The basques They are a unique population within Western Europe, since their language has no relation to any other Indo-European. In addition, genetically they have been considered to have different characteristics. Even so, until now there was no conclusive study that explained the origin of its peculiarity.
Now, an international research team led by the Pompeu Fabra University (UPF) has confirmed that the genetic uniqueness of the Basques is the result of their genetic continuity from the Iron age, characterized by periods of isolation and lack of gene flow, and not of its external origin compared to other Iberian populations.
The cultural language barrier could promote the isolation of the Basque population from subsequent population contacts, such as the influence of the Roman Empire or the Islamic occupation of the peninsula.
The research, which has been led by David comas, principal investigator at UPF and at the Institute of Evolutionary Biology (IBE / CSIC-UPF), has included the geographic sampling the most comprehensive so far of the Basque population, with more than 600,000 genetic markers throughout the entire genome for each individual.
The result of the multidisciplinary study, which has included a team of linguists and geneticists, reveals in the journal Current Biology that the cultural barrier of language it was able to promote the isolation of the Basque population from subsequent population contacts, such as the influence of the Roman Empire or the Islamic occupation of the peninsula, and even acted as an internal barrier in some cases due to the use of dialects.
“The sampling included micro-regions within the Basque Country and also the surrounding areas. In this way, we obtained samples from a geographical region where Basque has always been spoken, others where it has historically been spoken, but has been lost, and regions where it has never been spoken ”, he points out. André Flores-Bello, first author of the article. It also highlights that “the study is a clear example of the importance of the interaction between different disciplines such as linguistics, the genetics and the archaeological evidence at the time of reconstructing our history ”.
Color representation of the mixture and genetic structure in the Basque Country; the green symbolizing the Basques, and the blue and red blends it with the surrounding populations. / André Flores-Bello.
Genetic differences within the Basque Country
In the work they have compared the Basque population with other current European populations and also with data from Ancient DNA. The results show that the Basques have a genetic composition similar to the rest of the Western European populations, but they present slight differences. These are due to a lack of gene flow since the Iron Age, that is, there has been less mixing with other populations.
David Comas, professor of Biological Anthropology of the Department of Experimental and Health Sciences (DCEXS) at UPF, details that “we did not find, for example, influence from North Africa that is seen in most populations of the Peninsula nor is there the trace of other migrations such as Romanization ”.
Within the Basque Country they have observed that those populations that are geographically closer to each other are more genetically similar
On the other hand, they have also addressed the question: How genetically different are the Basques from each other? Within the Basque Country they have observed that those populations that are geographically closer to each other are more genetically similar. This correlation between genetics and geography is common, since the populations that are closest to each other have had a shared history.
What is unique in this case is that there is much compartmentalization within an extremely small geographic region, which is unusual for populations of this size. This genetic heterogeneity corresponds to the dialects of the Basque.
“Until now it was thought that these were formed from the Middle Ages but we postulate that they may have arisen much earlier and that is why they are related to genetic structure”, explains David Comas, head of the Human Genome Diversity group at IBE.
With the new existing methodologies we are increasingly able to reconstruct stories on a smaller scale. “The large number of markers and samples that we use together with computational sophistication allow us to solve questions that until now we could not address and open the door to the knowledge of the most local and most recent history of our species ”, concludes the expert.
Fountain: IBE (CSIC-UPF)
Rights: Creative Commons.