title: Primary and secondary dystonic syndromes: an update.
abstract: OBJECTIVE
  The dystonias are a common but complex group of disorders that show considerable variation in cause and clinical presentation. The purpose of this review is to highlight the most important discoveries and insights from across the field over the period of the past 18 months.
  
  
  RESULTS
  Five new genes for primary dystonia (PRRT2, CIZ1, ANO3, TUBB4A and GNAL) have made their appearance in the literature. New subtypes of neuronal brain iron accumulation have been delineated and linked to mutations in C19orf12 and WDR45, while a new treatable form of dystonia with brain manganese deposition related to mutations in SLC30A10 has been described. At the same time, the phenotypes of other forms of dystonic syndromes have been expanded or linked together. Finally, there has been increasing recognition of both the extramotor phenotype in dystonia and the part played by the cerebellum in its pathophysiology.
  
  
  CONCLUSIONS
  Recently, there has been unprecedented change in the scientific landscape with respect to the cause of various dystonic syndromes that is likely to make a direct impact on clinical practice in the near future. Understanding the genetic cause of these syndromes and the often wide phenotypic variation in their presentations will improve diagnosis and treatment. With time, these discoveries may also lead to much-needed progress in elucidating the underlying pathophysiology of dystonia.
authors.affiliation: Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK.
authors.forename: Gavin
authors.initials: G
authors.lastname: Charlesworth
authors.forename: Kailash P
authors.initials: KP
authors.lastname: Bhatia
mesh_terms: D000075368:Anoctamins; D002531:Cerebellum / Q000473:pathology; D018118:Chloride Channels; D004421:Dystonia / Q000145:classification / Q000235:genetics* / Q000473:pathology*; D044385:GTP-Binding Protein alpha Subunits / Q000235:genetics; D020022:Genetic Predisposition to Disease; D006801:Humans; D008565:Membrane Proteins; D009154:Mutation / Q000235:genetics*; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D010641:Phenotype; D014404:Tubulin / Q000235:genetics
chemical_list: C577591:ANO3 protein, human; D000075368:Anoctamins; D018118:Chloride Channels; C400423:Ciz1 protein, human; D044385:GTP-Binding Protein alpha Subunits; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; C569370:PRRT2 protein, human; C582076:TUBB4A protein, human; D014404:Tubulin; C084618:olfactory G protein subunit alpha olf