Abstract

MC4R belongs to a seven-transmembrane G-protein-coupled receptor which may regulate body composition and insulin action. Many mutations in the MC4R gene are associated with obesity, energy expenditure and serum triglyceride levels in human and animals. Six mutations in the MC4R gene were identified in our study (-293 C>G, -193 A>T, -192 T>G, -129A>G, -84T>C and 1069C>G). The -129A>G was significantly associated with live weight (LW) (P<0.05); cattle with the genotypes AG and GG had higher LW than genotype AA. The 1069 C>G was significantly associated with live weight (LW), carcass weight (CW), back fat thickness (BFT) and marbling score (MS). Cattle with the genotype GG had higher LW, CW and MS than genotype CC; cattle with the genotypes GG and CG had higher MS than CC. The results suggested that -129 A>G and 1069 C>G SNP of the MC4R gene may be useful as a genetic marker for carcass and meat quality traits in Qinchuan cattle.

Key words: MC4R gene, polymorphism, meat quality, carcass traits, qinchuan cattle.