Furthermore, mutations in the most common genes associated with EA, namely in the CACNA1A gene (associated with EA type 2) and KCNA1 (associated with EA type 1) might lead to different clinical entities without episodes of vertigo/ataxia, such as epilepsy, paroxysmal dyskinesia, or hemiplegic migraine (4, 6, 21, 23). The gene discussed is KCNA1; the disease is familial or sporadic hemiplegic migraine.