Trigonocephaly 1, also known as metopic craniosynostosis, is related to non-syndromic metopic craniosynostosis and non-syndromic bicoronal and metopic craniosynostosis. An important gene associated with Trigonocephaly 1 is FGFR1 (Fibroblast Growth Factor Receptor 1). Affiliated tissues include bone and skin, and related phenotypes are wide nasal bridge and delayed speech and language development