Two deduced probable HLA-A*24:287-associated HLA haplotypes (A*24:287-B*40-DRB1*15 and A*24:287-B*58-DRB1*03:01) found in Taiwanese unrelated hematopoietic bone marrow stem cell donors-case analysis

摘要

Objective HLA-A*24:287 is a low incidence allele in the HLA-A locus. The objective of this study is to report the ethnicity of A*24:287 and its deduced probable human leukocyte antigen (HLA)-associated haplotypes in Taiwanese unrelated bone marrow hematopoietic stem cell donors. Materials and methods A sequence-based typing method was employed to confirm the low incidence allele A*24:287. Polymerase chain reaction was performed to amplify exon 2 and exon 3 of the HLA-A and HLA-B loci and exon 2 of the HLA-DRB1 locus using group-specific primer sets. The amplicons were sequenced employing BigDye Terminator Cycle Sequencing Ready Reaction kits in both directions according to the manufacturer's protocols. Results The DNA sequence of A*24:287 is identical to A*24:02:01:01 in exons 2 and 3, except for residue 617 where C is changed to G (codon 182, ACG-AGG). The nucleotide exchange leads to an amino acid alteration to the protein sequence of A*24:02:01:01 at residue 182 where the threonine of A*24:02:01:01 is changed to the arginine of A*24:287. We deduced the probable HLA haplotypes in association with A*24:287 in Taiwanese to be A*24:287-B*40-DRB1*15 and A*24:287-B*58-DRB1*03:01. Conclusion Information on the deduced probable HLA haplotypes in association with the low incidence A*24:287 allele that we report here are of value for HLA testing laboratories for reference purposes. In addition, they can be used by stem cell transplantation donor search coordinators to determine a strategy for finding compatible donors in unrelated bone marrow donor registries when a patient has this uncommon HLA allele.