As shown in Fig. 3a–c, OCN gene (Bglap) expression and circulating levels of total and unOCN were significantly reduced in Rptorob+/− and Rptorob−/− mice compared to controls (consistent with the previously reported osteopenia observed in these mice14), suggesting that OCN is unlikely to be mediating the metabolic improvements observed in Rptorob−/− mice. Here, BGLAP is linked to Osteopenia.