1. Department of Orthopedic Surgery, Perelman School of Medicinethe University of PennsylvaniaPhiladelphiaPAUSA
2. The Center for Research in FOP and Related Disorders, Perelman School of Medicinethe University of PennsylvaniaPhiladelphiaPAUSA
3. The Children's Hospital of PhiladelphiaDivision of Orthopedic SurgeryPhiladelphiaPAUSA
4. Regeneron PharmaceuticalsTarrytownNYUSA
5. Department of Medicine, Perelman School of Medicinethe University of PennsylvaniaPhiladelphiaPAUSA
6. Department of Genetics, Perelman School of Medicinethe University of PennsylvaniaPhiladelphiaPAUSA