Genetic Ancestry of South America's Indigenous Mapuche Traced

Researchers have traced the genetic ancestry of the Mapuche, an Indigenous group from a region of South America that spans present-day Argentina, Uruguay, and most of Chile. As they report in Current Biology, the University of Zurich-led team generated and analyzed genome-wide data from 64 individuals belonging to three different Mapuche populations in southern Chile, comparing what they found to published Native American data and data from ancient DNA samples. They report that Mapuche ancestry belongs to a genetic cluster characteristic of southern South America that is equally distance from Central Andres and Amazonia clusters and dated the split between these clusters to the early Holocene. Though there was a deep genetic split between the Central and Southern Andes populations, the researchers note later instances of gene flow, likely arriving alongside new crops and loanwords. The three different Mapuche populations analyzed, meanwhile, are closely related, with one group, the Huillich, experiencing recent exchanges with groups from the southernmost reaches of the continent. "Our findings add new perspectives on the genetic (pre)history of South America, from the first settlement through to the present-day Indigenous presence," the researchers write. "Follow-up fieldwork took these results back to the Indigenous communities to contextualize the genetic narrative alongside Indigenous knowledge and perspectives."