ANALYSIS OF 31 FAMILIES WITH AN APPARENTLY AUTOSOMAL-DOMINANT TRANSMISSION OF MIGRAINE WITH AURA IN THE NUCLEAR FAMILY

We analyzed 31 families selected for an apparently autosomal-dominant mode of inheritance of migraine with aura (MA) in the nuclear family, The nuclear families were expanded with first- and second-degree relat ives. All interviews were made by physicians experienced in headache d iagnoses. The criteria of the International Headache Society were used , The population relative risk among children in nuclear families was similar to the estimated population relative risk of MA assuming an au tosomal-dominant mode of inheritance, The population relative risk ten ded to decrease among first-degree relatives outside nuclear families and further among second-degree relatives. Both first- and second-degr ee relatives outside the nuclear families had a statistically signific ant lower risk of MA than expected. Thus, autosomal-dominant inheritan ce with or without reduced penetrance was unlikely, Autosomal-recessiv e inheritance was unlikely because of the unequal sex distribution, Ot her modes of inheritance were considered as well. Mitochondrial and X- linked inheritance were excluded because of paternal transmission. The female preponderance was too low to explain sex-influenced inheritanc e. We conclude that MA most likely has a multifactorial inheritance ev en in high-risk families with MA. (C) 1997 Wiley-Liss, Inc.