Immunologic disturbances in mice fed by mothers with an induced graft versus host reaction

: The carcinogenic polycyclic aromatic hydrocarbons have been shown to induce frameshift mutations rather than base-pair substitutions in Ames test strains devoid of pKM101 plasmid. This plasmid enhances the frequency of induced frameshift mutations and mediates the induction of base-pair substitutions during the action of these carcinogens. No correlation was observed between the degree of mutagenesis induced in plasmid-containing and in plasmid-free strains by the test agents and their reported carcinogenic activity.