一例HLA-A新等位基因HLA-A＊9206的测序分析

Sequence analysis of a novel human leukocyte antigen allele HLA-A ＊ 9206

目的研究人类白细胞抗原（human leukocyte antigen，HLA）新的等位基因HLA-A＊9206的序列及其分子机制。方法样本DNA抽提采用PEL-FREEZ抽提试剂盒，应用PCR方法扩增先证者HLA-A等位基因的第1。8外显子，进行第2-4外显子双向测序分析，发现突变位点。应用序列特异性引物PCR方法获得等位基因的单链，测序后确定双链测序所发现的突变。结果先证者样本单链测序得到两个等位基因，其中一个等位基因为A＊1101，另一个经Blast验证其为新的等位基因，新的等位基因序列已递交GenBank（EF062306）。与最接近的A＊0206等位基因序列相比，新的等位基因在第3外显子上有1个核苷酸不同，第530位pT，导致第153位丙氨酸→缬氨酸。结论该等位基因为新的HLA-A等位基因，被世界卫生组织HLA因子命名委员会正式命名为HLA-＊9206。

Objective To investigate the molecular genetic basis for a human leukocyte antigen（HLA） novel allele HLA-A ＊ 9206 in the Chinese population. Methods DNA was extracted from whole blood by PEL-FREEZ DNA extraction kit. The amplification of HLA-A exons 1-8 of the proband was preformed and the PCR products were sequenced using ABI sequencing kit. Both strands of exons 2, 3 and 4 of the amplified product were sequenced. The polymerase chain reaction-sequence specific primer（PCR-SSP） was performed to split the two alleles apart and confirm the mutations detected by sequencing, Results The sequencing results showed that the HLA-A alleles of the proband were A ＊ 1101 and a novel allele. The sequence of the novel allele has been submitted to GenBank（EF062306）. After Blast analysis, the novel allele shows one nucleotide different from the HLA-A ＊ 0206 in exon 3 at nucleotide position 530 （ C to T）. This results in an amino acid change from Ala to Val at codon 153. Conclusion This allele is a novel allele and has been officially named A ＊ 9206 by the WHO Nomenclature Committee.