Is Psychopathy Genetic?

Barbara Stevens
Gene Talk
Published in
5 min readMay 24, 2023

Are psychopaths born or made? Despite decades of research, the origins of psychopathy remain elusive, with some experts attributing the condition to a complex interplay of genetic, environmental, and neurobiological factors.

As the debate over the nature vs. nurture of psychopathy continues, many are left wondering if this condition is truly determined by our genes or if the experiences and circumstances of our lives shape it.

In this article, we delve into the latest research on the genetic basis of psychopathy and examine the evidence for and against a genetic cause.

Did You Know?

Many behavioral and personality traits have strong genetic influences. Learn more:

Psychopaths are individuals with a lack of empathy, manipulation, impulsiveness, and violence.

According to the American Psychological Association (APA), about 1.2% of American men and up to 0.7% of American women may have clinical psychological traits.

What Is Psychopathy?

Psychopathy is a severe form of Antisocial Personality Disorder (ASPD).

This condition is marked by a lack of empathy, antisocial skills, abnormal emotional responses, and an inability to control impulses.

These conditions are, together, called callous-unemotional traits.

Up to 30% of criminal offenders worldwide exhibit such traits.

According to experts, early measures of these callous-unemotional traits may predict violent criminal activities in the future.

Current Understanding Of Causes Of Psychopathy

Right now, scientists think that changes in brain structures may be a strong reason why some people develop psychopathic traits and others don’t.

There following are two factors that may encourage changes to the brain structure and circuits.

  1. Genetics
  2. Environment

No one gene or particular environmental factor could lead to psychopathic tendencies in a person.

Instead, a combination of genes and environmental conditions may increase the risk of developing psychopathy.

Is Psychopathy Genetic?

Psychopathy is not entirely genetic. No one gene causes the condition.

Instead, researchers believe that several genes may play roles in changing brain structures and circuits.

Together, these increase the risk of psychopathic behavior in the individual.

A person could be a carrier of these psychopathic gene variants but not exhibit the traits themselves.

They could pass the genes to their children, who, in turn, could be simply carriers or express the trait.

Genes Linked To Psychopathy

Several genes are linked to psychopathy, including ANKK1, DRD2, MAOA, COMT, and 5-HTTLPR.

Out of these, the MAOA gene is of particular interest.

Is There A Psychopath Gene?

Many studies suggest that changes in the MAOA (monoamine oxidase A) gene may increase aggressive or violent behavior in people, leading to possible psychopathic behavior.

The MAOA gene gives instructions to produce the monoamine oxidase enzyme.

This enzyme breaks down signaling chemicals in the brain like dopamine, serotonin, epinephrine, and noradrenaline.

These chemicals control mood, determine sleep quality, and act on emotional responses.

Individuals with a particular variant of this gene — the MAOA-L, may produce lower quantities of the monoamine oxidase enzyme.

As a result, there may be an excess build-up of these signaling chemicals in the brain, leading to different impulsive behaviors.

In fact, in 2009, an Italian court reduced the sentence of a convicted murderer by one year, accepting the claim that he had a genetic version of the MAOA gene that encouraged aggressive behavior.

Will everyone with this variant of the MAOA-L gene show psychopathic traits?

Not necessarily!

This version of the MAOA gene only increases the likelihood of exhibiting psychopathic traits with certain environmental triggers.

Can You Inherit Psychopathy?

Some genetic changes may encourage aggressive behavior and a lack of empathy, which can be passed on through generations.

Not all children who inherit these gene changes turn into psychopaths, though. Environmental factors play a role in determining whether or not a person develops these inherited traits.

A 2011 study reports that, genetically, fathers may pass psychopathic traits to their male offspring.

Having a criminally-convicted father increases the risk of male children showing psychopathic traits.

Epigenetics (Gene-environment Interactions) In Psychopathy

Epigenetics describes how your behaviors and environmental factors can cause changes that affect how your genes work.

Epigenetic changes are reversible and can be altered by behavioral changes or environmental interactions.

Several studies suggest epigenetics could be the connecting factor between genetic and environmental factors that may cause psychopathy.

Genes and environment are tightly intertwined and affect one another when determining psychopathic behavior in individuals.

Studies say that one factor can influence the other.

For instance, a child growing up in an antisocial environment may experience epigenetic changes and develop psychopathic behaviors.

Similarly, a child with psychopathy-causing genetic changes may seek out antisocial environments that support the behavior.

Brain Biology and Psychopathy

Both genetics and environmental factors don’t directly impart psychopathic traits in people. Instead, these change how the brain is structured and circuited and lead to such characteristics.

According to experts, one part of the brain that is of specific interest in psychopathy is the amygdala. This region controls empathy, social responsiveness, and fear of outcomes.

These experts feel that due to specific genetic changes and environmental factors, the amygdala may be formed differently or change its functioning over time.

When this region of the brain does not work effectively, the person cannot emote, fear, or show empathy as well as others, leading to antisocial behaviors.

Environmental Contributions To Psychopathy

Despite strong genetic links to psychopathy, studies claim that up to 50% of the differences in antisocial behaviors, including psychopathic traits, come from environmental influences.

  • Prenatal and postnatal environment
  • Neighborhood
  • Family setup

A 2015 meta-analysis that studied heritability traits in twin studies reports that 14–30% of conduct disorders are due to environmental factors.

Future Directions On Psychopathy Research

Identifying gene variants associated with psychopathy can help with early intervention in terms of providing the right environment or therapeutic support.

However, researchers have identified only a handful of genetic variants associated with psychopathy.

More genes could play equally important roles in causing the condition, which is yet to be discovered.

Future research on psychopathy will focus more on epigenetics and try to understand precise interactions between genes and the environment.

Such an understanding can help reduce the risk of individuals developing psychopathic traits.

Summary: Is Psychopathy Genetic?

Specific gene variants can increase one’s risk of developing psychopathy, and one can inherit these genes from the parents.

However, environmental factors like prenatal exposure, parenting techniques, neighborhood, and childhood can influence psychopathic traits equally.

Therefore, both genes and environment are interrelated and are equally important in determining whether or not a person grows to develop antisocial behaviors, including psychopathy.

References

Originally published in https://www.xcode.life/genes-and-personality/is-psychopathy-genetic/

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Barbara Stevens
Gene Talk

Content Writer with interest in genetics, health, fitness, and fashion.