HLA-DRB1 and acute graft versus host disease: According to the multiple model, HLA-B*07 and HLA-DRB1*07 were significantly associated with the incidence of grades II-IV acute GVHD in which by holding the effect of other variables constant, the presence of HLA-B*07 was associated with 3.84-fold increased odds of incidence (AOR: 3.84; 90% CI: 1.37-10.72; P = 0.031).