Discovery of the novel HLA‐DRB1*03:77 allele in a Taiwanese unrelated hematopoietic stem cell donor by a sequence‐based typing method and identification of the probable HLA haplotype in association with DRB1*03:77

Summary Here, we report a novel human leucocyte antigen (HLA)‐DRB1 allele, DRB1*03:77, discovered in a Taiwanese unrelated volunteer hematopoietic stem cell donor by a sequence‐based typing (SBT) method. The DNA sequence of DRB1*03:77 is identical to the DNA sequence of DRB1*03:01:01 in exon 2 except one nucleotide at position 223 (G→C). The nucleotide substitution caused an amino acid replacement at residue 46 (E→Q). The formation of DRB1*03:77 was thought as the result of a nucleotide point mutation. The probable HLA‐A, HLA‐B and HLA‐DRB1 haplotype in association with DRB1*03:77 may be deduced as A*33‐B*58‐DRB1*03:77. The donor was a Minna Taiwanese whose ancestors came from mainland China.