Overview
Haplogroup R-Y87557 represents a rare but phylogenetically informative early branch within the R2a macro-lineage. Emerging during the early to middle Holocene, this lineage developed in the period following the establishment of early farming communities in the Iranian Plateau, the Zagros region and the borderlands of South and Central Asia. Y87557 marks a distinct, independently evolving paternal line that survived outside the major demographic expansions that later shaped the bulk of R2a diversity. Its modern distribution is centered on Iran, eastern Turkey, Armenia and parts of the Caucasus, with sporadic occurrences in Pakistan and Afghanistan. This western concentration sharply contrasts with the dominant South Asian orientation of most downstream R2a branches. Y87557 therefore offers important insight into the early diversification of R2a across a broad geographic range stretching from Anatolia to the Indus. Its survival in low frequencies suggests long term continuity within isolated highland communities that experienced less population turnover than surrounding lowland regions. Although no ancient DNA samples are firmly assigned to Y87557, its age and distribution match the archaeological record of early Holocene pastoral and farming groups in the Zagros and Armenian Highlands. These regions acted as genetic reservoirs where early paternal lineages could persist despite later demographic changes, making Y87557 an important lineage for reconstructing the deep structure of R2a.