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Investigators from the Consejo Superior de Investigaciones Científicas (CSIC) in collaboration with the German Max Planck Institute and the University of Oviedo have recovered the entire mitochondrial DNA genome of Neanderthals five. Among other findings, scientists estimate that the last common mother of all Neanderthals mitochondrial genomes, the so-called 'mitochondrial Eve' Neanderthal who lived 110,000 years ago, it would be more recent than that of modern humans, the researchers found in Africa makes 150,000.

The mitochondrial genome is the DNA that is inside the mitochondria, which has the particularity to be transmitted only by maternal line. Their analysis allows to determine the common ancestor of a species, the so-called 'mitochondrial Eve'. In this case, the analysis of the five genomes have revealed that the 'mitochondrial Eve' Neanderthal lived only 110,000 years ago. CSIC researcher Antonio Rosas, co-author of the article, says: "This date is newer than the one obtained with previous models based on the fossil record."

In reaching these conclusions, researchers analyzed the genome of five individuals, one of the Sidrón, another reservoir of Vindija (Croatia), two Feldhofer (Germany) and one of Mezmaiskaya (Russia). The authors also obtained partial sequence of the sixth individual, from the Russian site. The results indicate that genetic variation among Neanderthals is lower than among modern humans. "It has been estimated an even lower than the variability that is currently in human populations in Europe," says Rosas. "For example," the scientist continues, "two of the genomes of Feldhofer and Vindija, which are separated by almost a thousand kilometers, are identical, something that can only happen if the diversity of species is very low. "

Judging by the similarity of mitochondrial sequences separated by thousands of kilometers, the researchers believe there was no geographical structuring of populations Neanderthals, at least at the end of their evolutionary history: "The genetic data suggest that the Neanderthals formed small groups very mobile and with a low population density, "adds too CSIC researcher and coauthor of work Carles Lalueza. Researchers estimate that the total size of these populations is very low, with an effective number of females less than 3,500.

The findings, which contradict previous morphological studies, opening the door to theoretical discussion about the demographics of the Neanderthals.

For the study researchers have used new technologies ultrasecuenciación mass, which allows to study millions of DNA sequences from ancient bones. Furthermore, the protocols used in the extraction clean Sidrón produce samples with little contamination from modern humans, which facilitates analysis: sequencing Sidrón The sample has a 0.27% fixed sequence pollutants, the smallest percentage ever found for a Neanderthal sample. "With this technique it will be possible to specifically analyze thousands of genetic variants in the sample from El Sidrón and what are equal and different from what modern humans," Lalueza progresses.

The site of El Sidrón in Asturias, which was conducted excavations since 2000, has so far recovered about 1,600 skeletal remains of at least ten individuals Neanderthals. The mitochondrial genome analyzed in this study came from a splinter of bone from an adult male that was used to identify a gene associated with language (the FOXP2) gene and the ABO blood group. Furthermore, another Sidrón The sample was used to retrieve a gene for pigmentation which found that some Neanderthals had red hair.

The site of El Sidrón (Borines, Asturias) is excavated under the direction of Professor Javier Fortea, and co-field Rasillo the Framework, both from the University of Oviedo. So far have recovered more than 1,600 skeletal remains of at least ten individuals Neanderthals. The proposed excavation and study of Neanderthals by Sidrón is subsidized by the Culture of Asturias.