The reported incidence of ICI-induced diabetes varies between 0.9 and 2% [28], with a significant proportion of cases, up to 76%, attributed to the use of anti-PD-1 agents, 8% to anti-PD-L1 agents, and only 4% to the use of anti-CTLA-4 agents [7,37]. The gene discussed is CTLA4; the disease is diabetes mellitus.