A GENE FOR FAMILIAL HEMIPLEGIC MIGRAINE MAPS TO CHROMOSOME-19

Familial hemiplegic migraine is an autosomal dominant disorder of unkn own pathogenesis in which the migrainous attacks are marked by the occ urrence of a transient hemiplegia during the aura, While investigating CADASIL, mapped previously to chromosome 19, we observed that some pa tients had recurrent attacks of migraine with aura. Although the clini cal and neuroimaging features of familial hemiplegic migraine differ m arkedly from CADASIL, we hypothesized that the same gene could be invo lved in the pathogenesis of both conditions. We chose two large pedigr ees for linkage analysis of familial hemiplegic migraine. A maximum lo d score > 8 was found with two markers that are also strongly linked t o CADASIL. Multilocus linkage analysis suggested that the loci respons ible for the two diseases reside within an interval of about 30 cM on chromosome 19.