Parkinson's disease associated with pure repeat expansion.

Large, non-coding pentanucleotide repeat expansions of ATTCT in intron 9 of the gene typically cause progressive spinocerebellar ataxia with or without seizures and present neuropathologically with Purkinje cell loss resulting in symmetrical cerebellar atrophy. These repeat expansions can be interrupted by sequence motifs which have been attributed to seizures and are likely to act as genetic modifiers. We identified a Mexican kindred with multiple affected family members with expansions.