The gastric bacterium Helicobacter pylori provides insight into the demographic and evolutionary histories of humans in Siberia and the New World, according to a study. H. pylori infects approximately half of individuals worldwide and has shared a coevolutionary relationship with humans for at least the past 100,000 years. Examining the historical journey of this bacterium could answer lingering questions about the geographic distributions and movements of human populations in Siberia and the Americas. Yoshan Moodley and colleagues collected and analyzed the DNA sequences of H. pylori strains from ethnically diverse populations across Eastern Eurasia and the Americas. The results suggest that humans persisted in Siberia during the last glacial maximum (LGM), which is the most recent time during the Last Glacial Period at which ice sheets were at their greatest extent, approximately 19,000 to 26,500 years ago. The data also indicate that populations previously isolated in central or southern Siberia during the LGM may have recolonized northern Siberia during the Holocene, which began approximately 11,650 years ago. In addition, the findings provide evidence that humans colonized the New World through a single migration of evolutionarily ancient northern Eurasians across the Bering land bridge into the Americas approximately 12,000 years ago, according to the authors.
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Article #20-15523: " Helicobacter pylori 's historical journey through Siberia and the Americas," by Yoshan Moodley Andrea Brunelli, Silvia Ghirotto, et al.
MEDIA CONTACT: Yoshan Moodley, University of Venda, Thohoyandou, SOUTH AFRICA; email: < yoshanmoodley@googlemail.com >
Proceedings of the National Academy of Sciences