ERF and craniosynostosis: There is an interaction between FGFR and RAS/MAPK signaling pathways, as demonstrated by experiments in an FGFR mouse model where craniosynostosis is rescued using an inhibitor of RAS/MAPK signaling and by the fact that mutations in ERF (ETS2 repressor factor, *611888, a gene at the end of the FGFR-RAS/MAPK cascade) also cause craniosynostosis (Shukla et al., 2007; Takenouchi et al., 2014; Addissie et al., 2015).