Marker‐assisted selection for forelimb‐girdle muscular anomaly of Japanese Black cattle

Forelimb-girdle muscular anomaly is a hereditary disorder of Japanese Black cattle characterized by tremors and astasia caused by hypoplasia of the forelimb-girdle muscles. The locus responsible for this disorder has been mapped on a middle region of bovine chromosome 26. In this study, we applied marker-assisted selection to identify the carriers of this disorder. Four microsatellite markers, DIK4440, BM4505, MOK2602 and IDVGA-59, linked to the disorder locus were genotyped in 37 unaffected offspring of a carrier sire. Transmission of the mutant or wild-type allele of the disorder locus of the sire to the 37 offspring was determined by examining the haplotypes of these markers. The results showed that nine and 18 of the 37 animals possessed the paternally transmitted mutant and wild-type alleles, respectively, and therefore, the nine animals with the mutant allele were identified as carriers. We concluded that the marker-assisted selection using these four markers can be applied for the identification of the carriers of forelimb-girdle muscular anomaly of Japanese Black cattle.