Overall survival following HLA-identical sibling HSCT for myeloid disease is significantly reduced in recipients homozygous for C2 if the donor is positive for KIR2DS2. Kaplan-Meier plot demonstrating the effect of overall survival following HLA-identical sibling HSCT for myeloid disease. (i) KIR2DS2 absent (n = 12), and (ii) KIR2DS2 present (n = 10).