IHH and craniosynostosis: That said, IHH positively regulates intramembranous osteogenesis with IHH duplications resulting in an overexpression of IHH being associated with craniosynostosis, and Ihh−/− mice exhibiting small calvarial bones with expanded sutures (Figures 3E–H) (Klopocki et al., 2011; Lenton et al., 2011).