Breed differentiation of domestic pigs using SNP – extended bioinformatical analysis

Using the methods of bioinformatics, the analysis of data on sequencing of the genomes of individuals of the species Sus scrofa domesticus, which are located in the Sequence Read Archive (NCBI-SRA) database, was carried out. Genotypes were determined in silico for five breeds of domestic pigs – Duroc, Landrace, Pietrain, Large White and Yorkshire using an algorithm developed in the Python programming language. Based on a two-stage bioinformatics analysis, a wide range of SNPs with a high potential for differentiation was identified. The results obtained will be used to create express methods for determining the purity of pigs of these breeds. Extended bioinformatics analysis, which included genotyping by 7451 SNPs for 248 Sus scrofa domesticus genomes, revealed a total of 393 SNPs for all breeds for which there is a significant difference in the frequency of alternative alleles in Duroc, Landrace, Pietrain, Large White and Yorkshire pig breeds. Clusters within chromosomes are indicated, in which the density of SNPs with a high differentiating potential is the highest. For Duroc pigs, we identified 184 SNPs with differentiating potential, 24 of which showed a high differentiating potential, for Landrace pigs – 52 SNPs and 7, for Pietrain pigs – 39 and 9, for Large White pigs – 104 and 22, for Yorkshire pigs – 14 and 5, respectively.

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