Overview
R1a-Z645 is the crucial branching point that produced the two massive global expansions of R1a: Z283 in Europe and Z93 in Asia. It formed around the time when early steppe pastoralist societies were undergoing rapid innovation, mobility and cultural transformation. Z645 likely originated in populations connected to the forest-steppe zones of Eastern Europe or the Volga–Ural corridor.
The descendants of Z645 became foundational for two of the largest Bronze Age cultural spheres: the European Corded Ware complex and the Sintashta–Andronovo horizon. These expansions influenced the spread of Indo-European languages, horse-based warfare, chariot technology and large-scale mobility across Eurasia. The phylogenetic split between Z283 and Z93 mirrors the divergence between European and Indo-Iranian Indo-European language families.
Geographic distribution
Z645 is ancestral to populations across Europe and Asia. Its daughter clades form major paternal components in Eastern Europe, Scandinavia, Central Asia, Iran and South Asia.
Ancient DNA
- Corded Ware individuals show strong Z283 ancestry under the Z645 trunk.
- Sintashta and Andronovo populations overwhelmingly belong to Z93, the Asian branch of Z645.
- Bronze Age samples from the Volga–Ural region indicate early Z645 diversification.
- Late Neolithic steppe individuals show basal Z645 lineages.
Phylogeny & subclades
Z645 splits rapidly into two major branches: Z283 (European) and Z93 (Asian). These lineages form the largest and most geographically widespread branches of R1a.
Notes & context
R1a-Z645 is the single most important node for understanding the Indo-European expansions from the Eurasian steppe.
References & external links