Effect of HLA-A2 allele disparity on clinical outcome in hematopoietic cell transplantation from unrelated donors.

Population-based differences in clinical outcome after unrelated donor hematopoietic cell transplantation suggest that the significance of human leukocyte antigen (HLA) mismatching may be related to locus-specific and allele-specific differences that distinguish ethnically diverse transplant donors and recipients. We studied the risks associated with HLA-A locus mismatching in two large transplant populations from the International Histocompatibility Working Group in hematopoietic cell transplantation data set to better understand permissible and nonpermissible HLA-A mismatches.