The key genes which served as transcription factors in early hematopoiesis, such as MEF2C, LYL1, LMO2, HHEX, RUNX2, HOXA10, HOXA9, RUNX1T1, and ZBTB16, were up-regulated in immature T-ALL. The gene discussed is HOXA9; the disease is acute lymphoblastic leukemia.