Potential Consequences of DGAT2 and BTN Genes Polymorphism in Iraqi Holstein Cattle

This study was conducted to describe the genetic polymorphism within the bovine diacylglycerol acyltransferase 2 (DGAT2) gene and 5′-UTR of butyrophilin (BTN) gene by several in vitro tools, as well as to predict their consequences using several in silico tools. After withdrawing blood, extracting DNA, and designing specific polymerase chain reaction (PCR) primers, single-stranded conformation polymorphism (SSCP) and PCR experiments were performed. Each different SSCP set was sequenced and analyzed. Two genotypes were detected with two alleles. Concerning DGAT2, the AA genotype was the most common, and seven single nucleotide polymorphisms (SNPs) were found in the AB genotype while four SNPs were found in the AA genotype. The only coding SNP (p.Ala7Val) was found in the AB genotype. Concerning BTN, the AB genotype was the most common, and twenty-two novel SNPs were detected in the AB genotype, while six SNPs were observed in the AA genotype. The effect of the observed coding and noncoding SNPs was computationally analyzed. It was shown that the coding SNP, p.Ala7Val, was predicted to have functional consequences on the DGAT2 protein structure and function. Several outcomes were deduced from several noncoding SNPs in both genetic fragments studied. This study determines the pattern of polymorphism within the DGAT2 and BTN genes to conceive their consequences within Holstein breed.