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peer review demolishes Winters M-173
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[QUOTE]Originally posted by Troll Patrol # Ish Gebor: [QB] [QUOTE]Phylogenetic Tree of Global Mitochondrial DNA Every person alive today can trace their maternal lineage to a single woman who lived in Africa approximately 160,000 years ago. She has been called the "Mitochondrial Eve" - there is no relation at all to the biblical Eve. As our ancestors migrated out of Africa and settled in Europe, Asia and the Americas, mutations occurred that became part of the genetic make-up of particular geographical populations. This diagram depicts how these mutations led to branching in the phylogenetic tree of mtDNA. The letters in boxes represent mitochondrial haplogroups, or "clans", that are comprised of people with similar lineages. The numbers on the lines are positions within the mitochondrial genome at which polymorphisms (mutations) are found that define the haplogroup. The numbers next to some of the boxes are approximate coalescent times, i.e., the time in the past that the haplogroup originated. Coalescent times are in thousands of years (Kivisild, 2006). [/QUOTE] http://www.cagetti.com/Genetics/reportmtdna.pdf [QUOTE] Distribution of variation in mtDNA genomes among human populations Compared to the estimates based on autosomal data the observed differences in mitochondrial sequences among human populations on a global scale are significantly higher and second only to the differences based on Y chromosomes, with Africa showing the highest within region diversity and Native Americans having the lowest [56]. As it has been repeatedly shown with ever increas- ing sample sizes that are reaching tens of thousands of individuals now [68], the root of the mtDNA phylogeny and the most diverse branches are restricted to African populations (Figure 2). Using the maximum molecular resolution enabled by the analysis of whole mtDNA ge- nomes, the first seven bifurcations in this tree, in fact, define the distinction of strictly sub-Saharan African branches (L0-L6) from those that are shared by Africans and non-African populations. Analyses of whole mtDNA sequences of sub-Saharan Africans have revealed early, ca 90 to 150 thousand years (ky) old divergence of the L0d and L0k lineages that are specific to the Khoisan populations from South Africa and it has been estimated that during this time period at least six additional line- ages existed in Africa with living descendants [53,54]. In contrast to the overall high basal clade diversity and geographic structure some terminal branches from haplogroups L0a, L1c, L2a, and L3e show recent co- alescent times and wide geographical distribution in Africa, likely due to the recent Bantu expansion [70-72]. [...] The fact that virtually every non-African mtDNA lineage derives from just one of the two sub-clades of the African haplogroup L3 (Figure 2) has been inter- preted as an evidence of a major bottleneck of mtDNA diversity at the onset of the out of Africa dispersal [74]. The magnitude of this bottleneck has been estimated from the whole mtDNA sequence data yielding the esti- mates of the effective population size which range be- tween several hundred [75] and only few tens of females [56]. The separation of these two sub-clades, M and N, from their African sister-clades in L3 can be dated back to 62 to 95 kya [48] whereas the internal coalescent time estimates of the M and N founders have been estimated in the range of 40 to 70 ky [26,28,75] and suggest that their dispersal occurred probably after rather than before the eruption of Mount Toba 74 kya in Indonesia, one of the Earth’s largest known volcanic events in human his- tory. Archaeological evidence from Jurreru River valley, India, has shown the presence of artefacts right above and below the layers of ash associated with the Toba eruption [76]. It is not clear whether the makers of these artefacts were archaic or anatomically modern humans. As in case of the global TMRCA estimate considered above the wide error ranges around the age estimates of haplogroups M and N reflect primarily the uncertainties of the mutation rate - in relative terms, the age estimates of M and N, as determined from whole mtDNA se- quences form approximately one third of the total depth of the global mtDNA tree. Claims for relatively recent, post-Toba, time depth of the non-African founder- haplogroups have been recently supported by the aDNA evidence of the 45 kya Ust-Ishim skeleton whose whole mtDNA sequence falls at the root of haplogroup R [50]. While haplogroups M and N are widely spread in Asia, Australia, Oceania and Americas, the geographic distri- bution of each of their sub-clades has more specific re- gional configuration (Figure 2). [/QUOTE]--Kivisild Investigative Genetics (2015) 6:3 DOI 10.1186/s13323-015-0022-2 Maternal ancestry and population history from whole mitochondrial genomes http://www.investigativegenetics.com/content/pdf/s13323-015-0022-2.pdf http://www.phylotree.org [/QB][/QUOTE]
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