The Novel Variant c.122delG on the ABO*B3.0x Allele Associated with B3 Phenotype

Yu Zhang; Yating Ling; Meng Li; Qiang Fu; Chengtao He

doi:10.1159/000547552

The Novel Variant c.122delG on the ABOB3.0x* Allele Associated with B₃ Phenotype

Transfus Med Hemother. 2025 Jul 24;52(6):390-392. doi: 10.1159/000547552. eCollection 2025 Dec.

Authors

Yu Zhang^{1

2}, Yating Ling^{1

2}, Meng Li³, Qiang Fu², Chengtao He^{1

2}

Affiliations

¹ Blood Group Reference Laboratory, Nanjing Red Cross Blood Center, Nanjing, China.
² Key Laboratory of Transfusion Medicine, Nanjing Red Cross Blood Center, Nanjing, China.
³ Blood Transfusion Department, Children's Hospital of Nanjing Medical University, Nanjing, China.

Abstract

Introduction: B₃ is known to be one of the B subtypes that are characterized by serologic mixed-field agglutination. The proportion of Chinese Han individuals with the B₃ subtype (B type) and AB₃ subtype (AB type) is about 1/900 and 1/1,800, respectively. Here, we identified a novel ABO subgroup allele that caused B₃ phenotype.

Methods: The ABO phenotypes of the proband and his father were typed with the traditional test tube method. The ABO genotype was analyzed by SMRT sequencing.

Results: A c.122delG variant was identified in both the proband and his father, who exhibited the B₃ phenotype. This variation results in a premature stop codon, leading to mixed-field agglutination of the serological B antigen.

Conclusion: The novel variation of c.122delG in the exon 3 of ABO*B3.0x allele were identified in Chinese individuals, resulting in mixed-field agglutination of B antigen expression and the formation of ABO subtypes.

Keywords: ABO*B3.0x allele; B3 phenotype; Variant.