LETTER TO THE EDITOR Reply to: Myopathic (not neuropathic) electrophysiologic abnormalities in dynamin 2-related centronuclear myopathy

doi:10.1093/brain/awl312 We are very grateful for the valuable comments on the electrophysiological data on DNM2-CNM. The author is absolutely right that fibrillations due to muscle fibre necrosis and reduced compound motor action potentials (muscular atrophy) can also be observed in some myopathies, most commonly in muscular dystrophies or inflammatory myopathies. However, (segmental) necrosis and regeneration— classical findings in muscular dystrophies—are usually not observed in muscle biopsies of patients with CNM (Jeannet, 2004) or other congenital myopathies (CM). CM are histopathologically defined by characteristic structural abnormalities, such as an increased number of central nuclei in DNM2-CNM or core lesions in central or minicor