Advancing the genomic prediction of antide-pressant and antipsychotic treatment outcomes

Treatment response to antipsychotics and antidepressants varies considerably between treated individuals, and recent evidence suggests that treatment response and non-response to psychotropic medications as well as their metabolic side effects have a genetic component beyond traditional pharmacogenetics. However, the largest genome-wide association studies (GWASs) on treatment response to antipsychotics and antidepressants to date have not been able to identify any robustly replicated genetic markers. Today, predictors of psychotropic drug response only include Cytochrome P450 enzymes and have limited predictive power, hence the choice of medication is still based on a trial-and-error approach.