R159Q Polymorphism in Leptin Gene and Its Correlation with Semen Quality Parameters in Nili-Ravi Buffalo Bulls

摘要

Genome analysis in animals has introduced new criteria for selection and development of strategies for increasing herd productive and reproductive potential through breeding. Leptin gene has been established as a potential candidate for marker assisted selection of animals This study was aimed to find polymorphism in leptin gene and its relationship with male reproductive traits and semen quality parameters in 99 Nili-Ravi buffalo breeding bulls. DNA was extracted from whole blood for genome analysis of each experimental bull. PCR product was sequenced and data was analyzed for polymorphism. Results revealed the presence of R159Q polymorphism at position c.523. This polymorphism was heterozygous and the change of guanine to adenine (GA) nucleotide was noted in experimental bulls. Sequence comparison of leptin gene revealed two genotypes, GG and GA, with frequencies of 68.69 and 31.31%, respectively. The allelic frequencies for A and G allele were 15.66 and 84.34%, respectively. Codon CGG was changed into CAG, which resulted in glutamine production instead of arginine (RQ). Further analysis of data showed that the R159Q polymorphism was significantly negatively correlated with sperm motility after freezing. However, it had non-significant correlation with ejaculatory volume, mass activity, sperm concentration, individual sperm motility, sperm motility after dilution, live and dead sperm percentage. Findings of present study suggest that R159Q polymorphism of leptin gene might be considered as genetic marker for selection of buffalo bulls. Further study is needed to explore the mutations in other regions of this gene which may affect semen quality parameters in males of this specie. (C) 2018 PVJ. All rights reserved