This type of craniosynostosis is caused by mutations in the fibroblast growth factor receptor-2 gene, FGFR2, located at 10q26. It is generally considered an autosomal dominant disorder based on familial cases but most occur sporadically. A paternal age effect on mutations has been found.
The same gene is mutant in other craniosynostosis disorders sometimes clinically separated such as Pfeiffer Syndrome (101600), Jackson-Weiss syndrome (123150), Beare-Stevenson Syndrome (123790), Apert Syndrome (101200), and Saethre-Chotzen Syndrome (101400). However, this entire group has many overlapping features making classification on clinical grounds alone difficult. Only Apert syndrome (101200) is caused by a unique mutation whereas other syndromes seem to owe their existence to multiple mutations.