Over the three time periods, there was a progressive increase in older age at CBT, adverse cytogenetics of AML, absence of MDS/MPN, early phase at CBT, cryopreserved TNC dose, cryopreserved CD34+ cell dose, MAC regimens, use of non-TBI regimens, and GVHD prophylaxis without MTX. This evidence concerns the gene CD34 and acute myeloid leukemia.