title: Non-Ataxic Phenotypes of SCA8 Mimicking Amyotrophic Lateral Sclerosis and Parkinson Disease.
abstract: BACKGROUND
  Spinocerebellar ataxia (SCA) type 8 (SCA8) is an inherited neurodegenerative disorder caused by the expansion of untranslated CTA/CTG triplet repeats on 13q21. The phenomenology of SCA8 is relatively varied when compared to the other types of SCAs and its spectrum is not well established.
  
  
  METHODS
  Two newly detected cases of SCA8 with the nonataxic phenotype and unusual clinical manifestations such as dopaminergic-treatment-responsive parkinsonism and amyotrophic lateral sclerosis (ALS) are described herein. Family A expressed good dopaminergic treatment-responsive parkinsonism as an initial manifestation and developed mild cerebellar ataxia with additional movements, including dystonic gait and unusual oscillatory movement of the trunk, during the disease course. The proband of family B presented as probable ALS with cerebellar atrophy on brain MRI, with a positive family history (a brother with typical cerebellar ataxia) and genetic confirmation for SCA8.
  
  
  CONCLUSIONS
  Our findings support that the non-ataxic phenotypes could be caused by a mutation of the SCA8 locus which might affect neurons other than the cerebellum.
authors.affiliation: Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. ; Department of Neurology, Soonchunhyang University Hospital, Soonchunhyang University School of Medicine, Seoul, Korea.
authors.forename: Ji Sun
authors.initials: JS
authors.lastname: Kim
authors.forename: Tae Ok
authors.initials: TO
authors.lastname: Son
authors.forename: Jinyoung
authors.initials: J
authors.lastname: Youn
authors.forename: Chang-Seok
authors.initials: CS
authors.lastname: Ki
authors.forename: Jin Whan
authors.initials: JW
authors.lastname: Cho
keywords: Amyotrophic lateral sclerosis; Parkinson's disease; Spinocerebellar ataxia 8; clinical heterogeneity; phenotype