Identification of two new HLA-DRB1 alleles: HLA-DRB1*1350 and DRB1*140502

Two probable human leukocyte antigen haplotypes in association with human leukocyte antigen HLA-DRB1*13:50:01 identified in 41 randomized unrelated Taiwanese individuals

Objectives:

Here, we show two probable haplotypes associated with the human leukocyte antigen (HLA) DRB1*13:50:01 allele. The haplotypes were observed from 41 randomized unrelated Taiwanese individuals among a population of 23,064 individuals tested.

Materials and Methods:

The samples in this study were blood samples, preserved in dipotassium ethylenediaminetetraacetic acid and/or ACD anticoagulants. The population is of donors from Tzu Chi Bone Marrow Donor Registry. Allele typing was performed using the sequence-based typing method, Sanger's sequencing. To discern the HLA-A and HLA-B alleles, exons 2 and 3 were sequenced. For DRB1 alleles, exon 2 was sequenced. Target exon sequence amplifications were done by a polymerase chain reaction and the resulting amplicons were sequenced by Bigdye Terminator Cycle Sequencing Ready Reaction kit, according to the manufacturer's protocols.

Results:

Two probable haplotypes that are associated with the DRB1*13:50:01 were observed among the 23,064 Taiwanese randomized unrelated individuals. One of the haplotypes is observed in 39 individuals while the other in two individuals.

Conclusion:

The findings in this study may be useful in studies reinforcing the understanding and clinical application of the polymorphism of HLA genes and haplotypes.

Identification of two novel HLA-DRB1 alleles, HLA-DRB1*1214 and HLA-DRB1*1215, in two Taiwanese individuals

Two novel HLA-DRB1 alleles, HLA-DRB1*1214 and HLA-DRB1*1215, were found in Taiwan using sequence-based typing method. DRB1*1214 differs from DRB1*120101 by two nucleotide substitutions on exon 2, causing amino acid changes at codon 37 (L-->F) and codon 38 (L-->V). We suggest that DRB1*1214 is the product of a gene conversion between DRB1*120101 and DRB1*140101 or DRB1*1405 and that HLA-DRB1*1215 differs from DRB1*120201 by one single nucleotide transition at exon 2, thereby causing amino acid change at codon 37 (L-->F).