α-1,3-N-乙酰半乳糖胺基转移酶基因742C>T突变导致A2亚型  

C742T Mutation of α1,3 N-acetyl-D-galactosaminyltransferase Gene is Responsible for A2 Subgroup

作　　者：洪小珍[1] 应燕玲[1] 许先国[1] 马开荣[1] 蓝小飞[1] 刘瑛[1] 朱发明[1] 吕杭军[1] 严力行[1] 

机构地区：[1]浙江省血液中心卫生部血液安全研究重点实验室,浙江杭州310006

出　　处：《中国实验血液学杂志》2011年第3期702-705,共4页Journal of Experimental Hematology

基　　金：国家自然科学基金(编号30772065;30871112);浙江省医药卫生科学研究基金(编号2009A048)

摘　　要：本研究探讨2例ABO亚型A2B的分子机制。利用单克隆抗体检测先证者红细胞ABO血型抗原,用标准A、B、O细胞检测先证者血清中的ABO抗体,采用聚合酶链反应(polymerase chain reaction,PCR)技术扩增先证者ABO基因的第5至7外显子序列,其PCR产物经酶切后直接测序分析。同时,PCR产物经TOPO TA克隆到质粒载体中获得单链,对所得克隆进行ABO基因第6、7外显子双向测序分析。结果表明,先证者红细胞有A、B抗原,同时其血清中存在抗A1抗体。直接测序分析发现,第261位无缺失,第297位A/G、467C/T、526C/G、657C/T、703G/A、742C/T、796C/A、803G/C、930G/A杂合。克隆测序得到B101和1个新的A等位基因。与A102相比,新A等位基因仅在第742位C→T突变,导致第248位精氨酸变成色氨酸,新等位基因已被正式命名为A213。结论 :α-1,3-N-乙酰半乳糖胺基转移酶基因第742位C→T突变导致产生A2表型,表型个体血清中可含有抗A1抗体。The objective of this study was to analyze the molecular genetic basis for 2 individuals with A2B phenotype of ABO subtype. The ABO group antigens on red blood cells were identified by monoclonal antibodies and the ABO antibodies in serum were detected by the standard A, B, O cells. The exon 5 to exon 7 coding region of ABO gene was amplified by polyrnerase chain reaction （PCR） and the PCR product was sequenced directly after the enzymes digested. The amplified product was also cloned by TOPO TA cloning sequencing kit to split the 2 alleles apart and chosen colonies were sequencing bidirectionally for exon 6 to 7 of ABO gene. The results showed that both A and B antigen were identified on red blood cells of the individuals and there was anti-A1 antibody in their serum. There was no 261G deletion and showed 297A/G, 467C/T, 526C/G, 657C/T, 703G/A, 742C/T, 796C/A, 803G/C, 930G/A heterozygotes by direct DNA sequencing. After cloning and sequencing, it was obtained the B101 and one novel A allele. The novel allele has one nucleotide change at 742 position C to T compared with A102 ,which results in an amino acid Arg to Cys at 248 position and was nominated as A213. It is concluded that C742T mutation of the α1, 3 N-acetyl- D-galactosaminyl-transferase gene can lead to A2 phenotype and with anti-A1 antibody in serum.

关 键 词：A2B表型 ABO基因 抗A1抗体 

分 类 号：R457.11[医药卫生—治疗学] R457.1[医药卫生—临床医学]