What causes craniosynostosis?

Sutures close: Premature closing of the sutures of the cranium.

Craniosynostosis: Most cases of craniosynostosis occur spontaneous with no previous family history. There are known genetic conditions in which it can occur and there are some environmental factors, mostly medications taken during pregnancy that can cause craniosynostosis. In my practice, if you take away the syndromic children most of the cases are a first time occurence with no family history

Premature Fusion: of the cranial sutures is responsible for craniosynostosis. Multiple genes have been implicated: FGFRs, TWIST, MSX2, etc, Over half of the single suture cases have no obvious genetic cause, indicating environmental and epigenetic causes contribute to abnormal fusion.