Table 1.

Current and potential applications of genomic testing in psychiatric practice

	Current Uses of Genomics Testing		Potential Applications of Genomics Testing
Clinical Activity	Treatment	Diagnosis	Risk Prediction	Prognosis
Genomic Testing Facilitates	Reduction in medication trial and error; maximization of clinical response and/or minimization of severe side effects	Differential Diagnosis	Prevention, early detection, early intervention, decreased duration of untreated disorder, improved clinical outcomes	Clinical management
Examples	For a patient identified as a CYP2C19 poor metabolizer, the maximum recommended dose of citalopram is 20 mg due to increased risk of cardiac arrhythmia. If genomic testing reveals such information, psychiatrists may prescribe a different medication or follow the FDA guideline of no more than 20 mg to decrease the likelihood of severe side effects.	If a patient diagnosed with schizophrenia is found to have a mutation in the ATP7B gene, this suggests the patient has been misdiagnosed, and actually suffers from Wilson disease, which may present with psychotic symptoms.	An asymptomatic research subject or patient with attenuated psychosis syndrome is identified with a 22q11.2 deletion, a copy number variant associated with schizophrenia. A psychiatrist could offer increased monitoring of symptoms, and depending on symptoms, could offer early interventions such as psychotherapy, social skills training, or even prophylactic pharmacological intervention if symptoms worsen.	Genomic tests may soon reliably identify variants associated with treatment-resistant depression or schizophrenia. If a patient is identified with variants that suggest an increased risk for treatment-resistant schizophrenia, clinicians could consider a more aggressive treatment approach such as prescribing clozapine at an earlier stage in treatment.