When analysing colitis secondary to anti-CTLA-4 treatment, there were differences between subjects prone and resistant to colitis: a higher abundance of bacteria from the Bacteroidetes phylum, specifically from Bacteroidaceae, Rikenellaceae, and Barnesiellaceae families, was observed in patients who did not manifest adverse events (Panebianco et al., 2018). The gene discussed is CTLA4; the disease is colitis.