Origin and evolution of two Yugur sub-clans in Northwest China: a case study in paternal genetic landscape.

摘要

BACKGROUND: Yugur is an ethnic group that was officially identified by the Chinese Government in 1953. Within the population there are two sub-clans distinctly identified as the Eastern Yugur and Western Yugur, partly because they have different local languages. AIM: A parentage comparison was conducted between the two sub-clans to investigate their genetic relationship. SUBJECTS AND METHODS: Male subjects were chosen from the two clans to investigate their paternal genetic landscape through typing 14 single nucleotide polymorphisms (SNP) and 12 short tandem repeats (STR) of the Y chromosome. RESULTS: Significant differences were revealed between the sub-clans at the haplogroup level. Genetic divergence was also observed by analyses of multidimensional scaling (MDS) and principal components (PC). Genetically, the Eastern Yugur are closer to the Han Chinese and Mongolian people than the Western Yugur. The Uygur people, who share a common ancestor (ancient Huihu) with the Yugur, were genetically separatefrom both sub-clans of Yugur. Moreover, the constructed phylogenetic network for haplogroup O provided further evidence that the two Yugur sub-groups present an underlying genetic difference. CONCLUSION: Overall, the diffusion of Mongolians during the Mongol Period has affected the Eastern Yugur more than the Western Yugur. The genetic contribution of the Han people to the Eastern Yugur seems to be more pronounced than to the Western Yugur. Besides the two different contributions referred to above, small population size and genetic drift have resulted in the genetic differentiation of the current sub-clans of Yugur.