Genetic Polymorphism of BoLA-DRB3.2 Locus in Ukrainian Cattle Breeds

The results of the study of BoLA-DRB3 gene polymorphism in four domestic breeds are presented: Ukrainian black-and-white dairy ( n = 293), Ukrainian red-and-white dairy ( n = 131), Gray Ukrainian ( n = 93), and Ukrainian white-headed ( n = 49). The allele frequencies were determined based on the analysis of restriction fragment length polymorphism of the products of amplification of BoLA-DRB3 gene exon 2. Genetic profiles of the breeds were formed according to the following indices: allele ( P a ) and genotype ( G a ) frequencies, observed ( H o ) and expected ( H e ) heterozygosity, Wright fixation index ( F IS ), total ( N a ) and effective ( A e ) number of alleles, and Shannon ( I ) and Pielou ( J ) efficiency indices. The maximal number of alleles were in the experimental sample of Ukrainian black-and-white dairy breed ( N a = 37). In Ukrainian red-and-white dairy, Ukrainian white-headed, and Gray Ukrainian breeds, 31, 29, and 28 variants were found, respectively. In two breeds, the alleles with “no established nomenclature” were typed: Gray Ukrainian, jba, *jab, *jbb, *nad and *nda; Ukrainian white-headed, *nab, *mdb, *iab, *gbb, *fbd, *naa; their portion was 8.9 and 7.1%, respectively. The portion of “informative” alleles was: Ukrainian black-and-white dairy, 55.8% (seven alleles); Ukrainian red-and-white dairy, 60.4% (six); Gray Ukrainian, 69.9% (four); Ukrainian white-headed, 65.3% (seven). The expected heterozygosity and Wright index had the following values: Ukrainian black-and-white dairy, H e = 0.942, F IS = 0.022; Ukrainian red-and-white dairy, H e = 0.93, F IS = 0.032; Gray Ukrainian, H e = 0.774, F IS = 0.041; Ukrainian white-headed, H e = 0.927, F IS = –0.035. According to biodiversity indices, the greatest variability is typical for the Ukrainian black-and-white dairy breed ( A e = 17.2; I = 3.13; J = 0.6). The Ukrainian white-headed ( A e = 13.7; I = 2.93; J = 0.61) and Ukrainian red-and-white dairy ( A e = 11.5; I = 2.87; J = 0.558) cattle also had a high level of variability. A low level of biodiversity was found in Gray Ukrainian breed ( A e = 4.42; I = 2.21; J = 0.455). The analysis of BoLA-DRB3 gene exon 2 polymorphism demonstrated that the greatest genetic diversity is typical for the Ukrainian black-and-while dairy breed. According to genetic distances, the domestic breeds are combined in a single cluster with Holsteins, which indicates their genetic relationship.