A presumed diagnosis of BCR-ABL1-like ALL can be enabled using an NGS CNV analysis to test for genetic alterations in IKZF1 and JAK1/JAK2 because the former (68%) and latter (55% among patients with CRFL2 rearrangement) are more prevalent in BCR-ABL1-like ALL than in other B-ALL sub-types2. The gene discussed is JAK2; the disease is acute lymphoblastic leukemia.