FGFR1 and Pfeiffer syndrome: Mutations in Fgfr2 cause Apert, Crouzon, Jackson-Weiss, and Pfeiffer craniosynostosis syndromes, while mutations in Fgfr1 cause Pfeiffer syndrome and mutations in Fgfr3 cause Muenke craniosynostosis syndrome and Crouzon syndrome with acanthosis nigricans [13–17].