Defects of FGFR2 can result in Mendelian diseases involving abnormal bone development, such as Crouzon syndrome [MIM:123500], Jackson-Weiss syndrome [MIM:123150], Apert syndrome [MIM:101200], Pfeiffer syndrome [MIM:101600] and Bent bone dysplasia syndrome [MIM:614592]11, 12, 15. This evidence concerns the gene FGFR2 and bent bone dysplasia syndrome 1.