FGF9 and craniosynostosis: With this report, we confirm the association of craniosynostoses with pathogenic variants in FGF9 by describing the second family with at least one affected individual with craniosynostosis associated with SYNS3, after that of Rodriguez-Zabala et al. The authors performed extensive analyses, including proximity ligation assays, to compare the degree of homodimerization between the wild type and FGF9 mutations and concluded that the mutation in FGF9 is responsible for the craniosynostoses [11].