Familial occurrence of arteriovenous malformation of the brain.

Brain arteriovenous malformations are considered to originate from a congenital maldevelopment of the brain vessels. Although there have been occasional reports suggesting a familial incidence of these lesions, data for only 10 families have been accumulated in the literature. The authors report on six such cases in three families. This high rate of occurrence of familial cases suggests an involvement of genetic factors.