MELBOURNE, AUSTRALIA—According to a Science Magazine report, a comparison of Neanderthal genomes, the genomes of 56 living people from Papua New Guinea, and the genomes of Denisovans recovered from Siberia’s Denisova Cave suggests that modern Papuans inherited more than 80,000 Denisovan gene variants. Some of those genes are thought to have fine-tuned the immune systems of modern Papuans to the environment. In particular, several of the variants were shown to reduce the inflammatory response in white blood cells collected from Papuans by Christopher Kinipi of the University of Papua New Guinea. “In the tropics where people have high loads of infectious disease, you might want to tone down the immune response a little and not go overboard,” explained evolutionary geneticist Irene Gallego Romero of the University of Melbourne. Such gene swaps with other hominins, who were well adapted to the regions in which they lived, would have allowed migrating modern humans to adapt quickly to new areas with new pathogens, concluded computational biologist Janet Kelso of the Max Planck Institute for Evolutionary Anthropology. Read the original scholarly article about this research in PLOS Genetics. For more on Denisovan DNA, go to "Our Tangled Ancestry."