Spinocerebellar ataxia type 10 (SCA10) is a subtype of type I autosomal dominant cerebellar ataxia (ADCA type I; see this term). It is characterized by slowly progressive cerebellar syndrome and epilepsy, sometimes mild pyramidal signs, peripheral neuropathy and neuropsychological disturbances.
Prevalence is unknown. Many kindreds have been found in Mexican and Brazilian populations. SCA10 is the second most common inherited ataxia in these two countries.
Age of onset ranges from 18 to 45 years (mean age = 32.2 years). The most common type of epilepsy is generalized motor seizures, but partial motor or partial complex seizures can occur.
SCA10 is caused by an ATTCT pentanucleotide repeat expansion in intron 9 of the ATXN10 gene (22q13). Exact pathogenesis has not been determined but RNA processing may be involved.
Prognosis is poor, especially for patients with refractory epilepsy. Exact disease duration is unknown. However, the mean disease duration can be estimated to be about 13 years.