Addiction can be inherited from family members, research shows.
A new Rutgers study suggests there is a correlation between genetics and addiction, and specifically, people who have a high sensation-seeking personality trait may be more likely to develop a cocaine addiction. These findings were published in the journal Neuropharmacology and offer insight into the genetic factors that can lead to addiction to substances when triggered by certain environmental conditions. The findings offer support for ways to properly treat addiction.
“Although many people try illicit drugs like cocaine or heroin, only a small proportion develop an addiction,” said lead author Morgan James, a member of the Rutgers Brain Health Institute and an assistant professor in the department of psychiatry at Rutgers Robert Wood Johnson Medical School. “The interaction found between sensation-seeking traits and the drug-taking experience show that predisposition to addiction has a genetic basis, and that this interacts with environmental factors such as patterns of drug use. The sensation-seeking trait was predictive of rats’ likelihood to exhibit stronger motivation for drugs when we gave them the opportunity to take cocaine.”
A previous study published in the Journal of Clinical Pharmacology & Therapeutics defines addictions as “chronic relapsing psychiatric disorders characterized by the compulsive and dyscontrolled use of a drug or activity, with maladaptive and destructive outcomes.” Addictions don’t always involve the use of drugs and alcohol, but rather, can include other impulsive behaviors such as excessive shopping, gambling, and internet use. That same study suggests, “Family, adoption, and twin studies reveal that an individual’s risk tends to be proportional to the degree of genetic relationship to an addicted relative. Heritabilities of addictive disorders range from 0.39 for hallucinogens to 0.72 for cocaine.”
In a lab study to test the current hypothesis, rats who demonstrated a high sensation-seeking personality with a desire for new, stimulating experiences and a willingness to be more risk-taking than others were more apt to develop behaviors similar to that of human addiction. In other words, rats that were predisposed with these genetic traits showed a greater risk of losing control much the same as humans with risk-taking traits might lose control over their drug intake.
For instance, if a person is genetically predisposed to addiction, according to Harvard University, “A stressful situation, such as the death of a significant other or the loss of a job, triggers the release of steroid hormones called glucocorticoids. Those stress hormones trigger alterations in many systems throughout the body, induce epigenetic changes, and regulate the expression of other genes in the brain. One of the systems that is affected by stress hormones is the brain’s reward circuitry. The interaction between stress hormones and the reward system can trigger the development of addiction, as well as a stress-induced relapse in drug or alcohol recovery.”
A major goal of addiction research has been to identify factors which predict vulnerability. Future studies can build on this to determine what is different in the brain chemistry of those who are highly sensation-seeking.