We searched for mutations in the voltage-gated calcium channel gene, C
ACNA1A in nine propositi of families with migraine headaches and episo
dic vertigo inherited in an autosomal dominant pattern. All 47 exons a
nd flanking introns in CACNA1A were subjected to single-strand conform
ation polymorphism analysis of polymerase chain reaction-amplified gen
omic DNA. Exons with aberrantly migrating fragments were sequenced usi
ng standard techniques. We also determined the CAG repeat length at th
e 3' end of CACNA1A. Several polymorphisms were found but no mutations
identified in any of the 47 exons of the 9 patients. No index-case ha
d a CAG repeat length greater than 13 (normal <17). Mutations in CACNA
1A are not common in families with migraine headaches and episodic ver
tigo. Other ion channel genes expressed in the brain and inner ear rem
ain candidate genes. Am. J. Med. Genet. 79:148-151, 1998. (C) 1998 Wil
ey-Liss, Inc.