Description

Haplogroup I2 is the dominant paternal lineage in the Balkans and is common across Eastern Europe. It is most frequent in Bosnia (71%), Croatia (38%), and Serbia (35%), and is found at notable levels in Ukraine, Romania, and Poland. The major subclade I2a2 — also called I-CTS10228 or colloquially 'Dinaric' — experienced a dramatic population bottleneck and subsequent explosive expansion in the Balkans after approximately 2,000 BCE, a pattern many researchers link to the expansion of Slavic-speaking populations during the Migration Period (5th–7th centuries CE). An older branch, associated with Mesolithic European hunter-gatherers, is found at high frequencies in Sardinians.

Interesting Fact

The 'Dinaric' subclade I-CTS10228 displays a classic star-shaped phylogeny consistent with a severe population bottleneck followed by rapid demographic expansion approximately 2,000 years ago — a genetic signature many researchers connect to the explosive Slavic migrations of the 5th to 7th centuries CE.

Distribution by Ethnicity

Ethnic distribution Region Frequency Sample
Bosniaks Southeastern Europe
71%
Croats Southeastern Europe
38%
Serbs Southeastern Europe
35%
Sardinians Southern Europe
34%
Romanians Eastern Europe
28%
Ukrainians Eastern Europe
22%
Poles Eastern Europe
17%
Czechs Central Europe
14%

Associated Clans & Tribes

Tribe
Early Slavs
Eastern / Southeastern Europe
Migration Period Slavic expansion (5th–7th centuries CE) strongly linked to the demographic explosion of I-CTS10228
Tribe
Balkan hunter-gatherers
Balkans
Mesolithic relict population whose I2 lineages survived the Neolithic and Bronze Age population turnovers

Tags

References

  1. Rootsi et al. (2004) — Phylogeography of Y-chromosome haplogroup I reveals distinct domains of prehistoric gene flow in Europe. American Journal of Human Genetics 75(1), 128–137.
  2. Underhill et al. (2010) — Separating the post-Glacial coancestry of European and Asian Y chromosomes within haplogroup R1a. European Journal of Human Genetics 18, 479–484.
  3. Mirabal et al. (2010) — Y-chromosome distribution within the geo-linguistic landscape of northwestern Russia. European Journal of Human Genetics 17, 1260–1273.