Molecular population genetic studies of the island peoples of the South Pacific.

The introduction of molecular genetic techniques to survey DNA variation directly has greatly advanced the study of inter- and intra-population variability. One of the first DNA polymorphisms to be surveyed for population variation was the α-globin copy number variants in Melanesia, and this study indicated a new role for malarial selection. Subsequently, DNA sequence polymorphism was investigated by the definition of haplotypes, which result from linkage disequilibrium among site polymorphisms. Distributions of α-globin haplotypes clearly demonstrate the effects of migration on population affinities in Melanesia and Polynesia. Analysis of neutral diversity in the nuclear genome has been enriched by the discovery of variable numbers of tandem repeats (VNTRs), particularly the hypervariable mini-satellites. Highly allelic VNTRs are sensitive to the effects of genetic drift caused by bottlenecks or population subdivision, and in Oceania they reflect the demography of colonization. Because VNTRs are subject to high and variable rates of mutation, they are informative within a range of recent evolutionary time scales and, together with other DNA polymorphisms, contribute to a more complete interpretation of a population's history. © 1996 Wiley-Liss, Inc.