Project description:Genotyping arrays are tools for high throughput genotyping, which is required in genome-wide association studies (GWAS). Since the first cucumber genome draft was reported, genetic maps were constructed mainly based on simple-sequence repeats (SSRs) or on combinations of SSRs and other sequence-related amplified polymorphism (SRAP). In this study we developed the first cucumber genotyping array which consisted of 32,864 single nucleotide polymorphisms (SNPs). These markers cover the cucumber genome every 2.1Kb and have parents/F1 hybridizations as a training set. The training set was validated with Fludigm technology and had 98% concordance. The application of the genotyping array was illustrated by constructed a genetic map of 600 cM in length based on recombinant inbred lines (RIL) population of a 9930XGy14 cross of which compromise of 11564 SNPs. The markers collinearity between the genetic map and genome references of the two parents estimated as R2=0.97. Moreover, this comparison supports a translocation in the beginning of chromosome 5 that occurred in the lineage of 9930 and Gy14 as well as local variation in the recombination rate. We also used the array to investigate the local allele frequencies along the cucumber genome and found specific region with segregation distortions. We believe that the genotyping array together with the training set would be a powerful tool in applications such as quantitative-trait loci (QTL) analysis and GWAS.
Project description:Proteomic genotyping is the use of genetically variant peptides (GVPs), detected in a forensic protein sample, to infer the genotype of corresponding non-synonymous SNP alleles in the donor’s genome. This process does not depend on the presence of accessible or useable DNA in a sample. This makes proteomic genotyping an attractive alternative for analysis of problematic forensic samples, such as hair shafts, degraded bones or teeth, fingermarks, or sexual assault evidence. To demonstrate the concept in hair shafts, we developed an optimized sample processing protocol that could be used with high effectiveness on single hairs. This allows us to determine if the detected profiles of genetically variant peptides are robust and result in a consistent profile of inferred SNP alleles regardless of the chemical or biological history of the sample. Several real world scenarios have been evaluated. Here we include a study of four European subjects that had both pigmented and non-pigmented (or gray and non-gray) hair shafts. We tested whether (a) protein profiles change as a result of the loss of pigmentation and (b) these changes were reflected in the inferred genotype derived from detection of genetically variant peptides. Using this information, we can determine whether the resulting GVP profiles are more dependent on the biological context of pigmentation status or the underlying genotype.
Project description:SNP genotyping was used to determine if the free living Highland Wild dogs of Papua, Indonesia are the ansestors of captive New Guinea Singing Dogs.
Project description:Genome-wide SNP genotyping array can genotyped SNP highthroughly. It can be used in many aspects, such as phylogeny relationships, genome-wide association studies, copy number identification.