PDE4D has been etiologically implicated in the pathogenesis of other neuropsychiatric diseases associated with PFC dysfunction, with genome-wide association studies identifying point mutations in PDE4D with intellectual disability, major depression and anxiety disorders (Shifman et al., 2008; Lee et al., 2012b; Lindstrand et al., 2014). The gene discussed is PDE4D; the disease is major depressive disorder.