Overview
J2a-L397 is a prominent downstream branch of J2a-M92 with a demographic concentration in the Adriatic and Aegean regions. Its formation is linked to the middle Holocene phase when farming communities were spreading along the eastern Adriatic coast, western Greece and the coastal slopes of the Balkans. These communities were already participating in maritime contact networks that connected the Adriatic, Ionian and Aegean seas. During the Bronze Age, L397 bearing lineages took part in population flows associated with the Adriatic hinterland, Mycenaean Greece and coastal western Anatolia. The clade shows clear signals of expansion during the late Bronze and early Iron Ages, a period that saw intensified mobility, colonization and interaction across the Adriatic and Aegean basins.
Geographic distribution
Modern J2a-L397 frequencies are highest in coastal Croatia, Bosnia and Herzegovina, Albania, Greece and southern Italy. It also appears in western Turkey, especially along the coast, and at lower levels in the central Mediterranean islands. Sporadic presence in western Europe and the Levant is usually linked to classical and post classical movements.
Ancient DNA
- Late Neolithic and Chalcolithic individuals from the Adriatic region show J2a patterns compatible with ancestral L397.
- Aegean Bronze Age burials include J2a lineages that overlap with early L397 diversification.
- Bronze Age sites in southern Italy and the Adriatic hinterland show J2a structures consistent with L397 related expansions.
- Classical Greek and Hellenistic colonial centers around the Adriatic display J2a variation that fits L397 derived branches.
- Roman era and medieval remains from the Adriatic coast preserve continuity with L397 bearing populations.
Phylogeny & subclades
L397 forms a set of microclades centered on the eastern Adriatic and Aegean regions. Several subbranches show strong local clustering in coastal and island populations, reflecting founder effects and limited gene flow across inland barriers. Additional branches extend into southern Italy and western Anatolia, mirroring maritime routes of the Bronze and classical periods.
- L397* basal Adriatic form
- Eastern Adriatic coastal microclades
- Greek and Aegean island branches
- Southern Italian downstream lines
Notes & context
J2a-L397 is informative for studies of population structure along the Adriatic coast and the Aegean world. It records multiple phases of maritime connectivity and local founder driven expansions.
References & external links