Figure 3. Equivalence of biologic responses induced in the mouse uterus by E₂ (E), GEN (G), and DES (D). (A) Blotted uterine weights (mean ± SD) of three independent replicate groups (1–3) of sexually immature mice (n = 4/group) after three daily subcutaneous injections of either GEN (50 mg/kg), E₂ (2.5 μg/kg), DES (2 μg/kg), or AO [control (C); 5 mL/kg]. (B) Unsupervised Euclidean-distance–based hierarchical clustering of 4,134 expressed genes. (C) Near-identical gene expression profiles induced by the three estrogens 72 hr after equipotent uterotrophic doses. Significant changes in gene expression induced by one or more of the three estrogens were identified by one-way ANOVA (parametric test, assuming equal variance). The magnitude of altered gene expression (fold change vs. vehicle control) is indicated by color.