Neuromuscular diseases: muscleMyotonic dystrophy: RNA-mediated muscle diseaseWheeler, Thurman M; Thornton, Charles AAuthor Information Department of Neurology, University of Rochester, Rochester, New York, USA Correspondence to Charles Thornton, Box 673 URMC, 601 Elmwood Avenue, Rochester, NY 14618, USA fax: +1 585 273 1255; e-mail: email@example.com Current Opinion in Neurology: October 2007 - Volume 20 - Issue 5 - p 572-576 doi: 10.1097/WCO.0b013e3282ef6064 Buy Metrics Abstract Purpose of review The aim of this review is to highlight recent progress in elucidating the disease mechanism in myotonic dystrophy type 1 and type 2. Recent findings Research on myotonic dystrophy has led to the recognition of a novel RNA-mediated disease process. In myotonic dystrophy it is the RNA rather than protein product of a disease gene that has deleterious effects on muscle cells. These unusual RNAs, which contain a long expanse of CUG or CCUG repeats, have far reaching effects on cell function by influencing the biogenesis of other cellular RNAs. One aspect of RNA metabolism that is particularly affected is the regulation of alternative splicing. By this mechanism, effects of myotonic dystrophy repeat expansions impact many different pathways, triggering a complex set of signs and symptoms. Summary The genetic lesion in myotonic dystrophy does not eliminate an essential muscle protein. Instead, it induces a defect of RNA processing that is potentially reversible. The nature of this disease process raises the possibility that myotonic dystrophy, among genetic disorders, may be unusually susceptible to treatment using non-gene-therapy approaches. © 2007 Lippincott Williams & Wilkins, Inc.