Taiwan Biobank data reveals ongoing natural selection in living humans

Researchers at National Yang Ming Chiao Tung University have identified evidence that natural selection is still active in modern humans. By analyzing genomic data from over 72,000 Han Taiwanese participants in the Taiwan Biobank, the study tracks how genetic variants change across different age groups.

This approach helps identify ongoing purifying selection, which is the process that removes harmful genetic variants from a population. The researchers analyzed over 500,000 genome-wide variants and found 168 that deviated from neutral expectations. Approximately 90 percent of these were rare variants, many of which are linked to serious health conditions like cancer, kidney disease, and neurological disorders.

One significant finding involves the BRCA1 gene. Researchers identified a specific rare haplotype that appears to be under purifying selection, becoming less common over time. This suggests that while some variants may increase disease risk, others might have provided advantages in different historical environments. The study also highlighted how genes like ATG9A and FADS2 affect multiple biological systems, making them central points for human physiology and natural selection.

This work provides a new framework for using national biobanks to study evolution. By applying these methods to large datasets, scientists can better prioritize mutations for clinical research and move toward more precise medical treatments. The findings demonstrate that evolution does not stop, and living populations continue to carry its imprints in their genomes.