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

No abstract available.
ABO Blood-Group System/*genetics ; Alleles ; Asian Continental Ancestry Group/*genetics ; Base Sequence ; DNA/chemistry/isolation & purification/metabolism ; Female ; Genotype ; Humans ; Middle Aged ; Pedigree ; Polymerase Chain Reaction ; Polymorphism, Single Nucleotide ; Republic of Korea ; Sequence Analysis, DNA

BACKGROUND: Detection methods for ABO antibody (Ab) titers vary across laboratories, and the results are different depending on the method used. We aimed to compare titer values using different detection methods for the measurement of ABO Ab titers. METHODS: For ABO Ab detection, pooled group A or B red blood cells (RBCs) were reacted with each of 20 sera from blood groups A, B, or O without dithiothreitol treatment. The room-temperature (RT) incubation technique and the indirect antiglobulin test (IAT) were used in the tube test and gel card test. Flow cytometry (FCM) was performed by using anti-IgM and anti-IgG Abs. RESULTS: Regardless of the blood groups tested, the FCM assay with anti-IgM showed the highest titer compared to the tube test and gel card test with RT incubation in both. The tube test with IAT showed a higher titer than the gel card test with IAT (Gel-IAT) or FCM with anti-IgG in blood group A and B, while Gel-IAT showed the highest titer relative to the other tests, only for the anti-A Ab in blood group O. CONCLUSIONS: There were significant differences in the titers depending on the detection method used, and each method showed a different detection capacity for each ABO Ab depending on the ABO blood group tested. Therefore, caution should be exercised in interpreting ABO Ab titer results, taking into consideration the detection method used and the blood group.
ABO Blood-Group System/*immunology ; Adult ; Aged ; Agglutination Tests/instrumentation/*standards ; Antibodies/*analysis ; Antibodies, Anti-Idiotypic/analysis ; Erythrocytes/chemistry/metabolism ; Female ; *Flow Cytometry ; Humans ; Male ; Middle Aged ; Temperature

This study was aimed to investigate the impact of vWF A1381T polymorphism (rs216311) and ABO blood group on von Willebrand factor level in plasma. 120 healthy volunteers, aging from 19 to 33 years (average 24) were recruited. The vWF:Ag level in plasma was determined by ELISA. vWF gene A1381T polymorphisms were analyzed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequenced when necessary. The data were grouped by gender, blood group and/or genotype. The difference of plasma vWF level between male and female were analyzed by independent sample t test. One way ANOVA were used to analyze the difference of vWF level in each blood group of genotype while factorial design ANOVA were used to test the difference of vWF level in plasma between A1381T genotype and/or ABO blood groups. The results showed that analysis of plasma vWF level in 120 volunteers of both male (60) and female (60) demonstrated no statistical difference (t = 1.039, p = 0.301). The vWF level was lower in blood type O group than that in non-O group (p < 0.001); the plasma vWF level in AA mutant of vWF A1381T gene polymorphism was lower than that in AG and GG mutant (p = 0.003 and 0.019, respectively). In blood type O group, the vWF plasma level in AG mutant of vWF A1381T gene polymorphism resulted in non-difference (p = 0.070) compared with AA or AG mutant, while there was significant difference in vWF of plasma level when contrast tests were applied (t = 2.321 and p = 0.028, respectively). In non-O group, the plasma vWF level in AG mutant of vWF A1381T gene polymorphism were significantly different from AA mutant (p = 0.032). It is concluded that plasma vWF level unrelated with gender but interrelates with ABO blood groups. Plasma vWF level in vWF gene A1381T polymorphism with AA mutant is significantly lower than that with AG and GG mutant. In blood type O group, plasma vWF level in vWF gene A1381T polymorphism with AG mutant is higher than that with AA and GG mutant. In non-O group, the vWF plasma level in A1381T gene polymorphism with AG mutant is significantly higher than that with AA mutant. This change may be beneficial to understand some diseases, especially cardio-cerebral vascular diseases.
ABO Blood-Group System ; genetics ; Adult ; Blood Grouping and Crossmatching ; Female ; Genotype ; Humans ; Male ; Plasma ; chemistry ; Polymorphism, Genetic ; Young Adult ; von Willebrand Factor ; analysis ; genetics

In order to elucidate the expression and molecular genetic background of ABO gene seven samples with ABO discrepancy further identified as bi-specific ABO gene were studied. All these samples were subjected to phenotyping by monoclonal and polyclonal antisera and were then genotyped by direct DNA sequencing and haplotype-sequencing at the exon 6 and 7 of ABO gene. As a result, six ABO dual-specific alleles were identified in Chinese population. An antigen expressed by these B (A) or Cis-AB individuals varied from very low level to the normal level, compared with common A blood group samples. In conclusion, molecular genetic backgrounds of two pairs out of four samples in all samples were the same, however, the ABO expression showed diverse.
ABO Blood-Group System ; genetics ; Asian Continental Ancestry Group ; genetics ; DNA Mutational Analysis ; Erythrocytes ; cytology ; enzymology ; metabolism ; Exons ; genetics ; Glycosyltransferases ; chemistry ; genetics ; Humans

OBJECTIVE: ABO genotyping for forensic identification by oligonucleotide chip. METHODS: Oligonucleotide microarrays which could detect 3 different SNPs in exon 6 and exon 7 for ABO genotyping were used. Population studies on ABO was carried out in a sample of 115 unrelated Chinese Han individuals. The method was also applied to cases. RESULTS: The technique could identify 6 genotypes of ABO system. According to the results of population studies, no significant deviations from Hardy-Weinberg equilibrium could be found. The observed and expected heterozygosities were 0.591 and 0.616 respectively. The polymorphic information content was 0.544. The average exclusion probabilities in buos and trios was 0.188 and 0.344 respectively. The discrimination power is 0.777. CONCLUSION The data and case application demonstrated that ABO typing by oligonucleotide probe arrays was a useful technique for paternity testing and individual identification.
ABO Blood-Group System/genetics* ; Blood Stains ; DNA/blood* ; DNA Primers ; Female ; Forensic Medicine ; Genotype ; Hair/chemistry* ; Humans ; Oligonucleotide Array Sequence Analysis