The composition of genes necessary for CPS biosynthesis, including transcriptional regulatory elements (UpxY and UpxZ), coding regions for glycosyltransferase genes, UDP-N-acetylglucosamine 2-epimerase (EC 5.1.3.14), and glucosamine-6-phosphate deaminase (EC 3.5.99.6) did not significantly differ among patients or between pouchitis and nonpouchitis patients. Here, CAD is linked to pouchitis.