Overview
Haplogroup R-Y3769 is one of the more regionally concentrated downstream branches of R2a, forming during the early to middle Holocene and likely arising within the mountainous corridor spanning the Iranian Plateau, the Zagros foothills and parts of eastern Anatolia. Its placement within the R2a phylogeny suggests that it split from upstream ancestors that were themselves undergoing geographic differentiation tied to the adoption of early agriculture and mixed agro pastoralism. Modern frequency patterns show a strong association with populations in Iran, Armenia, eastern Turkey and the broader South Caucasus region. This distribution contrasts with the major South Asian R2a expansions and indicates a western oriented pathway of diversification. Y3769 may represent a lineage maintained by relatively isolated highland communities, which favored continuity of older paternal lines even as surrounding lowland populations experienced greater demographic turnover. The middle Holocene timing of Y3769 aligns with key archaeological developments in the Near East, including the expansion of early metalworking, long distance obsidian exchange and the growth of proto urban settlements. Although no ancient samples are yet assigned to Y3769, multiple upstream R2a lineages in early Iranian and Caucasian sites suggest ancestral continuity with the environments where Y3769 likely emerged. As a western R2a branch, Y3769 helps balance the general South Asia focused narrative of R2 by demonstrating that the lineage also established deep time depth in the Near East and Transcaucasia. For genetic atlases aiming to show the full breadth of R2 diversification, Y3769 is an essential inclusion.