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In human genetics, Haplogroup DE is a human Y-chromosome DNA haplogroup. It is defined by the single nucleotide polymorphism (SNP) mutations, or UEPs, M1(YAP), M145(P205), M203, P144, P153, P165, P167, P183.〔(ISOGG reference webpage. )〕 Haplogroup DE is often referred to by the most well-known unique event polymorphism (UEP) which defines it, the Y-chromosome Alu Polymorphism (YAP). The YAP mutation was caused when a strand of DNA called Alu, which copies itself, inserted a copy into the Y chromosome. A Y chromosome that has the YAP mutation is called YAP-positive (YAP+), and a Y chromosome that does not have the YAP mutation is labeled YAP-negative (YAP-). Haplogroup DE is an estimated 65,000 years old. ==Distribution== The majority of DE male lines can be categorized as being in either Haplogroup D (Y-DNA), which likely originated in Asia, the only place where it has been found,〔 or haplogroup E, which is believed to have originated in East Africa or the Near East. The remainder are said to be in the paragroup DE *, confirmed cases of which are extremely rare. DE * has been most frequently observed amongst Nigerians, albeit at a low frequency. In a study of over 8,000 men worldwide, five out of 1,247 Nigerian males were so classified. However, the study's authors have cautioned that "the apparently paraphyletic status of this haplogroup, and hence the conclusions of nested cladistic analysis, are also likely to be illusory" and that "the only genealogically meaningful definition of the age of a clade is the time to its most recent common ancestor, but only if DE * is paraphyletic does it also become automatically older than D or E in this sense." More recently, one example of DE * was possibly found among speakers of the Nalu language in Guinea Bissau (1/17). The DE * sequence of this individual differs by one mutation from the DE * sequence of the Nigerian individuals. This indicates common ancestry, though the phylogenetic relationship between the two lineages was not determined in this particular study. A 2008 study detected DE * in two individuals from Tibet (2/594).〔 The paragroup DE * in africa is probably a divergent form of E while the paragroup DE in Tibet probably is a more divergent form of D, or (possibly but not likely) this DE * may simply be a subclade of E or D with a back mutation. This has happened before for example the F * in India is really H some of the K * in Timor Melanesia is really P the NO * in China is really N and the R * in Northern pakistan is really R2 〔http://biorxiv.org/content/early/2013/11/22/000802.1〕 Haplogroup DE is found in Africa (Haplogroups E and DE *) and East Asia (Haplogroups D and DE * and E *) but is largely absent in between these two regions. The presence of DE across widely separated regions has confounded investigators trying to reconstruct the migration of humans from Africa to Asia. At some time, there was an extinction of DE lineages in West, South and Central Asia. Autochthonous DE lineages are absent in India, an important region in the dispersal of humans in Asia. However DE lineages have been detected in relict populations of the Andaman Islands. Underhill et al. 2007, suggest the possibility that deleterious mutations in some DE carriers may explain the extinction of DE lineages in India.〔 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「Haplogroup DE」の詳細全文を読む スポンサード リンク
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