Recent technological advances have made it possible retrieve and sequence DNA from ancient bones and other tissue remains found at archaeological excavations. Over the past decade we have reconstructed the genomes of several Neandertals, and also retrieved the genome of a previously unknown extinct Asian hominin group related to Neandertals, which we call “Denisovans”. These genome sequences offer a unique opportunity to explore the population histories of modern humans and of our extinct Neandertal and Denisovan relatives, and to learn about our similarities and differences. We have learned that the ancestors of some of us interbred with both Neandertals and Denisovans such that all present-day people outside of Africa carry approximately 2% Neandertal DNA, and that some populations, largely in Oceania, also carry DNA from Denisovans. This introgressed DNA has been shown to have both positive and negative outcomes for present-day carriers: underlying apparently adaptive phenotypes such as high altitude adaptation, as well as influencing immunity and disease risk. In recent work we have identified Neandertal haplotypes that are likely of archaic origin and determined the likely functional consequences of these haplotypes using public genome, gene expression, and phenotype datasets. The archaic genomes have also allowed us to identify the genetic changes that are unique to modern humans and not shared with Neandertals or Denisovans, and ongoing work aims to determine whether any of these genetic variants might underlie traits characteristic of modern humans.
More about the speaker
Janet Kelso is a South African born computational biologist and group leader of the Minerva research group for Bioinformatics at the Max Planck Institute for Evolutionary Anthropology. She obtained her BSc-degree in biology from the former University of Natal (now UKZN) in 1995, followed by a BScHons-degree in medical biochemistry and an MSc in chemical pathology from the University of Cape Town in 1997 and 2000. In 2003 she obtained her PhD in bioinformatics from the University of the Western Cape under the guidance of Professor Winston Hide. She joined the Max Planck Institute in 2004. She is the recipient of numerous awards and fellowships, including inter alia the AAAS Newcomb Cleveland Prize for the most outstanding paper in Science in 2010, and in 2016 she was elected Fellow of the International Society for Computational Biology (ISCB).
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