The Study Of Genetic Heterogeneity In Hakka Population By MtDNA Lineages

Objective：To further recognize the genetic structure of Hakka population and to explore thegenetic variation in Hakka, the matrilineal genetic structure of Hakka population from variousareas were compared for analyzing. Moreover, this study can also contributes to trace the originand evolutionary history of Hakka.Methods：A total of180blood samples were collected from two Hakka populations inhabiting inGuangdong Province with appropriate informed consent, including125Hakka residing in Dabucounty of Meizhou and55individuals from Heyuan region. With the aid of information choosenfrom the hypervariable segments I and II as well as some necessary coding-region segments, allmtDNAs were assigned into respective (sub-) haplogroup.Results：The comparison of haplogroup distribution frequencies among these groups revealed anobvious geographic difference in Hakka. For Heyuan, southern prevalent haplogroups B, M7, R9account for52.7%of total mtDNA lineage, whereas, in Meizhou and Changting Hakka, itpresent at comparatively high proportions, ranging from57.4%to61.9%. Further, Heyuansamples showed by far the highest frequencies of A (5.5%), D (20.0%), G (5.5%). Even thoughtwo Meizhou samples from the same geographic location, the evident differences in frequenciesof F, M8a and Z were still observed. In the PC map, all four Hakka groups take intermediateposition of the chart, and Heyuan is much closer to Miao and northern Han such as Henan thanother three Hakka groups, whereas Meizhou and Changting are more tend to cluster with Yaoand some populations of Bai-Yue tribe ancestry, such as Dai and MulamConclusion：The differences of genetic components between different regional Hakka groupsindicate the genetic complexity of Hakka, and suggest that Hakka could be a heterogeneouspopulation, more or less, at matrilineal lineage level. With the strictly quality-control measuresunder the guideline of phylogenetic knowledge, the data could well supplement the ChinesemtDNA database as well as will be useful for further investigation of the genetic structure ofEast Asian.