Genetic heterogeneity of autosomal dominant nonprogressive congenital ataxia.

We studied a family with nonprogressive congenital ataxia (NPCA) previously reported in 1985. Follow-up evaluation documented a nonprogressive course. Older family members developed ataxic spells and vertical oscillopsia triggered by stress and exercise. Linkage analysis using a 10K single-nucleotide polymorphism array found suggestive linkage to four loci on chromosomes 1q44, 5q35.1-35.3, 7q36.2-36.3, and 9q31.2-32 and ruled out linkage to the NPCA locus on 3p, proving genetic heterogeneity for autosomal dominant NPCA.