The basal level of alveolar bone volume without ligature was lower in Sh3bp2KI/+ mice (Fig. 1E; unligated), which is consistent with our previous report that Sh3bp2KI/+ mice exhibit osteopenia in long bones because of increased osteoclast formation.2 Induction of periodontitis further decreased the alveolar bone volume in Sh3bp2KI/+ and Sh3bp2+/+ mice (Fig. 1E; ligated) and the percentage of alveolar bone loss in the ligated side compared with the unligated side (susceptibility to bone loss) was higher in Sh3bp2KI/+ mice (Fig. 1F). This evidence concerns the gene SH3BP2 and periodontitis.