Loss of heterozygosity in spontaneous and chemically induced tumors of the B6C3F1 mouse

The B6C3F1 mouse is used worldwide to gauge the carcinogenic hazard posed by chemicals to human. An assessment of the ability of this rodent model to predict human neoplasia requires an evaluation of similarities and differences in the genetics of tumor formation between these two species. We isolated 142 spontaneous and chemically-induced liver tumors isolated from the B6C3F1 mouse for losses of heterozygosity (LOH) at 78 polymorphic loci and compared these results to genetic changes known to occur in human hepatocellular carcinoma. Approximately a third of the 142 mouse tumors exhibited LOH, suggesting that tumor suppressor gene inactivation may be involved in the formation of mouse liver tumors