OBJECTIVE: To explore the serological and molecular genetic characteristics of a family with subtype B(A)06. METHODS: A neonatal hyperbilirubinemia patient who was treated at Henan Children's Hospital on June 15, 2023 due to "yellowing of the skin and gradual aggravation", and was found to have inconsistent ABO forward and reverse typing through blood type testing, was selected as the research subject. Six milliliters of peripheral blood were collected from the newborn and her family members (grandfather, grandmother, father, mother and aunt) respectively. ABO blood group identification was performed by the blood group serological method. Human genomic DNA was extracted using the nucleic acid extraction or purification reagent BT-01. ABO gene exons 2 to 7 were amplified by PCR. The PCR-specific products that were successfully amplified were sequenced by Sanger method. Taking ABO*A1.01 as the reference sequence, the ABO gene sequences of the newborn and her family members were analyzed to determine the ABO genotype. The procedures followed in this study were approved by the Ethics Committee of Henan Children's Hospital (Ethics No.: 2022-K-L036). RESULTS: The serological results of ABO blood group showed that the newborn, her grandfather, father and aunt were all incompatible with the forward and reverse typing. The blood group phenotype of the newborn was AwB or B(A), the blood group phenotype of the grandfather was A2B or B(A), the blood group phenotype of the father and aunt were A2B, and the blood group phenotype of the grandmother and mother were both O. The screening test results of hemolytic disease of the newborn showed that the free test detected IgG anti-A1 antibody, while the elution test, direct antiglobulin test and antibody screening results were all negative. The Sanger sequencing results showed that the newborn had variations of c.261delG, c.297A>G, c.526C>G, c.657C>T, c.703G>A, c.796C>A and c.930G>A. Her grandfather had variations of c.297A>G, C.526C>G, c.657C>T, c.703G>A, c.796C>A, c.803G>C and c.930G>A. Her grandmother had variations of c.106G>T, c.188G>A, c.189C>T, c.220C>T, c.261delG, c.297A>G, c.646T>A, c.681G>A, c.771C>T and c.829G>A. Her father and aunt had variations of c.106G>T, c.188G>A, c.189C>T, c.220C>T, c.261delG, c.297A>G, c.526C>G, c.646T>A, c.657C>T, c.681G>A, c.703G>A, c.771C>T, c.796C>A, c.829G>A and c.930G>A. Her mother had variations of c.106G>T, c.188G>A, c.189C>T, c.220C>T, c.261delG, c.297A>G, c.646T>A, c.681G>A, c.771C>T, and c.829G>A.The genotype of the newborn was ABO*BA.06/ABO*O.01.01, her grandfather was ABO*BA.06/ABO*B.01, her grandmother was ABO*O.01.02/ABO*O.01.02, her father and aunt were ABO*BA.06/ABO*O.01.02, and her mother was ABO*O.01.01/ABO*O.01.02. The ABO*BA.06 allele of the newborn, grandfather, father and aunt was caused by the c.803C>G variation in exon 7 based on the ABO*B.01 allele. The ABO*BA.06 allele can be stably inherited in this family. CONCLUSION The blood type of neonatal patients with B(A)06 subtype can be accurately determined by gene sequencing technology. If the forward typing is ≤ 3+ agglutination intensity in newborn ABO blood group identification, the reason should be carefully analyzed, and the molecular biology technology and family gene sequencing results should be used to jointly determine if necessary.
Humans ; ABO Blood-Group System/genetics* ; Female ; Pedigree ; Male ; Infant, Newborn ; Asian People/genetics* ; Genotype ; China ; Blood Grouping and Crossmatching ; Hyperbilirubinemia, Neonatal/blood* ; East Asian People

OBJECTIVE: To investigate the association between ABO blood types and gestational diabetes mellitus (GDM) risk. METHODS: A prospective birth cohort study was conducted. ABO blood types were determined using the slide method. GDM diagnosis was based on a 75-g, 2-h oral glucose tolerance test (OGTT) according to the criteria of the International Association of Diabetes and Pregnancy Study Groups. Logistic regression was applied to calculate the odds ratios ( ORs) and 95% confidence intervals ( CIs) between ABO blood types and GDM risk. RESULTS: A total of 30,740 pregnant women with a mean age of 31.81 years were enrolled in this study. The ABO blood types distribution was: type O (30.99%), type A (26.58%), type B (32.20%), and type AB (10.23%). GDM was identified in 14.44% of participants. Using blood type O as a reference, GDM risk was not significantly higher for types A ( OR = 1.05) or B ( OR = 1.04). However, women with type AB had a 19% increased risk of GDM ( OR = 1.19, 95% CI = 1.05-1.34; P < 0.05), even after adjusting for various factors. This increased risk for type AB was consistent across subgroup and sensitivity analyses. CONCLUSION The ABO blood types may influence GDM risk, with type AB associated with a higher risk. Incorporating it-either as a single risk factor or in combination with other known factors-could help identify individuals at risk for GDM before or during early pregnancy.
Humans ; Female ; Pregnancy ; Diabetes, Gestational/etiology* ; ABO Blood-Group System ; Adult ; Prospective Studies ; Risk Factors ; Young Adult

Objective To precisely identify the para-Bombay blood types in cancer patients at our hospital, establish a robust system for the identification of challenging blood types in our laboratory, and provide a foundation for precise transfusion practices. Methods We retrospectively analyzed the blood type results of 91 874 cancer patients from January 1, 2019, to December 31, 2023. Conventional serological methods were used to screen for blood types, and suspected para-Bombay blood types were identified. Further analysis was performed using Pacific Biosciences (PacBio) single-molecule real-time sequencing and Sanger sequencing was used to determine the genotypes of the ABO, FUT1, and FUT2 genes. Results Eight cases of para-Bombay blood type were confirmed through serological and molecular biological methods. The FUT1 genotypes identified were: 5 cases of h1h1 (homozygous mutation 551_552delAG) and 3 cases of h1h2 (compound heterozygous mutations of 551_552delAG and 880_882delTT). The FUT2 genotypes identified were: 2 cases of Se³⁵⁷/Se^{357, 716} and 4 cases of Se³⁵⁷/Se³⁵⁷. Additionally, one sample revealed a novel heterozygous mutation, 818C>T, in exon 7 of the ABO gene, which was confirmed by PacBio sequencing to be located on the O haplotype. Conclusion PacBio sequencing technology demonstrates significant advantages in analyzing the haplotypes of para-Bombay blood type genes. This approach supports the establishment of a robust system for the identification of challenging blood types and provides novel evidence for precise transfusion practices in cancer patients.
Humans ; Neoplasms/genetics* ; Fucosyltransferases/genetics* ; ABO Blood-Group System/genetics* ; Male ; High-Throughput Nucleotide Sequencing/methods* ; Galactoside 2-alpha-L-fucosyltransferase ; Female ; Retrospective Studies ; Genotype ; Middle Aged ; Blood Grouping and Crossmatching/methods* ; Adult ; Mutation ; Aged

OBJECTIVES: To investigate the readmission rate and risk factors for readmission due to hyperbilirubinemia in neonates with ABO hemolytic disease of the newborn (ABO-HDN), and to construct a risk prediction model for readmission. METHODS: Neonates diagnosed with hyperbilirubinemia due to ABO-HDN and hospitalized in the neonatal department between January 2021 and December 2023 were enrolled. Based on readmission status, neonates were divided into a readmission group and a control group. Clinical characteristics related to hyperbilirubinemia and risk factors for readmission were analyzed. Subsequently, a prediction model for readmission was constructed, and its predictive performance was evaluated. RESULTS: A total of 483 neonates with hyperbilirubinemia due to ABO-HDN were included. The readmission rate was 13.0% (63 cases). Multivariate logistic regression analysis revealed that earlier age at phototherapy initiation, longer duration of phototherapy, occurrence of rebound hyperbilirubinemia, and higher levels of serum total bilirubin and indirect bilirubin at discharge were independent risk factors for hyperbilirubinemia readmission in ABO-HDN neonates (OR=2.373, 4.840, 6.475, 5.033, 1.336 respectively; P<0.05). A risk prediction model for ABO-HDN hyperbilirubinemia readmission was constructed based on these 5 risk factors. Model evaluation demonstrated good predictive performance. CONCLUSIONS Age at phototherapy initiation, duration of phototherapy, occurrence of rebound hyperbilirubinemia, and serum total bilirubin and indirect bilirubin levels at discharge are significant influencing factors for readmission due to hyperbilirubinemia in neonates with ABO-HDN. Close monitoring during discharge planning and follow-up management for such neonates is crucial to reduce readmission rates.
Humans ; Infant, Newborn ; ABO Blood-Group System ; Risk Factors ; Patient Readmission ; Male ; Female ; Logistic Models ; Hyperbilirubinemia, Neonatal/therapy* ; Erythroblastosis, Fetal ; Bilirubin/blood*

OBJECTIVE: To carry out serological and molecular tests on 12 blood donors and family members of one proband with discrepancy results for ABO serological typing. METHODS: Twelve blood donors with ABO discrepancies identified by the Blood Center of Shaanxi Province from March 2015 to December 2023 and family members of one proband were selected as the study subjects. Serological blood typing was carried out to determine their blood phenotype. ABO genotype of the samples was determined by direct sequencing of amplicons of exons 1 to 7 and cloning sequencing of amplicons of exons 6 and 7. This study has been approved by the Ethics Committee of Blood Center of Shaanxi Province (202328). RESULTS: Serological results showed that 5 samples were Aweak, 4 samples were Aweak with anti-A1 antibody, and 3 samples were AweakB with anti-A1. Direct sequencing and cloning sequencing results showed that all 12 samples had the haplotype ABO*A1.01/c.389T>C, and family studies showed that the allele could be stably inherited. Glycosyltransferase activity in the plasma was decreased in all samples. CONCLUSION The c.389T>C variant of the ABO*A1.01 allele can alter the encoded amino acid p.Leu130Pro, which weakens the activity of A glycosyltransferase, ultimately leading to the weak expression of A antigen.
Humans ; ABO Blood-Group System/genetics* ; Blood Donors ; Alleles ; Male ; Female ; Exons ; Genotype ; China ; Adult ; Base Sequence ; Haplotypes

OBJECTIVE: To explore the regulatory mechanisms underlying the weak expression of ABO blood group antigens due to variants in the non-coding regions of the ABO gene. METHODS: From June 2014 to October 2023, a total of 29 samples from the Taiyuan Blood Center and local hospitals, which were serologically identified as having weak ABO antigen expression without detectable coding region mutations, were selected for this study. Full-length ABO gene sequencing was performed using third-generation long-read sequencing technology (Pacific Biosciences) to obtain complete haplotype sequences of the ABO gene. Variants in the non-coding regions were compared and identified to infer their regulatory effects on weak antigen expression. The procedures followed in this study were in accordance with the ethical standards of the World Medical Association's Declaration of Helsinki (2013 revision). The Medical Ethics Committee of Taiyuan Blood Center has granted an exemption from ethical review. RESULTS: 18 bp deletions in the -35 to -18 region of the promoter were identified in 7 samples. Variants in intron 1 (+5.8 kb) were detected in 7 samples, including ABO*A (28+5792_5793delCT (1 case) and ABO*B (28+5793T>C) located in the GATA binding region; ABO*B (28+5808C>T) (1 case) in the E-box region; and ABO*B (28+5875C>T) (4 cases) in the RUNX1 binding region. Nucleotide variants at splice sites were detected in 2 samples, namely ABO*B (C.98+1G>A) and ABO*B (C.204-2A>C). CONCLUSION Variants in the non-coding regulatory sequences of the ABO gene are a significant factor contributing to weak ABO antigen expression. In clinical ABO sequencing, it is essential to screen not only the conventional coding regions but also the flanking sequences, introns, and splice sites of the ABO gene to facilitate precise blood transfusion.
ABO Blood-Group System/genetics* ; Humans ; Alleles ; Promoter Regions, Genetic ; Haplotypes ; Introns

OBJECTIVE: To analyze the sequencing results, protein structure model, and impact of mutations on the dynamic stability of glycosyltransferase (GTA) in a case with Aw26 blood group subtype. METHODS: ABO phenotype was determined by serological testing (anti-A, anti-B, anti-H, and reverse typing). Potential variant of the ABO gene was identified by Sanger sequencing, and the haploid sequence of the variant site was analyzed by TOPOT-A cloning. Molecular models of the GTA was generated by PyMol, and 100-ns molecular dynamics (MD) was simulated with GROMACS software to assess the conformational stability using root mean square deviation (RMSD), radius of gyration (Rg), solvent-accessible surface area (SASA), hydrogen bonding, and binding free energy. RESULTS: Serological assays confirmed the proband as an Aw subtype, whose genotype was identified as ABO*Aw.26/ABO*O.01.02 with variants including p.Pro156Leu, p.Arg176His and p.Pro354ArgfsTer23. Haploid sequencing validated the results of direct sequencing. Molecular modeling showed that the p.Arg176His variant could reduce water-mediated hydrogen bonds from six (wild-type) to one (variant). MD simulation revealed the wild type system could achieve equilibrium within 10 ns (mean RMSD ≈ 0.30 nm), whilst the mutant system required 50 ns to equilibrate and exhibited greater fluctuation (mean RMSD ≈ 0.40 nm). Root mean square fluctuation (RMSF) analysis confirmed significantly increased flexibility in the mutant's N-terminal loop (residues 63-76). The mutant Rg displayed an expansion-contraction transition within 0 ~ 40 ns, and its SASA value has increased. The number of hydrogen bonds and binding energy of the mutant had decreased (wild-type: 5 to 8, binding energy: -11.53 kcal/mol; mutant: 2 to 5, binding energy:-8.52 kcal/mol). CONCLUSION An Aw26 subtype was identified. The p.Arg176His and p.Pro354Argfs*23p variants could synergistically compromise the structural stability of GTA and its substrate binding capacity by disrupting the hydrogen-bond network, increasing local flexibility, and reducing the overall conformational stability.
ABO Blood-Group System/chemistry* ; Humans ; Molecular Dynamics Simulation ; Models, Molecular ; Mutation ; Genotype ; Protein Conformation ; Glycosyltransferases/chemistry* ; Male

OBJECTIVE: To analyze the ABO serological and molecular characteristics of a Chinese pedigree carrying an ABO*cisAB.01 allele for the blood subgroup. METHODS: A proband undergoing blood preparation for a surgery due to an open rupture of the extensor hallucis longus tendon in the left thumb on September 5, 2024 at Weihai Central Hospital and his family members were selected as study subjects. ABO serological type of six individuals from three generations was determined by serological methods. PCR was carried out to amplify exons 6 and 7 of the ABO gene, and the amplified products were directly sequenced. Samples of the proband and his mother, son, and daughter were subjected to clone sequencing analysis. This study was approved by the Medical Ethics Committee of Weihai Central Hospital (Ethics No.: LL-2024-269-01). RESULTS: Serological testing showed that the proband and his mother were of the AB subtype, whilst his daughter was A subtype B, his father was of O, his wife was AB, and his son was A. Direct sequencing showed that the proband's genotype was ABO*cisAB.01/O.01.02, and his mother, son, and daughter had all carried an ABO*cisAB.01 allele. There were significant differences in allelic competition when the A, B and O genes were co-dominant with the cisAB.01 allele, respectively. CONCLUSION There is allelic competition between the cisAB.01 allele and different ABO alleles. Blood type serological tests combined with molecular methods and family investigations can help ascertain and interpret the ABO blood type phenotypes.
Humans ; ABO Blood-Group System/genetics* ; Male ; Female ; Phenotype ; Pedigree ; Alleles ; Genotype ; Adult ; Asian People/genetics*

OBJECTIVE: To analyze the serological and molecular biological characteristics of 5 patients with cis AB blood group, and to explore the safe transfusion strategy. METHODS: Serological identification of the samples' blood group was performed using anti-A, anti-B, anti-D, anti-A1, anti-H typing reagents and ABO reagent erythrocytes. Molecular biological identification of the samples' blood group was performed using PCR-SSP or gene sequencing. RESULTS: The serological identification results of blood group in 5 patients all showed inconsistent forward and reverse typing, presenting as A₂B₃ or A₂B_w. ABO gene sequencing of samples 1, 2 and 3 showed 261delG in exon 6 and 467C>T, 803G>C in exon 7. The genotypes of samples 1, 2 and 3 were determined to be cisAB/O . PCR-SSP genotyping was performed on sample 4 and 5，and the results were both cisAB/O . CONCLUSION Patients with cisAB alleles have inconsistent serological manifestations, and genetic testing is necessary to ensure the safety and effectiveness of blood transfusion.
Humans ; ABO Blood-Group System/genetics* ; Blood Transfusion ; Blood Grouping and Crossmatching ; Genotype ; Blood Group Antigens/genetics* ; Alleles ; Male ; Female

OBJECTIVE: By analyzing the correlation between genotypes and phenotypes, we explored the impact of the variant c.917T>C (p.L306P) in the ABO*B.01 allele on the expression and function of B-glycosyltransferase (GTB). This study aims to elucidate the molecular mechanisms underlying the occurrence of this subtype. METHODS: The study subjects included a blood donor specimen with incompatible forward and reverse ABO typing results. ABO phenotyping was determined using ABO blood group serology and GTB activity testing. Subsequently, Sanger sequencing and third-generation sequencing based on the PacBio platform were employed to sequence the ABO gene, resulting in the determination of haplotype sequences. Mutations were identified through sequence alignment. An in vitro cell expression system was established to assess the impact of the mutation site on antigen expression. RESULTS: The index case in this study was identified as B subtype with the allelic genotype c.917T>C in ABO*B.01/ABO*O.01.01 , which has not been previously reported. in vitro expression results revealed decreased levels of GTB expression and overall GTB activity in the mutant cells. Furthermore, the expression of the B antigen on the cell membrane was weaker in the mutant cells compared to the wild-type cells. CONCLUSION The p.L306P variation caused by the c.917T>C mutation in the ABO*B.01 allele may be a genetic factor contributing to the reduced expression of B antigens on the surface of red blood cells.
Humans ; ABO Blood-Group System/genetics* ; Alleles ; Genotype ; Mutation ; Glycosyltransferases/genetics* ; Haplotypes ; Phenotype