The pleiotropic effects of fibroblast growth factor receptors in mammaliandevelopment

In recent years the study of fibroblast growth factor receptors (FGFRs) in normal development and human genetic disorders has increased our understand ing of some complex cellular processes. At least fifteen genetic disorders result fi om mutations within FGFR genes including skeletal dysplasias such as Apert syndrome and achondroplasia, In vitro experiments and the generat ion of animal models indicate that these mutations result in activation of the receptors and that FGFRs act as negative regulators of hone growth, FGF Rs also play a role in wound healing and cancer. In this article, we review the expression of FGFRs in human development, the phenotypes resulting fro m FGFR mutations, and recent data identifying pathways downstream of the ac tivated receptors.