As mental health care becomes more mainstream, a growing number of people are wondering if it’s possible to predict psychiatric illness based on genetics.

Genetic testing. Mayo Clinic. April 14, 2020.

Research shows that by examining a patient’s DNA, doctors can identify changes in the genetic code that may result in disease or illness.

 

While this testing may be used to rule out certain diseases, it’s not yet possible to determine whether a person will develop psychiatric illness based on their genetic profile. However, such testing could possibly prove helpful in treating such illnesses.

 

Improving medication choice with genetic testing

Although we cannot yet predict the eventual onset of psychiatric illness based on genetic mutations alone, genetic testing may help reveal which psychiatric medications may benefit patients most.

Genetic testing to improve psychiatric medication choice. Psychiatry.org. February 6, 2019.

In general, medication selection is a trial-and-error process. However, because a person’s genetic makeup can influence the effectiveness of medications, genetic testing is being increasingly explored as a way to determine which psychiatric medications may benefit patients most.

 

There may be future potential; while tests like these have not been approved by the US Food and Drug Administration, some, including GeneSight, are marketed to healthcare professionals as a method of identifying the most therapeutic drug recommendations.

Pyzocha N. Genesight psychotropic genetic testing for psychiatric medication selection. Am Fam Physician. 2021;104(1):89–90.

 

Pharmacogenomic tests often use proprietary algorithms to assess pharmacodynamic and pharmacokinetic relationships. However, different aspects of such tests—such as specificity and sensitivity measures, metabolizer status, and blood medication levels—are not always clear.

George Zubenko, MD, PhD, coauthor of a 2018 JAMA Psychiatry editorial on the use of pharmacogenetic tests for psychiatric treatment, wrote in a statement, “Doctors, patients, and family members should understand that the jury is out on whether [pharmacogenetic] testing improves good psychiatric care performed by board-certified psychiatrists.”

Zubenko GS, Sommer BR, Cohen BM. On the marketing and use of pharmacogenetic tests for psychiatric treatment. JAMA Psychiatry. 2018;75(8):769–770.

 

Unfortunately, consumer marketing of genetic tests may lead some to assume such tests may accurately determine which medications will work best. This concept has not been empirically confirmed in any study to date.

 

Family history and genetic counseling

Family history of mental health disorders remains an important risk factor for developing psychiatric problems.

Looking at my genes: what can they tell me about my mental health? National Institute of Mental Health. Updated 2020.

Mental health problems tend to run in families; this, coupled with the presence or absence of other variables, has a much higher predictive value than current genetic tests.

 

Genetic counseling may be beneficial for some patients and their families.

Evidence-based genetic counseling for psychiatric disorders: a road map. Cold Spring Harb Perspect Med. 2020;10(6):a036608.

Unlike genetic testing, genetic counseling helps people understand the factors in their own genetic makeup that may result in the development of disease.

 

Genetic counselors can help people overcome feelings of guilt that may occur if others in the family develop the same condition.