Abstract
Diethylstilbestrol diphosphate (DES‐dp) clastogenesis was examined in the bone marrow of C57B1/6 male and female mice. Significant and sex‐related dose effects were observed for the induction of chromatid‐type chromosomal aberrations and for the inhibition of cellular proliferation. Females were more sensitive to the effects of DES‐dp than males when assessed for either induced chromosomal aberrations or proliferative inhibition. Contrary to other published results, we did not observe either an increase in sister chromatid exchanges or an increased incidence of aneuploidy. Ovariectomy reduced the ability of DES‐dp to inhibit cellular proliferation and decreased the high degree of variability between animals at high doses of DES‐dp. The results of our studies show that DES is a clastogenic agent in vivo which may relate to its carcinogenicity.