Autosomal STR variation in five Austronesian Populations

Human population characteristics at the genetic level are integral to both forensic biology and population genetics. This study evaluates biparental microsatellite markers in five Austronesian-speaking groups to characterize their intra- and interpopulation differences. Genetic diversity was analyzed using 15 short tandem repeat (STR) loci from 338 unrelated individuals from 5 Pacific islands populations, including the aboriginal Ami and Atayal groups from Taiwan, Bali and Java in Indonesia, and the Polynesian islands of Samoa. Allele frequencies from the STR profiles were determined and compared to other geographically targeted worldwide populations procured from recent literature. Hierarchical AMOVA analysis revealed a large number of loci that exhibit significant correspondence to linguistic partitioning among groups of populations. A pronounced divide exists between Samoa and the East (Formosa) and Southeast Asian (Bali and Java) islands. This is clearly illustrated in the topology of the neighbor-joining tree. Phylogenetic analyses also indicate clear distinctions between the Ami and Atayal and between Java and Bali, which belie the respective geographic proximities of the populations in each set. This differentiation is supported by the higher interpopulation variance components of the Austronesian populations compared to other Asian non-Austronesian groups. Our phylogenetic data indicate that, despite their linguistic commonalities, these five groups are genetically distinct. This degree of genetic differentiation justifies the creation of population-specific databases for human identification.