| MyoD gene family includes MyoG, MyoD, MRF4 and MyfS. This gene family controls the whole muscle development process: from pre-muscle cell's typing, propagation and conform of muscle fiber to the maturation and the function-completing of postnatal individual. So MyoD gene family is very important to the vertebrate in differentiation of muscle cell and developmental maturation of skeletal system, and that the analysis of MyoD gene family has theoretical and practical significance in swine breeding.The study object includes Minzhu, Sanjiangbaizhu, Dabaizhu, Changbaizhu, Junmuyihao, Duluoke and Shuangjitundabaizhu. According to the sequences of MyoG, MyoD and Myf5 of swine in GenBank, seventeen pairs of primers for MyoG, MyoD and Myf5 were designed. PCR-SSCP technology was applied to detect SNPs of the exons of the three genes. Detected results of genotype demonstrate that no polymorphism in MyoG and MyoD, and some SNPs in three exons of MyfS. One mutant site in the first exon of Myf5: G C; three mutant sites in the second exon of Myf5 : C A, A G, G A; in the third exon of Myf5, one base A deficiency at 3387bp, three bases T deficiency at 3417bp, one mutant site at 3443bp: T C.The computation of genotype frequency, gene frequency and statistical analysis demonstrate that as lean meat frequency of Minzhu, Sanjiangbaizhu, Dabaizhu, Changbaizhu, Junmuyihao, Duluoke and Shuangjitundabaizhu raise, the gene frequency of allelic gene M is also raise as this trend haply.Combining this study result with lean meat frequency and selective breeding condition, we obtain a tendentious conclusion that gene frequency of allelic gene M of MyfS one hand is positively correlated with lean meat frequency, on the other hand is correlated with the orientation of selective breeding. We conclude that allelic gene F is possibly correlated with high lean meat frequency. Through statistical analysis, allelic gene A, B, C of Myf5 have no obvious correlation with lean meat frequency of different swine breeds. In addition, the high polymorphism of Myf5 demostrates that seven swine breeds are rich in information of genetic variation, and have high selective competency.Postgraduate: Li JingfenSpeciality: Animal genetics and breedingAdvisor: Professor Liu Di... |
