ABO*B.01-O.01.02基因重组导致Ael血型的分子机制研究OA

Objective To analyze the serological and molecular biological characteristics of one case with Ael subtype.Methods ABO serological typing was performed using the tube method.ABO genotyping was conducted by sequence-spe-cific primer polymerase chain reaction(PCR-SSP).The genotype was identified by Oxford Nanopore third-generation se-quencing(TGS).Pymol,Polyphen-2,PROVEAN,and DUET were used to predict the effects of mutations on protein structure and function.Results Serological testing identified an Ael subtype.PCR-SSP genotyping showed an A/O2 pro-file.TGS obtained two full-length ABO haplotype sequences:the first was ABO*O.01.02,and the second was a recombi-nant haplotype of ABO*B.01-O.01.02,with the recombination breakpoint mapped between c.357-39 and c.526G＞C.Mu-tations on this recombinant allele included c.297A＞G,c.646T＞A,c.681G＞A,c.771C＞T,and c.829G＞A,among which c.646T＞A(p.Phe216Ile)and c.829G＞A(p.Val277Met)were two functional amino acid substitution sites.Protein struc-ture modeling revealed alterations in local conformation and hydrogen bond network,and functional prediction indicated de-creased protein stability.Conclusion A recombination between ABO alleles B.01 and O.01.02 was identified in the re-gion spanning intron 6 to exon 7,resulting in a B.01-O.01.02 recombinant gene.This recombinant leads to key amino acid substitutions in the B glycosyltransferase,causing local structural changes and decreased stability of the enzyme protein,ul-timately manifesting as the Ael blood group phenotype.