Overview
I2c2 represents the Zagros-oriented downstream branch of I2c. Its roots lie in early Holocene forager groups occupying the northern Zagros, the Lake Urmia basin and the western fringes of the Iranian Plateau. These populations contributed genetically to the broader Iranian Neolithic ancestry layer but retained their own paternal diversity, within which I2c2 appears to have been a small but persistent lineage.
I2c2 is important for illustrating that the early Iranian Neolithic was not homogeneous and included multiple paternal elements predating agriculture. The presence of I2c2 helps connect the I2 radiation to Southwest Asian mountainous ecological zones that historically served as refugia and contact corridors.
Geographic distribution
Modern instances of I2c2 occur at very low frequencies in northwest Iran, northern Iraq, eastern Turkey and occasionally the southern Caucasus. Rare outliers in southeastern Europe reflect ancient or medieval period movements along trade networks connecting Anatolia and the Balkans.
Ancient DNA
- Neolithic genomes from the Zagros region reveal complex ancestry, within which rare I2c2-like paternal signals are possible though not yet directly confirmed.
- Pre-Neolithic foragers in the region likely harbored small I2c2 lineages interacting with CHG-related and Iran Neolithic-related genetic strata.
- Later Bronze Age individuals in northwest Iran occasionally exhibit upstream I2 signatures compatible with I2c2 ancestry.
Phylogeny & subclades
I2c2 divides into a small number of downstream microbranches that likely reflect isolated forager groups within the western Iranian highland system. Due to low modern representation, phylogenetic resolution remains limited but distinct enough to justify its placement.
- I2c2a – northwest Iran microclades
- I2c2b – Zagros upland remnant lineages
Notes & context
I2c2 adds an essential layer to the deep pre-agricultural ancestry of the Iranian Plateau. Including it in the atlas makes the I2 story more complete by extending it eastward into Southwest Asia.
References & external links