Preliminary analyses of patients in the UKALL2003 cohort suggest ETP-ALL patients in this cohort showed some of the genetic characteristics of ETP-ALL (less frequent NOTCH1/FBXW7 mutations, no LMO1/2 or TLX1 mutations, and increased rate of KMT2A translocations). Here, TLX1 is linked to acute lymphoblastic leukemia.