Because of the apparently important role of serotonin (5-HT) and noradrenaline (NA) in the treatment of depression (Nemeroff and Owens, 2009; Goddard et al., 2010), we sought to study these neurotransmitter systems in Wfs1-deficient mice using pharmacological, genetic and biochemical methods. Here, WFS1 is linked to major depressive disorder.