Hunter with blue eyes and dark skin... 7,000 years ago

Question

DNA analysis of an individual of some 7,000 years ago, whose remains were discovered in 2006 on the site of the brane - Arintero (LeÃ_n), said it had blue eyes, as the current European, and dark skin, as Africans. It would be a hunter -gatherer before the advent of agriculture and animal husbandry. An international team led by Carles Lalueza Fox, a researcher at the Higher Council for Scientific Research (CSIC), has managed to extract DNA from a tooth that individual baptized the brane 1 and now presents its results in the journal Nature (advancing in article Internet).

The brane 1 represents the first genome of a European hunter-gatherer recovered and is the oldest so far Prehistoric says the CSIC. At the site were the remains of two men, but researchers have just obtained and analyzed, for the moment, the DNA of one of them.

The hunter -gatherer Leon lived in the Mesolithic period between 10,000 and 5,000 years and ends with the advent of agriculture and animal husbandry, from Middle east.

"The arrival of the Neolithic, with a carbohydrate-based diet, and new pathogens transmitted by domesticated animals, marked metabolic and immune challenges were reflected in genetic adaptations of post- Mesolithic populations. Among these is the ability to digest lactose, the guy did not have the brane ", experts say. Nature emphasizes that selective processes involved in this crucial transition to agriculture are not well understood.

"The biggest surprise was that this guy had the African versions in the genes that make up the light pigmentation of Europeans today, indicating he had dark skin, although we can not know the exact tone," says Lalueza -Fox, great international expert on ancient DNA, who works at the Institute of Evolutionary biology (CSIC- UPF) in Barcelona. " Even more surprising was the discovery that had the genetic variants that produce blue eyes in Europeans today," he adds.

Nature highlights the fact that, in view of these results, the transition to lighter skin tone would occur even in the Mesolithic, and the change of eye color is earlier.

The genome study suggests that current closer to the brane locations are one of northern Europe, such as Sweden and Finland, explains the CSIC. The data also indicate that " there is genetic continuity of populations of central and western Eurasia," adds Lalueza -Fox, also highlighting the line with the information obtained in the archaeological record.

Iñigo Olalde, researcher at the Institute of Evolutionary Biology, said that the team will try to recover the DNA of the second individual, the brane 2, which is worse preserved to continue to obtain information on the genetic characteristics of these ancient Europeans.