Gnathodiaphyseal dysplasia (GDD) is an autosomal dominant generalized skeletal syndrome characterized by cementoosseous lesions of the jawbones, in conjunction with bone fragility, bowing/cortical thickening of tubular bones, and diaphyseal sclerosis of long bones (summary by Marconi et al., 2013).

Diaphyseal medullary stenosis with malignant fibrous histiocytoma is an autosomal dominant bone dysplasia characterized by pathologic fractures due to abnormal cortical growth and diaphyseal medullary stenosis. The fractures heal poorly, and there is progressive bowing of the lower extremities. In 2 families, affected individuals also showed a limb-girdle myopathy, with muscle weakness and atrophy. Approximately 35% of affected individuals develop an aggressive form of bone sarcoma consistent with malignant fibrous histiocytoma or osteosarcoma. Thus, the disorder may be considered a tumor predisposition syndrome (summary by Camacho-Vanegas et al., 2012).