Most of us are guilty of having snuck a beer or two in our best friend’s basement during high school. But some teens take this to the limit and engage in extremely risky behavior like binge drinking and illicit drug use. Although certain environmental factors, such as where children live and what kind of household they grow up in, can have an affect on their likeliness to act out, a new study may have also identified a genetic aspect of impulsivity.

For the study, now published online in the open-access journal Frontiers in Genetics, researchers from the University of Sussex in England used mice to link impulsive behavior to certain genes. Under controlled conditions, the mice were assessed for their ability to wait to obtain a reward, and then scored on their scale of “impulsivity.” The team then correlated the impulsive rating into a mouse genomic database to find specific genes responsible for the behavior.

After identifying the mouse gene linked to impulsivity, the researchers looked for the human equivalent of the mouse gene. Then, they observed 423 teenagers (average age 14) who had this human impulsivity gene. The teens were asked to answer a questionnaire on their drinking and drug use habits during the previous month. Just as the mice, the teen participants were also evaluated for their ability to wait to obtain a reward and underwent an fMRI while these tests were conducted.

Results from both the mouse and human studies showed one gene, KALRN, to be associated with impulsivity and the tendency to binge drink in adolescence. This gene contains a protein called kalirin, which is essential for the development of the nervous systems, especially the formation of nerves associated with impulsivity related disorders such as ADHD. Although past research has found a genetic component to substance abuse, this is the first to find a gene responsible for impulsive behavior.

“Our findings are important because we show that certain variations in the KALRN gene are associated both with alcohol binge drinking and with brain activation during impulsive responding in adolescents," said lead researcher Dr. Yolanda Peña-Oliver in a recent statement.  

According to Peña-Oliver, these results will hopefully provide insight into discovering biomarkers for impulsivity and alcohol abuse. This could be used to predict which individuals may be most vulnerable to conditions such as ADHD and drug addiction, and could serve as a pathway for early intervention.

A 2015 study published in the journal Neurobiology of Diseases found that binge drinking is especially worrisome in teens because it can not only lead to brain changes but also increases the likelihood teens will develop substance abuse problems as an adult. Seeing as a recent Centers for Disease Control and Prevention report found that 21 percent of high school students admitted to binge drinking, a way to identify those most at risk could have important implications.

Source: Peña-Oliver Y, Carvalho FM, Sanchez-Roige S, et al. Mouse and Human Genetic Analyses Associate Kalirin with Ventral Striatal Activation during Impulsivity and with Alcohol Misuse. Frontiers in Genetics. 2016