DNA Test for Addiction

As the understanding of both addiction and genetics improves, the possibility of a DNA test for addiction is something that many consider very real. Just as physical traits like hair color and physical illnesses like heart disease can run in families, a family predisposition to addiction has been identified¹https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3506170/.

The difficulty, of course, boils down to the nature v. nurture argument; if someone grows up with an alcoholic parent, would it be their genes or their upbringing that leads to them becoming an alcoholic?

It’s not hard to find examples to support almost any view in a nature v. nurture debate. There are plenty of addicts from families with no history of addiction, and plenty who have never suffered an addiction despite a troubled family history. The drivers behind addiction are complicated and the research is moving towards the answer that it isn’t a result of just nature or nurture, but of nature and nurture.

Epigenetics — how the environment shapes our DNA

Epigenetics is an area of science that considers how the environment shapes our DNA, or more precisely how our DNA expresses itself. The concept is relatively simple, that although our DNA is unchanging, it can have different expressions depending on our environment. In some situations, for example, a person might produce different proportions of DNA products, such as proteins that are linked to addiction²1.K. Blum, The Benefits of Genetic Addiction Risk Score (GARSTM) Testing in Substance Use Disorder (SUD) – PMC, PubMed Central (PMC).; Retrieved September 21, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6128289/.

This can explain why some do not grow up to become addicts, but others develop an addiction later in life; they are responding as much to their environment as they are their genetic inheritance.

The complexity of genetics means we are still making discoveries. A human DNA sequence contains nearly three billion base pairs, or which 99.9% are identical in every human, but that still leaves three million potential differences and many of these will interact. So, while genes that shape physical appearance might not have an impact on addiction, those that affect your mental health and function might. Your genetic predisposition to things like stress and depression can all have an influence on whether you become addicted.

Addiction Genes

So far at least 10 genetic variations have been discovered that appear to have a direct link with addiction. Most of these are connected to dopamine-related pathways in the brain. This accords with the developing science of addiction which is focused on how the brain rewires reward pathways to cause an addiction³2.C. Pimms, Your genes and addiction – Harvard Health, Harvard Health.; Retrieved September 21, 2022, from https://www.health.harvard.edu/blog/your-genes-and-addiction-2019012815730.

Using a DNA test for addiction which looks for these genetic markers might suggest whether an individual is susceptible to addiction. However, as just 10 of the three billion base pairs in their DNA, there is still debate over exactly how much influence they have. And that’s before you even consider the almost infinite variety of environmental factors.

How Useful is a DNA Test for Addiction

If a DNA test suggested a higher risk of addiction, there are several steps an individual could take. Acknowledging the higher genetic risk, they could attempt to mitigate their predisposition by controlling the environmental factors.

Perhaps the most important step would be self-care. There is a correlation between things like poor mental health and stress and addiction. Taking extra steps to be aware of any problems and addressing them promptly can help, by, for example, avoiding temptation to self-medicate to deal with depression but, instead, seeking professional help promptly.

It might also be sensible to avoid potential addictions and situations that might contain them. This might mean avoiding social situations where there is recreational drug use or limiting alcohol intake when out.

However, some research has shown that the knowledge provided by a DNA test for addiction might not be helpful. Studies have shown that, when presented with the information, the recipients showed increased levels of negativity and feelings of loss of control.

For some, addiction moved from being an abstract possibility to something that was likely, or even certain. It’s not hard to see how a such a sense of fatalism might lead to addictions that would not have happened if they had remained ignorant.

Alternatives to DNA Tests for Addiction

There are many factors that can warn of a higher predisposition to addiction without taking a DNA test. The most obvious is a family history of addiction, and those with such a history may want to take care with addictive substances and behaviors. This might mean abstinence or questioning motives when partaking in an addictive activity.

Mental health can also indicate a risk of addiction. It is not clear if this is because of a link between mental health and addiction or simply because poor mental health might result in addictive behaviors as a form of self-medication. Again, it is useful for anyone experiencing mental health problems to remain mindful of the reasons and motives behind any potentially addictive actives they undertake.

Finally, there are some physical clues in the science of addiction. The body’s ability to metabolize drugs will impact on behavior. East Asians, for example, are generally slower at processing alcohol, resulting in worse after-effects and, in turn, reducing the prevalence of alcohol abuse. Not suffering from hangovers, or negative effects from any drug, might be a sign to limit intake, rather than to enjoy to excess.

Future for DNA Testing & Addiction

It’s hard to conclude there is currently any value in DNA testing for addiction. There are simply too many other genes and factors for the results to be meaningful. Indeed, the evidence suggests that the psychological effect on behavior can far outweigh the benefits the knowledge brings. Instead, it is better to act on information more readily available, like family history and environment.

However, as science progresses it is likely a more meaningful test will, eventually, exist. Perhaps the first place it will be used and useful is to help inform medical treatment. A better understanding of an individual’s predisposition to addiction could help determine medical treatment, widening or narrowing medication options appropriately.

DNA tests for addiction are not quite ready for widespread use. And even as they improve, they will only ever be able to indicate a predisposition and not predict the future. For most people all the information they need will come from what they already know about their family and from their own experience.

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