Molecular mechanism of Ael blood group caused by ABO
B.01-O.01.02 gene recombination
10.13303/j.cjbt.issn.1004-549x.2026.04.017
- VernacularTitle:ABO
B.01-O.01.02基因重组导致Ael血型的分子机制研究
- Author:
Xiaoyun BU
1
;
Jing HAI
1
;
Jiancheng LIU
1
Author Information
1. Ningxia Blood Center, Yinchuan 750000, China
- Publication Type:Journal Article
- Keywords:
ABO blood group system;
gene recombination;
Ael phenotype;
third-generation sequencing;
bioinformatics analysis
- From:
Chinese Journal of Blood Transfusion
2026;39(4):534-539
- CountryChina
- Language:Chinese
-
Abstract:
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-specific primer polymerase chain reaction (PCR-SSP). The genotype was identified by Oxford Nanopore third-generation sequencing (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 profile. TGS obtained two full-length ABO haplotype sequences: the first was ABO
O.01.02, and the second was a recombinant haplotype of ABO
B.01-O.01.02, with the recombination breakpoint mapped between c. 357-39 and c. 526G>C. Mutations 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 structure modeling revealed alterations in local conformation and hydrogen bond network, and functional prediction indicated decreased protein stability. Conclusion: A recombination between ABO alleles B.01 and O.01.02 was identified in the region 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, ultimately manifesting as the Ael blood group phenotype.
