Combinatorial expression of multiple phenotypic markers facilitated the exhaustive exploration and precise identification of 14 BM cell populations in the absence of morphological parameters, among which included cell populations relevant to the diagnosis of AML: HSCs, CD34+ myeloblasts, more mature CD117+ myeloblasts, monoblasts, and immature monocytic cells. The gene discussed is CD34; the disease is acute myeloid leukemia.