Desmin is a class-III intermediate filament found in muscle cells. In adult striated muscle desmin forms a fibrous network connecting myofibrils to each other and to the plasma membrane from the periphery of the Z-line structures. Defects in desmin are the cause of myopathy myofibrillar desmin-related (MFM-DES), also known as desmin-related myopathy (DRM). DRM is a neuromuscular disorder characterized by skeletal muscle weakness associated with cardiac conduction blocks, arrhythmias, restrictive heart failure, and by myofibrillar destruction with intracytoplasmic accumulation of desmin-reactive deposits in cardiac and skeletal muscle cells.