INVESTIGATION OF GDF8 GENE PROMOTER IN IRANIAN SHEEP

Myostatin is a growth factor belonging to the TGFs superfamily. TGFs growth factors are active in the regulation of embryonic development and in tissue homeostasis in adults. Myostatin is a growth factor controlling proliferation of myoblasts in embryonic development. Mutations in coding sequences of the bovine myostatin (GDF8) gene lead to muscle hyperplasia suggesting its inhibitory function on myoblast proliferation. In bovines, loss of this gene activity has been associated with expression of the double-muscled phenotype observed in some European cattle breeds. Myostatin gene polymorphism has also been studied in sheep. Due to the role of the myostatin gene in muscle development, the objective of this study was to sequence the myostatin gene promoter and its probable mutations, which have the potential to alter myostatin gene expression. DNA from blood samples of fifteen Arabic and fifteen Kordi sheep were extracted and used to amplify a 1034bp fragment in the myostatin gene. Three mutations were observed in the myostatin gene promoter at positions 430, 450 and 530.