[Genetic diversity of seven miniature pig breeds (strains) analyzed by using microsatellite markers]

Twenty-seven microsatellite markers recommended by the Food and Agriculture Organization (FAO) and the International Society for Animal Genetics (ISAG) were used to analyze the genetic diversities of 7 Chinese native miniature pig breeds/strains (Jiuyang Xiang Pig, Jianbai Xiang Pig, Congjiang Xiang Pig, Huanjiang Xiang Pig, Black Xiang Pig, Wuzhishan Pig, and Diannan Small Ear Pig) and 3 western pig breeds (Duroc, Large White, and Landrace). The results indicate that there exists, in general, a high degree of genetic variability within the 7 miniature pig breeds. However, the genetic variability in Jiuyang Xiang Pig, Jianbai Xiang Pig, Huanjiang Xiang Pig, and Congjiang Xiang Pig (average PICs being 0.61-0.64) was significantly lower than that in the other three miniature pig breeds (average PICs being 0.60-0.84). The genetic divergence among Jiuyang, Jianbai, Huanjiang, and Congjiang was very small (Nei's standard genetic distances being 0.12-0.22), but it was large between them and the other three miniature pig breeds (Nei's standard genetic distances being 1.61-1.96), and even larger between them and the three foreign breeds (Nei's standard genetic distances being 1.99-3.30). Cluster analysis reveals three obvious clusters for the 10 breeds: Jiuyang, Jianbai, Huanjiang, and Congjiang are in one cluster, the other three miniature pig breeds in the other, and the three foreign breeds in the third. These results are consistent with the geography distribution and origin of these breeds.