ScienceDaily (2010-12-27) — Scientists have found that a genetic variant of a brain receptor molecule may contribute to violently impulsive behavior when people who carry it are under the influence of alcohol.
The researchers sequenced DNA of the impulsive subjects and compared those sequences with DNA from an equal number of non-impulsive Finnish control subjects. They found that a single DNA change that blocks a gene known as HTR2B was predictive of highly impulsive behavior. HTR2B encodes one type of serotonin receptor in the brain. Serotonin is a neurotransmitter known to influence many behaviors, including impulsivity.
http://www.sciencedaily.com/releases/2010/12/101222131121.htm