Family Studies of a New Allele of the Bel subtype (c.803G>T, p.Gly268Val).
10.19746/j.cnki.issn.1009-2137.2025.02.029
- Author:
Xiao-Li MA
1
;
Wen-An DONG
1
;
He-Cai YANG
1
;
Ming-Lu GENG
1
;
Li-Ping WANG
1
;
Yang YU
2
Author Information
1. Henan Red Cross Blood Center， Zhengzhou 450000， Henan Province, China.
2. Department of Transfusion Medicine, The First Medical Center of Chinese PLA General Hospital, Beijing 100853, China.
- Publication Type:Journal Article
- Keywords:
B
- MeSH:
Point Mutation;
Alleles;
ABO Blood-Group System/genetics*;
Exons;
Introns;
Genotype;
Humans;
Male;
Female;
Glycosyltransferases/genetics*
- From:
Journal of Experimental Hematology
2025;33(2):504-510
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To analyze the Bel subtype gene mutation and its genetic mechanism in a family line.
METHODS:ABO blood groups were identified by serologic tests. ABO genotyping was performed by polymerase chain reaction with sequence-specific primer (PCR-SSP). Sanger sequencing was performed on exons 1-7 of the ABO gene, the flanking intronic region, and exon 7 of the single strand of the gene confirmed the mutation site location. Missense3D software was used to predict the protein structure alteration caused by this mutation.
RESULTS:Conventional serologic tests failed to detect erythrocyte B antigen in the proband and her three family members, and only trace amounts of B antigen expression could be detected by the absorption-dispersal test. DNA analysis showed that, on the basis of the normal ABO gene, there was a G>T substitution in the position of exon 7, position 803, which resulted in the change of amino acid 268 from Gly to Val. Further single-stranded sequencing analysis showed that the mutation site was located in the B gene.
CONCLUSION:In this family line, the proband, her father, her son, and her daughter all have reduced B type glycosyltransferase activity due to the new point mutation (c.803G>T) in exon 7 of the B gene, and the B antigen can only be detected by the absorption-dispersal method, and the point mutation can be stably inherited by offspring.
