To test our hypothesis that development of diet-dependent obesity in Nod2−/− mice increases sensitivity to liver cancer, we treated WT and Nod2−/− 4–5 day old pups one-time with the carcinogen dimethylbenz[a]anthracene (DMBA) and 3 days later placed their nursing mothers on HFD. The gene discussed is NOD2; the disease is obesity due to melanocortin 4 receptor deficiency.