Kif3aOc-cKO mice developed osteoporosis at 6 weeks of age, as evidenced by reduced femoral mineral density, trabecular volume, and cortical thickness. Shh-mediated expression of Gli2 as well as Wnt3a-mediated expression of β-catenin and Axin2 were attenuated. This evidence concerns the gene AXIN2 and osteoporosis.