Musculoskeletal Disease in MDA5‐Related Type I Interferonopathy: A Mendelian Mimic of Jaccoud's Arthropathy

Abstract

These cases highlight the significant musculoskeletal involvement that can be associated with mutations in MDA-5, and emphasize the value of testing for up-regulation of IFN signaling as a marker of the underlying molecular lesion. Our data indicate that both Singleton-Merten syndrome and neuroinflammation described in the context of MDA-5 gain-of-function constitute part of the same type I interferonopathy disease spectrum, and provide possible novel insight into the pathology of Jaccoud's arthropathy.