The Fgfr2cC342Y/+ Crouzon syndrome mouse model (Eswarakumar et al., 2004) carries a cysteine to tyrosine substitution at amino acid 342 (Cys342Tyr; C342Y) in the protein encoded by Fgfr2c equivalent to the FGFR2 variant common to Pfeiffer and Crouzon syndromes (Eswarakumar et al., 2004; Oldridge et al., 1995; Reardon et al., 1994; Rutland et al., 1995). Here, FGFR2 is linked to Crouzon disease.