FCGR1A and acute megakaryoblastic leukemia: Immunophenotypically, the CD34+/CD117+ cells in the AMKL patients clearly showed megakaryocytic differentiation, with frequent expression of CD36 (76% of cases) and/or CD42a.CD61 (46% of cases) but lacking markers indicative of other lineages (such as CD19, CD15 and CD64).