一个B抗原减弱表型核心家系的分子遗传学分析

Molecular genetic analysis of a family trio with weak B phenotype

目的分析1例B抗原减弱表型核心家系的血清学和分子生物学特征。方法应用血型血清学方法进行血型鉴定;采用序列特异性引物聚合酶链反应进行ABO基因分型,之后对ABO基因第6、7外显子核苷酸序列进行测序分析。结果血清学鉴定先证者和其父亲均为B亚型(Bw),母亲是O型;ABO基因分型显示先证者和其父亲均为Bw12/O型,先证者母亲为O01/O01型;ABO基因第6、7外显子测序分析也发现先证者和其父亲的基因型为Bw12/O01型。与B101/O01基因序列比对,Bw12仅在278位发生了C>T的突变。结论ABO基因第278位碱基C>T突变为Bw亚型的分子基础,该突变可以稳定遗传并显性表达。

Objective To explore serological and molecular characteristics of a family trio with weak B phenotype.Methods ABO blood type of the family was determined with a serological method.Genotypes of the ABO gene were determined with PCR-sequence specific primer (PCR-SSP).Sequences of exons 6and 7of the ABO gene were analyzed by PCR sequence-based testing.Results Serologically,the proband and her father were determined as B subtype (Bw),while her mother was of O group.The genotypes of the proband and her father were Bw12/O,while her mother was O01/O01.Sequencing of exons 6and 7 of the ABO gene confirmed that the proband and her father were Bw12/O01.Compared with B101/O01,the Bw12 subtype carried a missense mutation (278C>T)in exon 6 of the ABO gene.Conclusion The 278C>T mutation probably underlies the Bw phenotype and can be transmitted stably.