The Clinical Spectrum of Familial Hemiplegic Migraine Associated with Mutations in a Neuronal Calcium Channel

Familial hemiplegic migraine is an autosomal dominant disorder. It features attacks of transient hemiparesis followed by migraine headaches. This condition divides into two categories. Pure familial hemiplegic migraine affects 80% of families. The other type involves permanent cerebellar signs and affects 20% of families. Mutations in the CACNA1A gene are found in 50% of families. These mutations are linked to hemiplegic migraine cases, especially with cerebellar signs. Researchers studied the clinical manifestations of CACNA1A mutations in hemiplegic migraine families. They found nine mutations in 15 of 16 probands with cerebellar signs. Two of three subjects with sporadic hemiplegic migraine also had these mutations. Additionally, four of 12 probands with pure hemiplegic migraine had mutations. A total of 117 subjects were identified with mutations. Variability in clinical manifestations is associated with different mutation types. About 89% of subjects experienced hemiplegic migraine attacks. Clinical relevance: This research highlights the broad clinical spectrum of familial hemiplegic migraine, potentially guiding better diagnosis and treatment strategies.