Study Reveals Ongoing Natural Selection in Modern Humans

Key Points:

• Researchers analyzed genomic data from over 72,000 Han Taiwanese adults aged 24 to 70 using an age-stratified allele frequency approach, identifying 168 genetic variants under ongoing natural selection, with 159 showing purifying selection mostly involving rare variants.
• Among these, 71 variants are classified as pathogenic or likely pathogenic in ClinVar, linked to inherited disorders including cancer, cardiovascular, neurological, and kidney diseases, highlighting the method’s ability to detect medically relevant rare variants often missed by conventional scans.
• A rare BRCA1 haplotype carrying 16 protein-altering variants is under purifying selection, while neighboring DNA repair genes BRCA2 and MLH1 show signs of positive selection, illustrating complex evolutionary trade-offs between disease risk and potential adaptive advantages.
• The study also revealed pleiotropic effects in genes such as ATG9A and FADS2 influencing multiple traits including lipid metabolism, bone density, and liver function, alongside red blood cell adaptations likely shaped by historical malaria pressure in Taiwan.
• This novel analytic framework demonstrates how large biobanks can uncover ongoing human evolution and medically significant variants within specific populations, offering new opportunities to integrate evolutionary biology with precision medicine globally.