More than 600 genes are linked to antisocial behavior and addiction, according to one of the largest genetic studies of its kind. Researchers studied genetic data from 1.5 million people of European descent. They found genes tied to impulsive behavior and a higher risk of addiction. No single gene decides it. Hundreds work together.
Summary: Some behavior traits are passed down in humans. So genes affect how people act in certain situations. GWAS (large studies that scan the whole genome) now make it possible to find which genes are linked to which behavior traits. Any behavior trait is known to be shaped by several hundred genes working together. In one of the largest studies of its kind, researchers studied data from 1.5 million Europeans. They looked for genes linked to impulsive behavior and higher addiction risk. They found 600 genes often tied to antisocial behavior. Researchers think this will help them design help aimed at specific groups. It may also help people get the right help sooner.
There is no doubt that genes affect social behavior. You can see it in how the two sexes respond differently to stress. But a certain behavior may also change how genes are switched on. How much genes shape behavior is still debated. That is especially true in areas like opioid addiction treatment, where genes and surroundings both play big roles.
Early studies on how genes shape traits looked at small animals or insects with less genetic information. Those studies confirmed the link between behavior and genes. So it was assumed humans would be no exception. Still, humans are far more complex1.
Genes shape how a person responds to a bad or good environment. They control how sensitive the response is. So some people fit a given environment better than others. Often, these inherited traits only show up in certain situations2.
Studying the link between genes and specific behavior takes huge amounts of data.
Studying the genes of a few people would not help. Studying the genes of millions does. With the genetic data of millions, you can find gene patterns tied to a behavior or to a risk. That is where Genome-Wide Association Studies (GWAS) come in3.
With GWAS, you can search the whole genome using SNPs (single-letter differences in DNA). You may look for similar genes in a group with a certain behavior. Or you may look for genes that are always missing in people with the opposite trait.
Studies also show that any trait is usually linked to many genes, with each gene adding its bit.
Is there an addiction gene? What a study of 1.5 million people found
In the new study, researchers tried to find genes linked to self-control and addiction. They used the GWAS data of 1.5 million Europeans4.
They found that about 600 genes were linked to a much higher risk of impulsive behavior. So these genes can help predict the risk of substance abuse, obesity, HIV infection, suicide, antisocial behavior and much more.
Of course, no gene predicts anything a hundred percent. It is vital to know that genes do not code for a certain kind of social behavior. All these genes do is raise a person’s risk of certain conditions. Genes set the stage. They decide how the brain is wired and how it reacts to stress. That puts some people at higher risk of certain conditions.
It is the largest study of its kind. Researchers think it may matter in several ways. It may help build health care plans that step in early for people at risk. It could also help create so-called personalized medicines.
But a genetic tendency toward impulsivity or less self-control is not always bad. In some situations, it can be a very useful trait. For example, some of the most successful people, from CEOs to military generals, may be big risk takers.
So these findings are not meant to label people as good or bad. This kind of study may simply help people understand their strengths and weaknesses.
Frequently asked questions
Is addiction genetic?
In part. Genes do not code for addiction itself. They raise a person’s risk. In one of the largest studies of its kind, researchers used genetic data from 1.5 million Europeans. They found about 600 genes tied to impulsive behavior and a higher risk of addiction. No single gene is 100% predictive. Each one adds only its bit.
Is addiction inherited or learned?
Both play a role. Genes shape how the brain is wired and how it reacts to stress. Some inherited traits only show up in certain situations. At the same time, behavior can change how genes are switched on, and surroundings carry real weight alongside genes. Inherited genes raise the risk. They do not decide the outcome.
Who is more prone to addiction?
People who carry genes linked to impulsivity and weaker self-control face a higher risk. The same genes help predict risk for substance abuse, obesity, HIV infection, suicide and antisocial behavior. That tendency is not a verdict on character. The same risk-taking streak can show up in successful CEOs and military generals. Knowing it helps a person understand their strengths and weaknesses.
Related reading
Alcohol dependence genes tied to rapid Alzheimer's · Groups at Greater Risk of Opioid Addiction: UC Study · Drug Addiction Treatment, St. Louis
References
1. Kendler KS, Greenspan RJ. The Nature of Genetic Influences on Behavior: Lessons From “Simpler” Organisms. AJP. 2006;163(10):1683-1694. doi:10.1176/ajp.2006.163.10.1683
2. Reiss D, Leve LD, Neiderhiser JM. How Genes and the Social Environment Moderate Each Other. Am J Public Health. 2013;103(Suppl 1):S111-S121. doi:10.2105/AJPH.2013.301408
3. Genome-Wide Association Studies (GWAS). Genome.gov. Accessed November 15, 2021. https://www.genome.gov/genetics-glossary/Genome-Wide-Association-Studies
4. Karlsson Linnér R, Mallard TT, Barr PB, et al. Multivariate analysis of 1.5 million people identifies genetic associations with traits related to self-regulation and addiction. Nat Neurosci. 2021;24(10):1367-1376. doi:10.1038/s41593-021-00908-3