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. Here, FANCB is linked to acute myeloid leukemia.