MtDNA Analysis of Bunun Remains Stored in the National Taiwan University

Abstract

The Bunun tribe is one of the aboriginal Taiwanese populations living in the central mountain area of Taiwan. In this study, we analyzed the sequence variability of hypervariable region I and II of mitochondrial DNA (mtDNA) in order to investigate the relationships between modern and historical Bunun populations. mtDNA sequences were retrieved from 25 of 34 samples that were obtained from the historical Bunun skeletal remains stored in National Taiwan University. In combination with the mtDNA data of 8 extant Taiwan aboriginal populations, we carried out phylogenetic analysis based on haplogroup frequency data. The results show that the genetic structure of the historical Bunun population is a complex matriline and that these samples share the same haplogroup with the extant Bunun population. Analysis of the genetic composition of the aboriginal populations also reveals an important ethnic heterogeneity of the present aboriginal Taiwanese. Analysis of genetic distances based on haplogroup frequencies revealed 2 distinct clusters composed of northern and central mountain groups (Atayal, Saistat, and Bunun) and east coast and southern mountain groups (Paiwan, Rukai, Amis, and Yami). The mtDNA haplogroups in the Taiwan aboriginal populations were found to be different from those in the Chinese and Taiwan-Han population; therefore, these Taiwan aboriginal haplogroups might have stemmed from the gene pool of the initial late Pleistocene settlers. Genetic diversity among the aboriginal populations may be attributed to the prolonged isolation and random genetic drift after the single introduction of all mtDNA haplogroups into Taiwan. Our experiments also indicate the availability of the past skeletal remains for verifying the hypotheses formulated on the basis of genetic data derived from the present populations.