FGFR3 and achondroplasia: While FGFR3 gain of function mutations lead to short stature (achondroplasia, ACH, MIM #100800 and hypochondroplasia, HCH, MIM #146000), FGFR3 loss of function mutations cause camptodactyly, tall stature, and hearing loss syndrome (CATSHLS, MIM #610474) (37, 38).