新等位基因HLA-B＊9526的确认和序列分析

Identification of a novel HLA allele HLA-B ＊ 9526

目的鉴定中国人群中人类白细胞抗原（humanleukocyteantigen，HLA）新等位基因HLAB＊9526，并进行核苷酸序列分析。方法使用序列特异性寡核苷酸PCR技术进行HLA基因分型，发现1个反应格局异常的等位基因，应用分子克隆和DNA双向测序技术测定新等位基因的核苷酸序列，并与已知等位基因进行序列比对分析。结果检出反应格局异常的DNA样本，经过克隆测序得到两个等位基因，分型结果一个为B＊5403，另一个的核苷酸序列与已知的HI。A等位基因均不同，该基因序列与同源性最高的HLAB＊1507基因序列相比在第3外显子区域中425位碱基发生A→G突变，导致142位编码氨基酸由酪氨酸变成半胱氨酸。结论一个新的HLA—B等位基因被确认，并被世界卫生组织HLA因子命名委员会正式命名为HLAB＊9526。

Objective A novel human leukocyte antigen-B （HLA-B） allele, B ＊ 9526, was identified and analyzed by sequencing-based method in a Chinese donor. Methods HLA typing was performed by PCR sequence specific oligonucleotide （SSO）. Molecular cloning and DNA sequencing were used to identify the sequence of the potential novel allele and the difference between this new allele and other known alleles were analyzed. Results HLA genotyping of one sample gave different results. The sequencing result showed HLA B alleles of the proband as B ＊ 5403 and a novel allele. The nucleotide sequence of the novel allele was different from all known B alleles and harbored one nucleotide change from the closest matching allele B 1507 at nucleotide 425 （A→G） in exon 3, resulting in an amino acid change from Y （TAC） to C （TGC） at codon 142. Conclusion A novel HLA allele was identified and officially designated as HLA B ＊ 9526 by WHO Nomenclature Committee for Factors of the HLA System.