I’m sorry that I have to use an almost clichéd literary trick to explain this. First, let’s explain why not to use genetic testing.
If you believe addiction is caused by a weak will, a spiritual emptiness or a moral problem, there’s really no point in doing genetic testing. But on the other hand, there’d also be no reason for doing addiction treatment. Spiritual guidance is free and freely available to all. The law of the land should promote good behavior and lead people willing to change to the great number of spiritual teachers around, so there’s no reason to spend money on addiction treatment. Just keep up the war on drugs, and this will all sort itself out. The insurance companies love this explanation.
On the other hand, if you believe that drugs are the only cause for addiction, there’s really no point in doing genetic testing. Under that assumption we’re all the same, and, through bad decisions or poor social policy, some of us will get exposed to addictive drugs, which change our brains and cause addiction. But on the other hand, if drugs were THE cause of addiction, we’d have no explanation for compulsive gambling, compulsive overeating, sex addiction, etc. We’d have to limit our understanding of the problem of addiction to drugs, and as that focused understanding has not led to a solution for the last 100 years, we’d have to wonder if it’s the correct understanding. Again, we would need to focus on the war on drugs, prevent addiction by preventing exposure to drugs, and keep people with addiction drug free until their brains go back to normal. If you believe that, the answer to addiction lies not in medical or psychological treatment, but in living in a monastery for about 3 years, free of charge. The insurance companies love this explanation too.
Now if you don’t believe that addiction is a moral problem and you don’t believe it’s caused by drugs, then you’re left with a real conundrum. What the hell causes addiction? Well to answer that we’d have to first define what addiction is.
The American Society of Addiction Medicine has published a definition of addiction, which can be summarized in its short form:
Addiction is a primary, chronic disease of brain reward, motivation, memory and related circuitry. Dysfunction in these circuits leads to characteristic biological, psychological, social and spiritual manifestations. This is reflected in an individual pathologically pursuing reward and/or relief by substance use and other behaviors.
Notice that addiction isn’t limited to drugs, and that the illness comes first; it causes symptoms; and it’s the symptoms that cause the characteristic behaviors we associate with addiction. That leaves us wondering what causes addiction? Could it be the person’s genetics?
It’s long been known that addiction runs in families, but many answer that with the observation that we learn our morals and our behaviors in our family as well. That’s true, but Swedish adoption studies have shown that the male sons of alcoholic men who are raised in a non-alcoholic home have 4 times the average rate of alcoholism, while sons of male non-alcoholics who were raised in alcoholic homes have only the population average rate of alcoholism. Genetics has been estimated to cause at least half of what determines if someone will have addiction as an adult or not.
But to get to how genetic testing will help in addiction treatment, we have to have an explanatory model of what’s happening biologically in addiction. For that we need the concept of dopamine tone.
In the reward centers of our brains there is a group of cells that make a chemical called dopamine. They use the dopamine to send a signal to another group of cells. When there’s enough dopamine everything is all right; we can enjoy ourselves, pay attention, remember things, have motivation, and feel we have enough. When there’s not enough dopamine we feel the opposite of those things. It should come as no surprise to anyone that all the behaviors and drugs associated with addiction have been shown to raise the activity at the cells that receive the dopamine signal. So it should be of critical importance to us to know what causes dopamine tone to be normal or low.
That’s a bit more than I can put in this small space, but it’s explained in my book, Questions and Answers on Addiction, if you’re interested. Suffice it to say here that there are multiple receptors, enzymes, and other proteins in the brain that go into determining someone’s dopamine tone. And here’s the kicker: each of those things is genetically determined to function at a certain rate. So knowing what each protein does to dopamine tone, and knowing what the genetics of that protein are, we can make some inferences about what certain genetic differences might do to a person’s dopamine tone.
Knowing that, we can develop a model of medical treatment of addiction that goes far beyond what has been available before. Instead of focusing on stopping the drug use, we can focus on stopping the symptoms that caused the drug use. Instead of focusing on one drug, we can focus on the whole illness. Instead of a doctor trying the first medicine to see if it works and then going down a random list of alternatives, we have a better chance of picking the right medication first.
So if you believe that addiction is a primary chronic illness, and not merely a moral failing or a chronic intoxication of the brain, then it makes sense to look at the genetics. That is, it makes sense if we actually want a solution.