ABO ambiguous blood types in voluntary blood donors from Putian, Fujian Province: a serology and molecular biology study

Abstract

Objective To investigate the serological and molecular biology characteristics of ambiguous blood types among voluntary blood donors in Putian, and to file records for relevant donors for future reference in case of their own transfusion needs or emergency donations to others. Methods A total of 68 593 blood samples from voluntary blood donors in Putian Central Blood Station between January 1, 2019 and August 31, 2023 were collected and tested for blood types using serological methods. ABO gene (including promoters, enhancers and seven exons as well as their flanking sequences and intron 6) and FUT1 gene testing were performed on ambiguous blood types.3D models were constructed using Chimira and PyMOL software to predict the impact of gene mutations on enzyme structure. Results A total of 16 ABO subtypes were identified by serological methods, with the highest detection rate as the para-Bombay phenotype (0.73 per 10 000), followed by the cisAB phenotype (0.44 per 10 000). Gene analysis revealed 12 cases with known mutations (4 cases of FUT1.01N.06/FUT1.01N.06, 1 case of FUT1 01W.08/FUT1.01N.06, 2 cases of A2.08/B.01, 1 case of BA.02/O.01.01, 1 case of A3.07/O.01.01, 3 cases of cisAB.01/B.01), and key mutations were not found in 4 cases (2 cases of A1.02/B.01, 2 cases of A1.02/O.01.02). 3D molecular model analysis revealed that both A3.07 and FUT1.01W.08 allele can lead to a decrease in activity of the corresponding glycosyltransferases, resulting in the emergence of subtypes. Conclusion The most common phenotype causing discrepancies in ABO blood type testing among voluntary blood donors from Putian is the para-Bombay phenotype, with the most common allele being FUT1.01N.06.

Keywords

• subtype
• the safety of blood transfusion
• gene sequencing