title: High-throughput mutational analysis of TOR1A in primary dystonia.
abstract: BACKGROUND
  Although the c.904_906delGAG mutation in Exon 5 of TOR1A typically manifests as early-onset generalized dystonia, DYT1 dystonia is genetically and clinically heterogeneous. Recently, another Exon 5 mutation (c.863G>A) has been associated with early-onset generalized dystonia and some DeltaGAG mutation carriers present with late-onset focal dystonia. The aim of this study was to identify TOR1A Exon 5 mutations in a large cohort of subjects with mainly non-generalized primary dystonia.
  
  
  METHODS
  High resolution melting (HRM) was used to examine the entire TOR1A Exon 5 coding sequence in 1014 subjects with primary dystonia (422 spasmodic dysphonia, 285 cervical dystonia, 67 blepharospasm, 41 writer's cramp, 16 oromandibular dystonia, 38 other primary focal dystonia, 112 segmental dystonia, 16 multifocal dystonia, and 17 generalized dystonia) and 250 controls (150 neurologically normal and 100 with other movement disorders). Diagnostic sensitivity and specificity were evaluated in an additional 8 subjects with known DeltaGAG DYT1 dystonia and 88 subjects with DeltaGAG-negative dystonia.
  
  
  RESULTS
  HRM of TOR1A Exon 5 showed high (100%) diagnostic sensitivity and specificity. HRM was rapid and economical. HRM reliably differentiated the TOR1A DeltaGAG and c.863G>A mutations. Melting curves were normal in 250/250 controls and 1012/1014 subjects with primary dystonia. The two subjects with shifted melting curves were found to harbor the classic DeltaGAG deletion: 1) a non-Jewish Caucasian female with childhood-onset multifocal dystonia and 2) an Ashkenazi Jewish female with adolescent-onset spasmodic dysphonia.
  
  
  CONCLUSIONS
  First, HRM is an inexpensive, diagnostically sensitive and specific, high-throughput method for mutation discovery. Second, Exon 5 mutations in TOR1A are rarely associated with non-generalized primary dystonia.
authors.affiliation: Department of Neurology, University of Tennessee Health Science Center, Memphis, TN, USA. jianfengxiao@gmail.com
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Xiao
authors.forename: Robert W
authors.initials: RW
authors.lastname: Bastian
authors.forename: Joel S
authors.initials: JS
authors.lastname: Perlmutter
authors.forename: Brad A
authors.initials: BA
authors.lastname: Racette
authors.forename: Samer D
authors.initials: SD
authors.lastname: Tabbal
authors.forename: Morvarid
authors.initials: M
authors.lastname: Karimi
authors.forename: Randal C
authors.initials: RC
authors.lastname: Paniello
authors.forename: Andrew
authors.initials: A
authors.lastname: Blitzer
authors.forename: Sat Dev
authors.initials: SD
authors.lastname: Batish
authors.forename: Zbigniew K
authors.initials: ZK
authors.lastname: Wszolek
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Uitti
authors.forename: Peter
authors.initials: P
authors.lastname: Hedera
authors.forename: David K
authors.initials: DK
authors.lastname: Simon
authors.forename: Daniel
authors.initials: D
authors.lastname: Tarsy
authors.forename: Daniel D
authors.initials: DD
authors.lastname: Truong
authors.forename: Karen P
authors.initials: KP
authors.lastname: Frei
authors.forename: Ronald F
authors.initials: RF
authors.lastname: Pfeiffer
authors.forename: Suzhen
authors.initials: S
authors.lastname: Gong
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhao
authors.forename: Mark S
authors.initials: MS
authors.lastname: LeDoux
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004252:DNA Mutational Analysis; D020821:Dystonic Disorders / Q000235:genetics*; D005091:Exons; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D018832:Molecular Chaperones / Q000235:genetics*; D009154:Mutation; D055815:Young Adult
chemical_list: D018832:Molecular Chaperones; C108175:TOR1A protein, human