ABC transporters (1.44-fold increase in CDI+ individuals), two-component system (1.85-fold increase in CDI+ individuals), flagellar assembly (5.11-fold increase in CDI+ individuals), phosphotransferase system (1.57-fold increase in CDI+ individuals), and ascorbate and adorate metabolism (3,47-fold increase in CDI+ individuals) were the top five expressed gene pathways identified within the CDI+ cohort. This evidence concerns the gene ABCG2 and clostridium difficile infection.