KIR3DL1 and acute myeloid leukemia: Since the seminal studies by Cooley et al. in the context of HLA-matched and -mismatched T-cell-replete unrelated donor transplantation—which suggested that Cen-B genes confer protection against relapse and improve survival, at least in AML [1]—multiple investigations have sought to elucidate the differential clinical impact of KIR domain localization (Cen vs. Tel) on transplantation outcomes [1].