This man’s face has flushed red after drinking alcohol. A harmless enough side-effect, one might think, but it’s actually a tell-tale sign of a genetic abnormality – a sign that might save his life. Up to 36% of people from East Asia experience ‘alcohol flushing’ due to a genetic mutation affecting an enzyme called aldehyde dehydrogenase-2 (ALDH2). ALDH2 is required to fully break down (metabolise) alcohol – having insufficient ALDH2 leaves the reaction incomplete, turning the alcohol to acetaldehyde, a harmful carcinogen. Alcohol drinkers deficient in ALDH2 have a vastly increased risk of developing throat cancers such as squamous cell carcinoma. For the estimated 8% of the world’s population who are ALDH2-deficient, facial flushing is a clear sign to stay off the booze, and may save thousands of lives.
Written by John Ankers
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