Germline or somatic mutations of IKZF1 demonstrate quite variable clinical phenotypes, ranging from primary immunodeficiency (PID)/inborn errors of immunity (IEI) (10–12) to autoimmune diseases (13–16) and to even hematological malignancies such as acute lymphoblastic leukemia (17, 18). This evidence concerns the gene IKZF1 and inborn error of immunity.