Genetic Study of Impulsiveness Reveals Associations with Drug Use

Some of the same genes that influence a person’s propensity toward impulsiveness also affect whether or not he or she will use drugs, according to a new study led by researchers at the University of California, San Diego School of Medicine.

Published today in the Journal of Neuroscience, the study is another in a series of studies done by researchers looking at the genetic underpinnings of behavior, addiction, and psychological disorders. For this work the scientists used data from more than 20,000 23andMe customers who consented to participate in research, making it the largest genetic study of impulsive behavior to date.

Behavior

“By studying the genetic basis of normal variation in behavior, we can learn about the role of genetics in complex psychiatric disorders like drug abuse,” said lead author of the study Abraham Palmer, Ph.D., a professor of psychiatry and vice chair for basic research at the University of California, San Diego School of Medicine. “Additional studies of younger and more diverse populations could provide additional insights into the genetics and consequences of impulsiveness.”

Prof. Abraham Palmer

For this work, and a study Palmer and his team did last year that also looked at another measure of impulsivity called “delay discounting,” the researchers compared genetic data with survey responses on impulsivity and a history of drug use from 23andMe customers who consented to participate in research. The genome-wide association study found variants in the gene CADM2 — previously implicated in risk-taking, alcohol consumption, and cannabis use — associated with impulsivity and drug use. The team also identified an association with a variant in a gene previously implicated in schizophrenia risk — CACNA1I. They also saw an association with something called “negative urgency”— a tendency to act impulsively in the face of adversity.

Big Data

These findings demonstrate how an individual’s genetic makeup may predispose them to engage in risky behavior, including drug use and abuse. Additional studies of younger and more diverse populations could provide further insights into the genetics and consequences of impulsive personality traits, the researchers said.

The study also shows the potential of large datasets like 23andMe.

“Data shared by 23andMe research participants helped make this work possible — and this is one of several recent publications we’ve worked on related to personality, behavior and psychiatric conditions,” said Sarah Elson, PhD, Senior Scientist, 23andMe.

“These findings may have potentially significant effects on how we interpret the relationships between genetics and mental health; and, in the future, predict and treat some of these hard-to-understand conditions.”