1例HLA新等位基因B*15:201*的发现及确认

Discovery and Idenfication a New Allele of HLA-B*15:201

目的 1个人类白细胞抗原(human leucocyte antigen,HLA)新等位基因的认定和序列分析。方法应用多聚酶链式反应—基于测序的分型技术(polymerase chain reaction-sequence based typing,PCR-SBT)对中国造血干细胞捐献者资料库河北分库捐献者进行HLA高分辨率分型,发现1个HLA-B位点的异常结果,应用序列特异性测序引物(sequence specific sequencing primer,SSSP)分离测序,确认发生突变的等位基因及发生突变的位置。结果发现1例标本的HLA-B位点分型结果不能认定为任何已知结果,利用SSSP引物进行分离测序后发现1条链的等位基因核苷酸序列与所有已知HLA-B位点等位基因核苷酸序列不一致,与同源性最高的等位基因B*15:01:01:01的差异是在第2外显子662位的A>T,其突变导致密码子CAT>CTT,结果造成B*15:01:01:01氨基酸序列中221位的组氨酸(H)变为亮氨酸(L)。结论该等位基因为HLA-B位点的1个新等位基因,被世界卫生组织(WHO)HLA系统命名委员会命名为HLA-B*15:201。

Objective To sequence and identify a novel HLA allele. Methods PCR-SBT method was used for HLA typing and an anomaly allele that is associated with HLA-B locus was analyzed, and sequence-specific sequencing primer（SSSP）was used for sequencing so as to confirm the site of mutation. Results The results showed an new allele of HLA-B locus. SSSP sequencing indicated that the nucleotide sequence of the novel allele is different from the highest homology allele B＊ 15：01：01： 01 in the second exon at position 662 A〉T, resulting in the amino acid sequence at position 221 of B ＊15：01：01：01, mutated from histidine（H） to leucine（L）. Conclusion This is a novel HLA-B allele and has been named HLA-B＊ 15：201 by WHO HLA Nomenclature Committee.