Project description:BACKGROUND: Arrayed primer extension (APEX) is a microarray-based rapid minisequencing methodology that may have utility in 'personalized medicine' applications that involve genetic diagnostics of single nucleotide polymorphisms (SNPs). However, to date there have been few reports that objectively evaluate the assay completion rate, call rate and accuracy of APEX. We have further developed robust assay design, chemistry and analysis methodologies, and have sought to determine how effective APEX is in comparison to leading 'gold-standard' genotyping platforms. Our methods have been tested against industry-leading technologies in two blinded experiments based on Coriell DNA samples and SNP genotype data from the International HapMap Project. RESULTS: In the first experiment, we genotyped 50 SNPs across the entire 270 HapMap Coriell DNA sample set. For each Coriell sample, DNA template was amplified in a total of 7 multiplex PCRs prior to genotyping. We obtained good results for 41 of the SNPs, with 99.8% genotype concordance with HapMap data, at an automated call rate of 94.9% (not including the 9 failed SNPs). In the second experiment, involving modifications to the initial DNA amplification so that a single 50-plex PCR could be achieved, genotyping of the same 50 SNPs across each of 49 randomly chosen Coriell DNA samples allowed extremely robust 50-plex genotyping from as little as 5 ng of DNA, with 100% assay completion rate, 100% call rate and >99.9% accuracy. CONCLUSION: We have shown our methods to be effective for robust multiplex SNP genotyping using APEX, with 100% call rate and >99.9% accuracy. We believe that such methodology may be useful in future point-of-care clinical diagnostic applications where accuracy and call rate are both paramount.

| S-EPMC2266772 | biostudies-literature

Multiplex detection and SNP genotyping in a single fluorescence channel.

Project description: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.

| S-EPMC3260291 | biostudies-literature

Bambusa multiplex

Project description:Bambusa multiplex overview

| PRJNA399780 | ENA

Genotyping data for seven patients from three unrelated, consanguineous multiplex families that presented with combined immunodeficiency, and were found to harbour mutations in CARMIL2

Project description:Combined immunodeficiencies are a heterogeneous collection of primary immune disorders that exhibit defects in T cell development or function, along with impaired B cell activity even in light of normal B cell maturation. CARMIL2 (RLTPR) is a protein involved in cytoskeletal organization and cell migration which also plays a role in CD28 co-signaling of T cells. Mutations in this protein have recently been reported to cause a novel primary immunodeficiency disorder with variable phenotypic presentations. Here we deposit genotyping data for seven patients from three unrelated, consanguineous multiplex families that presented with dermatitis, eosophagitis and recurrent skin and chest infections with evidence of combined immunodeficiency. By using this genotyping data to perform autozygome-guided analysis, and coupling it with the results of whole exome sequencing, we uncovered two mutations not previously reported (p.R50T and p.L846Sfs) in CARMIL2.

2018-01-25 | E-MTAB-6440 | biostudies-arrayexpress

Next generation rare variant discovery in multiplex AD families

Project description:Next generation rare variant discovery in multiplex AD families

| PRJNA517200 | ENA

Epi4K: Whole Exome Sequencing in Multiplex Families and Pairs

Project description:Epi4K: Whole Exome Sequencing in Multiplex Families and Pairs

| PRJNA437686 | ENA

Next generation rare variant discovery in multiplex AD families

Project description:Next generation rare variant discovery in multiplex AD families

| PRJNA517199 | ENA