Indigenous Peruvian Andeans show highest global AMY1 copy number from positive selection
Updated
Updated · Nature.com · May 5
Indigenous Peruvian Andeans show highest global AMY1 copy number from positive selection
7 articles · Updated · Nature.com · May 5
Researchers analysed 3,723 people from 85 populations and found Peruvian Andean groups had a median 10 AMY1 copies versus a worldwide median of seven.
Genome-wide tests and long-read sequencing indicated a selected Andean haplotype rose sharply after about 10,000 years ago, with an estimated selection coefficient of 0.0124.
The expansion coincides with potato domestication in the Andes and suggests local adaptation in starch digestion, while the same recombination mechanisms seen elsewhere generated the high-copy haplotypes.
Our ancestors' potato diet rewired their DNA. Is our modern diet causing evolution to happen even faster?
What ancient superfood gave Andean people a genetic advantage stronger than high-altitude adaptation?
How did a genetic superpower for digesting carbs become a modern-day health curse for some Indigenous groups?
Record High AMY1 Gene Copy Number in Andean Quechua Linked to 10,000 Years of Potato Farming
Overview
A 2026 study revealed that Indigenous Andean populations, especially Quechua speakers, have the highest global average of AMY1 gene copies, around 10 per diploid genome. This genetic adaptation arose over thousands of years following the domestication of the potato 6,000 to 10,000 years ago, which created strong selective pressure for efficient starch digestion. The AMY1 gene's structural instability allowed copy number variation, and individuals with more copies produced more salivary amylase, enhancing starch breakdown and providing a survival and reproductive advantage estimated at 1.24% per generation. This advantage led to the prominence of unique high-copy haplotypes in Andeans well before European contact, illustrating rapid gene-culture co-evolution driven by agriculture.