Ataxia with oculomotor apraxia type 1 (AOA1): clinical and neuropsychological features in 2 new patients and differential diagnosis.

Ataxia with oculomotor apraxia type 1 (AOA1) is an autosomal recessive disease characterized by early-onset and slowly progressive cerebellar ataxia, areflexia, and peripheral neuropathy. Ocular apraxia is most prominent in the early stage of the disease, by contrast, hypoalbuminemia, hypercholesterolemia, and cognitive impairment are present in the adult stage. AOA1 is caused by a mutation in the APTX gene (9p13.3) encoding a nuclear protein named aprataxin, which is involved in the mechanism of DNA repair. We report here the clinical features of 2 patients with mutations in the APTX gene, and we discuss the differential diagnosis with other forms of hereditary ataxia.