Haplogroup I2 (Y-DNA)

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Haplogroup I2
Time of origin	probably >15 kya (see subclade descriptions)
Place of origin	Southeastern Europe
Ancestor	I
Descendants	I2a I2b (see subclade descriptions)
Defining mutations	M438/P215/S31
Typical members	I2a1 Croatia Bosnia I2a2 Sardinia Basques I2b1 Germany Netherlands Denmark England

In human genetics, Haplogroup I2 is a Y-chromosome haplogroup. Until 2008, it was formerly known as Haplogroup I1b.

1 Subclades
- 1.1 I2a1
- 1.2 I2a2
- 1.3 I2b*
- 1.4 I2b1
2 See also
3 External links
4 References
5 Relationship to haplogroups and subclades

[edit] Subclades

Note: The systematic subclade names have changed several times in recent years, and they are likely to change again, as new markers are discovered which clarify the sequence of branching of the tree.

The scheme below is taken from ISOGG 2008^[1], which updates Karafet et al (2008).^[2] Earlier schemes can be found at ISOGG 2007^[3] and ISOGG 2006.^[4]

I2 (M438/P215/S31) (formerly I1b)

I2a (P37.2) (formerly I1b1)
- I2a*
- I2a1 (M423)
  - I2a1a (P41.2/M359.2) (formerly I1b1a)
- I2a2 (M26) (formerly I1b1b)
  - I2a2*
  - I2a2a (M161) (formerly I1b1b1)
I2b (M436/P214/S33, P216/S30, P217/S23, P218/S32) (formerly I1b2)
- I2b*
- I2b1 (M223, P219/S24, P220/S119, P221/S120, P222/U250/S118, P223/S117) (formerly I1b2a - old I1c)
  - I2b1*
  - I2b1a (M284) (formerly I1b2a1)
  - I2b1b (M379) (formerly I1b2a2)
  - I2b1c (P78) (formerly I1b2a3)
  - I2b1d (P95) (formerly I1b2a4)

[edit] I2a1

I2a1 is typical of South Slavs, especially Croats and Bosnians (40 - 50%). The high frequency and diversity of Haplogroup I2a1 among populations of the Western Balkans lends support to the hypothesis that the Adriatic region of modern-day Croatia served as a refuge for populations bearing Haplogroup I2a1 during the last glacial maximum. The subclade divergence for P37.2 occurred 10.7±4.8 kya (Rootsi 2004). The age of YSTR variation for the P37.2 subclade is 8.0±4.0 kya (Rootsi 2004). The age of YSTR variation for the M423 subclade is 8.8±3.6 kya (Underhill 2007).

[edit] I2a2

Haplogroup I2a2 accounts for approximately 40% of all patrilines among the Sardinians^[5]. It is also found at low to moderate frequency among populations of the Basque Country and Iberia. The age of YSTR variation for the M26 subclade is 8.0±4.0 kya (Rootsi 2004).

[edit] I2b*

Haplogroup I2b* was found in the skeletal remains of Lichtenstein Cave, a Bronze Age archeological site in central Germany associated with artifacts of the Urnfield culture ^[6]. Of the 19 males represented in the cave, 15 yielded the full 12 tested STR values, with twelve showing I2b*, one R1b, and two R1a. Of the 21 females in the cave, the majority were mtDNA H, with mtDNA U5b the runner-up. No radio-carbon dating was discussed and no metrics were assigned based on the adult remains, which are thought to be about 3000 years old. The small sample and their possible familial connections do not permit drawing conclusions regarding the overall contemporary population mixture. However, the cave lies at the center of the area predicted to be high in historical I2b population density based on statistical analysis of current population DNA.

[edit] I2b1

The distribution of Haplogroup I2b1 is closely correlated to that of Haplogroup I1 except in Fennoscandia, which suggests that it was probably harbored by at least one of the Paleolithic refuge populations that also harbored Haplogroup I1; the lack of correlation between the distributions of I1 and I2b1 in Fennoscandia may be a result of Haplogroup I2b1's being more strongly affected in the earliest settlement of this region by founder effects and genetic drift due to its rarity, as Haplogroup I2b1 comprises less than 10% of the total Y-chromosome diversity of all populations outside of Lower Saxony. The distributions of Haplogroup I1 and Haplogroup I2b1 seem to correlate fairly well with the extent of historical influence of Germanic peoples. Haplogroup I2b1 has been found in over 4% of the population only in Germany, the Netherlands, Belgium, Denmark, England (not including Wales or Cornwall), Scotland, and the southern tips of Sweden and Norway in Northwest Europe; the provinces of Normandy, Maine, Anjou, and Perche in northwestern France; the province of Provence in southeastern France; the regions of Tuscany, Umbria, and Latium in Italy; and Moldavia and the area around Russia's Ryazan Oblast and Republic of Mordovia in Eastern Europe. One subclade of Haplogroup I2b1, namely I2b1a (M284), has been found almost exclusively among the population of Great Britain, suggesting that the clade may have a very long history in that island. Of historical note, both haplogroups I1 and I2b appear at a low frequency in the historical regions of Bithynia and Galatia in Turkey, possibly descendants of the ancient Gauls of Thrace, several tribes of which are recorded to have immigrated to those parts of Anatolia at the invitation of Nicomedes I of Bithynia. Haplogroup I2b1 also occurs among approximately 1% of the Sardinians. The subclade divergence for M223 occurred 14.6±3.8 kya (Rootsi 2004). The age of YSTR variation for the M223 subclade is 13.2±2.7 kya (Rootsi 2004) and 12.3±3.1 kya (Underhill 2007).