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In human genetics, Haplogroup I-M170 is a Y-chromosome DNA haplogroup, a subgroup of haplogroup IJ, itself a derivative of Haplogroup IJK. Y-DNA Haplogroup I-M170 is predominantly a European haplogroup and it is considered as the only native European Haplogroup.〔http://www.cell.com/ajhg/abstract/S0002-9297(07)62002-3?cc=y〕 It can be found in the majority of present-day European populations with peaks in some Northern and South-Eastern European countries where the total population is small in comparison with European standards. Consequently, the haplogroup represents not more than one-fifth of the population of Europe, being the continent's second major Y-DNA haplogroup behind Haplogroup R. Haplogroup I-M170 Y-chromosomes have also been found among some populations of the Near East, the Caucasus, Northeast Africa and Central Siberia. The haplogroup reaches its maximum frequency in the Dinaric Alps (with the highest concentration in present-day Bosnia and Herzegovina). ==Origins== Haplogroup IJ, carried by the Cro-Magnons was moving to Europe from the Middle East between 40,000 and 30,000 years ago. The TMRCA (time to most recent common ancestor) for the I clade was estimated by Karafet and colleagues in 2008 as 22.2 k.a. (22,200 years ago) with a confidence interval between 15.3-30.0 ka., placing the Haplogroup I-M170 founding event approximately contemporaneous with the Last Glacial Maximum (LGM) which lasted from 26.5 ka to 19 or 20 ka. The TMRCA is an estimate of the time of subclade divergence. Rootsi and colleagues in 2004 also note two other dates for a clade, age of STR variation, and time since population divergence. These last two dates are roughly associated, and occur somewhat after subclade divergence. For Haplogroup I-M170 they estimate time to STR variation as 24±7.1 ky and time to population divergence as 23±7.7 ky. These estimates are consistent with those of Karafet 2008 cited above. However Underhill and his colleagues calculate the time to subclade divergence of I1 and I2 to be 28.4±5.1 ky, though they calculate the STR variation age of I1 at only 8.1±1.5 kya.〔P.A. Underhill, N.M. Myres, S. Rootsi, C.T. Chow, A.A. Lin, R.P. Otillar, R. King, L.A. Zhivotovsky, O. Balanovsky, A. Pshenichnov, K.H. Ritchie, L.L. Cavalli-Sforza, T. Kivisild, R. Villems, S.R. Woodward, New Phylogenetic Relationships for Y-chromosome Haplogroup I: Reappraising its Phylogeography and Prehistory, in P. Mellars, K. Boyle, O. Bar-Yosef and C. Stringer (eds.), ''Rethinking the Human Evolution'' (2007), pp. pp. 33-42.〕 Haplogroup I is Europe's oldest major and only one whose point of origin is there, excluding European subclades of haplogroups that did not originate in Europe.〔(Haplogroup I1 (Y-DNA), 2. Origins and History )〕 Genes for blue eyes such as OCA2 were present on Mesolithic European carriers of haplogroup I, while another typical European feature, the red hair, had not been present in Europe until the Bronze Age when Haplogroup R1b carriers began spreading it.〔(Haplogroup R1b (Y-DNA), 5. R1 populations & light pigmentation )〕 Semino (2000) speculated that the initial dispersion of this population corresponds to the diffusion of the Gravettian culture. Rootsi and colleagues in 2004 suggested that each of the ancestral populations now dominated by a particular subclade of Haplogroup I-M170 experienced an independent population expansion immediately after the last glacial maximum.〔 It would seem to be that different episodes of populace movement had impacted Southeast Europe, as well as the role of the Balkans as a long-standing corridor to Europe from Southwestern Asia is shown by the phylogenetic unification of Hgs I and J by the basal M429 mutation. This proof of common ancestry suggests that ancestral Hgs IJ-M429 * probably would have entered Europe through the Balkan track sometime before the LGM. They then subsequently split into Hg J and Hg I in Southwestern Asia and Europe in a typical disjunctive phylogeographic pattern. Such a geographic hall is prone to have encountered extra consequent gene streams, including the horticultural settlers. Moreover, the unification of haplogroups IJK creates evolutionary distance from F–H delegates, as well as supporting the inference that both IJ-M429 and KT-M9 arose closer to Southwestern Asia than Central or Eastern Asia. Y-chromosomes F-M89 * and IJ-M429 * were reported to have been observed in the Iranian plateau (Grugni et al. 2012). 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 I-M170」の詳細全文を読む スポンサード リンク
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