Affiliation:
1. Federal Scientific Center — All-Russian Research Institute of Experemental Veterinary Medicine named after K.I. Scryabyn and Y.R. Kovalenko of the Russian Academy of Sciences
Abstract
Relevance. The etiological agent in the development of persistent lymphocytosis and lymphosarcoma in cattle is Bovine leukemia virus. Phylogenetic analysis of sequenced nucleotide sequences of the BLV env-gene locus is the main, but not the only, approach to pathogen genotypic classification.Metods. The aim of the study was to identify single-nucleotide polymorphisms in the locus of the Bovine leukemia virus env-gene, considered as diagnostically significant for SNP genotyping of BLV based on the analysis of direct sequencing data of the PCR-product.Results. Alignment of the nucleotide sequences of the env-gene locus of 101 BLV type isolates of known Bovine leukemia virus genotypes revealed 155 single nucleotide polymorphisms, of which 35 SNP were considered diagnostically significant. At the same time, for BLV SNP-genotyping, an analysis of 22 characterized single nucleotide polymorphisms is sufficient, 14 of which are genotype-specific in relation to nine genotypes of the studied viral pathogen (C232G for the 3rd, G84A for the 4th, A117G, T326C and C412T — 5th, C394T — 8th, C40G — 9th, C132T — 10th, T113A and T256C — the 11th, T49C and G140A — the 12th, C83A and T304C — the 13th genotypes, thereby ensuring their identification. The other 8 characterized polymorphic positions are not genotype-specific, but the interpretation of the results of their detection has identification value in relation to the remaining 4 BLV genotypes: 1st (G205G and A337A), 2nd (T220C and A334G), 6th (A127R, C132C, T153C and C341C) and 7th (T220C and A334A) respectively.