has become one of the most important crops in the world. The identification of molecular markers to understand the demographic history, genetic diversity and population structure plays a pivotal role in cacao breeding programs. Here, we report the use of a modified genotyping-by-sequencing (GBS) approach for large-scale single nucleotide polymorphism (SNP) discovery and allele ancestry mapping. We identified 12,357 bi-allelic SNPs after filtering, of which, 7,009 variants were ancestry informative. The GBS approach proved to be rapid, cost-effective, and highly informative for ancestry assignment in this species.


2020 ◽  
Vol 9 (1) ◽  
pp. 67
Author(s):  
Seung-Min Yang ◽  
Jiwon Baek ◽  
Eiseul Kim ◽  
Hyeon-Be Kim ◽  
Seyoung Ko ◽  
...  

In recent years, Salmonella Infantis has become a predominant serovariant in clinical and poultry isolates, thereby imposing a substantial economic burden on both public health and the livestock industry. With the aim of coping with the steep increase in serovar Infantis prevalence, a polymerase chain reaction (PCR)-based rapid and accurate diagnostic assay was developed in this study through pangenome profiling of 60 Salmonella serovars. A gene marker, SIN_02055, was identified, which is present in the S. Infantis genome but not in the pangenome of the other serovars. Primers specific to SIN_02055 were used to accurately detect serovar Infantis, and to successfully differentiate Infantis from the other 59 serovars in real-time PCR with a R2 of 0.999 and an efficiency of 95.76%. The developed method was applied to 54 Salmonella strains belonging to eight dominant serovars, and distinguished Infantis from the other seven serovars with an accuracy of 100%. The diagnostic primer set also did not show false positive amplification with 32 strains from eight non-Salmonella bacterial species. This cost-effective and rapid method can be considered an alternative to the classic serotyping using antisera.


2019 ◽  
Vol 6 (2) ◽  
pp. 259
Author(s):  
Asep Gunawan ◽  
Ratna Sholatia Harahap ◽  
Kasita Listyarini ◽  
Cece Sumantri

ABSTRAK Karakteristik karkas dan sifat perlemakan pada daging domba dikontrol oleh banyak gen salah satunya gen DGAT1 (Diacylglycerol Acyltransferasel 1). Penelitian ini bertujuan mengidentifikasi SNP (Single Nucleotide Polymorphism) gen DGAT1 pada titik mutasi g.8539 C>T dan asosiasinya terhadap karakteristik karkas dan sifat perlemakan pada domba Indonesia. Total sampel domba yang digunakan sebanyak 150 buah terdiri dari 35 sampel domba compass agrinak (DCA), 36 sampel domba barbados cross (DBC), 41 sampel domba komposit garut (DKG), 20 sampel domba ekor gemuk (DEG), dan 18 sampel domba ekor tipis (DET). Karakteristik karkas dan sifat perlemakan diukur dari domba jantan berumur 10-12 bulan. Identifikasi keragaman DGAT1|ALuI dianalisis dengan metode PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism). Hasil keragaman gen DGAT1 bersifat polimorfik dalam DET dan DEG, sedangkan DCA, DBC, dan DKG bersifat monomorfik. Dua genotipe disebut CC dan  CT ditemukan dalam DET dan DEG. Titik mutasi gen DGAT1 berasosiasi (P<0.05) dengan karakteristik karkas, yaitu bobot dan panjang karkas. Selain itu, keragaman gen DGAT1 juga berasosiasi signifikan (P<0.05) dengan asam lemak jenuh, yaitu asam stearat (C18:0) dan asam arakidat (C20:0) dan asam lemak tak jenuh tunggal, yaitu asam oleat (C18:1n9c). Gen DGAT1 memiliki kontribusi dalam karakteristik karkas dan komposisi asam lemak pada domba.Kata Kunci: domba, gen DGAT1, karakteristik karkas, PCR-RFLP, sifat perlemakan                                                              ABSTRACT            Characteristic of carcass and fatness traits of sheep is regulated by many genes such as DGAT1 (Diacylglycerol Acyltransferasel 1) gene. The research was aimed to investigate SNP (Single Nucleotide Polymorphism) of DGAT1 and its association with characteristic of carcass and fatness traits in Indonesian sheep. A total sample of sheeps used 150 rams of 10–12 months consisted 35 samples of compas agrinak sheep (CAS), 36 of barbados cross (BCS), 41 of garut composite (GCS), 20  of javanese fat tailed (JFT), and 18 of javanese thin tailed (JTT). Identification variant of DGAT1|ALuI were performed by PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism). The results of polymorphism of DGAT1 were found in JTT and JFT. However, SNP of DGAT1 in CAS, BCS and GCS were monomorfic. Two genotype namely CC and CT were found in JTT and JFT populations. A SNP of the DGAT1 was associated (P<0.05) with characteristic of carcass, including weight and length of carcass. The variant of DGAT1 was associated too with saturated fatty acids (SFA) including stearic acid (C18:0) and arachidic acid (C20:0), and mono unsaturated fatty acid (MUFA) including oleic acid (C18:1n9c). The DGAT1 gene was contribute to characteristic carcass and fatty acid composition in sheep.Keywords: DGAT1 gene, characteristic carcass, fatness traits, PCR-RFLP, sheep


2021 ◽  
Vol 12 ◽  
Author(s):  
Lingli Li ◽  
Yingjun Zhang ◽  
Yong Zhang ◽  
Ming Li ◽  
Dengan Xu ◽  
...  

Preharvest sprouting (PHS) significantly reduces grain yield and quality. Identification of genetic loci for PHS resistance will facilitate breeding sprouting-resistant wheat cultivars. In this study, we constructed a genetic map comprising 1,702 non-redundant markers in a recombinant inbred line (RIL) population derived from cross Yangxiaomai/Zhongyou9507 using the wheat 15K single-nucleotide polymorphism (SNP) assay. Four quantitative trait loci (QTL) for germination index (GI), a major indicator of PHS, were identified, explaining 4.6–18.5% of the phenotypic variances. Resistance alleles of Qphs.caas-3AL, Qphs.caas-3DL, and Qphs.caas-7BL were from Yangxiaomai, and Zhongyou9507 contributed a resistance allele in Qphs.caas-4AL. No epistatic effects were detected among the QTL, and combined resistance alleles significantly increased PHS resistance. Sequencing and linkage mapping showed that Qphs.caas-3AL and Qphs.caas-3DL corresponded to grain color genes Tamyb10-A and Tamyb10-D, respectively, whereas Qphs.caas-4AL and Qphs.caas-7BL were probably new QTL for PHS. We further developed cost-effective, high-throughput kompetitive allele-specific PCR (KASP) markers tightly linked to Qphs.caas-4AL and Qphs.caas-7BL and validated their association with GI in a test panel of cultivars. The resistance alleles at the Qphs.caas-4AL and Qphs.caas-7BL loci were present in 72.2 and 16.5% cultivars, respectively, suggesting that the former might be subjected to positive selection in wheat breeding. The findings provide not only genetic resources for PHS resistance but also breeding tools for marker-assisted selection.


2018 ◽  
Vol 46 (5) ◽  
pp. 1801-1814 ◽  
Author(s):  
Mehir un Nisa Iqbal ◽  
Syed Amir Maqbool ◽  
Taseer Ahmed Khan

Objective The aim of this study was to determine whether a novel polymorphism ( Tru9I) in the low penetrance vitamin D receptor (VDR) gene is associated with risk of premenopausal breast cancer (BC). Methods This case-control study included 228 patients with BC and 503 healthy women living in Pakistan who were analyzed for the VDR Tru9I (rs757343) single nucleotide polymorphism. BC cases were histopathologically confirmed, and all healthy controls were age-matched with patients (age range, 20–45 years). DNA was extracted, and the polymerase chain reaction and restriction fragment length polymorphism assays were performed. Results The VDR Tru9I polymorphism was not significantly associated with premenopausal BC. However, the risk of BC was associated with the ‘uu’ genotype (odds ratio [OR], 1.141; 95% confidence interval [95% CI], 0.206–6.317). Further, mutant Tru9I was significantly associated with Grade IV carcinoma (OR, 5.36; 95% CI, 1.181–24.338). Conclusion The VDR Tru9I ‘uu’ genotype may increase the risk of premenopausal BC.


Sign in / Sign up

Export Citation Format

Share Document