Identification of the Bovine Growth Hormone Gene and Alui Loci Polymorphism by PCR – RFLP Method

The aim of this study was detection of polymorphism in the bovine growth hormone gene using PCR – RFLP as an efficient method for genetic analysis of polymorphism. A polymorphic site of the growth hormone gene (AluI polymorphism) that results in an amino acid change at position 127 of the protein chain (leucine, L to valine, V) has been linked to differences in circulating metabolites and metabolic hormones and to milk yield traits. The growth hormone gene is a candidate gene for body weight and weight gain in cattle since it plays a fundamental role in growth regulation. The polymorphism of growth hormone gene was studied in a group of 58 bulls of Slovak spotted breed. A strategy employing PCR was used to amplify 428 bp products from blood samples. Digestion of PCR products with restriction enzyme AluI revealed two alleles: allele L was 265, 96, 51, 16 fragments and allele V was 265, 147 and 16. Three patterns were observed and with frequencies 0.404, 0.473 and 0.123 for LL, LV and VV, respectively. The frequency of alleles L was 0.6404 and V was 0.3596.