Spinocerebellar ataxia type 6 with positional vertigo and acetazolamide responsive episodic ataxia
- aDepartment of Neurology, bDepartment of Pediatrics/Hematology and Oncology, cDepartment of Surgery (Head and Neck), UCLA School of Medicine, Los Angeles, California, USA
- Dr Robert W Baloh, UCLA Department of Neurology, Box 951769, Los Angeles, CA 90095–1769, USA. Telephone 001 310 825 5910; fax 001 310 206 1513; email:
- Received 18 December 1997
- Revised 9 March 1998
- Accepted 19 March 1998
The SCA6 mutation, a small expansion of a CAG repeat in a calcium channel gene CACNA1A, was identified in three pedigrees. Point mutations in other parts of the gene CACNA1A were excluded and new clinical features of SCA6 reported—namely, central positional nystagmus and episodic ataxia responsive to acetazolamide. The three allelic disorders, episodic ataxia type 2, familial hemiplegic migraine, and SCA6, have overlapping clinical features.