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So Southern Europeans are North Africans....
--- Genetic ancestry of a Moroccan population as inferred from autosomal STRs - K. Bentayebi
Discussion Our study of the autosomal STR variation supports the hypotheses of a recent common ancestor between North Africa and Southern Europe (Morjani et al., 2011). The deviation of Arabic Tunisian was of particular concern. This paper describes the pattern of the frequency distribution of 15 polymorphic STR of the autosomal chromosomes in the Moroccan population.
The hierarchical AMOVA analysis showed that only a small and non-significant part of the genetic variance could be attributed to the variation between East and West groups (FCT = 0.30%), indicating no particular genetic differentiation between both sides and arguing for a shared middle eastern ancestry. Botigué et al. have previously studied population relationships in the western and eastern Mediterranean basin using genome-wide SNP data from more than 2000 individuals. This survey indicated that Southwestern European population average between 4% and 20% of their genomes assigned to a North African ancestral whereas this value does not exceed 2% in southeastern European populations. They also found that migration event from North Africa to Europe would have occurred at least 6–10 generations ago (∼240–300 ya) in Spain, and at least 5–7 generations ago in France and Italy. In the other hand, SNP data showed that the haplotype sharing between Europe and the Near East follows a southeast to southwest gradient, whereas sharing between Europe and the Maghreb follows the opposite pattern (Botigué et al., 2013; Henn et al., 2012); this suggests that gene flow from the Near East cannot account for the sharing with North Africa. It is possible that these patterns reflect more ancient migrations, perhaps dating back to the Neolithic, which resulted in a low level of short Near Eastern haplotypes across much of Europe. A model of gene flow from the Near East into both Europe and North Africa, such as a strong demic wave during the Neolithic, could result in shared haplotypes between Europe and North Africa.
In Europe, U6 lineage was only found in the Iberian Peninsula, pointing likely to a northward expansion from Africa (Maca-Meyer et al., 2003; González et al., 2003). This expansion could be attributed to either the Arab– Berber occupation that lasted seven centuries or to prehistoric immigrations of North Africans to Iberia (Ibn Abd-el-Hakem, 1858) probably during the Capsian diffusion in North Africa and suggesting important demographic movements in the western area of this continent. For instance and in line with our results, it was found using classical genetic markers, that the Near East showed smaller genetic distances with East Africa than with West Africa (especially Arab groups) and Iberian Peninsula (Bentayebi et al., 2011; Botigué et al., 2013; Henn et al., 2012).
The deviation of Arabic Tunisian was of particular concern. This could be explained by the history of the Tunisian population, reflecting the influence of the ancient Phoenician settlers of Carthage followed, among others, by Roman, Byzantine, Arab and French occupations, according to historical records. Notwithstanding, other explanations cannot be discarded, such as the relative heterogeneity within current Tunisian populations, and/or the limited sub-Saharan genetic influence in this region as compared with other North African areas, without excluding the possibility of the genetic drift and the small size of the sampled population.
Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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