Recently, there has been an industry-wide effort to develop and test inhibitors of phosphodiesterase 10A (PDE10A) as a novel mechanism to ameliorate psychosis (Chappie et al., 2012; Jørgensen et al., 2013; Geerts et al., 2017; Jankowska et al., 2019). This evidence concerns the gene PDE10A and psychotic disorder.