Intriguingly, wild-type MDA5 has limited ability to recognize IRAlus and inefficiently forms the filaments, compared to gain-of-function (GOF) mutant MDA5, which has enhanced RNA binding affinity and is often found in patients with inflammatory diseases, including Aicardi–Goutières syndrome (AGS)30. The gene discussed is IFIH1; the disease is Aicardi-Goutières syndrome.