This is illustrated by mutations in SAMHD1 described as the cause of some cases of the Aicardi-Goutières syndrome, a rare autoimmune disease characterized by an IFN-stimulated gene expression signature that resembles a congenital viral infection and overlaps clinically and biochemically with the systemic lupus erythematosus (75). The gene discussed is SAMHD1; the disease is autoimmune disease.