A NEW study has found that alcohol metabolism causes DNA damage that may trigger breast and liver cancers. Alcohol is known to be carcinogenic to humans in the upper aerodigestive tract, liver, colorectum, and the breast. Evidence suggests that acetaldehyde, the primary metabolite of alcohol, plays a major role in alcohol-related esophageal cancer. Now, the new study using human cells has established linkages between alcohol metabolism and acetaldehyde-DNA damage that may have implications for breast and liver cancers. Mirror When alcohol is metabolized in the human body, it is converted to acetaldehyde, a chemical that is structurally similar to formaldehyde. Acetaldehyde can cause DNA damage, trigger chromosomal abnormalities in cell culture studies, and act as an animal carcinogen. In most people, acetaldehyde is quickly converted to acetate, a relatively harmless substance, by an enzyme called aldehyde dehydrogenase 2 (ALDH2), said Philip J. Brooks, program director in the Division of Metabolism and Health Effects at the National Institute on Alcohol Abuse and Alcoholism (NIAAA). However, approximately 30 percent of East Asians are unable to metabolise alcohol to acetate due to a genetic variant in the ALDH2 gene, and have a greatly elevated risk of esophageal cancer from alcohol drinking, he explained. Mirror