Frequency of the Bovine Acyl-CoA:Diacylglycerol Acyltransferase 1 (DGAT1) K232A Polymorphism in Iranian Holstein Dairy Cattle
Because of the DGAT1 K232A polymorphism in the diversification of milk fat has been proven, This study were to assess the frequency of DGAT1 K232A polymorphism in Iranian Holstein dairy cows. Acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) , which is encoded by the DGAT1 gene, is a key enzyme in triacylglycerol synthesis in the mammary gland. The considered polymorphism results from AA→GC nucleotide substitution in DGAT1 gene exon 8 and so, alanine to lysine amino acid change at product protein. This polymorphism proved to significantly affect the percent fat content in milk. Genotyping population, was performed using RFLP-PCR technique. A 411 bp fragment including this polymorphism was amplified and digested with the enzyme CfrI to determine the genotypes of 408 Holstein cows.Three types genotype KK, KA and AA were detected. KK individuals have not mutatnt alles, KA individuals have one mutant allele and AA individual have twomutant alleles. Frequency of genetic AA, KA and KK genotypes were respectively 0/3578, 0.5515, and 0.0907 and frequency of K and A allels were estimated 0.37 and 0.63, respectively.
Keywords: DGAT1 gene, K232A polymorphism, RFLP-PCR, Iranian Holstein Cattle