While the present study showed that HLA-DRB1*15 and DQB1*05 (one of the alleles in linkage disequilibrium with DRB1*15) were higher in patients with acute GVHD (grades II to IV), Battiwalla et al. identified absence of HLA-DR15 as a factor significantly associated with acute GVHD.4 This evidence concerns the gene HLA-DRB1 and acute graft versus host disease.