Kuo‑Liang Yanga,b*, Zheng‑Zhong Zhengc
aLaboratory of Immunogenetics, Tzu Chi Cord Blood Bank and Buddhist Tzu Chi Marrow Donor Registry, Buddhist Tzu Chi Stem Cells Centre, Hualien Tzu Chi Hospital, Hualien, Taiwan, bDepartment of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien, Taiwan, cDepartment of Research, China Shanghai Tissuebank Diagnostics, Shanghai, China
Open Access funded by Buddhist Compassion Relief Tzu Chi Foundation
Abstract
Objective: Human leukocyte antigen (HLA)‑DRB1*15:140 is a low‑frequency allele in the HLA‑DRB1 locus. The aim of this study is to confirm the ethnicity of DRB1*15:140 and to deduce a probable HLA‑DRB1*15:140‑associated HLA haplotype in Taiwanese individuals. Materials and Methods: A total of 1815 healthy unrelated Taiwanese individuals and 14,562 unrelated mainland Chinese individuals were tested for HLA using a sequence‑based typing method. Polymerase chain reaction was performed to amplify
exons 2 and 3 of the HLA‑A and HLA‑B loci and exons 1 and 2 of the HLA‑DRB1 locus using group‑specific primer sets. The amplicons were sequenced in both directions with the BigDye Terminator Cycle Sequencing Ready Reaction Kit according to the
manufacturer’s protocols. Results: The DNA sequence of HLA‑DRB1*15:140 is identical to DRB1*15:02:01:01 in exons 1 and 2, except at residue 91 of DRB1*15:02:01:01 where a G in DRB1*15:02:01:01 is replaced by an A in DRB1*15:140 (codon 2; GAC‑>AAC). The nucleotide substitution in exon 1 introduces a one amino acid substitution at residue 2 where an aspartic acid (D) in DRB1*15:02:01:01 is replaced by an asparagine (N) in DRB1*15:140. We deduced the probable HLA haplotype associated with DRB1*15:140 in Taiwanese to be HLA‑A*33:03‑B*58:01‑DRB1*15:140. Conclusion: Information on the ethnicity and distribution of DRB1*15:140 and its deduced probable HLA haplotype in association with the low‑incidence allele is of value for HLA‑testing laboratories for reference purposes and can help bone marrow donor registries find compatible donors for patients with this uncommon HLA allele.
Keywords: DRB1*15:140, Haplotype, Human leukocyte antigen, Taiwanese, Transplantation
Open Access funded by Buddhist Compassion Relief Tzu Chi Foundation
