DE-NOVO MUTATION IN CACNA1A CAUSED ACETAZOLAMIDE-RESPONSIVE EPISODIC ATAXIA

With the recent report of mutations in the calcium channel gene CACNA1 A in two families with episodic ataxia type 2, we investigated a patie nt with nonfamilial episodic vertigo and ataxia responsive to acetazol amide for similar mutations. Single-strand conformation polymorphism ( SSCP) analysis of exon 23 identified an extra band in the patient that was not present in other relatives or in normal controls. Exon 23 of the patient showed a spontaneous C to T substitution at position 4410 resulting in an early stop codon. Patients with nonfamilial episodic a taxia may respond to acetazolamide and may have mutations in CACNA1A. (C) 1998 Wiley-Liss, Inc.