ADAR1 is essential for mouse development and regulation of cellular homeostasis [9–11], and in humans, mutations and dysregulation of ADAR1 activity is associated with a number of diseases, including cancer and Aicardi-Goutières syndrome, a severe autoimmune disease associated with spontaneous IFN production (i.e. interferonopathy)[12–14]. This evidence concerns the gene ADAR and Aicardi-Goutières syndrome.