1The Department of Orthopaedic Surgery, The Perelman School of Medicine of The University of Pennsylvania, Philadelphia, PA 19104, United States of America
2The Department of Medicine, The Perelman School of Medicine of The University of Pennsylvania, Philadelphia, PA 19104, United States of America
3The Center for Research in FOP & Related Disorders, The Perelman School of Medicine of The University of Pennsylvania, Philadelphia, PA 19104, United States of America
4The Division of Oncology, Department of Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, United States of America
5The Department of Pediatrics, Division of Hematology-Oncology, University of Rochester School of Medicine, Rochester, NY 14642, United States of America
6Division of Pediatric Rheumatology, Department of Pediatrics, University of Rochester School of Medicine, Rochester, NY 14642, United States of America
7The Department of Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, PA, United States of America
8The Division of Endocrinology and Metabolism, the UCSF Metabolic Bone Clinic, the Institute for Human Genetics, University of California-San Francisco, San Francisco, CA, United States of America
9The Division of Biostatistics, Department of Biomedical Engineering, University of California – Davis, Davis, CA, United States of America
10The Department of Medicine, The Mayo Clinic, Rochester, MN 55905, United States of America