Y-Chromosome Haplogroup I
Haplogroup I is the oldest major haplogroup in Europe, having been likely to develop around 25,000 years ago in Europe. This haplogroup can be found throughout south-eastern and central Europe. Relatively high concentrations exist in two distinct regions of Europe: among Scandinavian populations and those in the north-western Balkans. Some studies suggest that up to 40 to 50 percent of the men in Nordic populations of Scandinavia belong to haplogroup I. A similar frequency is found around the Dinaric Alps, a mountain chain in southern Europe spanning areas of Slovenia, Croatia, Bosnia and Herzegovina, Serbia and Montenegro, and Albania. Relatively high frequencies are also observed in some parts of southern France and Normandy.
- I1: I1 is thought to have emerged from the I macro-haplogroup around 20,000 years ago in Scandinavia. It is very common among Scandinavians, where it typically exists in 35% of men. This association with Scandinavian ancestry means that it is found in all places which were invaded by ancient Germanic tribes and Vikings.
- I2: I2 is thought to have emerged around 22,000 years, perhaps in the Caucasus or Anatolia. It is a major lineage in most Slavic countries, but is also found at lower frequencies in other parts of Europe.