One-year cumulative incidence of relapse and probability of OS in the 80 HLA-C1/x patients grouped according to the KIR-HLA genotype of the donor CB graft. The 31 HLA-C1/x patients receiving at least one CB unit with the HLA-C1-KIR2DL2/L3/S2 (red line) have a significantly lower incidence of relapse (A) and better OS (B) compared with the 15 patients receiving CB grafts that were predicted to be unlicensed (HLA-C1-negative, blue line) and to the 34 patients receiving KIR2DS2-negative grafts (green line). Tick marks on the lines indicate censored patients.