In this study, we analyzed the inducibility of the most frequent AML PFGs, namely: KMT2A-MLLT3, RUNX1-RUNX1T1, and PML-RARα in UCB HSPC populations from four newborns, whose UCB MNCs have previously been tested as PFG negative by RT-qPCR (P103, P138, P555, and P558). The gene discussed is MLLT3; the disease is acute myeloid leukemia.