Investigation of Leptin Gene Polymorphism in Iranian Native Cattle

Leptin, a peptide hormone secreted by adipose tissue cells, has been implicated in regulation of feed intake, energy balance, fertility, immune functions, and the neuroendocrine axis in rodents, humans and large domestic animals. The objective of present study was to determine the polymorphic patterns of leptin gene in Iranian native cattle using the PCR-RFLP technique. Bull semen specimens were collected from 132 Iranian native cattle and genomic DNA was extracted. PCR-RFLP method was used for amplification and determination of the leptin gene polymorphism. PCR was carried out between exon 2 (intron 2) and exon 3 (intron 3) and a 422 bp fragment was amplified. Two alleles (A and B), and three genotypes – AA, AB and BB – were observed in the studied population. The frequencies of A and B alleles were 77.27% and 22.73%, respectively. Furthermore, the frequencies of AA, AB, and BB genotypes were 59.09%, 36.36% and 4.55%, respectively. The results of this study showed that the AA genotype and the A allele were highly prevalent (P<0.01) in Iranian native cattle and that the homozygosity for AA genotype of leptin gene could be used as a genetic marker in Iranian native cattle.