Association of single nucleotide polymorphisms in the insulin and growth hormone gene with growth traits of Mia Chicken

This study was conducted in Mia chicken breed to evaluate the association between four single nucleotide polymorphisms (SNPs), in insulin (INS) and growth hormone (GH) genes, with growth traits. Three genotypes for the SNP A3971G of INS gene and the SNP G662A and C423T of GH gene were present in the population while only two genotypes were found in the Mia chicken breed for SNP T3737C of INS gene (TT and TC). The SNP T3737C INS gene and G662A GH gene had significant association with growth traits (P < 0.05). A significant association of T3737C INS gene with body weight (BW) was observed at 10 to 12 weeks of age and average daily gain (ADG) at 6–8 weeks of age. The SNP G662A of the GH gene was significantly associated (P < 0.05) with BW of Mia chicken at ages from 7 to 14 weeks and with ADG (4–6; 6–8; 8–10; 10–12 and 2–16 weeks). Chicken with the GG genotype had greater BW and ADG compared to the other genotypes. The results demonstrated that this SNP G662A GH gene may be used as a candidate marker gene for genetic improvement of growth traits in Mia chicken breed.