DMP1 and Osteopenia: In terminally differentiated osteocytes, expressing dentin matrix acidic phosphoprotein 1 (DMP-1), Windahl et al. showed that deletion of ERα decreased trabecular BV/TV exclusively in male mice [87] whilst in contrast, Kondoh et al. showed that osteocytic deletion of ERα led to trabecular osteopenia in female but not male mice [88].