Study Shows How the Red Hair Gene Spread in Europe 4,000 Years Ago

A recent study published in Nature uncovers how the MC1R gene, associated with red hair and light skin, expanded in Europe more than 4,000 years ago. The research analyzed nearly 16,000 ancient DNA samples and over 6,000 current genomes, providing unprecedented insights into recent human genetic evolution in Europe and Central Asia.

The researchers identified that natural selection favored 479 genetic variants with high confidence, though the actual number of episodes could be much higher. This doubles previous records, which documented only a few clear instances since humans left Africa around 300,000 years ago.

Ali Akbari, the lead author, explains that for the first time, it’s possible to observe in real time how natural selection shaped human biology, from hunter-gatherers to early agricultural and urban societies. Lifestyle, diet, and community living introduced new evolutionary pressures.

These pressures sped up genetic changes affecting both health and physical traits. One notable example is the MC1R gene, linked to red hair and pale skin. Variants of this gene were positively selected in Western Europe over 4,000 years ago, likely to enhance vitamin D production in low-sunlight environments.

The team, led by David Reich and Ali Akbari, suggests that lighter pigmentation may have provided an adaptive advantage in regions with long winters and limited sunlight. However, they emphasize that the relationship between MC1R, red hair, and adaptation is complex, involving multiple genetic and environmental factors.