Ancient DNA: reconstruction of the biological history of Aldaieta necropolis

The research work began with the extraction and subsequent analysis of DNA from the ancient remains (normally by the sequencing of mitochondrial DNA, a molecule inherited maternally) of each individual and in duplicate. Moreover, a third copy of the sample from each individual was sent to another laboratory and. finally, they compare all of them in order to distinguish between what is endogenous from what is the result of handling. Obviously, the results obtained from the same sample/individual have to tally in all the analyses in order to be reliable.

Interpretation of the settlement at Aldaieta

Despite the problems inherent working with ancient DNA, the methodology drawn up for the current work as well as the precautions and criteria of authentication undertaken have enabled reliable and verifiable results of the population buried at Aldaieta to be obtained.

Within the great homogeneity of the mitochondrial lines on the European continent, the genetic substrate of the population buried at Aldaieta falls within the variability of that expressed by current populations on the Cantabrian coast and Atlantic axis, thereby indicating the existence of genic flow between these human groups in ancient times.

Besides the characterisation of the mitochondrial genome, they have carried out the characterisation of the chromosome Y, using techniques focused on ancient DNA, an have shown the existence of family relationships within the necropolis, given that certain mitochondrial lines have a particular distribution, the grouping of individuals belonging to the same line having been discovered at nearby burial sites. Besides, there exists a significant differentiation gender wise, men having qualitatively and quantitatively more important funerary artefacts than women.

It is clear that the genetic analysis of skeleton remains, despite the labour-intensive work involved and the problem of authenticity of the results, has provided an essential contribution in the reconstruction of the biological history of human populations.