Overview
Haplogroup R-Y87754 is an early diverging branch of the R2a lineage that emerged during the early-to-middle Holocene, a time when Southwest Asia and Central Asia experienced increasing demographic complexity. The formation age suggests that Y87754 developed within highland and foothill communities spread across the Iranian Plateau and southern Central Asia. These groups played a central role in the diffusion of early herding practices, seasonal transhumance routes and early metallurgical innovations. Y87754 is extremely rare today, yet shows a consistent geographic signal in Iran, Afghanistan and occasionally Turkmenistan. Its survival likely reflects long-term continuity in mountainous and semi-isolated ecological niches where demographic replacement pressures were weaker. Unlike the major South Asian expansions of later R2a branches, Y87754 remained part of a stable but relatively low-density population structure. Although ancient individuals belonging specifically to Y87754 have not yet been identified, its upstream structure aligns closely with R2a-bearing individuals from Neolithic Iran, the Chalcolithic Zagros zone and the Central Asian piedmont. These connections highlight the lineage’s importance for reconstructing the west–east genetic corridor that linked the Iranian highlands to prehistoric Central Asia.