Overview
G2b3 is a newly resolved and extremely rare downstream branch of G2b identified primarily through whole-genome sequencing of isolated individuals from Pakistan, Afghanistan and the Gulf region. As one of the least populated branches of haplogroup G, G2b3 offers a window into previously unrecognized paternal lineages surviving in small tribal or clan-based contexts.
Its structure suggests a later divergence than G2b1 and G2b2, potentially associated with Bronze Age or early Iron Age expansions within South-Central Asia. The lineage is so rare that its precise ancient demographic context remains only partially understood.
Geographic distribution
G2b3 appears at extremely low frequencies in Pakistan (particularly northern and western regions), Afghanistan, and among a few individuals in the Arabian Peninsula—possibly due to medieval or early Islamic-era gene flow. Small traces may occur in Iran and Turkmenistan but require further verification.
Its rarity makes its geographic interpretation tentative, though it clearly aligns with the broader Iranian–Afghan–South Asian G2b distribution zone.
Ancient DNA
- No ancient genomes have been definitively tied to G2b3 due to its rarity.
- Upstream signals in Iron Age Afghanistan and eastern Iran occasionally resemble proto-G2b3 lineages.
- The absence of G2b3 from early Neolithic Near Eastern genomes is consistent with its later divergence.
Phylogeny & subclades
G2b3 encompasses several tiny WGS-defined microclades with strong indications of founder effects. Most branches appear to represent isolated paternal lines surviving over millennia in tribal socio-ecological niches.
- G2b3* basal
- Afghan regional microclades
- Pakistan foothill microclades
Notes & context
G2b3 highlights the value of WGS sequencing in uncovering rare paternal lineages that standard genotyping would miss. Its inclusion strengthens the completeness of the atlas and captures a thin but important sliver of South-Central Asian paternal history.
References & external links