Crouzon syndrome was described in 1912 as one of the varieties of craniofacial dysostosis caused by premature obliteration and ossification of two or more sutures, most often coronal and sagittal. [1, 2, 3, 4] Virchow introduced the term craniostenosis.  The type of obliterated sutures determines the type of craniostenosis. Oxycephaly, scaphocephaly, wedge skull, and oblique head are differentiated. [1, 3, 4, 5] Crouzon syndrome with oxycephaly and Apert syndrome with oxycephaly and syndactylia (acrocephalosyndactyly) are the most common cases of dysostosis. Some authors connect those syndromes as one, calling it Crouzon-Apert syndrome, but symptomatologic differentiation makes classification difficult. Acanthosis nigricans (shown in the image below) is the main dermatologic manifestation of Crouzon syndrome (see Acanthosis Nigricans). [3, 4, 6, 7]
Dysplasias of the skeleton (including craniofacial dysostosis) are caused by the malformations of the mesenchyme and ectoderm. The unknown teratogenic factors are taken into account. Dysplasias are inherited in an autosomal dominant pattern. Mutation of the gene (locus 10q26) for fibroblast growth factor receptor 2 (FGFR2) could be responsible for Crouzon syndrome. Moreover, the mutation in the transmembrane region of FGFR3 (locus 4p16.3) was detected in this syndrome and was observed in cases with acanthosis nigricans coexistence. [2, 8, 9, 10, 11, 12, 13, 14]
Race is not noted as a predisposing factor. 
Sex factor does not play any role.