摘要
目的探讨1例ABO血型正反定型不符个体的分子机制。方法选取2023年3月8日于深圳市血液中心献血的1例受试者为研究对象。利用血型血清学检测方法鉴定受试者的ABO表型;用体外酶活性试验测定其血清中B糖基转移酶(GTB)的活性;扩增ABO基因第1~7外显子及侧翼序列并进行Sanger测序,采用TA克隆技术分离单倍体并进行测序,确定其基因型。结果ABO血型血清学鉴定显示正定型为O型、反定型为O型(价差≥2);体外酶活性试验未检测到GTB活性。单倍体克隆测序分析发现受试者的ABO等位基因型为c.213-217delC in ABO*B.01/ABO*O.01.02。ABO*B.01等位基因上存在c.213-217delC单碱基缺失,可导致GTB第73位的谷氨酰胺替换为丝氨酸(p.Gln73Ser),并导致终止密码提前出现(73fs+3aaX),此变异既往未见报道。结论ABO*B.01等位基因上的c.213-217delC单碱基缺失引起的移码突变可导致B抗原缺失。
Objective To investigate the molecular mechanism in a case of ABO typing discrepancy.Methods A blood donor was enrolled on March 8,2023 at the Shenzhen Blood Center.The ABO phenotype was identified using serological testing methods.Enzyme activity assay was performed to determine the activity of B-glycosyltransferase(GTB)in serum.ABO gene exons 1–7 and flanking sequences were amplified and subjected to Sanger sequencing.Haplotypes were determined by isolating haploid DNA using TA cloning technology and subsequent sequencing.Results Serological analysis revealed the forward type as O and the reverse type as O(difference in titer≥2).Enzyme activity assay conducted in vitro did not detect any GTB activity.Haplotype cloning and sequencing analysis identified the ABO allelic genotype of the participant as c.213-217delC in ABO*B.01/ABO*O.01.02.A single-base deletion,c.213-217delC,was observed in the ABO*B.01 allele gene,resulting in the substitution of glutamine with serine at position 73 of GTB(p.Gln73Ser)and premature termination codon appearance(73fs+3aaX).This variation has not been reported previously.Conclusion The frame-shift mutation caused by the single-base deletion c.213-217delC on the ABO*B.01 allele gene results in the loss of B antigen.
作者
梁爽
马雅琳
吴凡
刘通
孙丽艳
汤戎
曾劲峰
LIANG Shuang;MA Yalin;WU Fan;LIU Tong;SUN Liyan;TANG Rong;ZENG Jinfeng(Shenzhen Blood Center,Shenzhen 518035;Heze Medical College,Heze 274000;Yunnan Kunming Blood Center,Kunming 650000)
出处
《临床输血与检验》
2025年第4期526-529,共4页
Journal of Clinical Transfusion and Laboratory Medicine
基金
广东省基础与应用基础研究基金深圳市联合基金项目(No.2022A1515110195)
深圳市自然科学基金项目(No.JCYJ20230807154000002)
深圳市医疗卫生三名工程项目(No.SZSM202311032)
深圳市输血医学重点学科项目(No.SZXK070)资助。
关键词
ABO血型
基因测序
单碱基缺失
ABO blood group
Gene sequencing
Single-base deletion
