Your genes and addiction

Over the last decade, the prevalence of opioid addiction has increased to epidemic levels, but unfortunately therapeutic interventions for the treatment of addiction remain limited. We need to better understand the triggers for the development of addiction in order to develop more targeted prevention and treatments. One of the key questions that researchers in the field of neuropsychiatry are trying to answer is why some people are more vulnerable to addiction. As in most cases of psychiatric disorders, genetic and environmental factors interact to determine how vulnerable, or likely, you are to developing a substance use disorder.

Drugs of abuse, including opioids, act on the brain’s reward system, a system that transfers signals primarily via a molecule (neurotransmitter) called dopamine. The function of this system is affected by genetic and environmental factors. For example, a recent study published in the scientific journal PNAS revealed one of those genetic factors. Researchers demonstrated that a type of small infectious agent (a type of RNA virus called human endogenous retrovirus-K HML-2, or HK2) integrates within a gene that regulates activity of dopamine. This integration is more frequently found in people with substance use disorders, and is associated with drug addiction.

How does stress induce epigenetic changes?

Accumulating evidence suggests that environmental factors, such as stress, induce epigenetic changes that can trigger the development of psychiatric disorders and drug addiction. Epigenetic changes refer to regulations of gene expression that do not involve alterations in the sequence of the genetic material (DNA) itself. Practically, epigenetic changes are information that is added on to already existing genetic material, but can affect the expression of genes.

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.

Stress reduction can help reduce the risk of developing an addiction and prevent relapse

Fortunately, the negative effects of stress can be alleviated by other factors, such as physical activity or social support. These behaviors produce epigenetic changes that prevent the development of addiction and can have a beneficial role in treatment when used in combination with other interventions, such as cognitive behavioral therapy and, for some people, medications. One of the ways that physical activity could be effective is by reducing negative feelings, including stress and the accompanied stress-induced epigenetic changes. In the example of a stressful situation such as the death of a significant other or loss of a job, if a person engages in physical activity this can reduce their stress-induced epigenetic changes, which will decrease the risk of developing addiction or stress-induced relapse.

Hope for targeted addiction treatments

We now know that the function and dysfunction of the brain’s reward system is complicated, plastic (undergoes changes based on negative and positive factors), and involves complex interactions of genetic and environmental factors. Alterations in gene expression can lead to changes in the function of the brain’s reward system, so a person is more or less likely to self-administer drugs. Together this knowledge can ultimately lead to the development of multilevel and more efficient prevention and therapeutic approaches to address the ongoing opioid epidemic.

Resources

Human Endogenous Retrovirus-K HML-2 integration within RASGRF2 is associated with intravenous drug abuse and modulates transcription in a cell-line model. Proceedings of the National Academy of Sciences, September 24, 2018.

Comments:

  1. Bob Linke, CEO, Embera NeuroTherapeutics

    Maria,

    Thanks for your article discussing the role stress plays in addiction and relapse. While impact of stress in addiction has been widely studied in the scientific literature, it is not generally understood by the public at large. Treatments that could reduce the physiologic effects of stress may be effective treatments for addiction by helping those suffering an addiction to maintain long-term abstinence even when faced with stressors. Our company, Embera NeuroTherapeutics, is one of the few working to develop new treatments for patients and the clinicians treating this disease with a focus on addressing the stress response system and its role in addiction. We have two products that are entering mid-stage clinical testing one for cocaine addiction and a second for smokers to help them quit their nicotine addiction.
    Thanks for your help raising the awareness the addiction problem we face in our society and your continued work to advance the science in a field in need of better treatments for patients.

  2. Meena Chintapalli, MD. FAAP

    I mentioned this in both my books” Brain, Mind, SAI Educare “ – published in 2004 and
    “ Early Brain Sprouts from States to Traits”
    A clear , universally applicable Cognitive Behavior Management was discussed and gave a table for quick referenced
    ICIHS congress sponsored by NIH in October of 2003 introduced speakers who proved genetic transcription changes from exposure to calming music and hymns as an anti stress factor. Hindu Vedic philosophy taught this through YOGA practice techniques breathing exercises, meditation and Hatha Yoga techniques.
    Now AIIMS proved with 26 years of prospective brain research that Gayatri Mantra chanting increased conscience, attention span, reflective thinking, self- regulation , decreased impulsivity and instant gratification.
    Thank you SCIENCE for reaching and meeting SPIRITUALITY to make us understand the difference between Human Being to be a Human
    Meena Chintapalli, MD. FAAP

  3. Jason

    Cigarettes are absolutely an addiction which is why I read these kind of articles. I smoked 10-15 per day for 30 years and 5-10 for the last 8. I quit for 3 different health events in the last 10 years for 4-6 months and went back to it. I exercise and control my weight but for someone with my genes that’s not enough. I’m having triple bypass surgery on Wednesday. I quit 2+ weeks ago when I got the diagnosis. Doctor says I should be fine. I hope I don’t start smoking again but even this surgery doesn’t make that certain. The very definition of addiction.

  4. Patricia

    What about consumption of certain foods as a stressor? For example, consuming foods that aggravate arthritis due to its inflammatory nature like the Solonaceae or nightshades (peppers, potatoes, tomatoes, eggplant) which are known as rheumatism enhancers. These should be avoided instead of reaching for painkillers after its consumption. Perhaps if we study more the connection between nutrition and pain we can have a deeper understanding of addiction in our system.

  5. a goldstein

    Just as stress can induce negative epigenetic changes, I suspect that activities like meditation and yoga induce positive epigenetic changes. I am encouraged to read that more and more pre-college schools are offering mindfulness classes. Practicing mindfulness with meditation is a life enhancing activity and shows how you can improve your self awareness. You just need to get good information and to keep at it.

    • Sam

      I have had huge befits through daily listening to many meditation video on youTube. Some are very powerful based on their affects on certain frequencies and their affects in certain areas of the brain. Just learning and it’s helping with my headaches and sleep. I would love to find once designed for withdrawal, so it could help my friend with her tapering off opioids.
      We forget how power our brain is and just live on autopilot.

  6. Christina

    stressful situation, such as the death of a significant other or the loss of a job

    Edit: Stressful situation such as; death of a loved one, divorce, loss of a job, moving etc…

  7. Oscar

    My spouse suffers from delusional jealousy. You make reference to stress as a factor in addiction. Can this also be a factor in delusion? Is treatment similar to that for addiction?

    • Patricia

      Oscar, your wife is suffering from extreme insecurity. She is having a spiritual crisis regarding her own creativity. Delusions mean she is highly sensitive and very creative. Maybe working with arts and crafts, dance or playing music can help her insecurity.

  8. David

    When saying that it is “the choices that we make”, you infer that typical response that addicts have heard for decades, even centuries, that you are just a weak willed person making the wrong decisions! Yet time has shown over and over, that many very strong-willed people, who have started and run very successful companies, who have very good families, who have worked very hard and are disciplined in every area of their life, have shown exemplary strong wills except when it comes to alcohol or drug addiction. Science is now finding that there are genetic and other complicated reasons for addiction to take place. your judging of their very character shows a lack of understanding and a judgmental attitude. I myself am a church pastor and have a very strong reputation in my community in upstate NY, yet I attend AA meetings 3 times/week to remain sober because of my genetic inclination to fall in the alcohol trap.

  9. R.T. Neary

    Attitude is vital and can be positively conditioned, starting with the development of a true purpose for our lives. In turn, the hormonal balance is affected and physical health emerges.

  10. Peter

    “never lead me to addiction.”

    “My only vice is smoking cigarettes”

    OK……

  11. Georgina Williams

    Found this information very interesting for my dissertation on drug addiction and relapse.
    Thankyou

  12. Nancy

    I agree that if you have loss or stress being active helps. But addiction depends on not only personalities as an individual, but also the choices you make as an adult. I have had several losses without being active when I should have been, but it never lead me to addiction. My only vice is smoking cigarettes and 1 coffee in the morning. I’m not over/under weight, rich, or on assistance from the government, or have had a glamorous life. It is the choices we make!

    • Frances Low

      Cigarettes. What a bad “choice”!

    • Susan

      So sorry for your losses, Nancy. However, you may want to examine your statement re. not being addicted to anything, but following it up by rating your “vice” of smoking cigarettes. That, in itself, may very well be your personal addiction. If you only smoked a cigarette, say— 12 times a year, it may be relate differently. But I suspect the cigarette is what you go for when you are under stress. Forgive me if I am wrong.

    • Monteze Snyder

      You may be grateful that you did not acquire the genetic predisposition noted in the article; tmany other have.

    • Marc

      Nancy, the concept that only the choices you make does not necessarily apply in his case. This study was that your brain reacts to stress or other stimuli that can cause it to seek out a “reward” more often or a craving for such a reward. You can decide to not do opium in any case, but people do opium anyway. As such research along these lines could help find a way to reverse said changes could be great for the medical field and rehab.

    • Adrienne Okin

      Last I heard smoking cigarettes indicates an addiction to nicotine one of the most additive substances in the entire world which is responsible for aprox 300,000 deaths a year. Adrienne

    • Aurora

      Smoking IS an addiction and coping mechanism. It acts on the brain in the same way opioids do. It was my drug of choice for 25 years. Now 30 years clean.

      • Peggy

        I totally agree. Smoking is certainly a bad addiction. Been there done that. Glad to be free of it for 32 years now. Was the hardest for me to kick even over drugs & alcohol. God is a great healer. You have to want his help.

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