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In human genetics, Mitochondrial Eve is the matrilineal most recent common ancestor (MRCA), in a direct, unbroken, maternal line, of all currently living humans, who is estimated to have lived approximately 100,000–200,000 years ago. This is the most recent woman from whom all living humans today descend, in an unbroken line, on their mother’s side, and through the mothers of those mothers, and so on, back until all lines converge on one person. Because all mitochondrial DNA (mtDNA) generally (but see paternal mtDNA transmission) is passed from mother to offspring without recombination, all mtDNA in every living person is directly descended from hers by definition, differing only by the mutations that over generations have occurred in the germ cell mtDNA since the conception of the original "Mitochondrial Eve". Mitochondrial Eve is named after mitochondria and the biblical Eve. Unlike her biblical namesake, she was not the only living human female of her time. However, her female contemporaries, excluding her mother, failed to produce a direct unbroken female line to any living person in the present day. Mitochondrial Eve is estimated to have lived between 99,000 and 200,000 years ago,〔. (University of Leeds – New 'molecular clock' aids dating of human migration history )〕〔 most likely in East Africa,〔('Your Genetic Journey' – The Genographic Project )〕 when ''Homo sapiens sapiens'' (anatomically modern humans) were developing as a population distinct from other human sub-species. Mitochondrial Eve lived later than ''Homo heidelbergensis'' and the emergence of ''Homo neanderthalensis'', but earlier than the out of Africa migration. The dating for "Eve" was a blow to the multiregional hypothesis and a boost to the theory of the origin and dispersion of modern humans from Africa, replacing more "archaic" human populations such as Neanderthals. As a result, a consensus emerged among anthropologists that the latter theory was more plausible. Analogous to the Mitochondrial Eve is the Y-chromosomal Adam, the member of ''Homo sapiens sapiens'' from whom all living humans are descended patrilineally. The inherited DNA in the male case is his nuclear Y chromosome rather than the mtDNA. Mitochondrial Eve and Y-chromosomal Adam need not have lived at the same time. For example, Y-chromosomal Adam has been estimated to have lived during a wide range of times from 180,000 to 581,000 years ago,〔 (primary source)〕 while a 2013 paper concluded that he lived between 120,000 and 156,000 years ago (however, this paper did not include some Cameroonians and one African American, who did not inherit their Y from that "Adam"〔). ==History== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Mitochondrial Eve」の詳細全文を読む スポンサード リンク
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