Molecular Characterization and Phylogeny Based Analysis of Intron I Sequence of Myostatin (MSTN) Gene in Iranian Makuei Sheep Breed

Myostatin (MSTN), a negative regulator of skeletal muscle development, acts as a potential candidate gene used to increase muscle mass. Likewise, sheep MSTN gene has an important role in meat production. MSTN is made up of 376 amino acids, and is synthesized as a precursor protein. To investigate the MSTN in Iranian native Makuei sheep, a polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) analysis was used. Genomic DNA was isolated from the blood samples. A 417-bp of MSTN intron I segment was amplified using locus-specific primers. Four SSCP patterns were identified and nucleotide sequencing of the Makuei sheep MSTN gene was done and registered in the NCBI GenBank with “KJ526625” number. Three novel single nucleotide polymorphisms (SNPs) were found in the samples. These SNPs are found in 224bp, 226bp and 242bp locations. Accordingly three substitutions (c.224C>T; c.226A>G; c.242G>T) were observed in the intron 1 region of MSTN gene. The effects of the observed SNPs on breeding values of some biometric traits were investigated and the substitution of c.226A>G was found to be associated with heart girth (HG) and leg circumference (LC). Phylogenetic analysis, based on the nucleotide sequences indicated similar evaluation with the GenBank reference sequences. It seems that the observed polymorphisms of the ovine MSTN gene are associated with HG and LC traits.