Twelve SNPs of clinical significance in HLA-mismatched unrelated donor transplantation. Each of the 12 SNPs having an association with grades II-IV or III-IV acute GVHD, chronic GVHD, relapse, transplant-related mortality, disease-free survival, or survival are shown on a map of the MHC on chromosome 6p21.3 (not to scale). SNPs are identified by their rs numbers. Chromosome 6 drawing modified from the National Library of Medicine, the National Center for Biotechnology Information public website.²¹