Without knowing it, and cut the DNA, the Argentines carrying a message of their ancestors. And in 56% of cases which he bequeathed he wrote just a single fact: Amerindian origin. Of the current population, 44% down on all of European ancestry, but the rest-the majority-has a partially or totally indigenous lineage. So found a study by the Department of Genetic Fingerprinting at the University of Buenos Aires, based on analysis of cases in 11 provinces. "What is revealed is that we are not as European as we be," says Daniel Corach, director of the Service, a professor in the department of Genetics and Molecular Biology, Faculty of Pharmacy and Biochemistry, UBA and CONICET researcher. In a second stage, with Andrea Sala, a researcher at the CONICET, and Miguel Marino, a fellow in that institution-analyzed pure Aboriginal communities.

Beginning in 1992, and taking DNA samples at random from a total of 12 000 people, scientists were able to get by the thread of the skein of genes to reconstruct the history of the population living in our country. They wanted to know how the native population had contributed to the formation of modern Argentina. Now, with the study ended, it seems like a lot.

The analysis involved reading codes inscribed in mitochondrial DNA, which provide all mothers, and the Y chromosome, which only men and bequeath their parents. And that during the marriage not be combined to create a new being, remain unchanged in the different generations.

The Argentine researchers, in charge of the study, they knew where to look in that puzzle of genetic codes. The method used is not new. Used since the mid-90s and is reduced to a cell. In fact its nucleus and mitochondria, two sites are DNA molecules. For, finally, everything is focused on the acronym that designates a molecule consisting of two chains of chemical units (adenine, thymine, guanine and cytokines). Where they are located depends on the message. We should think about as an alphabet of four letters that form words. The message body realizes.

In the long line forming combinations, Y, is a known marker with initials and numbers: DYS199. There, in the case of Native Americans, there is a typical feature, and scientifically proven "that carry all the members of that community, which took place in much of Argentine men. But this genetic trait, the scientists, not necessarily manifested in some visible physical trait. "Thus you were able to sustain long believed that most of Argentina's population is of European origin," said Corach.

Then the team looked in a particular area of mitochondria, also in a region that remains unchanged and is identified as HVR I. The result was as expected: the majority of the sample had no native Amerindian upward. That is, had mostly European mothers (53.3%).

The combined data gave crossing and there was that in 56% of cases had an Indian heritage somewhere in the DNA. In this segment of the population, only 10% were pure Amerindian, European component no.

The surprise for Corach explained: "It is believed that two major massacres of Aboriginal people ended up with 30,000 people. It is assumed that there were more people. Probably what happened is that they had offspring that is present yet. I think he overestimates the European component. "

The scientist maintains that "the study sample is representative because it includes the urban population but only of the Federal Capital," he explains. "If we look to the people of Barrio Norte will give us a high percentage of European origin."

The method started from a scientific breakthrough: the last few years knows that part of the story is recorded in the genetic material that carry humans. And this allows us to reconstruct the famous novel "where we come" of humanity.

At first he could only be done with the material provided by women, which is in the mitochondria. Hence the controversial revelation that the mothers of all men was the "mitochondrial Eve," an African woman. In the mid-nineties, it was possible to analyze the male component, enrolled in the Y Chromosome

Now Corach and company want to find out how to move this population. Meanwhile, the founding myth is questioned. Should we remove that part of the travel guides and encyclopedias say that over 85% of Argentina's population is of European origin? 

Silvina Heguy. 
sheguy@clarin.com