Thus, this may explain the concordance of the main APL phenotypic characteristics (MPO+CD117+HLA-DR−CD34−CD13+CD33+) with the inconsistency of their positive rate and/or expression MFI, and even greater difference in the mature markers (CD64, CD11c, CD11b, CD10, SSC signal and etc.)in the literature [10, 17–20]. The gene discussed is CD33; the disease is acute promyelocytic leukemia.