Six splice site variations, three of them novel, in the ABO gene occurring in nine individuals with ABO subtypes

• Published in: Journal of translational medicine Vol. 19; no. 1; p. 470
• Main Authors: Hong, Xiaozhen, Ying, Yanling, Zhang, Jingjing, Chen, Shu, Xu, Xianguo, He, Ji, Zhu, Faming
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 22.11.2021; BioMed Central; BMC
• Subjects: ABO Blood-Group System - genetics; ABO subtype; ABO system; Alleles; Antigens; Blood & organ donations; Blood groups; Blood transfusion; Blood transfusions; Cloning; Erythrocytes; Genetic aspects; Genetic variation; Glycosyltransferase; Haplotypes; Health aspects; Humans; Identification and classification; Laboratories; Mutation - genetics; Phenotype; Phenotypes; Polymerase chain reaction; Polymerase chain reaction sequence-based typing; Polymorphism; Sequence Analysis, DNA; Serology; Software; Splice site; Variation; China; United States > US; Zhejiang China; Polymerase chain reaction sequence-based typing; ABO subtype; Variation; Splice site
• ISSN: 1479-5876; 1479-5876
• DOI: 10.1186/s12967-021-03141-5

Nucleotide mutations in the ABO gene may reduce the activity of glycosyltransferase, resulting in lower levels of A or B antigen expression in red blood cells. Six known splice sites have been identified according to the database of red cell immunogenetics and the blood group terminology of the International Society of Blood Transfusion. Here, we describe six distinct splice site variants in individuals with ABO subtypes. The ABO phenotype was examined using a conventional serological method. A polymerase chain reaction sequence-based typing method was used to examine the whole coding sequence of the ABO gene. The ABO gene haplotypes were studied using allele-specific primer amplification or cloning technology. In silico analytic tools were used to assess the functional effect of splice site variations. Six distinct variants in the ABO gene splice sites were identified in nine individuals with ABO subtypes, including c.28 + 1_2delGT, c.28 + 5G > A, c.28 + 5G > C, c.155 + 5G > A, c.204-1G > A and c.374 + 5G > A. c.28 + 1_2delGT was detected in an A individual, while c.28 + 5G > A, c.28 + 5G > C, and c.204-1G > A were detected in B individuals. c.155 + 5G > A was detected in one B and two AB individuals, whereas c.374 + 5G > A was identified in two A individuals. Three novel splice site variants (c.28 + 1_2delGT, c.28 + 5G > A and c.28 + 5G > C) in the ABO gene were discovered, all of which resulted in low antigen expression. In silico analysis revealed that all variants had the potential to alter splice transcripts. Three novel splice site variations in the ABO gene were identified in Chinese individuals, resulting in decreased A or B antigen expression and the formation of ABO subtypes.