B_(el)亚型新等位基因(c.803G>T,p.Gly268Val)的家系研究  

Family Studies of a New Allele of the B_(el)subtype(c.803G>T,p.Gly268Val)

作　　者：马晓莉[1] 董文安 杨贺才[1] 耿明璐[1] 王丽萍 于洋 MA Xiao-Li;DONG Wen-An;YANG He-Cai;GENG Ming-Lu;WANG Li-Ping;YU Yang(Henan Red Cross Blood Center,Zhengzhou 450000,Henan Province,China;Department of Transfusion Medicine,The First Medical Center of Chinese PLA General Hospital,Beijing 100853,China)

机构地区：[1]河南省红十字血液中心,河南郑州450000 [2]中国人民解放军总医院第一医学中心输血医学科,北京100853

出　　处：《中国实验血液学杂志》2025年第2期504-510,共7页Journal of Experimental Hematology

基　　金：河南省医学科技攻关计划项目(LHGJ20200251)。

摘　　要：目的:分析1个家系B_(el)亚型基因突变及其遗传机制。方法:通过血清学试验鉴定ABO血型,采用聚合酶链反应序列特异性引物(PCR-SSP)进行ABO基因分型,对ABO基因1-7外显子、侧翼内含子区域进行Sanger测序,7外显子单链测序确认突变点位置。利用Missense3D软件预测该突变点导致的蛋白质结构改变。结果:常规血清学试验未能检测到先证者及其3个家族成员的红细胞B抗原,只能通过吸收放散试验发现有微量的B抗原表达。DNA分析显示,在正常ABO基因基础上,第7外显子803位置出现G>T替换,导致第268位氨基酸由Gly转变为Val。进一步单链测序分析发现该突变位点位于B基因上。结论:该家系中先证者及其父、其子、其女均因B基因第7外显子发生c.803G>T新的点突变导致B型糖基转移酶活性降低,B抗原只能通过吸收放散的方法才能够被检出,该点突变能够稳定遗传给子代。Objective:To analyze the B_(el)subtype gene mutation and its genetic mechanism in a family line.Methods:ABO blood groups were identified by serologic tests.ABO genotyping was performed by polymerase chain reaction with sequence-specific primer(PCR-SSP).Sanger sequencing was performed on exons 1-7 of the ABO gene,the flanking intronic region,and exon 7 of the single strand of the gene confirmed the mutation site location.Missense3D software was used to predict the protein structure alteration caused by this mutation.Results:Conventional serologic tests failed to detect erythrocyte B antigen in the proband and her three family members,and only trace amounts of B antigen expression could be detected by the absorption-dispersal test.DNA analysis showed that,on the basis of the normal ABO gene,there was a G>T substitution in the position of exon 7,position 803,which resulted in the change of amino acid 268 from Gly to Val.Further single-stranded sequencing analysis showed that the mutation site was located in the B gene.Conclusion:In this family line,the proband,her father,her son,and her daughter all have reduced B-type glycosyltransferase activity due to the new point mutation(c.803G>T)in exon 7 of the B gene,and the B antigen can only be detected by the absorption-dispersal method,and the point mutation can be stably inherited by offspring.

关 键 词：B_(el)亚型 ABO亚型 血清学 新等位基因 测序 

分 类 号：R457[医药卫生—治疗学]