Genomic diversity and structure of prehistoric alpine individuals from the Tyrolean Iceman's territory.

Abstract

The Eastern Italian Alps played a crucial bridging role between Mediterranean and Northern alpine populations since Prehistory. However, few prehistoric individuals from that region have been genomically analysed so far. Among them, the Iceman (Copper Age, 3368-3108 BC) showed a relatively high Anatolian-Neolithic-related ancestry and low Hunter-Gatherers (HGs)-related ancestry. To investigate how the genomic structure of alpine groups varied over time and to contextualize the Iceman, we analysed 47 alpine individuals dated from the Mesolithic (6380-6107 BC) to Middle Bronze Age (1601-1295 BC). The Mesolithic genome reveals genetic admixture between Western and Eastern HGs that occurred from ~13700 - 8300 BC. Most individuals from the Neolithic onwards present a genomic structure resembling that of the Iceman, supporting genetic continuity. Few individuals carry different ancestries, such as the Steppe-related ones appearing ~2400 BC. Finally, the study suggests local and non-local admixture events between HGs and Neolithic farmers from this alpine area.