We have previously observed hyperarousal and anxiety, as well as fear generalization and resistance to extinction in mice deficient for the GABA synthesizing enzyme glutamic acid decarboxylase (GAD)65 (Stork et al., 2000a; Bergado-Acosta et al., 2008; Sangha et al., 2009), suggesting that GABA synthesis is a critical factor for several PTSD-related phenomena. The gene discussed is GAD2; the disease is post-traumatic stress disorder.