The international research team, which includes researchers from the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health, reports its findings in the May 7, 2010, issue of Science.
The current fossil record suggests that Neanderthals, or Homo neanderthalensis, diverged from the primate line that led to present-day humans, or Homo sapiens, some 400,000 years ago in Africa. Neanderthals migrated north into Eurasia, where they became a geographically isolated group that evolved independently from the line that became modern humans in Africa. They lived in Europe and western Asia, as far east as southern Siberia and as far south as the Middle East.
Approximately 30,000 years ago, Neanderthals disappeared. That makes them the most recent, extinct relative of modern humans, as both Neanderthals and humans share a common ancestor from about 800,000 years ago. Chimpanzees diverged from the same primate line some 5 million to 7 million years ago.
The researchers compared DNA samples from the bones of three female Neanderthals who lived some 40,000 years ago in Europe to samples from five present-day humans from China, France, Papua New Guinea, southern Africa and western Africa. This provided the first genome-wide look at the similarities and differences of the closest evolutionary relative to humans, and maybe even identifying, for the first time, genetic variations that gave rise to modern humans.
"This sequencing project is a technological tour de force," said NHGRI Director Eric D. Green, M.D., Ph.D. "You must appreciate that this international team has produced a draft sequence of a genome that existed 400 centuries ago. Their analysis shows the power of comparative genomics and brings new insights to our understanding of human evolution."
The Neanderthal DNA was removed from bones discovered at Vindija Cave in Croatia and prepared in the clean room facility of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, to prevent contamination with contemporary DNA. The Max Planck group is led by their Department of Evolutionary Genetics Director Svante Pääbo, Ph.D., a well-known pioneer in Neanderthal genome research. The team deposited the Neanderthal genome sequence in the publicly available NIH genetic sequence database GenBank.
To understand the genomic differences between present-day humans and Neanderthals, the researchers compared subtle differences in the Neanderthal genome to the genomes found in DNA from the five people, as well as to chimpanzee DNA. An analysis of the genetic variation showed that Neanderthal DNA is 99.7 percent identical to present-day human DNA, and 98.8 percent identical to chimpanzee DNA. Present-day human DNA is also 98.8 percent identical to chimpanzee.
"The genomic calculations showed good correlation with the fossil record," said coauthor Jim Mullikin, Ph.D., an NHGRI computational geneticist and acting director of the NIH Intramural Sequencing Center. "According to our results, the ancestors of Neanderthals and modern humans went their separate ways about 400,000 years ago."
The comparison between Neanderthal and present-day human genomes has produced a catalog of genetic differences that allow the researchers to identify features that are unique to present-day humans. For example, the catalog includes differences in genes that code for functional elements, such as proteins, in which the Neanderthal versions are more like those of the chimpanzee than present-day humans. Some evolutionary changes were found in known genes involved in cognitive development, skull structure, energy metabolism, skin morphology and wound healing.
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http://genome.gov/27539119
I think this might be the best topic to present it. The National Human Genome Research Institute on May 2010: Complete Neanderthal Genome Sequenced- DNA Signatures Found in Present-Day Europeans and Asians, But Not In Africans.
