Overview
I2a2b (L38) represents a central European oriented branch of I2a2 that has played a subtle but consistent role in the deep paternal ancestry of the Rhine Danube interaction zone. It appears in ancient individuals from central Europe, including late Mesolithic and early Neolithic sites, where it reflects local forager ancestry that was absorbed into expanding farming populations.
I2a2b did not undergo the same broad expansions as I2a2a, but its long term persistence makes it particularly important for detecting local continuity in the central European landscape. Its downstream branches reveal small but meaningful founder effects in Germany, Switzerland and surrounding regions during the Neolithic and Bronze Age.
Geographic distribution
Modern I2a2b is found in low to moderate frequencies across Germany, Switzerland, Austria, the Czech Republic and parts of France. Small traces appear in Belgium and the Low Countries. It is less common in Scandinavia and the British Isles compared to I2a2a.
Its distribution generally reflects ancient central European ancestry rather than later historical expansions.
Ancient DNA
- Late Mesolithic and Early Neolithic individuals from Germany and Switzerland include lineages related to I2a2b.
- I2a2b appears in Neolithic contexts influenced by LBK and post LBK cultures, representing local forager absorption.
- Bronze Age central European individuals sometimes carry downstream I2a2b branches, indicating regional continuity.
Phylogeny & subclades
I2a2b separates into a series of microbranches that correspond to central European founder effects. Its phylogeny is less extensive than I2a2a but shows meaningful geographic clustering.
- I2a2b1 – central European clusters
- I2a2b2 – Alpine and upper Rhine microbranches
Notes & context
I2a2b is essential for reconstructing the paternal prehistory of central Europe and detecting the survival of pre Neolithic ancestry in the region.
References & external links