1. ¹Department of Medicine (Neurology and Rheumatology), Shinshu University School of Medicine, Matsumoto, Japan
2. ²Department of Neurology, Hokushin General Hospital, Nakano, Japan
3. ³Department of Neurology, Tokyo Women's Medical University, Shinjuku, Japan

Correspondence: Dr K Yoshida, Department of Medicine (Neurology and Rheumatology), Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan. E-mail: kyoshida@shinshu-u.ac.jp

Received 3 June 2009; Revised 29 August 2009; Accepted 23 September 2009; Published online 6 November 2009.

Abstract

We report a 67-year-old Japanese woman with ataxia with oculomotor apraxia type 2 (AOA2). She was born to consanguineous parents and showed a teenage onset, a slowly progressive cerebellar ataxia and sensory-motor neuropathy and an elevated level of serum -fetoprotein (AFP). All of these clinical features were consistent with typical AOA2. She lacked oculomotor apraxia, as frequently observed in previously reported AOA2 patients. She was homozygous for a novel nonsense mutation, Glu385Ter (E385X), in the senataxin gene (SETX). To our knowledge, this is the fifth Japanese family with genetically confirmed AOA2. The mutations in SETX in Japanese AOA2 families are heterogeneous, except for M274I, which has been found in two unrelated families. More extensive screening by serum AFP followed by molecular genetic analysis of SETX in patients with Friedreich's ataxia-like phenotype may show that AOA2 is more common in Japan than previously thought.