title: Clinical and genetic features of paroxysmal kinesigenic dyskinesia in Italian patients.
abstract: BACKGROUND
  Paroxysmal Kinesigenic Dyskinesia (PKD, OMIM 128200) is the most common type of autosomal dominant Paroxysmal Dyskinesias characterized by attacks of dystonia and choreoathetosis triggered by sudden movements. Recently PRRT2, encoding proline-rich transmembrane protein 2, has been described as the most frequent causative gene for PKD.
  
  
  METHODS
  We studied the incidence of PRRT2 mutations in a cohort of 16 PKD patients and their relatives for a total of 39 individuals.
  
  
  RESULTS
  We identify mutations in 10/16 patients and 23 relatives. In 27/33 the mutation was the c.insC649 p.Arg217Profs*8. In 6 individuals from 3 families we found three new mutations: c.insT27 p.Ser9*, c.G967A p.Gly323Arg and c.delCA215_216 p.Thr72Argfs*62. Family history was positive in 9 patients. The mean age of onset was 10 years. Attacks lasted from a few seconds to 1 min and ranged from several per day to some per week, and were generalised in all patients. The main distinctive features of mutation-negative patients were the sporadic occurrence, the absence of association with epilepsy or EEG abnormalities and the poor response to Carbamazepine or other antiepileptic agents.
  
  
  CONCLUSIONS
  We report the first cohort of Italian patients mutated in PRRT2 and we confirm that this is the most frequent gene involved in PKD.
authors.affiliation: Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy.
authors.forename: Costanza
authors.initials: C
authors.lastname: Lamperti
authors.affiliation: Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Invernizzi
authors.affiliation: Unit of Neuropediatry, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Solazzi
authors.affiliation: Unit of Neuropediatry, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Freri
authors.affiliation: Unit of Movement Disorders, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Carella
authors.affiliation: MRC Mitochondrial Biology Unit, Cambridge, UK.
authors.forename: Massimo
authors.initials: M
authors.lastname: Zeviani
authors.affiliation: Unit of Neuropediatry, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Zibordi
authors.affiliation: Unit of Neuropediatry, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Fusco
authors.affiliation: Unit of Neuropediatry, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Zorzi
authors.affiliation: Unit of Neuropediatry, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Granata
authors.affiliation: Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Garavaglia
authors.affiliation: Unit of Neuropediatry, The Foundation "Carlo Besta" Institute of Neurology IRCCS, Milan, Italy. Electronic address: nnardocci@istituto-besta.it.
authors.forename: Nardo
authors.initials: N
authors.lastname: Nardocci
mesh_terms: D000328:Adult; D002648:Child; D004421:Dystonia / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008875:Middle Aged; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics*; D010375:Pedigree; D044465:White People / Q000235:genetics*
chemical_list: D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C569370:PRRT2 protein, human
keywords: Autosomal dominant; Dystonia; Epilepsy; PRRT2; Paroxysmal kinesigenic dyskinesia