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DNA studies if black amazigh im Morocco
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[QUOTE]Originally posted by Ish Gebor: [QB] [QUOTE]Originally posted by the lioness,: [qb] [QUOTE]Originally posted by typeZeiss: [s this looking specifically at black amazighs? [/QUOTE]The Amazigh groups on Morocco contain a variety of skin colors and hair types within each one so you are not going to find a study on "black amazighs". The term Hartania (Haratin) is used for Southern Moroccan groups of the Tata region who are strongly mixed with black populations. Little is known about their origins. [/qb][/QUOTE][QUOTE] [b]The Berbers constitute the main genetic background of the North African population as a whole even though in historical times several substantial migrations occurred into the region from Middle Eastern populations and elsewhere. Migrations during the historical period enriched the North African populations rather than replaced them. For many markers analyzed, North African populations display intermediate frequencies between European and African populations, possibly reflecting ancient as well as known historical admixture along with genetic drift. During the thousands of years of development a variety of populations contributed at different levels not only to allelic diversity of North Africa but also to different amounts of linkage disequilibrium between markers that are physically close to one another. Recombination events over many human generations should have generated new haplotypes that should be specific to the North African region; see Supporting Information Figures S14, S15 for some examples. [/b] [...] DISCUSSION The PCA (Fig. ​(Fig.2),2), STRUCTURE (Fig. ​(Fig.3)3) and population tree (Fig. ​(Fig.6)6) results on 65 populations clearly show that the Tunisian and Libyan populations in North Africa represent a distinctive regional pattern of human genetic variation in the context of a broad sampling of human populations worldwide. Similar PCA and STRUCTURE analyses on a subset of 90 polymorphisms that add an additional seven populations from elsewhere in North Africa (Morocco to Egypt) generate comparable results (Supporting Information Figs. S3–S6). The more focused STRUCTURE results on 40 populations (Fig. ​(Fig.5)5) studied on 299 polymorphisms do not reveal any additional subclustering within the North African area for the genetic variation sampled by the 399 autosomal SNPs in this study. In the context of worldwide variation the Tunisian and Libyan groups appear to be very homogeneous. However, PCA analyses limited to North Africa and also North Africa with some SW Asian groups as outliers (Supporting Information Figs. S18–S21) reveal that even within the relatively small zone represented by Tunisia the local populations are different from one another. Including the seven North African populations from Henn et al. (2012) in similar restricted PCA analyses (based on 90 polymorphisms) also provides evidence of the diversity of the populations within the North African region (Supporting Information Figs. S22, S23), although no simple geographical patterns emerge. A reasonable ancient settlement scenario for North Africa–based on various studies with different types of markers could be proposed as follows. Berbers arose from ancient events across North Africa with various sub‐regional differences. The autosomal SNPs analyzed here are not able to give a clear picture of what those pre‐historic events were. The Berbers constitute the main genetic background of the North African population as a whole even though in historical times several substantial migrations occurred into the region from Middle Eastern populations and elsewhere. Migrations during the historical period enriched the North African populations rather than replaced them. For many markers analyzed, North African populations display intermediate frequencies between European and African populations, possibly reflecting ancient as well as known historical admixture along with genetic drift. During the thousands of years of development a variety of populations contributed at different levels not only to allelic diversity of North Africa but also to different amounts of linkage disequilibrium between markers that are physically close to one another. Recombination events over many human generations should have generated new haplotypes that should be specific to the North African region; see Supporting Information Figures S14, S15 for some examples. Along with recombination, some specific and founder mutations, also described in the published literature, are in agreement with a common and ancient North African genetic background. All these demographicevents lead to the findings in the present study that North Africa constitutes a distinct population genetic entity. Population migrations within and between the geographical regions during pre‐history and historical times have certainly made North Africa a cross‐road of change—culturally and genetically. The positioning of the North African groups studied near the core of the tree is consistent with this. The heterozygosity evidence is supportive of a complex history for North African populations. Divergent theories on the peopling of North Africa exist to explain the accumulated evidence from different research areas. There are those who say that a civilization radiated to North Africa 40,000 years ago built by the Aterian, after which North Africa was depopulated (see the introduction to Rando et al., 1998). Indeed, uniparental genetic data support the arrival of sub‐Saharans around 20,000 years ago according to Frigi et al. (2010). Other studies show that the introduction of sub‐Saharan mtDNA lineages in North Africa is older than 30,000 YBP (Soares et al., 2012). The mixture between Iberian and sub‐Saharan Saharan populations was described in papers such as Periera et al. (2010), but more studies are needed to substantiate that mixture. The set of 399 autosomal SNPs studied here on 65 populations were not specifically selected to differentiate the Tunisian and Libyan populations representing North Africa from populations in other regions of the world. The DNA markers genotyped on the eight populations from North Africa had already been typed on the 57 reference populations. They are a subset of markers that had accumulated across a number of research projects and were originally selected for study most often because they had been shown to be highly heterozygous on average in most regions of the world or sometimes in a particular geographical region. The STRUCTURE analyses (Supporting Information Fig. S6) on 73 populations (with 15 populations sampled across North Africa) reinforce the idea that North Africa is not only genetically diverse but also a distinctive world region for human variation. More systematic studies—better, denser sampling of populations across North Africa as well as larger DNA marker sets—will likely be interesting and they will also make it easier to identify subsets of markers that differentiate North Africa from other world regions as well as markers that may show distinctive patterns within North Africa. Small, efficient sets of SNPs and other classes of DNA markers emerging from such efforts would be of benefit in a variety of areas such as anthropological research of normal human variation and ancestry, medical studies searching for common disease‐related mutations, and forensic applications identifying human remains in natural and man‐made disasters such as airline crashes, battle field casualties, and the victims and perpetrators of terrorist bombing events. Such work can also help fine tune studies that throw more light on the evolution of modern human populations. Recent studies (Henn et al., 2012; Bekada et al., 2015) have already supported the role of migrations during pre‐history and more recent eras affecting the development of human populations in North Africa. Botigué et al. (2013) explored the evidence for gene flow from North Africa and its possible effect on genetic variation in southern Europe. If, as some recent papers have suggested (Osborne et al., 2008; Balter, 2011), early human waves of migration out of Africa could have originated in part from North Africa before the formation of the Sahara desert, then the only way to help validate this is via empirical evidence that characterizes the autochthonous genome patterns still discernible in current day populations from across North Africa so that they can be compared to the descendant groups in other world regions. Broad‐based evidence is needed. Simple characterizations of groups and regions based on limited initial information is understandable, but will need to be updated and new perspectives obtained by additional analyses. For example, Sanchez‐Quinto et al. (2012) characterize the Tunisian population as homogeneous and inbred based on a small relatively inbred Tunisian sample reported by Henn et al. (2012); but that broad characterization is now untenable in the context of our more extensive sampling of populations in Tunisia which shows that the Henn et al. Tunisian sample is something of an outlier for Tunisia as a whole. North Africa is certainly not the only world region deserving more intensive study by population genetics. The present study and other recent studies by Henn et al. (2012) and Fadhlaoui‐Zid et al. (2015) indicate that the effort has the potential to yield important new understanding of the genetic history of North Africa and adjacent regions. [/QUOTE]--Sabeh Frigi, Lotfi Cherni et al. Genetic variation in Tunisia in the context of human diversity worldwide AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 161:62–71 (2016) One can only wonder who is truly mixed. :D [/QB][/QUOTE]
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