New research published in The Journal of Paleogenomics has identified a unique genetic adaptation in Late Pleistocene remains from the East African Rift. The study reveals that a specific variant of the SLC4A4 gene, which regulates carbonate and fluoride transport in the kidneys and teeth, became prevalent in the population around 14,000 years ago. This provided a critical evolutionary defense against the high levels of naturally occurring fluoride in the region's volcanic groundwater.
Anthropologists suggest that this genetic selection allowed early hunter-gatherer groups to thrive in areas where fluoride toxicity otherwise caused severe skeletal and dental damage. This finding highlights the profound impact of local environmental geochemistry on the human genome and provides a new window into the physiological challenges faced by our ancestors in geologically active landscapes.