Besides AML, IKZF1N159S hotspot mutations were observed in patients with T‐cell acute lymphoblastic leukemia (T‐ALL)12 and in a combined immunodeficiency syndrome, where germline IKZF1N159S mutations exerted a dominant‐negative effect on IKAROS wild‐type function.8 Here, IKZF1 is linked to acute lymphoblastic leukemia.