In Chinese and other East Asian populations, two common genetic variants (alleles) reduce alcohol tolerance and are strongly associated with lower alcohol intake because they cause an unpleasant “flushing” effect. These mutations disrupt the functioning of enzymes involved in alcohol detoxification, causing the toxic compound acetaldehyde, a Group I carcinogen, to accumulate in the blood.
The first mutation is a loss-of-function mutation in the gene for the enzyme aldehyde dehydrogenase 2 (ALDH2). The second mutation accelerates the activity of alcohol dehydrogenase 1B (ADH1B). Both are common in East Asians but rare in populations of European ancestry.
Because these alleles are distributed at birth and are independent of other lifestyle factors (such as smoking), they can be used as a proxy for alcohol intake to assess how alcohol consumption affects disease risks.
The research team used DNA samples from approximately 150,000 participants (approximately 60,000 men and 90,000 women) in the China Kadoorie Biobank study and measured the frequency of the low alcohol tolerance alleles for ALDH2 and ADH1B.
READ MORE: Cancer warning: Common UK vitamin deficiency linked to ‘five-fold’ risk
Add Comment