Multigenerational effects of dietary fat carcinogenesis in mice.

The possibility of multigenerational transmission of a carcinogenic effect from exposure to a maternal diet high in fat was tested in mice. Diets with 2.6 or 29% fat (by weight) were fed to strain CD-1 mice during pregnancy. The female offspring were raised on a control diet (10% fat), mated, and continued on the control diet through pregnancy. Their female offspring were raised to terminal illness and autopsied. The total number of reproductive system tumors, pituitary tumors, and metastases was increased in the offspring with ancestral exposure to high dietary fat but to a lesser extent than had been reported previously for direct prenatal exposure to high maternal dietary fat. Because previous work has given evidence against germ cell transmission, a hypothesis based on a maternal effect was offered to explain the multigenerational carcinogenesis. These results have implications for epidemiological studies.