Skeletal phenotypes of Smpd3flox/flox; Osx-Cre newborn pups. (A) Skeletal analyses were performed on WT, fro/fro, Smpd3flox/flox, and Smpd3flox/flox; Osx-Cre newborn pups. Alizarin red- and alcian blue-stained skeletal preparations show that both Smpd3flox/flox; Osx-Cre and fro/fro mice exhibit similar skeletal phenotypes. (B) Magnified view of skeletal preparations showing the calvaria' forelimbs, and hind limbs of newborn WT, fro/fro, Smpd3flox/flox, and Smpd3flox/flox; Osx-Cre pups.