Identification of 400 novel alleles at the HLA-A, -B, -C, -DRB1, -DQB1 loci from China Marrow Donor Program

Four hundred novel human leukocyte antigen (HLA) alleles were identified in Chinese individuals: 100 HLA-A alleles, 100 HLA-B alleles, 101 HLA-C alleles, 28 HLA-DRB1 alleles and 71 HLA-DQB1 alleles. Comparing novel alleles with their most homologous allele, we found 72.73% non-synonymous nucleotide substitutions, 21.13% silent mutations, 3.90% nonsense mutations and 3.25% frameshift mutation. 352 (88%) of the 400 novel alleles are single nucleotide substitution variants when compared with their most homologous alleles and other novel alleles differ from their most similar allele by more than 1 nucleotide substitutions, such as 2, 3, 5, 6, 8 and so on. Some of the novel alleles are characterized by long deletions or insertions, for example there is 23 bp deletion in the B*58:31N allele when compared to its most homologous allele B*58:01:01:01.