人类白细胞抗原新等位基因B*55:35的鉴定及家系调查

摘要

目的 鉴定人类白细胞抗原(human leukocyte antigen,HLA)基因B位点的1个新等位基因并调查其遗传情况.方法 应用聚合酶链反应-序列特异性寡核苷酸探针(polymerase chain reactionsequence specific oligonucleotide probe,PCR-SSOP) HLA分型技术发现1个疑似的新HLA等位基因,通过DNA测序鉴定其序列,并与同源性最高的HLA基因进行核苷酸序列比对,对携带者家系进行调查.结果应用PCR-SSOP进行HLA基因分型时,该样本HLA-B位点反应格局异常.DNA序列分析证实其为1个新HLA-B等位基因.与同源性最高的等位基因B*55:02比较,在第2外显子区域中有7个碱基发生改变,导致6个密码子发生了变化,造成2个氨基酸改变,即第69位的氨基酸由谷氨酸(Glu)变为甲硫氨酸(Met)、第70位的氨基酸由谷氨酸(Glu)变为丙氨酸(Ala).结论 发现并鉴定了HLA-B位点的1个新等位基因,GenBank注册号为FJ898284,被世界卫生组织HLA因子命名委员会正式命名为HLA-B* 55:35.%Objective To identify a novel human leukocyte antigen (HLA) B allele and explore its family heritage.Methods A novel HLA allele was suspected upon routine HLA typing using a polymerase chain reaction-sequence specific oligonucleotide probe (PCR-SSOP) assay.The sequence was confirmed with DNA sequencing and compared with its closest matching allele,B * 55∶ 02.The family was also investigated.Results An unusual reaction pattern was detected during routine HLA typing.The sequence was confirmed to be a new HLA-B allele,which differed from the closest matching allele,B * 55∶02,in 7 nt positions in exon 2.Among the 7 mutations from 6 codons,there were two amino acids changes including 69Glu→Met and 70Glu→Ala.Conclusion A novel HLA-B allele has been identified and officially named as B* 55:35 by the WHO Nomenclature Committee for Factors of the HLA System (GenBank accession number FJ898284).