An isolation, polymorphism and trait association study ofbovine <i>GAD1</i> and <i>GAL</i> genes

Abstract

The type and frequency of bovine GAD1 and GAL alleles have not yet been studied in beef cattle. Initial, partial characterization of several polymorphism sites of GAD1 and GAL genes was reported, and association analyses with feed intake, growth and carcass traits were performed. There was a single nucleotide polymorphism (SNP) in the 533bp fragment of GAD1 (Accession no. DQ139316), and this fragment revealed a polymorphism Ssp I restriction site caused by a G/A transition, located in 3'-UTR. A polymorphism Pst I restriction site at 102 (A/G transition) and a polymorphism Bsh1236 I restriction site at 837 (C/G transition) in the 2816bp PCR fragment (Accession no. DQ146944) corresponding to the bovine GAL gene were also identified. One hundred and thirty eight unrelated cattle from four breeds (Simmental, Angus, Hereford and Crossed Simmental) were genotyped and their allele frequencies were determined. In a preliminary trait association study, significant associations of GAD1 SNP-409, GAL SNP-102 and SNP-837 were found with average daily feed intake (ADFI). GAD1 and GAL SNPs were found to be good candidates to be used in marker-assisted selection (MAS) for ADFI.

Keywords: Cattle, GAD1, GAL, polymorphisms, growth and feed intake, association analysis

South African Journal of Animal Science Vol. 36 (4) 2006: pp. 269-274