Genotyping of The FGD3 Gene in Japanese Black Cattle Bred in Oita Prefecture

Abstract

Two non-synonymous substitutions of the bovine FYVE, RhoGEF and PH domain containing 3 (FGD3) gene in Japanese Black cattle affect carcass weight in heterozygotes (normal/mutant) and the incidence of skeletal dysplasia in mutant homozygotes. Therefore, identifying the carrier status of FGD3 gene is important to prevent economic loss due to skeletal dysplasia and help improve the carcass weight in Japanese Black cattle. In this study, we developed a genotyping system using DigiTag2 assays. We assessed two non-synonymous substitution sites of FGD3 gene using five carrier heterozygous and three normal homozygous samples to investigate the carrier status of 169 Japanese Black cattle bred in Oita Prefecture. Our results demonstrated that the genotypes could be determined using this assay, i.e., all Japanese Black cattle examined were successfully genotyped for both sites. Both substitution sites were completely linked and among the 169 animals, 127 were normal homozygotes, 41 were carrier heterozygotes, and one was a mutant homozygote. The frequency of the mutant allele was 24.9% in this population.