Crebbp^+/− mice have decreased bone volume. (A) Representative histological sections of tibiae and femurs stained with H&E from 3- to 4-month-old wild-type (Wt) and Crebbp^+/− mice (BX41 microscope; Olympus DP71 Digital Imaging System) at a magnification of 1.25×. (B) Representative radiographic images and (C) microCT 2D slices of tibiae from the same groups of mice. (D-G) MicroCT measurements in the proximal tibia for BV/TV (*P = .007) (D), trabecular number per cubic millimeter (*P = .003) (E), trabecular thickness in millimeters (*P = .044) and separation between trabeculae in millimeters (*P = .028) (F), and cortical bone thickness in millimeters (*P = .0007) (G). (D-G) Data represent means ± SEM (n = 3-5) from 3- to 4-month-old Wt and Crebbp^+/− mice. (H) Representative images of CFU-Fs produced from Wt and Crebbp^+/− BM and the average number ± SEM of CFU-Fs per 3 × 10⁶ BM cells (n = 3). For each experiment, BM from 3 mice was combined (*P = .031). (I) Average number ± SEM of osteoclasts produced by 1 × 10⁶ Wt and Crebbp^+/− BM cells (n = 5; P = .031). (J) Number of osteoclasts per millimeter of bone surface in Wt and Crebbp^+/− mice (n = 3-5 mice; P = .058).