Characterization of 5′ Upstream Region and Investigation of TTTTA Deletion in 5′ UTR of Myostatin (MSTN) Gene in Indian Goat Breeds

Myostatin (MSTN) is a negative regulator of muscle growth and development. In the present study characterization of MSTN 5' upstream region and investigation of 5'UTR TTTTA deletion was carried out in seven different Indian goat breeds. An 1181 bp fragment of 5' upstream region of MSTN gene was PCR amplified, cloned, and sequenced. Nucleotide sequences of MSTN 5' upstream region exhibited a high degree (>99%) identity among Indian as well as non-Indian goat breeds. These sequences showed >96.8% and 94.8% sequence identity with those of sheep and cattle. In silico analysis of MSTN 5' upstream region using MatInspector program revealed the presence of three TATA boxes, six E-box motifs, one CAAT box, and other important putative regulatory elements. We identified 16 nucleotide substitutions in the 5' upstream region of Indian goat breeds. Screening for a polymorphic TTTTA deletion (Δ -10 to -6) in 5' UTR using DraI/PCR-RFLP assay revealed the presence of only two genotypes, namely, AA (deletion homozygotes; 0.95) and AB (heterozygotes; 0.05) among the Indian breeds. The mutant allele A is almost fixed (~0.98) among Indian goat breeds and consequently, we could not perform the association study of this deletion with growth traits.