Genetics is just one of several factors thought to influence personality disorder development. Life experiences, family dynamics, coping mechanisms, and social learning may all be contributing factors.

Personality disorders are mental health conditions featuring long-term unhelpful patterns of thinking and behaving, outside of what’s typical or expected. They can feature behaviors that are eccentric and differ from one’s cultural expectations. People with a personality disorder may also experience intense emotions or react spontaneously.

Medical professionals have listed 10 formal personality disorders in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, text revision (DSM-5-TR). This is a clinical guidebook that provides diagnostic criteria for clinicians around the world.

These include:

Experts believe personality disorders involve complex dynamics between genetics, environmental factors, social exposures, and psychological factors.

Medical professionals haven’t linked any personality disorder solely to genetics or a single gene. But genetics may influence the development of personality disorders for some people.

Personality traits, in general, are moderately heritable, meaning they can be traced back to genetic factors passed down within families or genetically related populations. However, other factors also influenced them.

The authors of some older research consider all 10 personality disorders in the DSM-5-TR to be modestly to moderately heritable. This doesn’t guarantee you’ll inherit a personality disorder if one of your parents received a diagnosis. However, it does mean you may have an increased chance of getting a diagnosis with a personality disorder if there’s a history of that disorder in your family.

Genetic factors passed down generationally aren’t the only way genetics can influence personality disorder development, however.

Epigenetics

How your genes express or your “epigenetics” may also be a factor. According to a 2018 review of research, changes in genetic expression over time can directly contribute to a variety of mental health conditions, including personality disorders.

Gene expression refers to the activation or silencing of a gene without altering its underlying DNA. Like controlling the flow of water from a faucet, external factors can regulate gene expression. Some external factors, like trauma, chronic stress, diet, and toxin exposure, can cause epigenetic changes throughout life.

Acquired alterations

It’s also possible to acquire genetic alterations that could contribute to the development of a personality disorder. Acquired genetic alterations develop after conception. Your parents’ DNA doesn’t pass these down.

Like changes in epigenetics, various factors throughout life can cause genetic alterations, such as infection, toxin exposure, or developmental errors during cell replication.

Heritability suggests having a family history of personality disorders increases your chance of also receiving a personality disorder diagnosis.

However, genetics alone don’t always account for why personality disorders run in families. Social learning and generational trauma may be other reasons why multiple people within a family receive a diagnosis of a personality disorder.

Social learning

Social learning is a psychological theory that suggests people learn new behaviors by modeling those seen in others. Under social learning theory, growing up in a household where you see personality disorder behaviors makes it more likely that you’ll adopt those behaviors yourself.

Generational trauma

Generational trauma may be another reason personality disorders appear in families. Generational trauma is a phenomenon where the effects of trauma get passed down from one generation to the next. It’s an experience that can affect epigenetics, which may influence personality disorder chance.

No. There are currently no genetic tests for personality disorders. While medical professionals have identified certain genes as potential candidates for future testing, more research is necessary to establish their link to personality disorder traits.

The best way to figure out if you have a personality disorder is to talk with a mental health professional.

How to get help with personality disorders

A mental health professional can help treat personality disorders. Psychotherapy, like cognitive behavioral therapy (CBT), can help you identify and restructure unhelpful patterns of thinking and behaving.

To find a mental health professional in your area, you can contact or visit the following resources:

Genetics is just one of several factors that can play a role in personality disorder development.

Inherited genetic factors, acquired genetic changes, and shifts in genetic expression over time may affect the likelihood of a doctor diagnosing a personality disorder.

Techniques like therapy can help those with personality disorders develop new coping mechanisms and improve their overall quality of life. You can keep learning about mental health over on our hub.