A rare ancestral HLA-DRB1*15:01 similar to DQB1*02:01 haplotype and its reversion in the same Western European family

摘要

The HLA-DR and -DQ loci are close neighbors on chromosome 6 that are highly linked. Many common associations between HLA-DR and DQ-alleles are known, normally transmitted as HLA-DR similar to DQ haplotypes from one generation to another. Reports of very recent genetic rearrangements between HLA-DR and -DQ are rarely found in the literature. In Europeans haplotypes containing DRB1*15:01, DQB1*02:01, and DQA1*05:01 have not been reported before. We report the finding of the rare HLA haplotype A*24: 02 similar to C*07:02 similar to B*07:02 similar to MICA*008:01 similar to DRB5*01:01 similar to DRB1*15:01 similar to DQA1*05:01 similar to DQB1*02:01 similar to DPB1*04:01 in a German stem cell donor with East Frisian ancestry. Our observation suggests a rare ancestral recombination between the DR and DQ loci. In order to investigate this haplotype, we typed 50174 members of the family encompassing four generations for HLA classes I and II by serological and molecular methods. The rare haplotype was identified in 12 heterozygous carriers. Furthermore, we identified and further characterized a putative crossing over event resulting in its reversion to a common haplotype. (C) 2015 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.