Both PDE2A and PDE10A inhibitors are being studied in the clinic as potential treatments for schizophrenia (Siuciak et al., 2006), Huntington’s disease (Giampa et al., 2010), Parkinson’s disease (Niccolini et al., 2015), and other movement and neuropsychiatric disorders (Nishi and Snyder, 2010; Menniti et al., 2006). This evidence concerns the gene PDE10A and juvenile Huntington disease.