Overview
G-Z725 represents one of the key internal branches within the P303-derived radiation and is phylogenetically placed close to both G-L497 and G-Z1903 but forms a distinct early divergence. While not as numerically dominant as L497 or U1, Z725 is deeply rooted in the Near East–Caucasus zone and extends into southeastern and central Europe through early agricultural expansions.
This lineage is characterized by dual regional structure: a Near Eastern core with deep diversity (especially in northern Mesopotamia, eastern Anatolia and the southern Caucasus) and a European cluster associated with early Holocene farmer migrations. Its modern frequency is modest but its phylogenetic depth makes it a crucial lineage for reconstructing early P303 population structure and differentiating pre-Neolithic from early-Neolithic expansions.
Geographic distribution
Z725 appears at its highest diversity in the Near East and the Caucasus, especially in Armenia, eastern Turkey, northern Iraq and northwest Iran. In Europe, Z725 is dispersed at low to moderate frequencies, mostly along Balkan–Carpathian–central European routes associated with early farmer movements. Western European presence is limited but includes scattered individuals in France, Italy, Spain and the British Isles.
The pattern indicates that Z725 originated in or near the northern Fertile Crescent and expanded into Europe through early Neolithic migration routes while retaining strong foothold diversity near its presumed homeland.
Ancient DNA
- Chalcolithic individuals in eastern Anatolia show SNP profiles consistent with early Z725-derived lineages.
- A small number of Neolithic Balkan individuals show upstream P303 variations compatible with Z725 ancestry.
- Later prehistoric samples across the Caucasus yield markers consistent with Z725-related branches, supporting long-term highland continuity.
Phylogeny & subclades
Z725 is a branching node within the early diversification of P303, forming sister relationships with L497, U1 and Z1903. Its internal splits include regional Caucasus–Anatolia branches and more compact European branches showing post-Neolithic founder effects. Many microclades have been identified exclusively through modern WGS but correspond strongly to geographic clusters.
Its phylogeny helps clarify the early branching order within the P303 macro-expansion, providing structure to the deepest part of the G2a2b2a tree.
- Z725* basal branches
- Caucasus–Anatolia microclades
- European founder clusters
- Multiple private or family-level branches via WGS sequencing
Notes & context
G-Z725 is essential for interpreting the early diversification of P303 before large-scale Neolithic migrations. Its survival across both Near Eastern and European regions suggests it was part of the earliest layers of the Neolithic paternal substrate, even if it later underwent only moderate expansions compared to other major branches.
References & external links