Association study between g.16024A>G polymorphism of the FASN gene and milk production of Holstein cattle

Fatty acid synthase regulates the de novo biosynthesis of long chained fatty acids and is considered to be a potential candidate gene for fat content and fatty acids composition in milk. The objective of the study was to estimate the impact of FASN-16024 polymorphism on milk production in Holstein cows. This study determined the genetic structure of the analysed population of 1050 Holstein cows to possible relationships between genetic variants of FASN-16024 and average breeding values for traits of milk production. PCR-RFLP was used to identify genetic polymorphism for FASN16024. The following genotype distributions were observed: AA (2.38%), AG (30%), and GG (67.62%). The frequencies of alleles A and G were 17.38% and 82.62%, respectively. The positive effect of the FASN gene polymorphism on the yield of milk, protein, and fat in the milk of Holstein cows was observed. No effect of individual genotypes of FASN-16024 gene polymorphism on fat and protein percentage was observed. The analysis of FASN gene polymorphism showed that the AA genotype significantly increased the average breeding value of the yield of milk (P<0.05), compared to the GG genotype. At the same time, the genotypes AA and AG increase the breeding value for the yield of fat (P<0.05) and yield of protein (P<0.05) in kilograms compared to the GG genotype. Therefore, the FASN gene may be used as a potential genetic marker for milk production in Holstein cattle with an emphasis on further research.