FGFR3 and craniosynostosis: FGF23 can bind to both FGFR2 and FGFR3, and it has been suggested that FGF23 can cross‐bind FGFR2 and FGFR3 at the cranial sutures, causing premature fusion.(20) This is consistent with the role of mutations in FGFR2 and FGFR3 in congenital craniosynostosis.