For instance, loss of HOXA5 in breast cancer [6], over-expression of HOXA10 in acute myeloid leukemia (AML) [7], gene mutations of HOXD4 in renal and colon cancer [8] and overexpression of HOXC4 in human bladder cancer [9] have been reported. The gene discussed is HOXD4; the disease is acute myeloid leukemia.