Ancient Amylase: The Gene that Shaped Humanity's Starch Digestion

A University at Buffalo study reveals that genes aiding in carbohydrate digestion began evolving over 800,000 years ago, even before farming. By analyzing genomes, researchers found hunter-gatherers carried multiple amylase gene copies, crucial for starch digestion, impacting human evolution and diet adaptation.

Researchers at the University at Buffalo have unveiled a groundbreaking discovery, suggesting that the genes enabling humans to digest carbohydrates may have started to evolve over 800,000 years ago, predating the advent of agriculture. This study analyzed the genomes of 68 ancient humans, including a 45,000-year-old sample from Siberia, and found pre-agricultural hunter-gatherers already possessed between four to eight copies of the amylase, or 'AMY1', gene. This gene is essential in breaking down starchy foods, such as bread and pasta.

The duplication of genes, a process where a gene replicates itself and increases in number, is seen as a critical factor in evolutionary development. The team's findings indicate that early duplication of the amylase gene prepared early humans to adapt to a diet rich in starchy foods, laying the groundwork for the genetic diversity we observe today in starch digestion capabilities.

Additionally, this evolutionary advantage was not exclusive to Homo sapiens. The study uncovered that Neanderthals and Denisovans, our close extinct relatives, also exhibited amylase gene duplications. This suggests the gene may have duplicated over 800,000 years ago, well ahead of the divergence of humans and Neanderthals. As humans began to spread and encounter diverse environments, the multiple copies of the gene provided a vital advantage for dietary adaptation, facilitating the rise of starch consumption with new lifestyle changes.

(With inputs from agencies.)