The Fujian Tanka people are officially classified as a southern Han ethnic group while they have customs similar to Daic and Austronesion people. Whether they originated in Han or Daic people, there is no consensus. Three hypotheses have been proposed to explain the origin of this group: 1) the Han Chinese origin, 2) the ancient Daic origin, 3) and the admixture between Daic and Han. In this study, we address this issue by analyzing the paternal Y chromosome and maternal mtDNA variation of 62 Fujian Tanka and 25 neighboring Han in Fujian. We found that the southern East Asian predominant haplogroups, e.g. O1a1a-P203 and O1b1a1a-M95 of Y chromosome and F2a, M7c1, and F1a1 of mtDNA, reach relatively high frequencies in Tanka. The interpopulation comparison reveals that the Tanka have a closer affinity with Daic populations than with Han Chinese in paternal lineages while are closely clustered with southern Han populations such as Hakka and Chaoshanese in maternal lineages. Network and haplotype-sharing analyses also support the admixture hypothesis. The Fujian Tanka mainly originate from the ancient indigenous Daic people and have only limited gene flows from Han Chinese populations. Notably, the divergence time inferred by the Tanka-specific haplotypes indicates that the formation of Fujian Tanka was a least 1033.8-1050.6 years before present (the early Northern Song Dynasty), indicating that they are indigenous population, not late Daic migrants from southwestern China
