Phenotypic characterization of Fam210a+/− mice. (A) Serum calcium (Ca) and phosphorus (P) in Ct (female, n = 9; male, n = 7) and Fam210a+/− (female, n = 8; male; n = 8) mice, and the level of Fam210a protein in serum and muscle extracts of Ct (n = 5) and Fam210a+/− (n = 5) mice using ELISA. Undetectable levels were less than 0.3 ng/mL. (B) BMD and BMC of Ct (female, n = 9; male, n = 9) and Fam210a+/− (female, n = 10; male, n = 9) mouse bones. (C) Parameters of biomechanical bone strength, i.e., the maximal load, stiffness, and work-to-failure, measured by three-point bending tests, in Ct (female, n = 14; male, n = 11) and Fam210a+/− (female, n = 11; male, n = 12) mouse femurs. (D) Representative 3D reconstructions of μCT images of trabecular and cortical bone in Ct (n = 3) and Fam210a+/− (n = 3) mouse femurs. (E) Representative micrographs of double calcein-labeled sections of trabecular and cortical bone of Ct and Fam210a+/− mice; MAR and BFR in trabecular and cortical bone of Ct (n = 4) and Fam210a+/− (n = 4) mice calculated using calcein double labeling. (F) Oc.N/BS and Oc.S/BS in trabecular and cortical bone of Ct (trabecular bone, n = 8; cortical bone, n = 10) and Fam210a+/− (trabecular bone, n = 8; cortical bone, n = 9) mice using TRAP staining. (G) Grip strength in Ct (female, n = 5; male, n = 5) and Fam210a+/− (female, n = 5; male, n = 5) mice; lean mass of all limbs in Ct (female; n = 4, male; n = 4) and Fam210a+/− (female, n = 5; male, n = 4). Solid bars indicate values in Ct, and hatched bars indicate values in Fam210a+/− mice. Data represent mean ± SEM. *P < 0.05; **P < 0.01; ***P < 0.001 using a two-sided Student’s t test. Analyses were performed at 56 d of age.