Detection of Dairy Cow Mammary Tissue DGAT1 Gene Single Nucleotide Polymorphisms Using Tetra-primers ARMS-PCR Method

This study was aimed to detect the single nucleotide polymorphisms of diacylgycerol acyltransferase 1 (DGAT1) K232A, and determine the DGAT1 genotype and milk traits of dairy cow, which would provide a new technique for marker-assisted selection in China Holstein dairy cows. In the present study, six Northern China Holstein dairy cows (three were lactating cows with high quatity milk and three were lactating cows with low quatity milk) were used to detect mammary tissue DGAT1 gene K232A polymorphisms. Genome DNA was extracted from each cow, a pair of external primers and a pair of internal primers were designed to amplify DGAT1 gene. The results showed that PCR-amplified fragments were 512 bp (external band), 369 bp (232K allele) and 181 bp (232A allele), respectively. The exterenal band functions as the internal PCR-positive control. The tetra-primer ARMS-PCR amplifications yielded a 512 bp fragment and a 181 bp fragment, indicating that the six dairy cows were all homozygous 232A. The results indicated that the tetra-primers ARMS-PCR was a quick and convenient method to identify dairy cow DGAT1 gene K232A polymorphisms, which was suitable for marker-assisted selection in China Holstein dairy cows.