Micro-CT of the skulls of Fgfr2+/P253Rmice and wild-type littermates. A-D) Mutant skull is shorter in the rostro-caudal, maxilla, and mandible lengths than those of the wild-type controls. In the mutants, the zygomatic process of the maxilla and the malar bone are fused (B, D; white arrows) and unilateral or bilateral coronal synostosis occurs (B, D; black arrows). E, F) The developing mutant palates are shorter than the wild-type. In the mutants, the inter-premaxillary suture is patent (F; white arrow) with fusion of the premaxilla-maxillary sutures (F; black arrow). The suture between the horizontal plate of the palatine bone and palatal process of the maxilla is patent in Fgfr2+/P253Rand wild-type (F; red arrow) but partially fused in Fgfr2+/S252Wmice (not shown). The midline suture between the palatal shelves of the maxilla are patent in mutant mice as well as in some controls (F; blue arrow). Portions of the maxilla were darkened in Photoshop to allow observation of the fusion of the zygomatic process. Panels A, C, and E are from littermate controls. Panels B, D, and F are from Fgfr2+/P253Rmice.