Allelic Diversity of Calpastatin Gene in Sanjabi Sheep

Producing tender meat that consumer's desire is one of the major problems facing the sheep industry. Therefore, study of the biochemical mechanisms for muscle degradation is essential at the molecular level. Calpastatin is an endogenous inhibitor and plays an essential role in regulation of calpain activity in cells. Sanjabi sheep is an important animal producing meat in Kermanshah province that until now has not been studied by DNA markers, especially in the case of calpastatin gene. Therefore, present study was conducted to determine the genetic diversity of calpastatin gene in Sanjabi sheep and to compare this breed with other sheep breeds. A 622 bp fragment from this gene was amplified by polymerase chain reaction (PCR) from DNA samples of 142 Sanjabi sheep. PCR products were characterized by the restriction fragment length polymorphism (RFLP) method using two restriction enzymes, MspI, and NcoI, yielding 3 genotypes, MM, MN and NN. Genotype frequencies of MM, MN and NN were 0.67, 0.25 and 0.08, respectively. Gene frequencies of M and N were 0.79 and 0.21, respectively and mean of Nei's and Shanon's indexes were 0.51 and 0.33, respectively. Population was not in Hardy-Weinberg equilibrium for this locus. The results of this experiment indicated that this population is highly polymorphic. Furthermore, in the most studied Iranian sheep breeds, all 3 genotypes of this gene have not been detected whereas in this breed all 3 genotypes were observed.