|MadSci Network: Medicine|
Twin and adoption studies provide the evidence for a genetic predisposition to alcoholism. Part of this may be related to alcohol sensitivity due to a loss of enzyme that helps with the breakdown of acetaldehyde. When this is absent or reduced there are unpleasant side effects when alcohol is consumed (flushing). Another possible genetic factor that is being considered now is focused on a neurotransmitter or "brain substance" called serotonin - with some alcoholics there is a decrease in transmission. But there are many other factors not related to genetics. The good news is there is some increase in risk of developing alcoholism, but that doesn't mean you will definitely become an alcoholic.
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