Association of the Melanocortin-3(Mc3r) Receptor Gene With Growth and Reproductive Traits in Mazandaran Indigenous Chicken

Melanocortin-3 receptor (mc3r) plays an important role in the central control of energy homeostasis, and several functional polymorphisms of this gene have been detected. we have studied mc3r as a candidate gene responsible for variation in economically important traits in the chicken. to determine the association between mc3r polymorphism and phenotypic variation, a total of 190 individuals from breeding station of mazandaran indigenous chicken was genotyped using a modi-fied pcr-rflp method. the association of growth and reproductive traits was studied using a gen-eralized linear model. the association analysis suggested a positive effect of genotype aa with av-erage egg weight at ages 28 (ew28), 30 (ew30) and 32 (ew32) weeks compared with the gg genotype (p< 0.05). the association results also showed a positive effect of genotype ag with aver-age egg weight at age 30 (ew30) weeks compared with the gg genotype (p<0.05). in addition, the breeding values of ag genotype for average egg weight at age 32 (ew32) weeks and average egg weight at ages 28 (ew28), 30 (ew30) and 32 (ew32) weeks were higher than the gg genotype (p< 0.05). the findings form a basis for further analysis of the relation between genetic variations in mc3r gene and economically important traits, and application of molecular markers in poultry breeding.