Long-standing evidence suggests that early detection of measurable residual disease (MRD) by identifying leukemia-associated immunophenotypes (LAIP) by flow cytometry, and fusion transcripts as well as gene expression (e.g., WT1) by quantitative RT-PCR, are able to predict relapse in patients with acute myeloid leukemia (AML) [4,5,6]. The gene discussed is WT1; the disease is acute myeloid leukemia.