Two studies drawing on whole genomes from more than 1,000 French Polynesian participants show Polynesian founder effects at least ten times stronger than Finland's, concentrating disease-causing and protective variants that global databases miss.
Polynesians carry founder effects at least ten times stronger than those of Finland, long the textbook example of a founder population, according to two studies highlighted on Monday that draw on whole genomes from more than 1,000 people in French Polynesia. The work shows how repeated island settlement concentrated both disease-causing and protective gene variants that the world's largest genetic databases largely miss.
The first paper, titled Message in a bottleneck and published in Science, was led by researchers at Stanford University and the University of California, San Diego, with Variant Bio as a co-author, and was featured on the journal's cover. It draws on the Ma'i 'u'u study in French Polynesia, newly sequenced genomes from Rapa Nui and Native Hawaiian data from the National Institutes of Health All of Us programme. As Polynesians settled island after island, each voyage carried only a small founding group, and each successive settlement carried a smaller subset of the gene pool that came before it.
The genomes also rewrite a piece of Pacific history. Hawaii and Rapa Nui, about 7,000 kilometres apart, turn out to be the most closely related of the remote island populations studied, suggesting both were settled by voyagers whose deeper roots trace back to Mangareva. The researchers describe the pattern as nested founder effects, like a set of Russian dolls, and argue it supports a tradition of repeated long-distance voyaging across the Pacific.
The second paper, in Nature Communications, shows what those bottlenecks make possible for medicine. Gene-disrupting variants that are nearly absent worldwide are common enough in Polynesia to reveal their effects on health, including a promising drug-target lead, and variants linked to conditions such as dislocated lens, progressive vision loss and kidney failure are carried by 2 to 3 percent of the Eastern Polynesians studied, a level that meets standard thresholds for genetic screening recommendations.
The announcement from Variant Bio, which sponsored the Ma'i 'u'u study with clinicians, community leaders and academic partners across the Pacific, confirms the two papers, their journals and the size of the study, and independent coverage of the Science paper matches its title, its Mangareva finding and its account of nested bottlenecks. The papers were published earlier this month rather than on Monday itself, so the news is the joint announcement of the pair and their combined medical message, not a single new publication.
The practical consequence is a gap in care. Native Hawaiians number nearly twice the Amish population yet still lack genetic testing guidelines for conditions that screening could catch, and the researchers argue that Polynesian populations deserve research resources and attention from geneticists at least as urgently as the founder populations genetics already studies.