In HIV-1 infection, AHR activation stimulated by ligand of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or by TCDD chemical homologue 3-methylcholanthrene (3-MC) was previously shown to reactivate HIV-1 from latency (51, –, 54), and induction of AHR and AHR-regulated CYP1A1 enzymes by TCDD was shown to be associated with enhanced activity of HIV RNA-dependent DNA polymerase (Pol) and increased expression of viral protein in human T cells (55). This evidence concerns the gene AHR and HIV-1 infection.