Denisovan DNA still influences Oceanian immunity, but researchers remain unsure why

A large, first-of-its-kind map of Denisovan-derived DNA in Oceanian populations identified about 3,127 variants that still influence immune-system genes today; many are unique to Oceania, and natural selection increased their frequency in Near Oceania, suggesting Denisovan DNA helped defend against novel pathogens, though the exact benefits vary and researchers say more Oceanian genome sequencing is needed to fully understand health implications.