Genetic structure and subspecies divergence of wild boars Sus scrofa in mainland China based on the microsatellite variation analysis

In order to discuss the subspecies classification of wild boar Sus scrofa in China, We studied their genetic structure using 11 microsatellites, with emphasis on South China. High levels of genetic variationwere detected in South China (SC), North China (NC) and Northeast China (NE) wild boar populations. This was consistent with the huge population size of the wild boar and its status as a widely-distributed species. Weak genetic divergence was observed in all subspecies involved in this study. Individuals from all subspecies were highly mixed in the phylogeny tree based on the allele sharing distance (DAS), no distinct clade was found according to the defined subspecies. Even considering the two main factors, which reflect the biggest genetic differentiation among the populations, it is impossible to distinguish SC,NC and NE from each other by FCA (Factor Correspondence Analysis). Using the F-statistic test, weak genetic differentiation (Fst = 0.014) was detected between SC and NC population, which indicated a high gene flow between two sides of the Yangtze River. The Yangtze River is an insurmountable geographical hindrance for wild boars. The stronger population differentiations were observed between NE and NC population, and between NE and SC population（Fst = 0.040, 0.042 respectively）, this may suggest that the wild boars in NE area could be defined as the subspecies S. s. ussuricus.[Acta Zoologica Sinica 54(5): 753 – 761, 2008].