Genome Analysis Estimates Size of Samoa’s Early Population

PROVIDENCE, RHODE ISLAND—According to a UPI report, a team of researchers including Stephen McGarvey of Brown University analyzed the genomes of some 1,200 people living on the Pacific island of Samoa in an effort to reconstruct the island's population history. They found that there were between 700 and 3,400 individuals living on the island from about 3,000 to 1,000 years ago, when the population grew to about 10,000 individuals. The population then declined after the arrival of Europeans in the eighteenth century, and only began to increase again around 150 years ago. The study also indicates that modern Samoans are descended from the aboriginal peoples of Taiwan, the islands of Southeast Asia, coastal New Guinea, and other Oceanic islands. McGarvey and his colleagues think the small size of Samoa’s founding population, when combined with the process of natural selection in the new environment, may have increased the frequency of genes in today’s population that are associated with risk factors for cardiac and metabolic diseases. For more on the peopling of Pacific islands, go to "Letter from Hawaii: Inside Kauai's Past."