POLYMORPHISM OF THE BOLA-DRB3 GENE AS A FACTOR OF RESISTANCE AND SUSCEPTIBILITY TO LEUKEMIA IN KALMYK CATTLE

It is known that animals identified with the BoLA DRB3 gene resistance do not develop leukemia, but they can be virus carriers. The resistance of heterozygous individuals to the BoLA DRB3 gene has been proven. Currently, studies on the BoLA DRB3 gene are insufficient in the breeds of the Turano-Mongolian group, and practically no studies have been conducted in the Kalmyk breed. One of the unique qualities of the breed is considered to be its high resistance to infectious diseases, which is why research on the BoLA DRB3 gene in Kalmyk cattle is of particular interest. The polymorphism of the BoLA-DRB3 gene in 70 Kalmyk cattle was analyzed. The distribution pattern of BoLA-DRB3 alleles and genotypes associated with leukemia resistance in the study population has been determined. The diagram data on the frequency distribution of alleles of the BoLA DRB3 gene indicate a high frequency of the resistance allele *28, which is 0.120, so we can assume a high resistance to leukemia in the studied population of Kalmyk cattle. Analysis of the polymorphism of the BoLA-DRB3 gene in the Kalmyk population (n=70) revealed a high frequency of the resistance allele *28 (0.120). Alleles *8, *16, *24 are sensitive to leukemia in this group of animals (0.199). There are differences in the proportion of genotypes, so the proportion of "leukemia resistance genotypes" is higher than the proportion of "leukemia sensitivity genotypes". The frequency of leukemia resistance alleles is high, equal to 0.171. Thus, the research results revealed a high level of heterozygous individuals of Kalmyk animals, which has a positive effect on the hereditary predisposition of the Kalmyk population.