Spinocerebellar Ataxia Type 3 Phenotypically Resembling Parkinson Disease in a Black Family

Abstract

Parkinsonism suggestive of PD due to MJD/SCA3 has not been previously reported, to our knowledge. However, atypical, though also levodopa-responsive, parkinsonism has been previously reported to occur in African American families, suggesting that that this phenotype is associated with African ancestry. In this regard, it is perhaps significant that all the individuals with parkinsonism have relatively low numbers of repeats (normal, 16-34; pathologic, 60-84). In families in which linkage analysis is being performed to determine a locus for autosomal dominant parkinsonism suggestive of PD, evaluation for the MJD/SCA3 mutation is indicated.