TCF7L2 and hyperinsulinemic hypoglycemia, familial, 4: Interestingly, nine have been implicated in GI disorders; for example, Nfil3 deficiency has been associated with colitis, NFIL3 is a susceptibility gene for inflammatory bowel disease,40, 41 and TCF7L2 has been implicated in colorectal cancer.42, 43