DNA测序鉴定新等位基因HLA-DRB1*1609

Identification of a novel HLA allele DRB1*1609 by sequencing-based typing

目的鉴定HLA新等位基因DRB1*1609。方法应用分子克隆和DNA测序的技术测定HLA新等位基因的核苷酸序列,进行HLA等位基因序列比对分析和新等位基因的血清学分型及家系分析。结果新等位基因DRB1第二外显子(exon2,Ex2)序列与所有已知的HLA等位基因序列均不相同,与同源性最高的HLA-DRB1*160101相比,第127位碱基由A→T,引起相应编码第47位氨基酸由酪氨酸Tyr(Y)→苯丙氨酸Phe(F)。血清学分型表明抗原特异性为DR16。家系分析提示该志愿者DRB1*1609等位基因遗传自母亲。结论DNA测序表明被测标本含有HLA-DRB1新等位基因,被WHO HLA因子命名委员会正式命名为HLA-DRB1*1609。

Objective To identify a novel HLA allele DRB1 ＊ 1609 from a donor of Chinese Marrow Donor Program （CMDP）. Methods Molecular cloning and DNA sequencing were used to identify the sequence of a potential novel HL4-DRB1 allele. HLA serological typing as well as the family genetic investigation was performed for the new HLA allele. Results The DRB1 exon 2 nucleotide sequence of the novel allele was different from all other known alleles, h has one nucleotide substitution at position 127 from A to T （codon 47 ACC→TCC） resulting in an amino acid change from Tyr（Y）→Phe（F） compared to the most homologous allele DRB1 ＊ 160101. However, serologic specificity remained DR16 based on serological HLA typing. Family genetic analysis indicated that the novel allele DRB1 ＊ 1609 of the donor was inherited from his mother. Conclusion A novel HLA allele was confirmed by the sequenoing based typing （SBT） and it was officially designated as HLA-DRB1 ＊ 1609 by WHO Nomenclature Committee for Factors of the HLA System in February, 2005.