Genetic Diversity Analysis With Microsatellite DNA On Sichuan-Tibetan Pig And Its Variation Between Generations

In this thesis, PCR-PAGE method was used in this study to analysis the genetic diversity of three groups among Sichuan-Tibetan pigs at eighteen microsatellite locus.We explored the genetic relationship between groups and genetic variation within the groups; and analyzed the genetic variation of Aba population. The results as following:We detected 108 alleles at 18 microsatellites locus in the three groups of Sichuan-Tibetan pigs, an average of 6.0000 per locus alleles. Specifically,61 alleles were found in 108 Aba pigs, an average of 3.3889,70 alleles were found in 18 Daocheng pigs, an average of 3.8889, and 72 alleles were found in 17 Dege pigs, an average of 4.0000.The average effective number of alleles is among 1.4980-3.4791 at 18 microsatellites locus in the three groups.The average effective number of alleles in Aba, Daocheng and Dege groups are 2.1301,2.6957 and 2.5014 respectively.The average polymorphism information content is between 0.2774-0.6535 at 18 microsatellites locus in the three groups. SW2442,S0227,IGF1,SW1202,S0101,SW268,SW951,SW66,S0004,S0026,SW24 locus were moderate polymorphic and ALPHA,SW1443,SW911,SW957,SW2459,SW886,SW787 locus were highly polymorphic. Analysis from the three groups, the average polymorphism information content between 0.4071-0.5306, Aba group showed moderate polymorphism, Daocheng and Dege groups showed a high degree of polymorphism.By heterozygosity, F statistics and genetic distance analysis, the heterozygosity of three groups at 18 microsatellite locus are diffent.The average heterozygosity is between 0.0216(IGF1)-0.6353(SW2459), The average heterozygosity of Aba, Daocheng, Dege were 0.2130,0.3272 and 0.3562. The genetic variation between groups was 21.54%, the genetic distances between them Were more than 0.6, and the average gene flow is greater than 1. Suggest that the three groups have different features, frequent gene flow within groups and low heterozygosity.Aba groups at the microsatellite locus intergenerational diversity analysis showed that the microsatellite locus polymorphic information content remained relatively stable, with the generation of increased heterozygosity down from generation to generation, the group is becoming homozygous.