Even though previousstudies have been undertaken to examine the association between CYP1A1 Ile/Val,mEH, and GSTM1 null polymorphisms, as well as oral and pharyngeal cancers, fewinvestigated the modification of risk associated with tobacco and alcoholconsumption, and to our knowledge, this is the first to analyse the gene-geneinteractions between these polymorphisms. This evidence concerns the gene CYP1A1 and pharynx cancer.