The cumulative incidences of hypogammaglobulinemia and AD are 67%-86% and 3%-33% in IKAROS deficiency and 20%-71% and 61%-86% in CTLA4 deficiency, respectively (3, 4, 7, 8, 23). The gene discussed is IKZF1; the disease is hyperinsulinemic hypoglycemia, familial, 4.