Haplogroup I-M170

refuges, 20,000 years BP. Available evidence suggests that I-M170 was preceded into areas in which it would later become dominant by haplogroups K2a (K-M2308) and C1 (Haplogroup C-F3393). K2a and C1 have been found in the oldest sequenced male remains from Western Eurasia (dating from circa 45,000 to 35,000 years BP), such as: Ust'-Ishim man (modern west Siberia) K2a*, Oase 1 (Romania) K2a*, Kostenki 14 (south west Russia) C1b, and Goyet Q116-1 (Belgium) C1a. The oldest I-M170 found is that of an individual known as Krems WA3 (lower Austria), dating from circa 33,000-24,000 BP. At the same site, two twin boys were also found, both were assigned to haplogroup I*. Haplogroup IJ was in the Middle East and/or Europe about 40,000 years ago. The TMRCA (time to most recent common ancestor) for I-M170 was estimated by Karafet and colleagues in 2008 to be 22,200 years ago, with a confidence interval between 15,300 and 30,000 years ago. This would make the founding event of I-M170 approximately contemporaneous with the Last Glacial Maximum (LGM), which lasted from 26,500 years ago until approximately 19,500 years ago. 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 24,000 ±7,100 years ago and time to population divergence as 23,000 ±7,700 years ago. 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 28,400 ±5,100 years ago, although they calculate the STR variation age of I1 at only 8,100 ±1,500 years ago. Semino (2000) speculated that the initial dispersion of this population corresponds to the diffusion of the Gravettian culture. Later the haplogroup, along with two cases of Haplogroup C, was found in human remains belonging to the previously mentioned Gravettian culture and in individuals of the Magdalenian and Azilian cultures. 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. So far, only Haplogroup F* and Haplogroup C1b have been documented, once each, on older remains in Europe. I2 subclade of I-M170 is the main haplogroup found on male remains in Mesolithic Europe, until circa 6,000 BCE, when mass migration into Europe of Anatolian farmers carrying Y-DNA G2a happened. Due to the arrival of so-called Early European Farmers (EEFs), I-M170 is outnumbered by Haplogroup G among Neolithic European remains and by Haplogroup R in later remains. The earliest documentation of I1 is from Neolithic Hungary, although it must have separated from I2 at an earlier point in time. In one instance, haplogroup I was found far from Europe, among 2,000-year-old remains from Mongolia. It would seem to be that separate waves of population movement impacted Southeastern Europe. The role of the Balkans as a long-standing corridor to Europe from Anatolia and/or the Caucasus is shown by the common phylogenetic origins of both haplogroups I and J in the parent haplogroup IJ (M429). This common ancestry suggests that the subclades of IJ entered the Balkans from Anatolia or the Caucasus, some time before the Last Glacial Maximum. I and J were subsequently distributed in Asia and Europe in a disjunctive phylogeographic pattern typical of "sibling" haplogroups. A natural geographical corridor like the Balkans is likely to have been used later by members of other subclades of IJ, as well as other haplogroups, including those associated with Early European Farmers. The existence of Haplogroup IJK – the ancestor of both haplogroups IJ and K (M9) – and its evolutionary distance from other subclades of Haplogroup F (M89), supports the inference that haplogroups IJ and K both arose in Southwestern Asia. Living carriers of F* and IJ* have been reported from the Iranian Plateau. ==Distribution==