Indigenous Andeans evolved more saliva amylase genes to digest potato starch
A Nature Communications study finds Indigenous Andeans in Peru have about 10 copies of the salivary amylase gene, more than the global average of seven, likely due to natural selection after potato domestication roughly 10,000 years ago. More gene copies can mean more amylase enzyme, potentially improving starch digestion; individuals with more copies had a 1.24% higher chance of surviving and reproducing, indicating a strong adaptive advantage that may have shaped this genome feature.