title: Malaysian siblings with friedreich ataxia and chorea: a novel deletion in the frataxin gene.
abstract: BACKGROUND
  Friedrich ataxia (FRDA1) is most often the result of a homozygous GAA repeat expansion in the first intron of the frataxin gene (FRDA gene). This condition is seen in individuals of European, North African, Middle Eastern and Indian descent and has not been reported in Southeast Asian populations. Approximately 4% of FRDA1 patients are compound heterozygotes. These patients have a GAA expansion on one allele and a point mutation on the other and have been reported to have an atypical phenotype.
  
  
  OBJECTIVE
  To describe a novel dinucleotide deletion in the FRDA gene in two Malaysian siblings with FRDA1.
  
  
  METHODS
  Tertiary referral university hospital setting.
  
  
  METHODS
  A previously healthy 10-year-old Malaysian boy, presented with fever, lethargy, headaches, dysarthria, dysphagia, vertigo and ataxia which developed over a one week period. His neurological exam revealed evidence of dysarthria and ataxia, mild generalized weakness and choreoform movements of the tongue and hands. His reflexes were absent and Babinski sign was present bilaterally. A nine-year-old sister was found to have mild ataxia but was otherwise neurologically intact.
  
  
  RESULTS
  Molecular genetic studies demonstrated that both siblings were compound heterozygotes with a GAA expansion on one allele and a novel dinucleotide deletion on the other allele.
  
  
  CONCLUSIONS
  We describe a novel dinucleotide deletion in the first exon of the FRDA gene in two siblings with FRDA1. Additionally this is the first report of FRDA1 occurring in a family of southeast Asian descent, it demonstrates intrafamilial phenotypic variability, and confirms that atypical phenotypes are associated with compound heterozygosity.
authors.affiliation: Division of Neurology, Biotechnology Laboratory, Brain Research Center, University of British Columbia, Canada.
authors.forename: Siân D
authors.initials: SD
authors.lastname: Spacey
authors.forename: Blazej I
authors.initials: BI
authors.lastname: Szczygielski
authors.forename: Sean P
authors.initials: SP
authors.lastname: Young
authors.forename: Juliette
authors.initials: J
authors.lastname: Hukin
authors.forename: Kathy
authors.initials: K
authors.lastname: Selby
authors.forename: Terrance P
authors.initials: TP
authors.lastname: Snutch
mesh_terms: D002648:Child; D002819:Chorea / Q000235:genetics*; D005260:Female; D005621:Friedreich Ataxia / Q000235:genetics*; D017353:Gene Deletion; D006801:Humans; D033862:Iron-Binding Proteins / Q000235:genetics*; D008296:Malaysia; D008297:Male; D010375:Pedigree; D035781:Siblings; D000096923:Frataxin
chemical_list: D033862:Iron-Binding Proteins; D000096923:Frataxin