M6 is also known as erythroleukaemia or Di Guelielmo Syndrome and is typified by the myeloprofileration of erythrocyte precursors while M7, also known as acute megakaryocytic leukaemia, accounts for only 1% of all adult AML cases and arises from immature platelet precursors, unlike the other FAB subtypes (M0–M5) which occur in immature leukocytes. This evidence concerns the gene FANCB and acute megakaryoblastic leukemia.