Genetic Link to Antidepressant Response Found

BACKGROUND: Researchers in recent years have been trying to identify genetic factors predicting a response to antidepressants. Previous studies have found evidence for the role of corticotrophin-releasing hormone (CRH) in depression. Based on previous findings, researchers have most closely focused on drugs that target serotonin transports, such as Prozac. None of these studies, however, focused on specific demographic groups such as Mexican-Americans or on stress-related genes such as CRH.

FINDINGS: Basing their study on 80 depressed Mexican-Americans in Los Angeles, the researchers found that depressed and highly anxious patients with a variant of the CRH gene (CRHR1) had a 70 percent greater reduction in anxiety and a 30 percent greater reduction in depression in response to the anti-depressants Prozac and desipramine than did patients without the gene variation in question.

IMPACT: The findings for the first time show an association between responses to specific anti-depressants and a stress-related gene. Physicians have generally taken a "hit and miss" approach to prescribing anti-depressants. The findings show promise in helping physicians tailor prescriptions to specific people.

AUTHOR: The lead author was Julio Licinio, professor of psychiatric and biobehavioral sciences at the David Geffen School of Medicine at UCLA.

JOURNAL: Molecular Psychiatry, available online Dec. 16 at http://www.nature.com/mp.

FUNDERS: National Institutes of Health and the Dana Foundation.