Familial microtia in four generations with variable expressivity and incomplete penetrance in association with type I syndactyly.

Familial microtia with external ear canal atresia and conductive deafness is rarely reported. Autosomal dominant and recessive inheritance have been suggested depending on various family reports. Cases with other malformations in addition to microtia have been described, although the microtia generally is an isolated finding. Here we report a family with microtia, external auditory canal atresia and conductive deafness in four generations. The mode of inheritance of the disease was autosomal dominant within this family. Also, variable expressivity, incomplete penetrance and generation skipping are evident in the pedigree. Association of microtia with type I syndactyly, which has never been reported previously, was present in the index case.