This is substantiated by a KCNQ2 knock-out mouse model that shows spontaneous seizures and behavioral hyperactivity (Peters et al., 2005); by finding of two patients with psychomotor retardation and convulsions with a 8,35 Mb deletion encompassing KCNQ3 (Verheij et al., 2009); and by the association of markers close to KCNQ3 with bipolar disorder (Avramopoulos et al., 2004; Zandi et al., 2008; Zhang et al., 2010). This evidence concerns the gene KCNQ2 and bipolar disorder.