Identification of SNPs in MYOD gene family and their associations with carcass traits in cattle

Myogenic differentiation (MYOD) genes encode for skeletal muscle-specific transcription factors with highly conserved basic helix-loop-helix domain. These genes play key roles in growth and muscle development, and are therefore considered as candidate genes for meat production traits in farm animals. The objectives of this study were to investigate single nucleotide polymorphisms (SNPs) in four MYOD family genes and to evaluate whether these polymorphisms affected carcass traits in cattle. Initially, the SNPs were detected by PCR and sequencing, and they were confirmed by restriction fragment length polymorphism (RFLP) method. Fourteen SNPs (4 from MYOD1, 4 from MYOG, 3 from MYF5 and 3 from MYF6) were identified in these genes, whereas 2 of them were missense mutations. Remarkable differences in allele frequencies were observed for the 6 selected SNPs among 7 different cattle breeds. The g.1274A > G and g.1911A > G SNP genotypes of MYOD1 and MYF5 genes, respectively, had significant associations with live weight and carcass weights in Korean cattle (P < 0.05). In addition, g.1111C > G polymorphism in MYOG gene approached significance for live weight (P = 0.08). The results presented here will give the valuable information for improving carcass traits in cattle.