The family pedigree across eight generations is presented with an association of osteochondrodysplasia, other skeletal abnormalities, familial glial tumours in a father and his son, colonic and other adenomatous disease, and pigment changes. This family cluster of diseases is considered to be a dysontogenetic process with blastomatous features and grouped within the phakomastoses. A review of the literature indicates that some "familial gliomas" show additional malformations, thus resembling phakomatoses. Others are found to be members within a "familial cancer syndrome". A trait of "hereditary glioma" apart from these syndromes is difficult to identify, especially if only sibships are considered which are likely to share common environmental factors.