title: Analysis of CAG repeat expansions in restless legs syndrome.
abstract: OBJECTIVE
  A relatively high prevalence of restless legs syndrome symptoms has been recently reported in a substantial proportion of patients affected with spinocerebellar ataxia type 3. Our aim was to investigate whether there is a common genetic etiology between restless legs syndrome and spinocerebellar ataxia type 3.
  
  
  METHODS
  Systematic differences in the number of spinocerebellar ataxia type 3 trinucleotide repeat were investigated by means of an association study. The relationship between the size of the expanded alleles and several clinical features was also considered.
  
  
  METHODS
  125 extensively characterized restless legs syndrome patients compared with 188 healthy controls matched for ethnic background.
  
  
  METHODS
  N/A.
  
  
  RESULTS
  No CAG repeat expansions in the pathologic or intermediate range were detected in any of the examined subjects, including patients and controls. A similar allelic distribution was observed in both groups (Mann-Whitney U test = 78406; P = 0.99). Moreover, stratification analyses of the patients' samples according to different clinical and polysomnographic variables disclosed no significant differences.
  
  
  CONCLUSIONS
  These results do not provide evidence toward an involvement of large CAG trinucleotide expansions at the spinocerebellar ataxia type 3 locus in idiopathic restless legs syndrome.
authors.affiliation: Centre d'étude du sommeil, Hôpital du Sacré-Caeur de Montréal, Centre de recherche en sciences neurologiques, Université de Montréal, Québec, Canada.
authors.forename: Alex
authors.initials: A
authors.lastname: Desautels
authors.forename: Gustavo
authors.initials: G
authors.lastname: Turecki
authors.forename: Jacques
authors.initials: J
authors.lastname: Montplaisir
authors.forename: Katéri
authors.initials: K
authors.lastname: Brisebois
authors.forename: Amélie K
authors.initials: AK
authors.lastname: Desautels
authors.forename: Benoît
authors.initials: B
authors.lastname: Adam
authors.forename: Guy A
authors.initials: GA
authors.lastname: Rouleau
mesh_terms: D005260:Female; D005787:Gene Frequency / Q000235:genetics; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods; D012148:Restless Legs Syndrome / Q000175:diagnosis / Q000235:genetics*; D020754:Spinocerebellar Ataxias / Q000235:genetics; D018911:Trinucleotide Repeats / Q000235:genetics*; D014851:Wakefulness / Q000502:physiology