The Comparison of CSN2 (rs43703011) Beta-Casein Gene Options Frequencies in Different Breeds of Ukraine Cows and the Prospect of Creating Herds with the A2/А2 Genotype

Abstract

Using real-time polymerase chain reaction methods, we have researched the CSN2 polymorphism (GenBank M55158; SNP rs43703011) gene in 4 breeds of cows in the North-East of Ukraine. The observed distributions of genotype frequencies А1/А1, А1/А2, А2/А2 and A1 or A2 alleles varies considerably in different cattle breeds: Lebedyn cattle - 14.6%, 31.7%, 53.7% (0.3 and 0.7); Ukrainian brown dairy breed - 6.8%, 43.2%, 50% (0.28 та 0.72); Simmental cattle - 7.3%, 51.2%, 41.5% (0.33 and 0.67); Ukrainian black speckled milky – 38.5%, 34.6%, 26.9% (0.56 та 0.44). The ratio of genotypes and alleles were found significant differences when comparing Lebedyn cattle and Simmental cattle (р=0.01), Lebedyn cattle and Ukrainian black speckled milky (р<0.0001), Lebedyn cattle compared to all other breeds (р=0.04), Ukrainian brown dairy breed and Ukrainian black speckled milky (р<0.0001), Ukrainian brown dairy breed compared to all other Ukrainian breeds (р=0.008); Simmental cattle and Ukrainian black speckled milky (р<0.0001), Simmental cattle (р=0.002) and Ukrainian black speckled milky (р<0.0001) to all other breeds. The obtained results indicate the prospects of breeding work to create herds with genotype A2/A2 animals - specifically with the Lebedyn cattle.

Overview of SNPs Associated with Trans Fat Content in Cow’s Milk

“…The functions of the genes used in the first approach have been somewhat studied in detail. The surface properties of casein micelles are highly dependent on beta-casein (CSN2), and rs43703011 is associated with A2 milk [33,34]. The statistical analysis showed that polymorphism of the CSN2 gene had a significant effect on the protein content in the milk of the Slovak Holstein cattle.…”