Understanding Your Genetic Test:
A Patient Guide
Mental health conditions are among the most heritable in medicine. Schizophrenia, bipolar disorder, and autism spectrum disorder each carry heritability estimates around 80%, while major depression and anxiety disorders have lower but still substantial genetic contributions (40 to 70%). Yet despite decades of research, translating genetic knowledge into everyday psychiatric practice has proven far more complex than in fields like oncology or cardiology.
Genetic testing in psychiatry is one of the most exciting tools we now have to help personalize your treatment. This guide explains what the test looks at, how it works, and what your results mean for you.
What Is Genetic Testing for Mental Health?
Genetic testing is a simple test, usually a cheek swab, that looks at your DNA to help your provider choose the right medication for you. Think of it like a personalized roadmap for your mental health treatment.
Everyone's body is a little different. Some people break down medications quickly, some slowly, and some at a normal pace. This test helps your provider figure out how your body handles certain psychiatric medications so they can pick the best one for you and avoid unnecessary side effects.
The FDA has already included genetic information on the labels of 28 psychiatric medications, and 10 of those include specific dosing guidance based on your genes. That means this science is already being used in real-world medicine.
How Does the Test Work?
Your provider or a staff member will swab the inside of your cheek. That's it -- no blood draw needed. The sample is sent to a lab, and results usually come back within a few days.
What Does the Test Look At?
The test looks at three types of genes.
Genes That Affect How Your Body Breaks Down Medication
These genes control how fast or slow your body processes certain drugs. If your body breaks down a medication too fast, it might not work well. If it breaks it down too slowly, you might get more side effects. Based on your results, you will be classified as a poor, intermediate, normal, or ultrarapid metabolizer, which tells your provider whether to adjust your dose.
Here is what each gene does:
Metabolism Genes
- CYP2D6
- Plays a role in breaking down many antidepressants (like venlafaxine and paroxetine), antipsychotics (like aripiprazole, risperidone, and haloperidol), and ADHD medications (like atomoxetine). One of the most important genes in psychiatric medication metabolism.
- CYP2C19
- Helps break down common antidepressants like escitalopram, citalopram, and sertraline, as well as some anti-anxiety medications. The other most important gene tested.
- CYP3A4
- The most abundant drug-processing enzyme in your liver. It helps metabolize a wide range of medications, including some antidepressants, anti-anxiety medications (like alprazolam and midazolam), and antipsychotics.
- CYP1A2
- Processes certain antidepressants (like fluvoxamine and duloxetine) and the antipsychotic clozapine. Smoking can also affect how this enzyme works.
- CYP2B6
- Involved in breaking down bupropion (Wellbutrin) and some other medications.
- CYP2C9
- Helps process certain mood stabilizers (like valproic acid) and some antidepressants. Also important for non-psychiatric medications like warfarin (a blood thinner).
- UGT1A4
- A "phase II" enzyme that works after the initial breakdown step to help your body clear medications. It plays a role in processing certain antipsychotics (like clozapine and olanzapine), tricyclic antidepressants, and the mood stabilizer lamotrigine.
- UGT2B15
- Another phase II enzyme that helps your body clear certain anti-anxiety medications like oxazepam and lorazepam, as well as the mood stabilizer lamotrigine.
- CES1A1 (Carboxylesterase 1)
- The most abundant drug-processing enzyme of its kind in the liver. In psychiatry, it is most relevant for breaking down methylphenidate (Ritalin/Concerta), a common ADHD medication.
Genes That Affect How Medications Work in Your Body
These genes can give your provider clues about whether a certain medication is more or less likely to work for you, or whether you might be at higher risk for certain side effects.
Pharmacodynamic Genes
- SLC6A4
- Related to how your brain uses serotonin, a chemical involved in mood.
- HTR2A
- Related to serotonin receptors in the brain.
- ADRA2A
- Related to a brain chemical called norepinephrine, which affects attention and focus.
- HLA-A and HLA-B
- Immune system genes. Certain versions of these genes can increase the risk of a rare but serious skin reaction to specific medications (like carbamazepine). Knowing your result helps your provider avoid prescribing a medication that could cause this reaction.
Informational Gene
COMT is involved in breaking down brain chemicals like dopamine. It is included for informational purposes.
How Will My Results Look?
Your report sorts medications into three color-coded categories:
Green: Use as directed
No gene-related reasons to adjust these medications.
Yellow: Use with caution
These medications may need a dose change or closer monitoring based on your genes.
Red: Use with increased caution
Your genes suggest these medications are more likely to cause problems or may not work as expected at standard doses. This does not mean you can never take a red medication. It means your provider will want to be more careful with dosing or monitoring.
What This Test Can and Cannot Do
What it CAN do
- Help narrow down which medications may work best for you
- Reduce the trial-and-error process of finding the right medication
- Identify medications that might cause more side effects for you
- Flag rare but serious risks (like the HLA-related skin reaction)
What it CANNOT do
- Diagnose any mental health condition
- Guarantee that a medication will work
- Replace your provider's clinical judgment
Your provider considers many factors beyond genetics, including your symptoms, medical history, other medications, and lifestyle.
Frequently Asked Questions
Will my results ever change?
No. Your DNA stays the same throughout your life, so you only need this test once.
Is my genetic information private?
Yes. Your results are part of your medical record and are protected by the same privacy laws (like HIPAA) that protect all your health information.
Does insurance cover this test?
Coverage varies by insurance plan. Many plans, including Medicare, offer coverage for genetic testing. Financial assistance programs may also be available. Ask your provider's office for details.
Does this test tell me if I'll get a mental health condition?
No. This test only looks at how your body handles medications. It does not predict whether you will develop any condition.
What if I'm already on a medication that shows up in the yellow or red category?
Do not stop taking your medication without talking to your provider first. If your current medication is working well for you, your provider may decide to keep you on it. The test is one piece of the puzzle, not the whole picture.
What Happens Next?
After your provider receives your results, they will review them with you and discuss what the findings mean for your treatment plan. Come prepared with any questions you have. Remember, this test is a tool to help guide your care, and your provider's expertise and your own experience with medications are just as important.
Alice Tran, PMHNP-BC offers genetic testing as part of personalized psychiatric care across Virginia via telehealth. Book an appointment or send a message with questions.
See also: Services at Alice Tran Psychiatric Care · Lab Testing in Psychiatry · What Is Medication Management?
Anh Tran (Alice), PMHNP, FNP-BC
Dual Board-Certified Family and Psychiatric Nurse Practitioner
Alice is a dual board-certified PMHNP and FNP licensed in Virginia. She earned dual master's degrees in psychiatric and family nursing and completed advanced clinical training under Dr. Errol Segall, MD, a highly respected psychiatrist with more than 50 years of experience. Alice provides compassionate, evidence-based psychiatric care through secure telehealth appointments across Virginia, with an office conveniently located in Northern Virginia. Alice specializes in treating ADHD, anxiety, depression, and other common mental health conditions. She is committed to providing culturally responsive care and is fluent in both English and Vietnamese. Learn more →