The Relationship Between Genetics and Addiction

Several factors can impact the development of addiction and researchers believe that genes account for around half a person’s risk for addiction.¹ Other factors such as environment may also play a contributing role to developing an addiction.¹

If you have a family history of addiction, or if you or a loved one are dealing with substance misuse, you may be wondering if the theory of addiction and genes could impact your own family and what to do about it.

This article will cover what you need to know about addiction and genes and what treatment options are available if you or a loved one are struggling.

What Are Genetics?

Genetics refers to the study of genes, which contain the information about which traits will be passed from parents to children.^{1, 3} Genes are heritable structures made up of different DNA arrangements on chromosomes.² People have about 20,000 genes on their chromosomes.³ Genetic variations can play a role in the individual traits a person has.

Certain diseases, like sickle cell anemia, can be caused by mutations, or changes in the DNA sequence. Mutations can occur because of factors like copying errors during cell division, exposure to substances, or infection by viruses.^{1, 6}

Other diseases are the result of epigenetic changes, or changes in gene expression that are not caused by alterations in DNA sequence, but by environmental factors.¹ Certain lifestyle choices or environmental factors may actually “mark” DNA structures and lead to new cell types.¹ These changes may then be passed down to children.^{1, 4}

Is Addiction Genetic?

There is evidence of the connection between genes and addiction, and gene variation can contribute to a person being at higher risk for addiction.¹ According to the National Institute on Drug Abuse (NIDA), family studies involving identical twins, fraternal twins, adoptees, and siblings have suggested that genes are one of the potential causes of addiction to alcohol, nicotine, and other substances.¹

Genes are only part of the story, however; most diseases, including addiction, are believed to be the result of a combination of factors, including different genes, environmental, and lifestyle influences.⁵ It’s important to remember that a person’s DNA does not mean a certain disease or addiction will happen because lifestyle choices also play a role in how the human genome works.⁵

Addiction, also known as substance use disorder (SUD), is a complex brain condition characterized by compulsive substance use despite the negative consequences.⁷ Addiction is considered a brain disorder because of functional changes to areas in the brain due to repeated substance use. Areas of the brain that can be affected are those that govern stress, reward, and self-control.^{7, 8}

Genes are believed to account for around 40% to 60% of a person’s risk of addiction.⁹ Genetic risk also includes the impact of environmental factors (like trauma or parental drug use) on gene function and expression.⁹

It’s important to remember that SUDs are affected by changes in multiple genes; there isn’t just one “addiction” gene or genetic change that is responsible for addiction.¹⁰ Even if you have a genetic predisposition to addiction, you first need to use the substance—and then repeatedly use it—for addiction to occur.¹¹

Role of Genes in Specific Addictions

Researchers have studied many different genes in animal models, usually mice, and in families to examine the potential link between genes and addiction to drugs or alcohol.^{1, 10} Mice are often used because they share many similarities in genetic structure and reward pathway with humans.¹⁰

While the research is far from complete, scientists have found certain links between drug addiction and genes and genetic associations, which may increase a person’s risk of certain types of addictions.¹⁰

Genes and Alcohol Addiction

There is no specific “alcoholism” gene and many factors play a role in the development of alcohol addiction, or alcohol use disorder (AUD).¹²  However, scientists have found different links between genes and alcohol addiction that could explain why some people develop AUD and others don’t.¹²

For example, one NIDA-funded study examined a comprehensive database of around 1.2 million people to examine the link between substance use behaviors and genetics, specifically examining nicotine and alcohol use.^{1, 13}

They found that 400 locations in the genome (genetic information of a person) and a minimum of 566 variants within these locations play a role in nicotine or alcohol use.¹³ These genome locations are believed to influence functions of different chemicals, including dopamine (the brain’s reward chemical), which play a role in addiction.¹³

A person’s risk of AUD can be significantly higher if they have a first-degree relative with AUD, meaning parents or siblings. Research has also found a link between second-degree relatives (i.e., aunts, uncles, and grandparents) and even third-degree relatives (i.e., cousins, great-aunts, or great-uncles).^{15, 16}

Genes and Cocaine Addiction

The risk of cocaine addiction is highly correlated with a person’s genes. Cocaine addiction is thought to have an estimated heritability (rate of being passed down) of 65% to 79%.¹⁸ Multiple genes are thought to play a role in cocaine addiction.¹⁹

How to Help Prevent Alcohol or Drug Addiction

Addiction may have a genetic component, but it is also a preventable and treatable disease. Early intervention and prevention programs can help mitigate the risk of addiction in young people.²¹

The following methods may be helpful at reducing and/or preventing substance use, especially in younger people:²²

• Providing accurate and non-stigmatizing information about addiction and mental health disorders.
• Providing education about prevention.
• Presenting alternatives to substance use, such as fun or meaningful activities and hobbies.
• Implementing strategies to encourage policy changes that impact social and home environments.
• Improving and increasing the availability of resources for preventing substance misuse in communities.
• Identifying problems early on and increasing access to referrals for addiction and mental health services.

Treatment for Addiction

If you or someone you care about are struggling with addiction, there are various types of treatment that can help. Your recovery program may include one or more of the following treatment options:^{23, 24}

• Detox. This is often the first step in the recovery process. It helps people stop using substances and keeps them safe and comfortable as they undergo withdrawal in a medically supervised environment.
• Inpatient treatment or Residential rehabs. These can be standard, luxury, or executive programs, which require that you live at the facility for the duration of treatment while receiving care. Services may include behavioral therapy, medication management, 12-step support groups, aftercare planning, and more depending on your level of care.
• Outpatient treatment: Outpatient programs provide the freedom to live at home and fulfill home, school, or work responsibilities while receiving treatment, such as therapy or counseling.
• Dual diagnosis: A dual diagnosis (or co-occurring disorder) means a person suffers from an addiction and a physical or mental health condition, such as depression, post-traumatic stress disorder (PTSD), diabetes, or hypertension. If you suspect or know that you have a dual diagnosis, it may be beneficial to seek a rehab program that is experienced in treating co-occurring conditions.
• Behavioral therapy: A credentialed therapist will use several therapeutic techniques to help you change thoughts, feelings, and behaviors that can lead to addiction and help you develop coping skills so you can prevent relapse. Therapy can take place one-on-one and in groups.
• 12-step programs: 12-step programs, such as Narcotics Anonymous (NA) or Alcoholics Anonymous (AA), provide members with encouragement, support, and guidance while working toward achieving and maintaining a sober and healthy life.

If you have a family history of substance misuse, it’s valid to feel concerned about the impact of genes and addiction on yourself or a loved one. If you or someone you know is struggling with addiction, call to speak to our compassionate admissions navigators about treatment options, to check your insurance coverage at American Addiction Centers’ facilities, and ask any questions about addiction treatment.