NEWLY IDENTIFIED NUCLEOTIDE SUBSTITUTIONS IN BOVINE LEUKEMIA VIRUS ISOLATES FROM THE REPUBLIC OF BASHKORTOSTAN

The purpose of this paper is to study genetic properties of the causative agent of bovine leukemia, which persists in the territory of the Republic of Bashkortostan. PCR-RFLP and DNA sequencing methods were used for bovine leukemia virus (BLV) detection in biological material obtained from different age groups of cattle. The novelty of the research is that new knowledge has been obtained about the molecular genetic structure and the main polymorphisms of the causative agent of leukemia in animals on the territory of the Republic of Bashkortostan. For the first time, the classification of BLV isolates was carried out on the territory of the Republic using bioinformatic methods of statistical data processing. The dominant genetic groups were identified, and amino acid substitutions in the structure of the surface gp51 (SU) glycoprotein were evaluated. As a result of the cluster analysis, most of the sequences from the Republic of Bashkortostan were assigned to the genetic group BLV 4 (Belgian genotype according to the PDRF reaction). By bioinformatic processing, we determined single nucleotide SNP genotype-specific amino acid polymorphisms in the structure of the env gene of the studied BLV isolates, leading to amino acid changes in the structure of the SU gp51 shell glycoprotein, the main of which are located in its N-terminal part. The performed research expands scientific knowledge about genetic properties of individual genotypes of causative agent of leukemia. Epizootological and genetic screening makes it possible to study characteristics of the distribution of genetic types of BLV in different conditions and geographic territories of the Russian Federation. Studies took into account correlation with the course of the leukemic pathological process. That allows us to predict the possibility of the emergence of novel “aggressive” genetic variants of the BLV, interspecies transmission and timely develop modern methods for diagnosing and monitoring pathogen spread. EDN: FYDOJW