Among those dissimilarly expressed in patients and healthy subjects, cluster 1 includes all those KCTDs (KCTD1, KCTD2, KCTD7, KCTD9, KCTD11, KCTD17, and KCTD21) whose expression, although scattered among samples, is increased in T-ALL patients. Here, KCTD21 is linked to acute lymphoblastic leukemia.