A new study suggests that a variation in a gene called GABRA2 increases the risk for alcoholism. HealthDay reports that people with this genetic variation tend to act impulsively when they are under stress, which can lead to problem drinking.

The study, published in Molecular Psychiatry, included 449 people from 173 families. In 129 of the families, at least one member had been diagnosed with alcohol dependence or abuse. The researchers used brain scans to track blood flow in the brains of 44 young adults from these families as they expected to win or lose money. The scans showed that people with a particular form of the GABRA2 gene that is linked to alcoholism had greatly increased levels of activity when the young people were anticipating winning or losing. The increased activity took place in an area of the brain called the insula, which has previously been linked with addictive behavior.

The researchers said that it is important to note that genetic risk factors are not the only factor in determining whether a person develops alcoholism.