While initial studies suggested that AML-LSCs are restricted to the rare quiescent CD34+CD38− cell population, follow-up studies demonstrated that, especially in relapsed AML, LSCs are present within all bone marrow HSPC populations and, in part, highly proliferative (Iwasaki et al., 2015; Ho et al., 2016; Pollyea and Jordan, 2017). The gene discussed is CD34; the disease is acute myeloid leukemia.