The colonization of the Pacific: the story according to human leukocyte antigens.

The human leukocyte antigen (HLA) distributions in 16 Pacific populations have been collated from published and unpublished reports. Gene frequency and linkage disequilibrium relationships among groups show that Australians and Papuans share a common ancestry, that coastal Melanesia has about 16% Austronesian admixture, and that Fiji is truly intermediate between Melanesia and Polynesia. In Polynesia, Cook Islanders show closer affinity with populations of Western Polynesia than with Maoris and Easter Islanders, in contrast to their linguistic affiliations, but otherwise HLA distributions show a clear division between the populations of Eastern and Western Polynesia. This study emphasizes the contribution the HLA system can make to anthropological studies and has provided a version of colonization of the Pacific compatible with theories based on prodigious efforts in many disciplines.