Analysis of variations in amino acid substitutions and microrna isolates of bovine leukemia virus

A number of studies have been carried out to investigate isolates of bovine leukosis virus in the Novosibirsk region. Within the framework of these studies, missense mutations, SNP substitutions and their influence on the type of infection course were studied. More than 700 samples were analyzed, of which full genomic sequencing of 48 samples was performed. A statistically significant relationship was found between the A(+187)C polymorphism in the activator sequence (DAS) region of the LTR (p value = 0.00737) and a high level of lymphocytosis. It was found that the (-4)G mutation in the CAP site can determine the type of course of the infectious process in virus-induced bovine leukemia. We found that G(-133)A/C mutations in CRE2 (46.7 %), C(+160)T in DAS (30 %) and A(310)del in BLV-mir-B4-5p, A(357)G in BLV-mir-B4-3p, A(462)G in BLV-mir-B5-5p and GA(497-498)AG in BLV-mir-B5-3p (26, 5 %) may influence the type of course of the infectious process in virus-induced bovine leukemia. Several polymorphisms in the genomic sequences of BLV isolates were identified, which open the understanding of the mechanisms of realization of virulent properties of bovine leukosis virus.