Influence of leptin gene polymorphism on back fat thickness in Simmental cross breed cattle (Bos Taurus)

Abstract

Leptin is the hormone product of the obese gene and is involved in regulation of appetite, body composition and meat quality in mammals. Polymorphisms in the leptin gene in cattle have been associated with serum leptin concentration, feed intake, milk yield and body fatness. The objective of this study was to detect polymorphisms in the obese gene of Chinese Simmental bulls, that are associated with variation in back fat thickness and body weight. PCR products of the leptin gene from 51 individual animals were sequenced and compared to the NCBI Bos Taurus leptin genotype. Back fat thickness was measured using ultrasound. In the population studied, 5 SNPs were detected. There was a C-T substitution at location 14697 of leptin gene exon 2, resulting in a amino acid change of an arginine to a cysteine (E2-R25C) In the 3' untranslated region of the gene, the following SNP’s were found: A-G substitution at location 18095, C-T substitution at location 18268, T-C substitution at 19130 and a G-T substitution at 19263. The results showed no association between the genotypes and traits studied. Conflicting findings have been reported by other authors, and our results confirm those which did not find any association between leptin polymorphism and back fat thickness in Bos taurus Simmental bulls. However, results might be inadequate because of a limited animal population studied.