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[QUOTE]Originally posted by Troll Patrol # Ish Gebor: [QB] [QUOTE]Originally posted by the lioness,: [qb] [QUOTE]Originally posted by Troll Patrol # Ish Gebor: [QUOTE]Originally posted by the lioness. [IMG]http://www.ephotobay.com/image/world-slin-tone.png[/IMG][/URL] World Skin Tone Chart -also depending on amount of time a population has been living at a particular latitude [/qb][/QUOTE] http://www.egyptsearch.com/forums/ultimatebb.cgi?ubb=get_topic;f=8;t=008651;p=1#000000 The dolo get's to a point where it just becomes ridiculous. [/QB][/QUOTE]so you are of the opinion that skin tone has no relation to a popualtion's long term proximity to the equator ? [/QB][/QUOTE]I am of the opinion that what you type and fetch as truth is mostly pure B.S.. [QUOTE] In this study, we investigated the most likely origin of haplogroup L lineages of African origin in Europe. Given the criteria of autochthony used coupled with the results yielded by the analysis of ancestry based on AIMs, we could rule out (at least in our samples) the bias that recent immigrants could have introduced in the results. A large proportion (65%) of the African-European mtDNAs investigated could be attributed to modern and well-documented demographic routes that existed during the Romanization period, the Arab conquest, and the trans-Atlantic slave trade. However, there is strong evidence pointing to the fact that the remaining 35% of the L-European mtDNAs stand as modern witnesses of sporadic population movements occurring between the two continents that might have begun as early as 11,000 yr ago (Fig. 5). These contacts were not only restricted to North Africa, but connected sub-Saharan regions to Europe directly via coastal routes or first crossing North African territories toward the Mediterranean Sea. Previous studies (Achilli et al. 2005; Ottoni et al. 2010; Pereira et al. 2010) provided evidences of mtDNA flow from Europe toward North Africa during the Holocene; thus, North Africa would represent the Southern African edge of post–Last Glacial Maximum expansions spreading from European refugee. Here, we show, for the first time, genetic evidence signaling prehistorical movements in the opposite direction, from sub-Saharan Africa toward Europe. It is likely that most of the signals in the nuclear genome of this ancestral gene admixture between African immigrants and local Europeans had been erased by historical recombination and genetic drift. Therefore, as demonstrated in the present study, the mtDNA genome (and perhaps the Y chromosome) (Capelli et al. 2009) is the source to rescue the echoes of prehistorical sub-Saharan movements into Europe. [IMG]http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3337428/bin/821fig5.jpg[/IMG] Diagram showing the coalescence ages of L-European lineages and their 95% C.I. (see also Supplemental Table S2) and the estimated frequencies in Europe over the total number of existing L mitochondrial genomes from Europe. [IMG]http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3337428/bin/821fig3.jpg[/IMG] The pie charts on the left indicate the frequency distribution of African haplogroups in Europe; the color circles within the map indicate the distribution of entire genomes in Europe clustered in main haplogroups. The pie charts on the right show the admixture components of L-European lineages in Africa. [IMG]http://i59.tinypic.com/16iciko.jpg[/IMG] [i]Spatial haplogroup distribution of sub-Saharan African lineages in Europe based on control-region data. (A) Macro-haplogroup L; (B) haplogroup L1b. Green crosses in A indicate the sampled regions (see also Supplemental Data S1).[/i] [b]However the remaining 35% of L mtDNAs form European-specific subclades, revealing that there was gene flow from sub-Saharan Africa toward Europe as early as 11,000 yr ago.[/b] Results The phylogeny of European haplogroup L mitogenomes The phylogenetic relationships of the 56 novel and 13 previously reported L mi- tochondrial genomes from Europe are reported in Supplemental Figure S1. Sev- eral novel minor L haplogroups that are not present in Africans (or in African- Americans) were detected. This finding, together with the fact that these haplo- groups show a certain level of molecular divergence, suggests that these branches could have evolved within Europe. One of the most singular European haplogroup L subclades is L3d1b1a, defined by the stable diagnostic transversion A8014C (Soares et al. 2009). We found L3d1b1a exclusively in Italy (five subjects from Tuscany, Umbria, and Campania) (Supplemental Table S1), thus most likely it evolved in situ. All individuals carried different haplotypes suggesting local divergence dating back to 3.6 kya (95% C.I.: 2.2–5.1) (Supplemental Table S2). Malyarchuk et al. (2008) recently proposed that the subclade L2a1k, defined by the mutational motif G6722A-T12903C- C16218T-T16519C, could have originated in Europe ;10,300 6 5150 yr ago. We have built a maximum parsimony tree using all available L2a1 entire mtDNA sequences (Supplemental Fig. S2; Supplemental Table S3). Our data provide further support to the finding of Malyarchuk et al. (2008) because we did not observe representatives of L2a1k in our collection of African sequences (n = 2426). We also searched L2a profiles carrying the diagnostic con- trol-region variant C16218T in a large survey of African control-re- gion sequences (>13,700), but no potential L2a1k candidates were observed. However, it is important to note that variant C16218T could be a misleading diagnostic marker for L2a1k. Two of our samples from Benin and Cameroon carrying this variant were completely se- quenced and attributed to different clades, L2a1c8 and L2a1d (Sup- plemental Data S1; Supplemental Fig. S2). The TMRCA for L2a1k of 10.6 kya (95% C.I.: 9.9–11.3) is very similar to the previous estimate (Malyarchuk et al. 2008). L1b is by far the most common L-African lineage in Europe, 49% according to complete mitogenomes (a total of 34, of which 30 are newly reported here), and 23% according to control-region data. Previous studies mainly based on control-region sequences (Salas et al. 2002) showed that haplogroup L1b is most frequent and diverse in West-central Africa (Fig. 1). To further evaluate haplogroup L1b mtDNAs, we collected 73 L1b entire genomes (mainly from Africans and African-Americans) from the literature and GenBank, which together with the 30 novel sequences from Europe sum to 103 (Supplemental Table S4). The phylogeny of the 103 L1b mitogenomes is provided in Figure 2. The vast majority of the non-European lineages were sampled in North America (African-Americans and Hispanics; n = 40) and West-central Africa (n = 13), the latter being the most likely source for the majority of the L1b mtDNAs in America (Salas et al. 2005). Control-region data indicate that L1b haplotype di- versity is highest in East Africa, but the values of nucleotide diversity and the average number of nucleotide differences are highest in Western Africa (Bight of Biafra) (Supplemental Table S5). Demographic movements from sub-Saharan Africa could have spread L1b to the North (;1% and ;5% in Northeast and Northwest Africa, respectively). Given the phylogeny, the frequency, and the diversity pat- terns observed in Africa for L1b, it is likely that this haplogroup arose in West Africa, from where it moved to other African and non-African locations. There is a subclade of L1b defined by the transition A16289G (Fig. 2) and named here L1b1a2a, which could have originated later in East Africa (represented by three divergent sequences from Ethiopia: GenBank accession numbers EU092952, EU092942, and EU092950). L1b1a2a could have moved from East Africa to the North downstream the Nile shores toward Egypt (repre- sented by the complete genome EU092775). The immediate ancestral node, L1b1a2 (Fig. 2), is represented by a single mitogenome observed in Israel (the Bedouin sequence EU092672) (Behar et al. 2008). There are two representatives of L1b1a2a in Spain (one of them in Galicia; Northwest Spain), which could have arrived during the period of the Atlantic slave trade or the Arab invasion of the Iberian Peninsula. We have also identified a new subclade of L1b1a, here named L1b1a9, characterized by the transversion G185C and the transi- tion T14040C (Fig. 2). In contrast to most of the L1b subclades, L1b1a9 has a clear North African and Mediterranean distribution. It perhaps originated in Northwest Africa (as represented by the Moroccan Jew sequence EU092667) and afterward moved to different European Mediterranean locations (mainly Iberia and Italy). Two L1b1a9 sequences were found in Iberia (Galicia and Cata- lonia), three in the Italian Peninsula, and one in France. [/QUOTE]--María Cerezo et al. Reconstructing ancient mitochondrial DNA links between Africa and Europe http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3337428/ [/QB][/QUOTE]
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