Abstract: Lipoprotein lipase (LPL) is a 54 kb glycoprotein, and its activity is affected by nutritional factors and hormone levels ect conciliation. Because the particularity of the yak living environment intended Tianjun yak the LPL-Exon7 gene polymorphism at the molecular level, and with the growth and development traits associated analysis for the yak nutritional regulation of species resources protection, genetic breeding scientific theory basis. Qinghai Haixi Tianjun yak anticoagulant 106 extracted blood samples were taken DNA, and polymorphism analysis of candidate genes LPL-Exon7 adopted the use of PCR technology and high-resolution melting curve analysis, and measured yak weight, body length, body height, bust, tube Wai growth traits and genetic effects. The results showed that the polymorphic yak and wild blood yak of the LPL-Exon7 gene were polymorphism, there were three genotypes, named AA, AB, BB, controlled by a pair of alleles A and B, A allele was the dominant allele. Loci balanced detection χ² test, in line with the law of Hardy-Weinberg, a state of equilibrium (P>0.05). The female and male of domestic yak and wild blood yak polymorphic information were 0.3588 and 0.2103, 0.3219 and 0.3343, polymorphic information content of domestic yak cows was PIC<0.25, at the low degree of polymorphism, the polymorphic information content of domestic yak bull wild blood yak public was in the 0.25<PIC<0.50, was a moderate polymorphism. LPL-Exon7 site polymorphism to yak weight,height and pipe circumference the existence of a significant effect (P<0.05).Yak body slanting length and heart girt were no significant effect (P>0.05). Therefore, the LPL-Exon7 was considered as one of yak genetic markers for marker-assisted selection.

Key words: Bos grunniens; lipoprotein lipase-Exon7; PCR; high-resolution melting curve analysis; polymorphism; correlation