ASXL1^cKOmice have low bone mass. (A-B) Femurs of 13-week-old male ASXL1 ^flox/flox and ASXL1^cKO (ASXL1flox/flox LysM^cre/cre) littermates were subjected to µCT analysis (n = 5 in each group). Scale bar represents 100 μm. (C-D) Femurs of ASXL1^flox/flox and ASXL1^cKO mice (left) stained for TRAP activity (red reaction product). Scale bar represents 1 mm. Histomorphometric analysis of osteoclast number (OcN) per bone surface (BS) and ratio of trabecular bone volume (BV) to total marrow space (total volume [TV]) of ASXL1^flox/flox and ASXL1^cKO mice (n = 5 in each group) quantified using BioQuant software. (E) Serum analysis for TRAP5B in ASXL1^flox/flox and ASXL1^cKO 12-week-old male mice (n = 7 mice in each group). Unpaired nonparametric Student t test was used for statistical analysis. Error bars represent + SD; *P < .05, **P < .01, ***P < .001. BV/TV, bone volume fraction of marrow; Conn-Dens, connectivity density, normed by TV; ns, not significant; TbN, trabecular number; TbSp, trabecular separation; TbTh, trabecular thickness; vBMD, volumetric bone mineral density.