IKZF1 and hyperinsulinemic hypoglycemia, familial, 4: This systematic review evaluated 90 patients with IKAROS deficiency bearing 28 distinct IKZF1 variants: 66 patients (20 variants) with IKAROS HI, including large deletion and early truncation; 16 patients (6 variants) with IKAROS DD; and 8 patients (two variants) with IKAROS DN (Table 1).