Which came first: the person or their addiction?
Answer: Yes, according to the latest research.
The what, why, and how of substance abuse is complicated. Ultimately, it may all come down to a combination of a person’s genes and environment.
This marriage is called epigenetics, or the study of how gene expression changes due to environmental influences, such as exposure to chemicals and even stress. These changes affect not only your health, but they can also be passed down to your children, according to the National Institute on Drug Abuse (NIDA).
In the case of substance addiction, the role of epigenetics looks something like this: A person uses cocaine, for example. This doesn’t alter the sequence of his DNA, but it may change the amount of some DNA products that are produced.
Specifically, cocaine may increase the production of proteins that correspond with drug-seeking behaviors and addiction. These changes can be permanent, making the person more susceptible to relapse.
That’s just one example of how your genes may influence addiction. In reality, there are many ways. Here’s what we know about why someone develops an addiction, what influences its development, and some ways to treat it.
1. You Can Be Predisposed to Addiction, but There’s More to the Story
It turns out there are a host of genes that determine how you react to stress. There’s also a set of genes that determine whether you’re at a higher risk of developing a substance use disorder. Together, they could be a recipe for addiction.
“This isn’t a gene for a specific trait necessarily. It’s a gene-by-environment interaction,” says Kathleen Brady, MD, PhD, vice president of research at the Medical University of South Carolina and a Genomind Scientific Advisory Board Member.
“You can be genetically predisposed but never develop a substance use disorder because you live in a protective environment,” Dr. Brady says.
“But if you have the vulnerable gene for alcohol abuse, and you experience early life trauma of some sort, there could be epigenetic changes that lead you to have an exaggerated stress response to future stress and be more vulnerable to the development of alcohol dependence.”
In other words, it’s not your genes alone or your environment alone that determines if you develop an addiction. “It’s both, which is why we call it gene-by-environment,” Dr. Brady says. “The gene does, in some ways, predispose you to handle trauma differently, but once you’re traumatized, it becomes almost like feedforward in a vicious cycle.”
Depending on which variant of the gene someone has, they’re more or less susceptible to have this interaction flip on when they encounter tremendous stress.
Early childhood trauma is one type of stressor that leaves some individuals vulnerable to the development of addictions, according to Dr. Brady.
Military service is another stressor. More than 25 percent of veterans who have post-traumatic stress disorder (PTSD) also have substance use disorder, according to the National Center for PTSD.
2. Genes Might Be Able to Predict the Severity of an Addiction
A person may experiment with tobacco, alcohol, or drugs for a variety of reasons due to their environment. But after this point of initiation, genetic factors become more involved, which may influence established patterns of use.
For instance, there are more than 400 locations on your genes and 566 variants in these locations that influence smoking or alcohol use, according to a report in Nature Genetics. Though more research needs to be done, experts believe there may be a connection between your genes and how much tobacco you use in a day, if you become a regular smoker, if you quit smoking, and similar behaviors.
In addition, 30 percent of people who use marijuana could have a cannabis use disorder, according to NIDA. Studies are starting to examine which genes may be a factor in the development of cannabis use disorder.
3. Genetic Testing May Help Inform Treatment
Genes don’t just inform the likelihood of addiction. They may also give us clues about treatment. For instance, your ability to quit smoking may be partially determined by your genetic makeup.
Treatment for substance abuse usually involves a combination of therapies, including medications. Some medications can help you manage withdrawal symptoms, such as nausea, sweating, or shaking. Other medications may reduce your cravings for certain substances. Medications can also be used to help treat underlying or coexisting conditions, such as depression or anxiety.
The challenge is people don’t react to medications in the same way, which can lead to negative side effects and may require multiple rounds of trial and error. For someone struggling with substance abuse, this can add another obstacle on the path to recovery.
Pharmacogenetic testing (PGx) is a way to help clinicians understand how your genes may affect your body’s response to certain medications. This information, along with your medical history and current health information, can help your clinician make treatment decisions for more than 260 medications.
If you or your loved one is looking for help with substance abuse, start by talking to your clinician. Ask about any tests or treatments that can help you.
Does Your Medication Work for You?
Now there is a smarter way to treat mental health conditions. Genomind’s pharmacogenetic test was designed to help your clinician personalize your treatment plan and help you avoid the painful process of trial and error. Learn more about Genomind here.