Clinical teaching dictates that isolated unicoronal
synostosis is sporadic in occurrence and is possibly related to intrauterine constraint. Despite this, isolated reports document a familial occurrence. It has previously been recognized that there may be a familial pattern of inheritance. Recently, mutations in
fibroblast growth factor receptors (FGFRs) have been implicated in several syndromic
craniosynostoses. At the authors' institution, mutations in FGFR3, located at chromosome 4p16, have been found to cause coronal
synostosis. Two cases of unicoronal
synostosis were found to have the same Pro250Arg missense mutation in FGFR3. This finding suggested that all patients with a diagnosis of unicoronal
synostosis be screened for the FGFR3 mutation. Between January and December of 1996, patients with a diagnosis of
plagiocephaly at the Children's Hospital of Philadelphia were evaluated for the FGFR3 mutation. Thirty-seven patients with unicoronal
synostosis had mutational studies. Two additional patients were known to have the FGFR3 mutation at the onset of the study. Of the 37 patients screened, four were found to have the FGFR3 mutation, for a total of six patients with both unicoronal
synostosis and the FGFR3 mutation. All patients with unicoronal
synostosis were evaluated for facial dysmorphology and operative outcome. The six patients with the FGFR3 mutation had more severe cranial dysmorphology and were more likely to need surgical revision than those without the FGFR3 mutation. The occurrence of the FGFR3 mutation among patients with unicoronal
synostosis provides evidence for a genetic basis of certain forms of
plagiocephaly. The clinical, radiologic, and molecular findings will be an important addition to the surgical management and counseling of patients with unicoronal
synostosis.