We know that addiction is a disease. But, have you ever wondered why some people are seemingly prone to addiction while others are not? If you’ve ever given any thought to the matter, you are likely to have touched on a related question: Is addiction a hereditary disease? If you are someone with a family member struggling with addiction, especially if you are a child of an addict, the question is particularly important. Naturally, you might worry about your own likelihood of becoming addicted.
The truth is, addiction is a very complex, multidimensional disorder. The exact circumstances vary from person to person. To better understand this, we need to look at all the variables of the disease. By doing so, we can go a long way towards clarifying the origins of addiction, which may help destigmatize it and lead to more timely treatment. With that in mind, let’s take a look at addiction from a hereditary perspective.
Is addiction a hereditary disease?
The short answer is yes; but as we will see, addiction is more complicated than that. It is a complex disease that is, to some extent, tied together by shared genetic and environmental etiological factors. Though evidence suggests an undeniable connection between genetics and addiction, hereditary traits are just one half of the equation. Therefore, in the context of the age-old “nature vs. nurture” debate: genetic predispositions are looked at along with environmental influences to properly evaluate addiction. Put simply, the interaction of one’s genes, life experiences, and environment all influence a person’s behavior and health.
Addiction is a hereditary disease
So, what has the research on the genetics of addiction revealed? Is addiction a hereditary disease? Well, once again, the short answer is yes. A wide variety of biological processes do indeed influence the risk of addiction.
According to the American Psychological Association (APA) at least half of a person’s “susceptibility to drug or alcohol addiction can be linked to genetic factors.” Likewise, the National Institutes of Health (NIH) estimates that roughly 40–60 percent of an individual’s vulnerability to substance use disorders is attributable to genetics.
- Tobacco: Genetics account for roughly 75 percent of a person’s proclivity to take up smoking
- Alcohol: The National Institute for Drug Abuse estimated that up to 50 percent of a person’s susceptibility towards addiction is linked to genetics.
To better understand how researchers came to the above conclusions, it’s worth briefly digging into the science behind genetic testing.
A vital avenue of research for scientists is attempting to answer why some people are uniquely vulnerable to addiction. Recently, progress has been made in understanding the genetic epidemiology of addiction, particularly substance abuse problems. You may or may not have heard of the term “addiction genes”. When scientists assess for “addiction genes,” what they are looking for are biological dissimilarities that might render a person more or less vulnerable to addiction.
Case Study: Substance Use Disorders
With that in mind, let’s focus on substance use disorders. These disorders have been known to disproportionately affect certain families. So, when examining the genetic architecture of substance use disorders, scientists place special emphasis on family histories. DNA sequences of family members are compared in order to distinguish those genes connected with addiction. To best analyze patterns of inheritance, researchers compartmentalize the family into two groups: affected and unaffected.
Afterwards, researchers evaluate “for segments of chromosomes that are more common in affected people compared to unaffected. They narrow the segments down to specific genes to study further”. Essentially, by looking at members of the same family, they can find the genetic differences that are shared by those who experience addiction.
Propensity Isn’t Destiny
It’s important to keep in mind that a genetic predisposition does not guarantee that someone will develop addiction, or even patterns of abuse. It simply means that their risk factor is affected by their genetic makeup. As the APA notes: “propensity isn’t destiny”. In other words, no single gene determines unequivocally whether a person will inherit addiction.
So, we’ve answered the question: Is addiction a hereditary disease? But as stated above, genetics are only one piece of the puzzle. Let’s look at some other factors that may lead to addiction.
As we’ve seen, your family background can play a significant part in determining your likelihood to become addicted via your genetics. But, while we inherit our genetics from our family, they also make up a big part of our home environment.
A person’s early childhood interactions can play a pivotal role in determining one’s risk for addiction. For example, a child of an addict is more likely to experience heightened behavioral problems, which may lead to experimentation with addictive substances. Likewise, research suggests children and adolescents who have experienced traumatic events are at a greater risk of adopting a substance abuse problem. Moving outside the family environment, a person’s community and friend groups also play a central role in a person’s pathway to addiction.
So, let’s recap. We’ve established that addiction is a hereditary disease. There is an undeniable connection between certain inherited genes and a higher risk of addiction. However, that is not the whole story. Your home, school, and community environment all play a significant part in defining your addiction risk. To say addiction is not a hereditary disease would be wrong, but it would also be incorrect to say that is all it is.
Rather, addiction is shaped by a confluence of factors, whether it be genetics, environmental exposures, or experience with trauma. All of these pieces come together to form the complicated puzzle that is addiction. Even then, you may have someone who meets all the criteria and manages to live free of addiction. A greater risk of addiction is never a foregone conclusion. So, is it nature or is it nurture? In the case of addiction, it’s undoubtedly both.