Overview
J2b-Z42990 is a downstream element of the J2b-M241 lineage and is strongly tied to southern Balkan, Aegean and western Anatolian populations. Its early formation is associated with late Neolithic and Chalcolithic communities that occupied coastal lowlands, river valleys and island systems across the Aegean–Balkan interaction sphere. These societies built early maritime networks, developed intensive farming systems and played major roles in the diffusion of material culture across the Adriatic and Aegean corridors. By the Bronze Age, Z42990-bearing groups appear in the demographic landscape of Mycenaean coastal settlements, island-based polities, Thracian lowland centers and western Anatolian coastal zones. The clade's downstream structure suggests several microregional expansions tied to Aegean islands, southern Balkan tributary networks and Anatolian shoreline communities. Iron Age and classical populations across the region preserve J2b lineages fitting the expected distribution of Z42990, indicating long-term continuity in maritime and coastal environments.