Allelic diversity of beta- and kappa-caseins in Holstein cattle of the Sverdlovsk region

Caseins are important components of milk that determine its texture, flavour and nutritional value. Milk protein polymorphism studies indicate that the B allele of beta-casein contributes to high quality milk, while the BB genotype of kappa-casein is associated with higher milk protein content, improved coagulation properties and higher yields of hard and semi-hard cheeses. In the present study, beta- and kappa-casein genotypes were determined on AGP Bovine 150K and Bovine 50K DNA chips in 523 and 607 individuals, respectively. The data obtained were tested for the Hardy-Weinberg law using Pearson’s concordance criterion. As a result, the prevalence of beta- and kappa-casein genotypes of Holstein cattle in the Sverdlovsk region was studied. The most common beta-casein genotypes were A1A2, A2A2 and A1A1, which account for 90% of the analysed herd. The AA, AB and AE kappa-casein genotypes accounted for more than 80% of the genotyped individuals, while the BB, BE and EE genotypes accounted for less than 20%. The results obtained are consistent with data from other regions.