Correlation Of Polymorphism Of Leptin Gene With Physical And Chemical Properties Of Muscles In Xinjiang Brown Cattle

In this test,145 cattle blood samples and 20 Xinjiang Brown cattle meat samples were collected in two Xinjiang Brown cattle breeding farm in Yili region.Using PCR-RFLP method,this trial studied single nucleotide polymorphisms(SNP) in two loci in Xinjiang Brown cattle Leptin gene exon2 E2JW and E2FB, and studied the shear force,inosine monophosphate content,fat content,hydroxyproline content,muscle fiber diameter and density of Xinjiang Brown cattle Semitendinosus,Longissimus dorsi,and a comparative analysis of small samples was made to find the influence of these two loci single nucleotide polymorphisms on Xinjiang brown beef quality traits.Results showed that:1.Polymorphic existed in the loci of Xinjiang Brown cattle Leptin gene exon2 E2JW and E2FB.2.Xinjiang Brown cattle Leptin gene exon2 E2JW loci might be lack of TT genotypes,but E2FB loci might be lack of CC genotypes.3.The allele A was the dominant allele for E2JW SNP,and the advantage was obvious,the allele T was the dominant allele for E2FB SNP,but the advantage was not obvious.4.For E2JW SNP,the genotype AA had more intermuscularfat yield than the genotype AT,and the difference was extremely significant(P＜0.01).5.For E2JW SNP,the shear force of AA genotype was higher than that of AT genotype,and it was significantly different(P＜0.01).6.For E2JW SNP,there was no significant effect(P＞0.05) on such traits as collagen content,inosine monophosphate content,muscle fiber diameter,muscle fiber density and so on..These results showed that SNP in loci E2JW had greater influence on intermuscularfat content and shear force,and had no significant impact on trait indicators of collagen content,inosine monophosphate content,muscle fiber diameter,muscle fiber density.