Overview
J1-ZS420 is a downstream subclade of the major Arabian-centered J1-L147.1 lineage. Its formation corresponds to demographic shifts occurring during the late Neolithic and early Bronze Age, when pastoral specialization and increased mobility shaped tribal landscapes across the Arabian Plateau. Populations ancestral to ZS420 took part in the gradual expansion of desert-adapted pastoral communities that formed the core of the early North Arabian tribal sphere. During the Bronze and Iron Ages, ZS420-bearing groups contributed to the cultural and demographic networks that linked northern Arabia with the southern Levant, Mesopotamia and the Gulf. The phylogenetic structure of the lineage indicates multiple founder effects and regionally coherent microbranches, suggesting strong ties to tribal groups active during the late prehistoric and early historic eras.