Human genetics studies have shown the association of the PACAP gene with psychiatric disorders, such as bipolar disorder (McInnes et al., 2001), schizophrenia (Hashimoto et al., 2007), depressive disorder (Hashimoto et al., 2010), and PTSD (Ressler et al., 2011). This evidence concerns the gene ADCYAP1 and schizophrenia.