A rare genetic persistent combined dystonia with characteristics of clinical signs similar to ataxia-telangiectasia but with a later (usually adulthood) onset and slower progression. Patients typically present with extrapyramidal signs, such as resting tremor, choreoathetosis and dystonia, as the initial symptoms and later often develop mild cerebellar ataxia (with gait usually preserved). Telangiectasia and immunodeficiency may be absent but secondary features of ataxia-telangiectasia, such as risk of malignancy, dysarthria and peripheral neuropathy, are frequently present. [from
SNOMEDCT_US]