A newly published analysis shows that the combinatorial approach available in the GeneSight Psychotropic test, from Myriad Genetics, Salt Lake City, is better than single-gene testing at predicting patient outcomes and medication blood levels.

Myriad’s GeneSight test evaluates how variations in multiple genes may influence an individual’s outcomes with certain FDA-approved medications commonly prescribed to treat depression, anxiety, and other psychiatric conditions. Using data from the Genomics Used to Improve Depression Decisions (GUIDED) randomized-controlled trial, the study evaluated the ability of the combinatorial approach available in the GeneSight Psychotropic test to predict patient outcomes and medication blood levels compared to Clinical Pharmacogenetics Implementation Consortium (CPIC) single-gene recommendations. CPIC recommendations are based on either CYP2C19 and CYP2D6, which are genes that are involved in how the body metabolizes medications commonly used to treat depression and other mental illnesses.

The study included two types of analyses:

  • Patient Outcomes. The largest improvement in symptoms and the highest response and remission rates were observed for patients who were changed from medications with significant gene-drug interactions to medications with no or moderate gene-drug interactions indicated by the combinatorial GeneSight test.
  • Medication Blood Levels. The analysis of the combinatorial pharmacogenomic test and single-gene guidelines showed the predictive ability of the GeneSight combinatorial approach was better.

“Our analysis demonstrated the superior ability of combinatorial pharmacogenetic testing to predict variation in medication blood levels may result in improved patient outcomes,” says lead author Anthony J. Rothschild, MD, the Irving S. and Betty Brudnick Endowed Chair and Professor of Psychiatry at the University of Massachusetts Medical School. “We believe this study provides compelling evidence of the clinical validity of the combinatorial pharmacogenomic test for patients with major depressive disorder, who have at least one prior medication failure.”

“This analysis demonstrates that the combinatorial approach of the GeneSight test more accurately predicts blood drug levels and identifies more patients with significant gene-drug interactions who would be missed by single-gene testing,” says Mark Pollack, MD, chief medical officer, Myriad Neuroscience. “Combinatorial pharmacogenomics like the GeneSight test should become the standard-of-care to help physicians understand gene-drug interactions that could improve care for people with depression, anxiety and other conditions.”

The GUIDED study, the largest pharmacogenomic randomized controlled trial in mental health, showed that patients whose doctors received GeneSight results had significantly improved response and remission rates from depression, compared to treatment as usual.

For more information, visit Myriad Genetics


Rothschild AJ, Parikh SV, Hain D, et al. Clinical validation of combinatorial pharmacogenomic testing and single-gene guidelines in predicting psychotropic medication blood levels and clinical outcomes in patients with depression. Psychiatry Res. 2021;296:113649. doi: 10.1016/j.psychres.2020.113649.