Overview
I2a1j (Y23845) is a Carpathian–eastern Balkan oriented branch of the I2a1 radiation. It emerged among late Mesolithic foraging populations inhabiting regions along the lower Danube, the eastern Carpathian foothills and the northern Balkans. This lineage reflects isolated refugial continuity followed by limited integration into early Neolithic cultures. Compared to the rapidly expanding Dinaric and Slavic-associated I2a1b branches, I2a1j shows modest growth and a strongly regional signal.
Geographic distribution
Modern carriers occur at low to moderate frequencies across Romania, Moldova, Bulgaria, Serbia and western Ukraine. Additional presence in Hungary and Greece reflects historical Balkan connectivity. Minor frequencies in the Caucasus and Anatolia likely represent ancient population movement rather than recent immigration.
Ancient DNA
- Iron Gates Mesolithic individuals show upstream variation ancestral to I2a1j.
- Early Neolithic sites in Romania and Bulgaria contain I2a lineages phylogenetically adjacent to the Y23845 root.
- Bronze Age genomes from the Carpathian Basin demonstrate continuity with deep I2 structures tied to I2a1j's geographic zone.
Phylogeny & subclades
I2a1j is a parallel branch to other I2a1 sublineages such as I2a1a, I2a1c and I2a1h. Its defining SNPs Y23845, Y23847 and BY18392 outline a clade with shallow downstream radiation and strong geographic localization.
- I2-Y23847
- I2-BY18392
- Basal I2a1j*
Notes & context
I2a1j provides insight into the persistence of pre-agricultural paternal lineages in the Carpathian–Balkan region and is valuable for modeling continuity between Mesolithic foragers and early Neolithic groups.
References & external links