Overview
J2a-PF5174 is a major early trunk within the J2a-L26 radiation and represents one of the key internal branches that structure the deeper diversity of J2a across West Asia. It likely arose during the terminal Pleistocene or very early Holocene among groups living along the interface between the northern Fertile Crescent, the Zagros foothills and eastern Anatolia. At this time, ancestral J2a populations occupied a mosaic of ecological niches ranging from upland oak–pistachio woodland to riverine corridors and semi-arid steppe. PF5174 marks a split within this ancestral population that eventually gave rise to several regionally focused sublineages extending from the south Caucasus and northern Mesopotamia toward Anatolia, the Levant and, via later movements, parts of Central and South Asia.
Unlike downstream, more geographically restricted clades (such as specific Mediterranean or South Asian offshoots), PF5174 represents a broad ancestral structural node that predates many of the classic archaeological cultural packages we associate with J2a today. Early PF5174-bearing communities were not yet farmers in the full sense but were deeply involved in the transition from foraging and broad-spectrum subsistence to incipient cultivation and animal management. As agriculture and herding became entrenched during the Pre-Pottery Neolithic and early Pottery Neolithic, PF5174 lineages were absorbed into and helped shape the paternal genetic substrate of highland and piedmont populations across northern Mesopotamia, eastern Anatolia and the Iranian Plateau margin.
Geographic distribution
Modern distributions of PF5174-derived lineages show a core zone extending from western and northwestern Iran (particularly the Zagros front) through northern Iraq and southeastern Turkey into Armenia and the south Caucasus. In these regions, PF5174 often co-occurs with other highland-oriented J2a lineages (such as Z6055- and PF5197-derived clades) as well as with G2a, J1-Z1828, R1b-Z2103 and various L and T branches, forming a characteristic highland West Asian paternal palette.
Secondary distributions of PF5174 are found in central and western Anatolia, in the northern and central Levant, on Cyprus and around parts of the Aegean basin (including mainland Greece and some islands). These occurrences are best interpreted as products of Neolithic and later Chalcolithic/Bronze Age movements emanating from the north Mesopotamian–Anatolian–Zagros interaction sphere. Lower but non-trivial frequencies in Central Asia, Afghanistan, Pakistan and northwest India likely represent Bronze and Iron Age eastward expansions of Iranian-plateau–related populations carrying PF5174-derived subclades, subsequently integrated into local demographic histories.
Ancient DNA
- Early Neolithic populations in the Zagros region and northern Mesopotamia, associated with early goat domestication and mixed agro-pastoral economies, show J2a-L26 signatures that can be phylogenetically placed close to the PF5174 trunk in modern high-resolution trees.
- Chalcolithic communities from northwest Iran and the upper Tigris–Euphrates corridor contain J2a haplotypes that appear to descend from PF5174-like ancestors, forming part of the paternal background of early metallurgical and trade centers.
- Bronze Age highland groups in eastern Anatolia and the Armenian plateau, particularly those associated with pre–Kura–Araxes and early Kura–Araxes cultural horizons, show J2a diversity that includes branches aligning with PF5174 and its immediate descendants.
- Later Bronze and Iron Age assemblages from northern Mesopotamia, the south Caucasus and the eastern Mediterranean occasionally yield J2a chromosomes whose closest modern parallels lie among PF5174-derived lineages, indicating continued involvement of this clade in regional population dynamics.
Phylogeny & subclades
Within the internal topology of J2a-L26, PF5174 occupies a deep, structurally important node that splits off relatively early from the main ancestral trunk. It is parallel in time depth to other PF-series lineages such as PF5160, PF5169, PF5121 and PF5197, together forming a cluster of early J2a branches that underlie much of the later J2a diversity. PF5174 itself contains multiple subclades, many of which show strong regional clustering. Some are centered on the Zagros and western Iran; others have their highest diversity in eastern Anatolia and Armenia; still others exhibit Mediterranean-facing expansions, with representation in the Aegean and Levant.
Because PF5174 is upstream of many regionally structured branches, it functions as a key reference node: when ancient DNA is resolved only to deep J2a levels, the PF5174 trunk provides a framework for inferring whether that ancestry is more compatible with a highland Iranian/Anatolian source versus a coastal Mediterranean or South Asian focus.
- J2a-PF5174* – rare basal lineages in western Iran, northern Iraq and eastern Anatolia
- PF5174 > highland Zagros–Armenian plateau clusters with long-term continuity in upland valleys and basins
- PF5174 > north Mesopotamian and upper Tigris–Euphrates microclades associated with early agro-pastoral settlements
- PF5174 > Aegean and eastern Mediterranean spillover branches linked to Neolithic and Bronze Age maritime networks
- PF5174 > minor eastward offshoots in Iran, Central Asia and northwest South Asia
Notes & context
J2a-PF5174 is an underappreciated but foundational branch within the J2a phylogeny. Many early studies that reported unresolved J2a or J2a-L26* lineages in the highlands of Iran and Anatolia almost certainly included PF5174-derived chromosomes. For a synthetic atlas treatment, PF5174 should be regarded as one of the principal highland-oriented J2a trunks, closely tied to the emergence of early West Asian farming societies and to subsequent highland–lowland interaction systems that linked the Zagros, Armenian plateau, northern Mesopotamia and eastern Anatolia.
References & external links