Research into the male ancestral origins of the current population of Iberia
Research into the male ancestral origins of the current population of Iberia and Balearic Islands using Y-DNA analyses
A very interesting scientific article about research into the male ancestral origins of the current population of Iberia and the Balearic Islands using Y-DNA analyses has recently been published (Adams et al., The Genetic Legacy of Religious Diversity and Intolerance: Paternal Lineages of Christians, Jews, and Muslims in the Iberian Peninsula, The American Journal of Human Genetics (2008), doi:10.1016/j.ajhg.2008.11.007) (hyperlink: http://www.cell.com/AJHG/abstract/S0002-9297(08)00592-2)http://www.cell.com/AJHG/abstract/S0002-9297(08)00592-2). The research uses Y-DNA analyses for determining the impact of two distinct populations, North Africans and Sephardic Jews, on the current male population of Iberia.
The abstract of the article reads as follows:
“Most studies of European genetic diversity have focused on large-scale variation and interpretations based on events in prehistory, but migrations and invasions in historical times could also have had profound effects on the genetic landscape. The Iberian Peninsula provides a suitable region for examination of the demographic impact of such recent events, because its complex recent history has involved the long-term residence of two very different populations with distinct geographical origins and their own particular cultural and religious characteristics North African Muslims and Sephardic Jews. To address this issue, we analyzed Y chromosome haplotypes, which provide the necessary phylogeographic resolution, in 1140 males from the Iberian Peninsula and Balearic Islands. Admixture analysis based on binary and Y-STR haplotypes indicates a high mean proportion of ancestry from North African (10.6%) and Sephardic Jewish (19.8%) sources. Despite alternative possible sources for lineages ascribed a Sephardic Jewish origin, these proportions attest to a high level of religious conversion (whether voluntary or enforced), driven by historical episodes of social and religious intolerance, that ultimately led to the integration of descendants. In agreement with the historical record, analysis of haplotype sharing and diversity within specific haplogroups suggests that the Sephardic Jewish component is the more ancient. The geographical distribution of North African ancestry in the peninsula does not reflect the initial colonization and subsequent withdrawal and is likely to result from later enforced population movement more marked in some regions than in others plus the effects of genetic drift.”
I am hesitant to summarise the abstract in plain English because the article has been written by experts for experts and is difficult to understand for an non-expert as myself. If I understand the abstract correctly almost 11% respectively 20% of the current male population of Iberia and the Balearic Islands seems to descend from North Africans and Sephardic Jews respectively.