It is clear from this study that the site of the FGFR3 activating mutation determines the effect on the osteochondral differentiation potential of hPDCs, as PRX1Cre- and FGFR3Y637C+-derived periosteal cells failed to undergo complete endochondral ossification, resulting in pseudoarthrosis and failed fracture repair [32]. The gene discussed is FGFR3; the disease is Pseudoarthrosis.