FGFR1 (fibroblast growth factor receptor 1) is a member of the fibroblast growth factor receptor family containing an Ig-like domain and a tyrosine kinase domain. This receptor has multiple isoforms and is a Type I membrane protein. FGFR1 is a widely expressed membrane receptor, with distinct isoforms expressed in specific tissues. FGFR1 binds fibroblast growth factor and induces mitogenesis and cellular differentiation. Defects in FGFR1 result in Pfeiffer syndrome associated with craniosynostosis. FGFR1 can be modified by phosphorylation and can bind basic/acidic fibroblast factor depending on the receptor isoform. FGFR1 has been shown to interact with N-cadherin and NCAM.