Familial occurrence of migraine without aura and migraine with aura

We report a study of 121 probands (patients) with migraine without aura (MO) and 72 probands with migraine with aura (MA), diagnosed according to the operational diagnostic criteria of the International Headache Society and selected from 35 general practices in Denmark. The probands were interviewed about the presence of MO and MA among their first-degree relatives. Compared with the general population, the first-degree relatives of probands with MO had a threefold increase of MO, and only one first-degree relative of one proband with MO had MA. First-degree relatives of probands with MA had a twofold increase of both MA and MO. Compared with the general population, few spouses had MO and MA. This threefold and twofold increase in family risk of MO and MA, combined with the lack of increased risk in spouses, strongly suggests that MO and MA are genetically determined.