Studies in laboratory animals, including lower mammals and primates, have shown that an up-regulation of the CRF system can underlie anxiety- and depression-like phenotypes (Kalin et al., 2000; Strome et al., 2002; Servatius et al., 2005; Jaferi and Bhatnagar, 2007), and lead to excessive alcohol drinking (Nie et al., 2004; Breese et al., 2005; Funk C.K. et al., 2006; Hansson et al., 2006; Sommer et al., 2008). The gene discussed is CRH; the disease is major depressive disorder.