This syndrome is named after Octave Crouzon, a French physician who first described this disorder. First called "craniofacial dysostosis" ("craniofacial" refers to the skull and face, and "dysostosis" refers to malformation of bone), the disorder was characterized by a number of clinical features which can be described by the rudimentary meanings of its former name. This syndrome is caused by a mutation in the fibroblast growth factor receptor 2 ("FGFR2"), located on chromosome 10. The developing fetus's skull and facial bones fuse early or are unable to expand. Thus, normal bone growth cannot occur. Fusion of different sutures leads to abnormal patterns of growth of the skull.