Detection of the rare HLA-B*40: 97 allele in an unrelated Taiwanese bone marrow donor

We detected a rare HLA-B locus allele, B*40:97, in a Taiwanese unrelated donor in our routine HLA SBT (sequence-based typing) exercise for a possible hematopoietic stem cell donation. In exons 2, 3 and 4, the sequence of B*40:97 is identical to the sequence of B*40:02:01 except one nucleotide at nucleotide position 760 (C->T) in exon 4. The nucleotide variation caused one amino acid alteration at residue 230 (L->F). B*40:97 was probably derived from a nucleotide substitution event where C was replaced by T at nucleotide 760 involving B*40:02:01. The HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 haplotype in association with B*40:97 may be deduced as A*26:01-B*40:97-C*03:03-DRB1*11:01-DQB1*03:03. Our recognition of B*40:97 in Taiwanese helps to fill the void of ethnic information for the allele B*40:97 reported to the IMGT/HLA Database.