Abnormal gross appearance and histology of Fgfr2+/P253Rmice. A-D) Alizarin red S and Alcian blue staining of the skull shows domed-shaped skulls with shortened anterioposterior length, short nasal snouts and upper jaw in mutant; I, J) Alizarin red S and Alcian blue staining of the chest shows abnormal bony fusion of sternum (white arrow) in mutant. E-H) Palate abnormalities: (E, F) Superior view shows a defect located at the junction between the primary and secondary palate in mutant (arrow). (G, H) Histology shows incomplete fusion in mutant (arrows). (K, L) Abnormal chondro-osseous transition at the physis in mutant (brackets). Panels A, C, E, G, I, and K are from littermate controls. Panels B, D, F, H, J, and L are the corresponding organs and tissues in mutant mice. (Scale bars: I-P = 50 μm).