The spectrum of frontonasal dysplasia in an inbred pedigree.

An inbred pedigree is described in which three members were affected with FND (Frontonasal Dysplasia). Two of these individuals were products of a consanguineous mating with an inbreeding coefficient of F = 0.0391. The third affected individual (propositus), was born to a marriage in which the coefficient of inbreeding was 0.0742. The mother of the propositus, whose inbreeding coefficient was 0.0625, had borderline hypertelorism and a broad nose. Several other members of the pedigree who had hypertelorism were products of consanguineous matings. The presence of consanguinity in all individuals affected with a variety of manifestations of FND suggests a genetic mechanism for this malformation.