Studies On Effects Of AMPD1 And MYF6 Genes Polymorphisms On Partial Economic Traits In Pigs

By adopting Polymerase Chain Reaction-Restrain Fragment Length Polymorphism(PCR-RFCP),the genetic variations of AMPD1 and MYF6 gene were detected in 923 pigs including 10 groups:Duroc,Yorkshire,Landrace,Hybrid breeds: DL Y(Duroc×Landrace×Yorkshire),LY(Landrace×Yorkshire),Ningxiang,Daweizi, Taoyuan,Shaziling,Wuzhishan.Then the genotype frequencies and gene frequencies were calculated according to the PCR-RFLP.The differences of genotype frequencies between groups were analyzed by Chi Square Test.At the same time,the effects on meat-quality traits and carcass traits of AMPD1 gene which was the first studied on pigs in China and MYF6 gene were estimated according to their slaughter datu.The main results are showed as follows:1.The genetic polymorphism and effect of AMPD1gene.1.1 There were great polymorphisms in RsaⅠrestriction loci of AMPD1 gene in Ningxiang,Daweizi,Shaziling,Taoyuan,Wuzhishan,three types of exotic-breeds. DLY and LY breeds;genotype AA,AC,CC were found in the native breeds Ningxiang,Daweizi.Shaziling,Taoyuan and Wuzhishan;genotype CC could be found in none of the exotic breeds:Duroc,Landrace and Yorkshire;Allele A was the superiority allele in the hybrid breeds;1.2 The traits of hind leg proportion were different in these five breeds:Duroc, Yorkshire,Landrace,DLY and LY.The individuals with AC genotype were taller by 22.76%,16.80%,17.90%,21.95%,and20.69%respectively than individuals with AA genotype's.If the AC genotype selected,the hind leg proportion would be enhanced. As to the traits of average fat thickness,the Yorkshire and Landrace individuals with AC genotype were lower than individuals with AA genotype by30%and26.36%,and If the AC genotype selected,the average fat thickness would be reduced and the lean percentage would be increased distinctly.On the two breeds of Duroc and Landrace,Selecting the AC genotype could reduce average skin thickness and fat percentage efficiently.1.3 Concerning the water loss traits of these five breeds:Duroc.Yorkshire, Landrace,DLYand LY,the individuals with AC genotype were lower than the ones with AA genotype by 1.50%,6.68%,35.91%,1.25%and 30.92%respectively,and Selecting the AC genotype could reduce the water loss.The AC genotype had significant higher in the drip loss than the AA 's.2.The genetic polymorphism and effects of MYF6 gene2.1 In the three types of exotic breeds and DLY,LY,there were great polymorphisms in MspⅠrestriction loci of MYF6 gene,whereas there were little or no polymorphisms in native breeds;in local breeds,there were no CC genotype and Allele T was the superiority allele;in the exotic breeds,Allele C was the superiority allele,and the highest frequency was Yorkshire,the lowest was Duroc;Allele C was the superiority allele in DLY and LY;2.2 With regard to trait of fat percentage,the individuals with CC genotype were lower than the ones with TT genotype by 97.06%,15.2%,10.67%,22.91%and 19.16% respectively.Selecting the CC genotype could reduce the fat percentage obviously.On the two breeds,Yorkshire and LY,individuals with CC genotype had lower average measured back fat thickness by 38.92%and 36.85%respectively than that of the ones with TT genotype.Individuals with CC genotype had thinner back fat thickness and higher lean percentage,and allele C took on certain positive effect.2.3 On the water loss trait of Yorkshire breed,Allele C operated negatively in increasing the Water loss percentage;while on the water loss trait of Landrace, Allele C operated positively in decreasing the water loss percentage.But the results were not so distinct on other breeds.On the trait of Drip loss,Allele C operated negatively in increasing Drip loss.The studies indicates that AMPD1 and MYF6 genes could be used as candidate genes or molecular marker related to the back fat thickness,lean percentage,partial carcass traits,water loss and drip loss traits.