The CAST, CAPN1 And PRKAG3 Gene Polymorphism And Meat Quality Association Analysis Of Major Sheep Breeds In Gansu

In order to study the relationship between the PRKAG3,CAST and CAPN1 genes polymorphism and slaughter performance, meat quality of 5 sheep breeds(Gansu Alpine Merino, Small tail han sheep, Tibetan sheep, Mongolian sheep and Tan-sheep which were fed in a typical farming mode of Gansu province) in Gansu province at the molecular level and to explore the possibility of improving the slaughter performance and quality of sheep meat by using PRKAG3,CAST and CAPN1 as candidate genes, the polymorphism of genes were detected by PCR-SSCP in 5 sheep breeds, and the association between PRKAG3,CAST and CAPN1 gene polymorphism and slaughter performance, meat quality in aged 9 month were analyzed. The main research results are listed as follows:1.Two SNPs of PRKAG3 gene, A2689 G and A3659 G,were detected in five sheep breeds. The SNP A2689 G was located at intron 4.Based on the A2689 G, the highest heterozygosity was Tibet lamb, Gansu Alpine Merino took second place; The polymorphism information contents(PIC) values was 0.25 to 0.5, the moderate polymorphism. Addition to the Tibetan sheep sheep other four sheep breeds on this loci in a Hardy Weinberg equilibrium state by Chi-square test. The SNP A3659 G was located at exon 10. Based on the A3659 G,Tan-sheep had the hightest heterozygosity, addition to small tailed han sheep, PIC values was 0.25 to 0.5, the moderate polymorphism.Small tail han sheep had the lowest polymorphism.The SNP A2689 G of PRKAG3 had a significant influence on carcass weight and water loss rate(P<0.05,while SNP A3659 G had significant influence on pure meat percentage, the shear force(P<0.05).2.There were two SNPs in amplified fragments of CAST gene in the 5 sheep breeds.Based on the SNPs the PIC values was 0.25 to 0.5,the moderate polymorphism. The Ho value was all above 0.6, highly homozygous. Hadad weinberg balance test of 5 sheep breeds was deviating from the hardy weinberg equilibrium. Association analysis showed that mutation loci has significant influence on the filtration rate and shear stress(P<0.05).3. One SNP of CAPN1 gene, A630 G, was detected in 5 sheep breeds. Based on this SNP the PIC value of 5 sheep breeds was 0.25 to 0.5, moderate polymorphism. Association analysis showed that the SNP had significant influence on carcass weight and fleshcolor(P<0.05).4. The combining effect of all these genes showed that AB- FF- AB- BB genotype was beneficial to improve the water loss rate and fleshcolor(P<0.05),the AA- FF-AB- BB genotype were highly significant to enhence carcass weight and fleshcolor(P<0.05).