Association between Microsatellite DNA Marker of Leptin Gene and Carcass Traits in Korean Cattle

Leptin, the product of the obesity (ob) gene, is synthesized in adipocytes or fat cells and has been implicated in the regulation of food intake, energy balance and body composition in mammals. Therefore, the leptin gene could be a candidate gene controlling fat deposition, meat quality and carcass traits in cattle. In this study the micro satellite genotypes for leptin gene were determined and their effects on carcass traits and meat quality were estimated in Korean cattle. Six different micro satellite alleles within leptin gene were identified and gene frequencies of 173, 177, 184, 186, 190 and 192bp alleles were 0.012, 0.308, 0.067, 0.260, 0.342 and 0.016, respectively. The micro satellite marker of the leptin gene showed a significant association with the carcass percentage (CP) and marbling score (MS). Animals with genotypes 192/192 and 177/184 had higher CP than animals with other genotypes. Animals with genotypes 184/192 and 177/184 had higher MS compared with animals with other genotypes. Thus, the results suggest that the 177, 184 and 192bp alleles may be associated with increased carcass percentage and intramuscular fat levels. No associations were found between the micro satellite genotypes of the leptin gene and other carcass traits such as carcass weight (CW), backfat thickness (BF) and M. longissimus dorsi area (LDA). In conclusion, the micro satellite markers of the leptin gene may be useful for marker-assisted selection of carcass traits and meat quality in Korean cattle.