An international team of scientists from the Max Planck Institute for Evolutionary Anthropology in Leipzig has sequenced ancient mitochondrial DNA from a finger bone found in southern Siberia. The bone is from a previously unknown form of human that lived in the Altai Mountains of Central Asia around 48,000 to 30,000 years ago. This mitochondrial genetic material, passed down through the descendants in the maternal line, is a sign of a new wave of migration out of Africa, one that is distinct from that of Homo erectus, the ancestors of Neanderthals and Homo sapiens. The discovery is reported in Nature, 24 March 2010.
Image credit: MPI für evolutionäre Anthropologie / Krause
Johannes Krause, Svante Pääbo and their colleagues from the Max Planck Institute for Evolutionary Anthropology in Leipzig have now sequenced mitochondrial DNA from a tiny fragment of a finger bone. The bone was found in the Denisova Cave in the Altai Mountains in southern Siberia in 2008. The scientists compared the ancient DNA from the mitochondria, the "powerhouses of the cell", with the mitochondrial DNA of Neanderthals and of humans alive today. They found that the mitochondrial DNA of this hominin from southern Siberia differed markedly from all other known hominins.
A detailed analysis of the mitochondrial genetic material showed that this hominin shared a descendant with modern humans and with Neanderthals about 1.0 million years ago. This common descendant is about twice as old as the shared descendant of anatomically modern humans and Neanderthals, as determined on the basis of their mitochondrial DNA. Furthermore, the age of the fossil indicates that this unknown form of human could have co-existed with Neanderthals and modern humans in southern Siberia.
Johannes Krause, Qiaomei Fu, Jeffrey M. Good, Bence Viola, Michael V. Shunkov, Anatoli P. Derevianko & Svante Pääbo, "The complete mitochondrial DNA genome of an unknown hominin from southern Siberia."
Nature, 24 March 2010, DOI: 10.1038/nature08976