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DNA studies if black amazigh im Morocco
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[QUOTE]Originally posted by the lioness,: [QB] http://www.egyptsearch.com/forums/ultimatebb.cgi?ubb=get_topic;f=8;t=009537 [QUOTE]Originally posted by the lioness,: http://www.sciencedirect.com/science/article/pii/S0002929716304487 [QUOTE] excerpts: [b]Chad Genetic Diversity Reveals an African History Marked by Multiple Holocene Eurasian Migrations[/b] Marc Haber1, , , Massimo Mezzavilla1, 2, Anders Bergström1, Javier Prado-Martinez1, Pille Hallast1, 3, Riyadh Saif-Ali4, Molham Al-Habori4, George Dedoussis5, Eleftheria Zeggini1, Jason Blue-Smith6, 10, R. Spencer Wells7, Yali Xue1, Pierre A. Zalloua8, 9, Chris Tyler-Smith1, , Show more http://dx.doi.org/10.1016/j.ajhg.2016.10.012 [b]Understanding human genetic diversity in Africa is important for interpreting the evolution of all humans, yet vast regions in Africa, such as Chad, remain genetically poorly investigated. Here, we use genotype data from 480 samples from Chad,[/b] the Near East, and southern Europe, as well as whole-genome sequencing from 19 of them, to show that many populations today derive their genomes from ancient African-Eurasian admixtures. We found evidence of early Eurasian backflow to Africa in people speaking the unclassified isolate Laal language in southern Chad and estimate from linkage-disequilibrium decay that this occurred 4,750–7,200 years ago. It brought to Africa a Y chromosome lineage [R1b-V88] whose closest relatives are widespread in present-day Eurasia; we estimate from sequence data that the Chad R1b-V88 Y chromosomes coalesced 5,700–7,300 years ago. This migration could thus have originated among Near Eastern farmers during the African Humid Period. We also found that the previously documented Eurasian backflow into Africa, which occurred ∼3,000 years ago and was thought to be mostly limited to East Africa, had a more westward impact affecting [b]populations in northern Chad, such as the Toubou, who have 20%–30% Eurasian ancestry[/b] today. We observed a decline in heterozygosity in admixed Africans and found that the Eurasian admixture can bias inferences on their coalescent history and confound genetic signals from adaptation and archaic introgression. ________ We detected the earliest Eurasian migrations to Africa in the Laal-speaking people, an isolated language group of fewer than 800 speakers who inhabit southern Chad. We estimate that mixture occurred 4,750–7,200 ya, thus after the Neolithic transition in the Near East, a period characterized by exponential growth in human population size. _________ The closest related Y chromosome groups today are widespread in Eurasia and have been previously associated with human expansions to Europe.39 and 40 We estimate that the Eurasian R1b lineages initially diverged 7,300–9,400 ya, at the time of the Neolithic expansions. However, we found that the African and Eurasian R1b lineages diverged 17,900–23,000 ya, suggesting that genetic structure was already established between the groups who expanded to Europe and Africa. R1b-V88 was previously found in Central and West Africa and was associated with a mid-Holocene migration of Afro-asiatic speakers through the central Sahara into the Lake Chad Basin.8 In the populations we examined, we found R1b in the Toubou and Sara, who speak Nilo-Saharan languages, and also in the Laal people, who speak an unclassified language. This suggests that R1b penetrated Africa independently of the Afro-asiatic language spread or passed to other groups through admixture. _____________ [b] In addition to the early Eurasian migration to Africa ∼6,000 ya, a second migration ∼3,000 ya affected the Toubou population in northern Chad but had no detectable genetic impact on other Chadian populations. This migration appears to be associated with the previously reported Eurasian backflow into East Africa, given that the source populations and dates of mixture are similar. Occurring at the start of the Iron Age, these migrations could have been facilitated by advances in warfare and transportation technology in the Near East. It is uncertain why the impact of this migration in Chad affected only the Toubou. [/b] [/QUOTE][/QUOTE]This 20-30% Eurasian ancestry of the Toubou is similar in percentage to African Americans but from different sources and time periods. Numbering about 0.5 million over four countries they are not berbers They speak the Tebu languages, in the Saharan branch of the Nilo-Saharan language family. As per the Tuareg: [IMG]https://i.imgbox.com/iqb2rZlq.png[/IMG] ^ The lowest estimate is 2000 in Tunisia, 1987 The population of Tuareg in Chad is lower than that and didn't make it to this chart. In Southern Libya where the Tuareg and Toubou are in military conflict as we can see in the videos in the thread Libya's Quiet War: The Tuareg of South Libya http://www.egyptsearch.com/forums/ultimatebb.cgi?ubb=get_topic;f=8;t=009550 We can see comparatively that the Turaeg look part Eurasian while the Toubou look virtually entirely African. The two groups have different DNA. The Turaeg have E-M81 and high frequencies of mtDNA Haplogroup H but which has higher diversity outside of Africa and is believed to have originated in Anatolia or Near East and is the most common mtDNA haplgroup in Europe. The Toubou on the other hand carry mtDNA L. They have a reverse situation. Their Y DNA is R1b. Often one can predict the phenotype to an extent corresponding to phenotype. However this branch of R1b called V88 or R1b1c is peculiar in that R1b is all over Europe yet the Africans of the R1b1c clade aka V88 don't resemble Europeans at all. Perhaps several thousand years ago when a Eurasian back flow of R1b is believed to have occurred they did look more like the mixed looking Libyan Tuareg but since then now look entirely Africa. The Tuareg are nomadic and thus look more varied. The lower caste Bella are in fact the largest part of the Tuareg population. The ancestry in the region is very complex and varied. The most African looking Tuareg are in Niger, the country with by far the largest Tuareg population. If one is looking for "black amazigh" that is a good place to start [/QB][/QUOTE]
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