一个新的A等位基因突变所致A亚型的血清学特点及家系调查

Serological Characteristics of Subtype A Caused by New A Allele Mutation and a Family Survey

目的:1名诊断为支气管扩张症的男性患者的血型正反定型不一致,正向和反向血型分别为O型和A型。本研究对其进行了包括基因分型和测序在内的多项实验及家系调查,以确定其亚型,并探讨该亚型的血清学特点。方法:用标准的血清学技术对先证者及其部分家系成员进行正反定型、反定型增强试验、H抗原鉴定、吸收放散试验、唾液血型物质试验,并利用PCR-SSP法进行ABO基因分型及6、7外显子测序。结果:先证者血型正定型为O型,但吸收放散试验可检出A抗原,反定型增强试验可检出抗-A1,唾液中有H物质但无A物质,血清学特征符合Ael亚型。基因测序分析显示,在A102的基础上发生了从未报道过的c.625T>G碱基替换,家系调查显示c.625T>G的碱基替换出现在了该家系的三代人中。结论:本研究确定了一个由c.625T>G突变引起的具有Ael血清学特征的新等位基因型,c.625T>G碱基替换导致A抗原减弱,这种突变可以稳定地遗传给后代。

Objective:In this study,the results of forward and reverse blood typing of a male patient diagnosed as bronchiectasis were inconsistent,which were type O and type A respectively.Multiple experiments including genotyping and sequencing and family investigation were carried out to determine the subtype of ABO blood group and explore the serological characteristics of this subtype.Methods:Standard serological techniques were used to conduct forward and reverse typing,reverse blood typing enhancement test,H antigen identification,absorption-elution test,salivary blood group substances test,and PCR-SSP method for ABO genotyping and exon 6 and 7 sequencing.Results:The proband's blood group was type O by forward typing,but antigen A could be detected by absorption-elution test,anti-A1 could be detected by reverse blood typing enhancement test,it was found that there was substance H but no substance A in saliva,and the serological characteristics were consistent with Ael subtype.Gene sequencing analysis showed that there was a c.625T>G base substitution on the basis of A102,which had never been reported before.Family survey showed that c.625T>G base substitution appeared in three generations of the family.Conclusion:In this study,a new subtype A with Ael serological characteristics caused by c.625T>G mutation was identified.c.625T>G base substitution results in the weakening of A antigen,and this mutation can be stably passed down to future generations.