GFI1 and myeloid leukemia: Although more work is needed to examine specifically the role of reduced levels in lymphoid leukaemia or loss of Gfi1 in myeloid leukaemia, we postulate that a certain low degree of Gfi1 expression is beneficial for myeloid and lymphoid leukaemia and that deviation from this level disturbs leukaemia progression and would represent an approach for therapeutic intervention.