[Genetic relationship among four Yunnan populations revealed by sequence of mtDNA D-loop]

mtDNA D-loop noncoding region 16048-16569 and the following 1-41 (563 bp) in 99 individuals of four Yunnan ethnic minorities (Dai, Wa, Lahu and Tibetan) were sequenced and then a phylogenetic tree was reconstructed by Neighbor-Joining method. These 99 mtDNA lineages were classified into 3 genotype groups in the tree. All lineages with 9 bp deletion in the COII/tRAN(Lys) intergenic region were clustered in group I, some individuals of Dai, Lahu, Wa and only 2 Tibetan individuals clustered in group II, individuals of all four populations were included in group III. A phylogenetic tree of the four populations was constructed by NJ method on the basis of estimate of net genetic distance among them. Our results showed, the genetic distance among Dai, Wa and Lahu is very close, but far from Tibetan, their genetic distance is similar to their geographic distance. Although both as descendants of ancient Di-Qiang tribe in history and speaking similar language, Lahu and Tibetan are not closely related. This result indicates that there are different origins of these two populations.