Those who no rearrangement is present and/or CRLF2 protein expression is absent undergo Archer multiplex fusion assay and FISH for ABL1, ABL2, PDGFRB, JAK2, and EPOR to assess for multitude of fusions that have been described in non-CRLF2 Ph-like ALL [62–64]. The gene discussed is CRLF2; the disease is acute lymphoblastic leukemia.