Mutations and dysregulation of a sterile alpha motif (SAM) and histidine-aspartic acid (HD) domain-containing protein 1 (SAMHD1) are associated with Aicardi Goutières syndrome (AGS) (9), an inherited autoimmune encephalopathic disorder, and several cancers (10), including leukemias (11–13), lymphomas (14–16), colorectal cancer (17), and lung cancer (18). The gene discussed is SAMHD1; the disease is Aicardi-Goutieres syndrome.