Molecular determination of the relationship between myostatin (MSTN) and insulin growth factor 2 (IGF-2) and growth characteristics in rabbits

This study investigates the effects of polymorphisms in the myostatin (MSTN) and insulin-like growth factor 2 (IGF2) gene on growth traits in rabbits. While the IGF2 gene was found to be monomorphic, the MSTN locus was identified as polymorphic. A mutation between cytosine and thymine was observed at position 847 in the second intron region of the MSTN gene, and genotypes TT and CT were attained. Genotype frequencies were calculated as 47% for TT and 53% for CT, while allele frequencies were determined as 74% for T and 26% for C. These genotype and allele frequencies were found to be consistent with Hardy-Weinberg equilibrium, with a χ² value of 7.27 (p<0.01). The research extensively analyzed the impact of MSTN gene polymorphism on important growth traits such as live weight, shoulder-to-tail length, front leg length, and chest circumference length. Rabbits with the TT genotype were found to have significantly higher live weight and front leg length compared to rabbits with the CT genotype, while rabbits with the CT genotype were found to be longer in shoulder-to-tail length and chest circumference length compared to rabbits with the TT genotype. No statistically significant difference was found among genotypes in other growth traits such as neck-shoulder length, hind leg length, and ear length. These findings suggest that MSTN gene polymorphism may influence certain growth traits in rabbits, and the observed genotypic differences, especially in traits such as live weight, shoulder-to-tail length, front leg length, and chest circumference length, should be considered as important factors in genetic breeding programs. This study provides crucial information to better understand the potential of MSTN gene polymorphisms in rabbit breeding programs and achieve desired phenotypic traits. Keywords: MSTN, IGF2, Polymorphism, Candidate Gene, Growth Traits