Genotypes diversity of env gene of Bovine leukemia virus in Western Siberia

BACKGROUND: This study describes the biodiversity and properties of Bovine leukemia virus in Western Siberia. This paper explores the effect of different genotypes of the env gene of the cattle leukemia virus on hematological parameters of infected animals. The researchers focused on exploring the polymorphism of the env gene and, in doing so, discovered the new genotypes I(a) and I(b), which differ from genotype I. Several hypotheses on the origin of the different genotypes in Siberia are discussed. RESULTS: We obtained varying length of the restriction fragments for genotypes I(.) Additionally using restrictase Hae III were received fragments was named genotype I(a), and genotype I(b). There are 2.57 ± 0.55% (20 out of 779) samples of genotype I(b) which does not differ significantly from 1% (χ(2) = 2.46). Other genotypes were observed in the cattle of Siberia as wild type genotypes (their frequency varied from 17.84 to 32.73%). The maximum viral load was observed in animals with the II and IV viral genotypes (1000–1400 viral particles per 1000 healthy cells), and the minimum viral load was observed animals with genotype I(b) (from 700 to 900 viral particles per 1000 healthy cells). CONCLUSIONS: The probability of the direct introduction of genotype II from South America to Siberia is extremely small and it is more likely that the strain originated independently in an autonomous population with its distribution also occurring independently. A new variety of genotype I (I(b)) was found, which can be both a neoplasm and a relict strain.