1Department of Biological Statistics and Computational Biology, Cornell University, 2Department of Anthropology, University of Wisconsin-Madison
Friday 4:45-5:00, 200ABC
The contribution of Neandertal populations to present-day peoples illuminates the process of recent human evolution. The Neandertals were a relatively peripheral population that occupied western Eurasia from roughly 150,000 to 30,000 years ago. Nuclear genomic evidence has been recovered from several later Neandertals, after 50,000 years ago (Green et al. 2010). Neandertal genomes are more similar to living people who trace most of their recent ancestry to regions outside Africa. By contrast, sub-Saharan African people today have less Neandertal genetic similarity. These comparisons show that in addition to deriving more than 90% of their genetic heritage from ancient Africans, most present-day people outside Africa derive a fraction of their ancestry from the Neandertals (Green et al. 2010).
These comparisons leave unanswered questions. Was population mixture with Neandertals limited to non-African populations, or do today's Africans also have some Neandertal ancestors? Did mixture occur as a singular event, or was there a long process of population interaction? Did populations who succeeded the Neandertals in Europe have a higher fraction of Neandertal ancestry?
We carried out a series of comparisons to address these questions. By examining the Neandertal similarity of individuals from the 1000 Genomes Project, we have substantially expanded the sample of Neandertal-human comparisons. We also examined the genome of the Tyrolean Iceman, a European from approximately 5300 years ago. This is the first comparison of Neandertal genomes to the genome of a prehistoric modern human individual.