A new study has shown how variation in the gene RASGRF-2 makes teenagers more prone to binge drinking. Researchers from King's College explain how this variation makes structural changes in the brain and how this in turn leads teens to become heavy drinkers later in life.

Previous research has shown that alcohol and other additive substances activate the dopamine system in the brain which makes people want to drink more alcohol. However, not all people become binge drinkers. The reason, researchers have said, is because a gene variation makes people more prone to binge drink. The current research conducted on teens explains how the variation in the gene drives people to binge drink.

"People seek out situations which fulfill their sense of reward and make them happy, so if your brain is wired to find alcohol rewarding, you will seek it out. We now understand the chain of action: how our genes shape this function in our brains and how that, in turn, leads to human behavior," said Gunter Schumann, from King's IoP and lead author of the study.

The study included 633 boys who had been exposed to significant amounts of alcohol by age 14. Researchers analyzed their brain scans and found that boys with certain variations in the RASGRF2 gene had higher activation of the ventral striatum area of the brain. The study results showed that brains of people who had variation in the gene released more dopamine when anticipating a reward. This is why these people drink more alcohol.

"We found that the RASGRF-2 gene plays a crucial role in controlling how alcohol stimulates the brain to release dopamine, and hence trigger the feeling of reward. So, if people have a genetic variation of the RASGRF-2 gene, alcohol gives them a stronger sense of reward, making them more likely to be heavy drinkers," said Schumann in a news release.

Researchers confirmed their findings by re-analyzing the brains of these boys at 16 years of age. They found that boys with the gene variation were more likely to be frequent drinkers than boys who didn't have the genetic variation.

Researchers say that knowing certain teens may be at high risk of developing a full-blown addiction may design intervention strategies that target this vulnerable group.

Previous research published in the Journal of School Health has suggested that teens that binge drink are more likely to abuse other drugs than teens who use marijuana.

In the U.S., people aged 12 to 20 years drink 11% of all alcohol consumed in the country and about 90 percent of this alcohol is drunk during a binge drinking sessions, says Centers for Disease Control and Prevention.

The study is published in the journal Proceedings of the National Academy of Sciences.