Adventures in Very Recent Evolution
23rd April 2011
Ten thousand years ago, people in southern China began to cultivate rice and quickly made an all-too-tempting discovery — the cereal could be fermented into alcoholic liquors. Carousing and drunkenness must have started to pose a serious threat to survival because a variant gene that protects against alcohol became almost universal among southern Chinese and spread throughout the rest of China in the wake of rice cultivation.
The variant gene rapidly degrades alcohol to a chemical that is not intoxicating but makes people flush, leaving many people of Asian descent a legacy of turning red in the face when they drink alcohol.