As uncomplicated and attractive as that theory was, it still did not account for the carcinogenicity of TCDD, a non-genotoxic AHR ligand, or for the AHR-driven induction of a growing list of genes unrelated to chemical metabolism but clearly related to cancer (see Section 6.1, Section 6.2, Section 6.3 and Section 6.4). The gene discussed is AHR; the disease is cancer.