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GTR Home > Conditions/Phenotypes > Spinocerebellar ataxia type 17


Excerpted from the GeneReview: Spinocerebellar Ataxia Type 17
Spinocerebellar ataxia type 17 (SCA17) is characterized by ataxia, dementia, and involuntary movements, including chorea and dystonia. Psychiatric symptoms, pyramidal signs, and rigidity are common. The age of onset ranges from three to 55 years. Individuals with full-penetrance alleles develop neurologic and/or psychiatric symptoms by age 50 years. Ataxia and psychiatric abnormalities are frequently the initial findings, followed by involuntary movement, parkinsonism, dementia, and pyramidal signs. Brain MRI shows variable atrophy of the cerebrum, brain stem, and cerebellum. The clinical features correlate with the length of the polyglutamine expansion but are not absolutely predictive of the clinical course.

Genes See tests for all associated and related genes

  • Also known as: GTF2D, GTF2D1, HDL4, SCA17, TBP1, TFIID, TBP
    Summary: TATA-box binding protein

Clinical features


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Practice guidelines

  • EFNS/ENS, 2014
    EFNS/ENS Consensus on the diagnosis and management of chronic ataxias in adulthood.
  • EFNS, 2010
    EFNS guidelines on the molecular diagnosis of ataxias and spastic paraplegias.

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