O等位基因表达弱A抗原伴c.859G>T新突变1例的分子学研究  

Molecular study of a case of O allele expressing weak A antigen with a new mutation of c.859G>T

作　　者：陈萍 王渊元 蔡晓红[3] 张水木 沈雨青[5] 雷航[3] CHEN Ping;WANG Yuanyuan;CAI Xiaohong;ZHANG Shuimu;SHEN Yuqing;LEI Hang(Department of Clinical Laboratory,Xiamen Hospital of Beijing University of Chinese Medicine,Xiamen,361009,China;Department of Blood Transfusion,Zhongshan Hospital School of Medicine Xiamen University;Department of Blood Transfusion,Ruijin Hospital,Shanghai Jiao Tong University School of Medicine;Department of Blood Transfusion,Xiamen Hospital of Beijing University of Chinese Medicine;Department of Blood Transfusion,Women and Children's Hospital School of Medicine Xiamen University)

机构地区：[1]北京中医药大学厦门医院检验科,福建厦门361009 [2]厦门大学附属中山医院输血科 [3]上海交通大学医学院附属瑞金医院临床输血科 [4]北京中医药大学厦门医院输血科 [5]厦门大学附属妇女儿童医院输血科

出　　处：《临床血液学杂志》2023年第10期755-758,共4页Journal of Clinical Hematology

基　　金：国家自然基金青年项目(No:82000183);中国输血协会威高科研基金(No:CSBT-WG-2019-01);厦门市科技局医疗卫生项目(No:3502Z20194047)。

摘　　要：为研究1例ABO正反定型不符的先证者弱A抗原可能的分子机制,应用血型血清学方法对其进行ABO血型鉴定,采用聚合酶链式反应(PCR)扩增ABO基因的CDS区域并直接测序分析标本的基因型;通过克隆和测序对先证者的单倍型进行确认;通过短串联重复试验(STR)和液滴数字聚合酶链式反应(ddPCR)研究先证者的嵌合状态。血型血清学结果显示先证者血型正反不符,室温环境中,先证者血清与B细胞呈强凝集(4+),而与A细胞则没有凝集反应,吸收放散试验表明先证者红细胞上存在痕量的A抗原(±)。直接测序和克隆后测序结果表明先证者含有基于ABO*O.01.02背景的新突变c.859G>T,其ABO基因型为ABO*O.01.02-var/O.01.01。ddPCR和STR的结果表明先证者不含有A等位基因,弱A表达不是由嵌合体引起的。因此我们发现了一种不寻常的弱A表型,该表型先证者仅携带2个含有c.261delG的O等位基因,且该罕见现象不是由嵌合体引起的,261缺失型O等位基因亦可表达出弱A抗原。To study the possible molecular mechanism of the weak A antigen in a proband with inconsistent ABO positive and negative stereotypes, the blood group phenotype of the proband was identified by blood group serology, the CDS region of ABO gene was amplified by polymerase chain reaction(PCR) and the genotypes of the samples were analyzed by direct sequencing. The haplotype of the proband was confirmed by cloning and sequencing. Short tandem repeat tests(STR) and droplet digital polymerase chain reaction(ddPCR) were used to study the chimerism status of the proband. The blood group serological results showed that the blood group of the proband was inconsistent. At room temperature, the serum of the proband showed strong agglutination(4+) with B cells, but no agglutination reaction with A cells. Absorption and release test showed trace amount of A antigen(±) on the red blood cells of the proband. The results of direct sequencing and post-cloning sequencing showed that the proband contained a new mutation c. 859G>T based on the ABO*O. 01.02 background, and its ABO genotype was ABO*O. 01.02-var/O. 01.01. The ddPCR and STR results showed that the proband did not contain the A allele and weak A expression was not caused by chimeras. Thus an unusual weak A phenotype was found in which the proband carried only two O alleles containing c. 261delG, and this rare phenomenon was not caused by chimera. The O allele 261 deletion also expressed weak A antigen.

关 键 词：ABO血型 正反定型不符 基因分型 嵌合体 

分 类 号：R457.1[医药卫生—治疗学]