title: Identification of a novel DRB1 allele through intergenic recombination between HLA-DRB1 and HLA-DRB3∗02 in a Chinese family.
abstract: In this study, a novel DRB1 allele was revealed by routine HLA-SBT typing noted for its extensive mismatches to any known DRB1 alleles within the exon 2. Sequences containing the exons 2, 3 of HLA-DRB1, their surrounding introns, and the full-length cDNA of DRB1 were analyzed to determine a possible recombination event. Interestingly, the sequences of entire exon 2 were characterized as DRB3(∗)02:02:01:01/02; while exon 3 were characterized as DRB1(∗)14 like alleles. Further analysis of the sequences using Simplot software suggested that an intergenic recombinant event (i.e. exchange of sequence between non-allelic genes) may have occurred between DRB3(∗)02 allele and DRB1(∗)14 like allele, and the recombination sites are located at intron 1 and the boundary of exon 2 and intron 2 of DRB1. There are 5 CGGGG sequences flanking each side of exon 2 could serve as potential recombination site. Moreover, the full-length cDNA of the novel allele has been identified. The exon 1 and exon 3 to exon 6 share the same sequence as DRB1(∗)14 like alleles. At the mRNA level, the new allele has no significant difference when compared with the other DRB1 allele. This novel recombinant allele is also found to be paternally inherited. In conclusion, this is the first report of a DRB1 and DRB3 intergenic recombination event involving whole exon 2, which generate a new DRB1(∗)14:141.
authors.affiliation: Department of Microbiology, Peking University Health Science Center, Beijing 100191, China; Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control, Beijing 100050, China.
authors.forename: Weijin
authors.initials: W
authors.lastname: Huang
authors.forename: Xiangjun
authors.initials: X
authors.lastname: Liu
authors.forename: Erwei
authors.initials: E
authors.lastname: Li
authors.forename: Chenyan
authors.initials: C
authors.lastname: Zhao
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Zhenglun
authors.initials: Z
authors.lastname: Liang
authors.forename: Youchun
authors.initials: Y
authors.lastname: Wang
authors.forename: Fengmin
authors.initials: F
authors.lastname: Lu
mesh_terms: D000483:Alleles; D044466:Asian People / Q000235:genetics*; D001483:Base Sequence; D002681:China; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D015870:Gene Expression; D059811:HLA-DRB1 Chains / Q000737:chemistry / Q000235:genetics*; D059826:HLA-DRB3 Chains / Q000737:chemistry / Q000235:genetics*; D006239:Haplotypes; D006650:Histocompatibility Testing; D006801:Humans; D007111:Immunity, Cellular / Q000235:genetics; D008969:Molecular Sequence Data; D010375:Pedigree; D011995:Recombination, Genetic; D016415:Sequence Alignment
chemical_list: D018076:DNA, Complementary; D059811:HLA-DRB1 Chains; D059826:HLA-DRB3 Chains