Male Impulsivity and Addiction Linked to One Gene
Years ago a comedian was known for his punch-line "the devil made me do it". Current research into the links between genetics and undesirable or impulsive behavior may give rise to a new culprit: "my genes made me do it." Researchers have built on previous studies in pinpointing the genetic area associated with certain behaviors such as addiction and impulsivity but hasten to point out that a person is more than a single gene.
The study, conducted through the University of Nebraska, involved 439 Caucasian collegiate volunteers. The group was all-white in order to control for any genetic differences that would be racially based. Study volunteers agreed to a cheek swab donation of genetic material. They were then asked to perform a task specifically created to gauge a person’s patience as opposed to impulsivity. Lastly, the group completed a questionnaire that asked for information concerning not only personality traits but also their personal use of substances like tobacco, alcohol and other drugs.
The study confirmed prior findings which demonstrate a definite link between behavior and DNA. Previous studies had identified a particular segment of DNA, known as NRXN3, and found links to problems of obesity, nicotine addiction, alcohol dependency and opiate addiction. The NRXN3 gene is responsible for connections among brain cells. Variations of the gene impact whether or not the human brain gets much or little of the protein which controls impulsivity. Therefore, underneath all of the linkages between the gene and addictive behaviors, lies a core influence on impulsivity. The University of Nebraska study found that in men, variations of that DNA segment make men two and a half times more likely to experience addiction problems such as alcoholism.
It remains unclear why the gene variations affect men and not women. The fact that gender plays a role in the findings points to the complexity of behavioral genetic study. The associations between genetics and behavior are complicated at best. The NRXN3 gene is one of many gene mutations which may be connected to certain behaviors. Other gene variations have been shown to influence promiscuity, violence, impulsivity and aggression – even a preference for horror movies. So while the NRXN3 gene may create an elevated risk for certain impulsive behaviors, there are a multiplicity of factors which influence a man’s behavior.
Understanding that a connection exists is helpful, but remains a far cry from understanding all that the relationship entails. The University of Nebraska study underlines the influence of NRXN3 on addiction and impulsivity in men while leaving many questions unanswered. Why, for example, is one variation of the gene related to impulsive behavior while another seems connected to alcohol addiction and another to aggression? What is certain is that genes alone are not deterministic. A personality is a compilation of environment along with a host of genetic influences. In other words, a single gene mutation is not a pass on bad behavior.
