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The Max Planck Institute for Evolutionary Anthropology and the MPI-EVA 454 Life Sciences Corporation announced at the annual meeting of the American Association for the Advancement of Science (AAAS), and simultaneously at a press , which have completed the first draft of the Neanderthal genome.

The project was made possible thanks to funding from the Max Planck Society, is headed by Prof. Svante Pääbo, director of the Department of Evolutionary Genetics of the MPI-EVA. Pääbo and his colleagues have sequenced more than 1 billion pieces of DNA extracted from Neanderthal fossil from Croatia, using new methods developed for this project. The sequence of the Neanderthal genome will clarify the evolutionary relationships between humans and Neanderthals as well as help in identifying the genetic changes that enabled modern humans to leave Africa and spread around the world about 100,000 years ago.

The Neanderthals are the closest relatives of modern humans. They lived in Europe and parts of Asia to extinction for over 30,000 years or less. For over 100 years, paleontologists and anthropologists have sought to discover their relationship to modern humans. Pääbo, a pioneer in the study of ancient DNA, made his first contribution to our understanding of genetic relationship with the Neanderthals in 1997 when he sequenced Neanderthal mitochondrial DNA. Along with the company 454 Life Sciences, Pääbo has now announced a new achievement in research on Neanderthals. The two groups have sequenced a total of over 3 billion bases of Neanderthal DNA, thus generating a first draft of the genome sequence of the Neanderthal. All together the fragments of DNA corresponding to 60% of the entire Neanderthal genome. These DNA sequences can now be compared with previously sequenced genomes of human and chimpanzee, to have an idea of how the extinct Neanderthal genome differs from that of modern humans.

In 2006, the group published Pääbo with 454 Life Sciences articles showing that it was possible to use technology to identify 454 large quantities of nuclear DNA from the late Pleistocene animals such as mammoths and Neanderthals. Based on these results, Dr. Pääbo and Michael Egholm, vice president of research and technology of 454 Life Sciences (company owned by Roche), launched an ambitious project to sequence the genome of the Neanderthal. The two groups together have overcome numerous technical difficulties so we can give a first look at the complete genome of an extinct human.

An essential element developed by the group Pääbo was the production of genomic libraries under conditions of "clean-room", which prevents contamination of the experiments with human DNA. They also designed DNA tags are unique identifiers that are linked to the ancient DNA molecules in the "clean-room". This procedure makes it possible to avoid contamination from other sources during the process of DNA sequencing, which was a problem in the initial trial experiment conducted in 2006. The group also used Pääbo tiny amounts of radioactive DNA tagging to identify and modify the steps of the procedure for sequencing DNA, where losses occur. Thanks to these and other developments implemented during this project, the need for valuable fossil was reduced drastically, which caused less than half a gram of bone were used to produce this first draft of the 3 billion base pairs.

To reliably compare the Neanderthal DNA sequences with those of human and chimpanzee, the Leipzig group has made detailed studies have identified where you are located chemical damage that occur in ancient DNA and how these damaging errors in DNA sequences. The researchers found that these errors occur more frequently towards the end of the molecules and that the vast majority of them are caused by a particular modification of one of the bases of DNA that occurs in fossil remains. Then they applied this knowledge to identify which of the DNA fragments belonging to the Neanderthal genome and what to microorganisms that have colonized the bones for thousands of years that they remained buried in the caves where they were found. Researchers also have developed new computational algorithms, more precisely, in order to allow the fragments of Neanderthal DNA in comparison with the human genome.

In total, the group has determined the sequence of more than 100 million pieces of DNA from 454 fossils using technology and over one trillion Solexa technology with another sequencing technology that is particularly efficient in the sequencing of many short sequences length. Most of the sequences from Neanderthal bones found in the Vindija cave in Croatia. These bones are studied by the group as part of a long-term collaboration between the Croatian Academy of Arts and Sciences and Academy Berlin Bradenburg. To assess whether the findings made with this Neanderthal is also typical of other Neanderthals, researchers have also sequenced several million base pairs of Neanderthal sites. Professor Javier Fortea and colleagues from Oviedo, Spain, have excavated bones of Neanderthal 43,000 years under sterile conditions in Sidrón, Spain, which have produced DNA sequences. Also Dr. Lubov and Dr. Vladimir Golovanov Doronichev St. Petersburg, Russia, have contributed to 60-70000 years for bones from the cave Mezmaiskaya in the Caucasus. In addition, Dr. Ralf Schmitz of LVR-Landesmuseum in Bonn, Germany, has allowed a sample has been removed from Nendertal of 40,000 years that define this species, originally found in the Neander Valley in 1856, the source Neandertal name. This will enable the key findings are verified in Croatian Neanderthal Neanderthals several, including the specimen that defines the Neanderthals as a different group.

To analyze the genome of the Neanderthal, Dr. Pääbo has organized a consortium of researchers from several places in the world, which plans to publish their results this year. The consortium will pay particular attention to genes of interest in recent human evolution as FOXP2, which is involved in language and speech; locus microcephalin and Tau-1, implicated in brain aging and development respectively. It has been suggested that variants of two genes, which are in modern humans, from the Neanderthal. Preliminary results suggest that Neanderthals contributed by far with a very small portion of the variation found in contemporary human populations.