Compared to healthy, untreated control subjects, the authors found that male T2DM patients under TZDs treatment experienced an increase of 11 and 16.8% in s-sclerostin and s-CTX levels, respectively, contrary to the metformin-treated group, which did not show any significant changes in s-sclerostin but had a 19% decrease in s-CTX (53). The gene discussed is CYP27A1; the disease is type 2 diabetes mellitus.