Ancient Genes Unlock Starch Secrets

Indigenous people in the Andes domesticated the potato between 6,000 and 10,000 years ago, establishing it as a dietary staple. This agricultural development led to significant genetic adaptations in these populations, which are still observable today.

New genomic research has documented these changes, particularly within Quechua-speaking descendants of the Inca Empire in Peru. These individuals exhibit a fortified version of the AMY1 gene, essential for digesting starch. On average, they possess 10 copies of this gene, which is two to four more than most people worldwide.

The study also indicates that the emergence of these genetic variations aligns with the timeline of potato domestication. Evolutionary geneticists emphasize this as a clear example of culture influencing biology, underscoring the role of dietary adaptation in human evolution.

Scientists analyzed genomic data from over 3,700 individuals across 85 populations. The findings suggest that evolutionary pressures favored increased AMY1 gene copies in ancient Andeans, potentially providing an advantage in processing starch-rich foods like potatoes. This genetic trait became more common over generations.

Potatoes were a vital calorie source in the high-altitude Andean diet and formed the core of the Inca food supply. Following the Spanish conquest in the 16th century, potatoes were introduced globally, becoming a widely appreciated food.

Peru remains a hub for potato diversity, with Quechua speakers selling numerous varieties in markets. While thousands of potato types exist in the Andean highlands, most of the world has access to only a limited selection.