Influence of the A286g Polymorphism in the Lepr Gene on Carcass Traits in a Paternal Broiler Line

Leptin plays a key role in the regulation of the energy balance in mammals. Thus, the leptin and leptin receptor are being intensively studied in these animals. However, it remains unclear whether the leptin-mediated control mechanism is conserved in nonmammalian vertebrates such as the avian. In this study, the association of the SNP LEPR A286G with carcass traits was investigated in the EMBRAPA TT Reference Population. A total of 1411 broilers was evaluated for 32 carcass traits. Association analyses were performed using QxPaK software with a model including fixed effects of sex, hatch and SNP, and the infinitesimal and residual random effects. Additive and dominance effects of the SNP were tested including their interaction with sex. The SNP showed significant association with carcass weight (P=0.54E-03), weights of head (P=0.28E-04), feet (P=0.41E-02), neck (P=0.44E-02), wings (P=0.20E-04), middle joint wings (P=0.27E-03), wing sticks (P=0.41E-03), thigh (P=0.11E-01), thigh muscle (P=0.12E-01), breast (P= 0.48E-04), breast muscle (P=0.18E-04), breast skin (P=0.43E01), breast fillet (P= 0.32E-03), back weight (P=0.19E-01), drumstick yield (P=0.28E01), breast muscle yield (P=0.11E-01), thigh and drumstick yield (P=0.95E-02), and thigh and drumstick muscle yield (P=0.72E-02). These associations are explained by the additive effect of the SNP. The results indicate that the LEPR SNP is a potential genetic marker to improve carcass traits in chickens.