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 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

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

OBJECTIVE: To analyze the B_el 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.
Point Mutation ; Alleles ; ABO Blood-Group System/genetics* ; Exons ; Introns ; Genotype ; Humans ; Male ; Female ; Glycosyltransferases/genetics*

OBJECTIVE: To identify the blood type of specimens from pregnant patients with difficult-to-type ABO status, and to guide clinical safe blood transfusion. METHODS: The specimens from 36 pregnant patients with suspicious ABO blood group were collected. These specimens were submitted by clinical institutions from various regions to our center's genetic testing platform from January 2021 to December 2022. The blood group phenotypes and genotypes of these specimens were identified by serological method and genetic sequencing. RESULTS: A total of 20 ABO subtypes were detected in the 36 samples, including 10 cases of BA/O, 3 cases of cisAB/O, 2 cases of A/Bw, 1 case of A2/B, 1 case of Aw/B, 1 case of BA/B, 1 case of BA/A, and 1 case of Bw/O. Additionally, 4 cases were identified as para-Bombay blood type, and no specific variations associated with abnormal phenotypes were found in the remaining 12 cases. CONCLUSION ABO subtypes interfere with ABO blood group identification in pregnant patients, and pregnancy status also affects blood group phenotype. Accurate determination of blood group genotype by genetic sequencing technology can guide clinical blood transfusion for pregnant patients, and ensure maternal and infant safety.
Humans ; Female ; Pregnancy ; ABO Blood-Group System/genetics* ; Blood Grouping and Crossmatching ; Blood Transfusion ; Genotype ; Phenotype

OBJECTIVE: Serological and molecular biological analysis of a B(A) subtype family was carried out to explore the underlying mechanism of B(A) subtype and clinical safe blood transfusion strategies. METHODS: The ABO blood type of the proband and her four family members were identified by serological methods, and serological experiments such as anti-H, anti-A1 and absorption-elution tests was added. In addition, the exons 6 and 7 of the ABO gene were sequenced by PCR-SSP (polymerase chain reaction - sequence specific primer). RESULTS: The serological results showed that the agglutination intensity of the proband, her mother and her maternal grandmother was imbalanced during forward typing, showing weak A and strong B antigens, and there were strong H antigens and their intensity were higher than that of normal B type. The results of reverse typing indicated the presence of weak anti-A1 antibodies, and human anti-A was positive in the absorption-elution test. Genetic sequencing revealed a characteristic mutation of c.700 C>G in all three individuals. The sequencing results showed that the proband was B(A)02/B01, her mother was B(A)02/O02, and her maternal grandmother was B(A)02/O01 . According to the compatibility principle, 1.5 units of type O washed red blood cells were transfused intraoperatively, resulting in no adverse reactions. CONCLUSION The c.700 C > G mutation on exon 7 is the molecular basis for the formation of B(A)02, and pedigree analysis shows that the B(A)02 allele was inherited from the proband's maternal grandmother to the proband's mother and then to the proband, showing a stable cis-inheritance pattern rather than a spontaneous mutation. For patients with B(A)02 subtype, type O washed red blood cells and type AB plasma can be transfused according to the principle of compatibility.
Humans ; ABO Blood-Group System/genetics* ; Female ; Blood Transfusion ; Blood Grouping and Crossmatching ; Pedigree ; Male ; Mutation ; Adult ; Exons

OBJECTIVE: To study the characteristics of a novel variant of the α-1,3-N-acetylgalactosaminyltransferase gene in a family through serological and gene sequence analyses of a proband with ABO subtype and her family members. METHODS: Blood samples of the proband and four family members were collected. The ABO phenotypes were detected by serological methods, and the ABO blood group genotyping was performed by fluorescence PCR. Direct sequencing was carried out for exons 1-7 of the ABO gene in the proband and family members, and cloning sequencing was conducted for exons 6 and 7. RESULTS: The serological test showed that the blood group phenotype of the proband was Ael type, and the ABO blood group genotyping result was A/O. Sequencing results indicated that on the basis of the ABO*A1.01 sequence, there were simultaneous variations of c.467C>T and c.664G>A in exon 7 of the A allele, which belonged to a novel variation of the A allele and had been registered in GenBank with the accession number MZ076784.1. Family investigation revealed that the proband, her son and granddaughter all had this novel variation. CONCLUSION On the basis of the ABO*A1.01 sequence, the new variation of the combination of c.467C>T and c.664G>A in exon 7 is a heritable variation. It is speculated that this variation is the cause of the weakened expression of the A antigen.
Humans ; N-Acetylgalactosaminyltransferases/genetics* ; ABO Blood-Group System/genetics* ; Pedigree ; Female ; Genotype ; Male ; Exons ; Alleles ; Phenotype

OBJECTIVE: The molecular biology of alleles of ABO blood group A_el and B_el subtype from two samples was analyzed to explore the effect of mutations on the structure of glycosyltransferase. METHODS: The ABO phenotypes were identified by serological techniques, then exons 6 and 7 of ABO gene were amplified and sequenced, combined with haplotype analysis to determine the genotypes. Finally, homology modeling of the mutated A/B glycosyltransferase were conducted by Modeller software and the effect of mutations on the spatial structure was analyzed by PyMol software. RESULTS: The serological phenotypes of the two samples were A_el and B_el, and their genotypes were ABO*AW.37/ABO*O.01.01 and ABO*BEL.03/ABO*O.01.01, respectively. The three-dimensional structure modeling of the protein showed that, compared to the wild-type glycosyltransferase, two hydrogen bonds between the side chain of p.Glu314 and surrounding amino acid disappeared in the p.Lys314Glu mutant GTA; the hydrogen bonds between the side chain of p.Trp168 and surrounding amino acid also disappeared, and the hydrogen bond between the main chain of p.Trp168 and p.Gly165 was shortened to 3.3 Å in the p.Arg168Trp mutant GTB. CONCLUSION Mutations in exon 7 of ABO gene c.940A>G and c.502C>T are keys to the formation of AW.37 and BEL.03 alleles, resulting in decreased expression of A and B antigens, respectively.
ABO Blood-Group System/classification* ; Humans ; Genotype ; Mutation ; Alleles ; Glycosyltransferases/genetics* ; Exons ; Haplotypes ; Phenotype ; Models, Molecular

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