Here, we use hiPSCs from patients with FOP [14] as a model of cell-autonomous signaling induced by the ACVR1 R206H mutation to test if the mutation increases the formation of potential osteoprogenitors in the EC lineage, and if hiPSC-derived endothelial cells (iECs) expressing ACVR1 R206H show increased plasticity towards osteogenesis. This evidence concerns the gene ACVR1 and fibrodysplasia ossificans progressiva.