Polymorphism in the GDF8 Gene and Their Effects on Carcass Traits in Lori-Bakhtiari and Zel Sheep Breeds

Myostatin (MSTN), known as growth and differentiation factor-8 (GDF8), is a member of the transforming growth factor beta (TGF-β) superfamily that acts as a negative regulator of muscle growth in mammals. The objective of this study was to check a part of the 5¢UTR, the first coding domain and part of intron-1 of MSTN gene, and the relationship among these segments with carcass traits via PCR-SSCP analysis. In marker site 1 (part of the 5¢UTR and exone 1), relationship between AB and AC, AB and AA getotypes with back fat thickness, AB and BB with dressing percentage without fat tail, AA and AC with blood triglyceride, AA and BB with blood cholesterol were significant. In Lori-Bakhtiari breed, relationship between AA and AC genotypes with fat tail weight, AB and BB genotypes with dressing percentage were significant. However, there was no relationship between genotypes of MSTN gene at marker site 1 with carcass weight with fat tail and carcass weight without fat tail. In intron-1 (marker site 2) Relationship between BD and CC genotypes with back fat thickness, AA and BD genotypes with cholesterol were significant.