Sporadic SCA8 mutation resembling corticobasal degeneration.

Spinocerebellar ataxia type 8 (SCA8) is caused by the expansion of CTA/CTG triplet repeats on 13q21. Cases can be familial or sporadic. The clinical findings include cerebellar ataxia with upper motor neuron dysfunction, dysphagia, peripheral sensory disturbances, or cognitive and psychiatric impairments, indicating phenotypic variability in SCA8. We report on a patient with rapidly progressive parkinsonism-plus syndrome resembling corticobasal degeneration and triplet expansions in the SCA8 locus. The relationship between clinical phenotype and triplet expansions in the SCA8 locus requires further study.