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Berbers are primarily not African ?
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[QUOTE]Originally posted by the lioness,: [QB] 2004 see table 1 at below link for frequency chart ______________________________________ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1181964/ [b]Phylogeographic Analysis of Haplogroup E3b [E-M215] Y Chromosomes Reveals Multiple Migratory Events Within and Out Of Africa[/b] Fulvio Cruciani,1 Abstract We explored the phylogeography of human Y-chromosomal haplogroup E3b by analyzing 3,401 individuals from five continents. Our data refine the phylogeny of the entire haplogroup, which appears as a collection of lineages with very different evolutionary histories, and reveal signatures of several distinct processes of migrations and/or recurrent gene flow that occurred in Africa and western Eurasia over the past 25,000 years. In Europe, the overall frequency pattern of haplogroup E-M78 does not support the hypothesis of a uniform spread of people from a single parental Near Eastern population. The distribution of E-M81 chromosomes in Africa closely matches the present area of distribution of Berber-speaking populations on the continent, suggesting a close haplogroup–ethnic group parallelism. E-M34 chromosomes were more likely introduced in Ethiopia from the Near East. In conclusion, the present study shows that earlier work based on fewer Y-chromosome markers led to rather simple historical interpretations and highlights the fact that many population-genetic analyses are not robust to a poorly resolved phylogeny. Two of the three branches of haplogroup E, the major clades E1 and E2, have been observed almost exclusively on the African continent, where their distribution has been analyzed in detail [Underhill et al. 2000; Cruciani et al. 2002]. The third branch, the clade E3, defined by the mutation P2, is the only one that has also been observed in Europe and in western Asia, where it has generally been found at frequencies <25% [Hammer et al. 2000, 2001; Semino et al. 2000; Scozzari et al. 2001; Cinnioğlu et Recently, it has been proposed that E3b originated in sub-Saharan Africa and expanded into the Near East and northern Africa at the end of the Pleistocene [Underhill et al. 2001]. E3b lineages would have then been introduced from the Near East into southern Europe by immigrant farmers, during the Neolithic expansion [Hammer et al. 1998; Semino et al. 2000; Underhill et al. 2001]. E-M81 is very common in northwestern Africa, with frequencies as high as 80% [Bosch et al. 2001; Cruciani et al. 2002; present study], but its frequency sharply declines on the continent toward the east, and the haplogroup is not found in sub-Saharan Africa. The distribution of E-M81 chromosomes in Africa closely matches the present area of distribution of Berber-speaking populations on the continent, suggesting a close haplogroup–ethnic group parallelism: in northwestern Africa, the lowest frequencies for this haplogroup have been reported in two Arab-speaking Moroccan populations [31% and 52% vs. 65%–80% in six Berber speaking groups from Morocco and Algeria [Bosch et al. 2001; Cruciani et al. 2002; present study]]; in Egypt, where Berbers are restricted to a few villages, E-M81 is rare [1.9%], and the southernmost finding of E-M81 chromosomes on the continent is that here reported in the Tuareg from Niger [9.1%], who also speak a Berber language. Outside of Africa, E-M81 has been observed in all the six Iberian populations surveyed, with frequencies in the range of 1.6%–4.0% in northern Portuguese, southern Spaniards, Asturians, and Basques; 12.2% in southern Portuguese; and 41.1% in the Pasiegos from Cantabria. It has been suggested [Bosch et al. 2001] that recent gene flow may have brought E3b chromosomes from northwestern Africa into Iberia, as a consequence of the Islamic occupation of the peninsula, and that such gene flow left only a minor contribution to the current Iberian Y-chromosome pool. The relatively young TMRCA of 5.6 ky [95% CI 4.6–6.3 ky] that we estimated for haplogroup E-M81 and the lack of differentiation between European and African haplotypes in the network of E-M81 [fig. 2C] support the hypothesis of recent gene flow between northwestern Africa and Iberia. In this context, our data refine the conclusions of Bosch et al. [2001] in two ways. First, not all of the E3b chromosomes in Iberia can be regarded as a signature of African gene flow into the peninsula: in our data set, 8 of 15 E-M78 chromosomes belong to cluster α, denoting gene flow from mainland Europe [see above]. Second, and more importantly, the degree of the African contribution is highly variable across different Iberian populations: the proportion of haplogroup E chromosomes of African origin [E[xE3b], E-M35*, and E-M81] was <5% in three Spanish locations; 10.0% and 14.2% in northern and southern Portugal, respectively; and >40% in the Pasiegos [table 1]. A relatively high frequency of E-M81 in a different sample of Pasiegos [18%] and non-Pasiegos Cantabrians [17%] has also recently been reported [Maca-Meyer et al. 2003]. Such differences in the relative African contribution to the male gene pool of different Iberian populations may reflect, at least in part, the different durations of Islamic influence and introgression in different parts of the peninsula, as well as drift/founder effects for the small Pasiegos group. [/QB][/QUOTE]
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