IKZF1 and infection: Eight out of 29 patients had an adult-onset phenotype (19-57 years, all had infections as presenting symptom) and most of them (n=6) were reported within one family with a 4.7 Mb deletion including IKZF1 on chromosome 7 (in contrast to other families with missense mutations or a very small deletion within the IKZF1 gene).