Osteogenic induction in hereditary disorders of heterotopic ossification

The formation of heterotopic bone within soft connective tissue is a common feature of at least three distinct genetic disorders of osteogenesis in hu mans: fibrodysplasia ossificans progressiva; progressive osseous heteroplas ia; and Albright hereditary osteodystrophy. The pathobiologic characteristi cs of osteogenic induction, the histopathologic features of osteogenesis, t he anatomic distribution of heterotopic lesions, and the developmental patt erns of disease progression differ among all three conditions. The molecula r and cellular basis of redirecting a mature connective tissue phenotype to form bone is a remarkable biological phenomenon with enormous implications for the control of bone regeneration, fracture healing, and disorders of o steogenesis.