We applied two drugs to KCNQ3 OE and WT OE33 cell lines, the KCNQ-specific inhibitor linopirdine (32), and the more broad inhibitor amitriptyline (33), which inhibits a large number of proteins including KCNQ3, is FDA-approved, and is clinically available to treat depression (34). This evidence concerns the gene KCNQ3 and major depressive disorder.