In the presence of colitis, octn1-/- microbiome displayed a higher representation of metabolic pathways (degradation of glycan, glycosaminoglycan, and 1,1,1-Trichloro-2,2-bis [4-chlorophenyl] ethane [DDT]; metabolism of galactose, nitrogen, sphingolipid, cyano-amino acid, and pyruvate; biosynthesis of lipopolysaccharide) and of inorganic ion transport, metabolism, and restriction enzymes. Here, SLC22A4 is linked to colitis.