TREX1 and Aicardi-Goutieres syndrome: To explain why trex1-deficient mice develop inflammatory myocarditis, Crow et al. demonstrated that the mutation in the trex1 gene that abolished TREX1 enzyme activity was responsible for the development of Aicardi-Goutieres syndrome (AGS), a severe neurological brain disease with high levels of IFN-α in cerebrospinal fluid or serum, suggesting that TREX1 is a suppressor of DNA DAMP-mediated inflammatory responses (Crow et al., 2006).