CISs specific for ETP-ALL affected mature T cell genes (inactivation of Ikzf2, Ikzf3), Ras pathway components (Rapgef2, Nf1), and potential negative regulators of Wnt signaling (Kremen1, Tmem170b; not linked to T-ALL so far). This evidence concerns the gene RAPGEF2 and acute lymphoblastic leukemia.