Genotyping of the rare Para-Bombay blood group in southern Thailand

ABSTRACT Introduction: The para-Bombay phenotype, or H-deficient secretor, results from different mutations of the FUT1, with or without the FUT2 mutation. Consequently, there is an absent or weak expression of the H antigen on red blood cells (RBCs). Routine ABO blood grouping for two siblings with blood group O showed discrepant results with their parental blood group AB. Fragments encompassing the entire coding region of the FUT1 and FUT2 genes were investigated. Methods: Blood and saliva specimens were collected to verify the correct ABO grouping by cell grouping, serum grouping and the hemagglutination inhibition (HI) test, respectively. The FUT1 and FUT2 genomes were identified using the whole-exome sequencing (WES) in two children's DNA blood specimens and may have caused, or been relative to, their blood group. Genetic variations of the FUT1 and FUT2 genes have been investigated in the other family members using the Sanger sequencing. Results: The serologic reaction results of the proband revealed that A, B and H antigens were absent on RBCs, and that the serum contained anti-H. However, ABH and AH antigens were present in the saliva PB1 and PB2, respectively. The probands PB1 and PB2 were assigned as AB and A blood groups, respectively. Blood genotyping confirmed that heterozygous mutations of the FUT1 gene, c.551_552delAG, were identified. Three family members, PB3, PB, and PB8, also showed normal ABO blood groups, but their genotypes were also the FUT1 mutation c.551_552delAG. Conclusions: The FUT1 mutation c.551_552delAG may result in the reduced or absent H antigen production on RBCs, which characterizes the para-Bombay phenotypes. Blood genotyping is essential if these individuals need a blood transfusion or are planning to donate blood.

Molecular genetic analysis and predigree of a new FUT1 allele of para-Bombay blood group: a case report / 中国输血杂志

【Objective】 To study the serological and molecular mechanism of a case of para-Bombay blood group caused by 236delG mutation of FUT1 gene and investigate the pedigree. 【Methods】 The ABO, H and Lewis antigens of the proband and her family members were detected serologically, and the ABO blood group was confirmed by gene testing. The FUT1 gene was amplified by PCR and then sequenced. The structure of FUT1 236delG enzyme of the proband was simulated in 3D by SwissModel online server. 【Results】 Serological results showed that the proband was rare para-Bombay ABhm, Le(a-b-). Her father and mother was type A and type B, respectively. The gene results showed that the proband was type AB, while her father and mother was type A and type B, respectively. The sequencing results showed that the proband had 236delG/551_552delAG gene mutation, while her mother had 236delG FUT1 gene mutation, and her father had 551_552delAG FUT1 gene mutation. The 3D simulation of the enzyme structure of the proband FUT1 236delG showed that the translated product was an alpha helix structure with no actual function. 【Conclusion】 The 236delG mutation is a new discovered mutation in FUT1 genotype, with 551_ 552delAG mutation(FUT1* 01N.06 genotype), which can result in the generation of para-Bombay blood group.

Effect and mechanism of terminal fucosylation inhibitor on ciclosporin-induced renal epithelial-mesenchymal transition / 器官移植

Objective To evaluate the effect and mechanism of terminal fucosylation inhibitor 2-deoxy-D-galactose (2-D-gal) on ciclosporin (CsA)-induced renal epithelial-mesenchymal transition (EMT). Methods Fifteen male C57BL/6 mice aged 8-10 weeks were randomly and evenly divided into the control group (Ctrl group), CsA group and CsA+2-D-gal group (n=5). The expression levels of fucosyltransferase 1 (FUT1), EMT-associated proteins including E-cadherin, Vimentin, α-smooth muscle actin (α-SMA) in the kidney tissues of the Ctrl and CsA groups were detected by Western blot. The expression levels of terminal fucose in the kidney tissues of Ctrl and CsA groups were determined by immunofluorescence. The renal fibrosis of mice in each group was evaluated by Masson staining. The blood urea nitrogen and serum creatinine levels of mice in each group were detected. The in vitro EMT model of renal tubular epithelial cell HK2 was induced by CsA. HK2 cells were stimulated with 0, 2.5, 5.0 and 10.0 μmol/L CsA for 24 h, respectively. In addition, HK2 cells were divided into the Ctrl, 2-D-gal, CsA and CsA+2-D-gal groups. The morphology of HK2 cells after stimulation with different concentrations of CsA and in each group was observed. The expression levels of FUT1, E-cadherin, Vimentin and α-SMA in HK2 cells after stimulation with different concentrations of CsA and in each group were detected by Western blot. The expression level of terminal fucose in HK2 cells of the Ctrl and CsA groups was measured by immunofluorescence. Results Compared with the Ctrl group, the relative expression of E-cadherin protein was down-regulated, those of FUT1, Vimentin and α-SMA proteins were up-regulated (all P < 0.05), and that of terminal fucose in the mouse kidney tissues was up-regulated in the CsA group. Compared with the Ctrl group, the blood urea nitrogen and serum creatinine levels in the CsA and CsA+2-D-gal groups were up-regulated (all P < 0.05). Compared with the CsA group, the blood urea nitrogen and serum creatinine levels in the CsA+2-D-gal group were down-regulated (both P < 0.05). Compared with the Ctrl group, the collagen fiber deposition was increased and the relative expression of α-SMA protein was up-regulated in the mouse kidney tissues of CsA and CsA+2-D-gal groups (all P < 0.05). Compared with the CsA group, the collagen fiber deposition was decreased and the relative expression of α-SMA protein in the mouse kidney tissues was down-regulated in the CsA+2-D-gal group (both P < 0.05). With the increase of CsA concentration, the morphology of HK2 cells gradually became longer and thinner from original normal cobblestone shape, the relative expression levels of FUT1, Vimentin and α-SMA protein in HK2 cells were up-regulated, and that of E-cadherin protein was down-regulated in a concentration-dependent manner. Compared with the Ctrl group, the expression level of terminal fucose of HK2 cells was up-regulated in the CsA group. After CsA treatment combined with 2-D-gal intervention, the morphology of HK2 cells in the CsA+2-D-gal group was restored to resemble that of normal HK2 cells. Compared with the CsA group, the relative expression of E-cadherin protein in HK2 cells was up-regulated, whereas those of Vimentin and α-SMA proteins were down-regulated in the CsA+2-D-gal group (all P < 0.05). Conclusions CsA may induce EMT both in vivo and in vitro, and the terminal fucosylation is increased. 2-D-gal may inhibit CsA-induced EMT by suppressing the terminal fucosylation.

Study on molecular mechanism and pedigree investigationof para-bombay blood group caused by rare mutations at position h235 and position h649 of FUT1 gene / 中国输血杂志

【Objective】 To study the molecular mechanism of para-bombay blood group caused by two rare mutation combinations and investigate the pedigree. 【Methods】 ABO and H antigens were detected by serological test, and the ABO blood group was confirmed by gene detection; the FUT1 gene was amplified by PCR and sequenced. 【Results】 Serological results showed that the proband was a rare para-bombay blood Bhm, Le(a-b+ ), and the proband′s parents were both B Le (a-b + ). The sequencing results showed that the proband and his mother had mutation at h235 G→C of FUT1 gene. Proband and his father had mutation at h649 G→T of FUT1 gene. 【Conclusion】 The combination of two rare mutations resulted in the formation of a para-bombay phenotype, which is helpful to clarify the gene polymorphism and genetic heterogeneity of para-bombay phenotype, providing data support and theoretical basis for its blood group identification and safe and reasonable blood use of para-bombay phenotype.

The First Case of Para-Bombay Blood Type Encountered in a Korean Tertiary Hospital

Para-Bombay phenotypes are rare blood groups that have inherent defects in producing H antigens associated with FUT1 and/or FUT2. We report the first case of para-Bombay blood type in a Southeast Asian patient admitted at a tertiary hospital in Korea. A 23-year-old Indonesian man presented to the hospital with fever and was diagnosed with a disseminated nontuberculous mycobacterium infection and anemia. During blood group typing for blood transfusion, cell typing showed no agglutination with both anti-A and anti-B reagents. Serum typing showed strong reactivity against B cells and trace agglutination pattern with A1 cells. His red blood cells failed to react with anti-H reagents. Direct sequencing of FUT1 and FUT2 revealed a missense variation, c.328G>A (p.Ala110Thr, rs56342683, FUT1*01W.02), and a synonymous variant, c.390C>T (p.Asn130=, rs281377, Se³⁵⁷), respectively. This highlights the need for both forward and reverse grouping.

Serological characteristics and gene mutation analysis of Para-Bombay blood group / 军事医学

Objective To identify the Para-Bombay blood group on the basis of its serological characteristics .Methods ABO blood typing , H antigen detection , absorption and elution test , and saliva neutralization test were conducted for serological identification of ABO blood group .PCR-SSP was used to sequence FUT1 and FUT2 genes.Results Results of ABO genotyping of eight individuals of the Para-Bombay blood group were consistent with results of their serological blood typing.Among these cases, there were 3 cases of Amh,4 cases of Bmh,and 1 case of Abmh.The results of their FUT1 genotyping were h1h1 in 3 cases, h2h2 in 2 cases and h1h2 in 3 cases.Conclusion The differentce of agglutination intensity between Ac and Bc in reverse ABO blood typing and abnormal Oc agglutination is of greet significance for Para -Bombay blood group.

Molecular genetics analysis and frequency survey of H deficient phenotype / 中国输血杂志

Objective To survey the frequency of H deficient phenotype in blood donor population and analyze the serological and genetic characteristics of these individuals.Methods The H deficient phenotype was screened with anti-H monoclonal antibody.The ABO type was screened with serological method and with sequence specific primer polymerase chain reaction(PCR-SSP).FUT1 and FUT2 gene sequences were analyzed with direct sequencing of PCR products and gene cloning products.Result Of 85 390 blood donors,ten individuals were identified to be para-Bombay phenotype.Four h alleles were found in 14 para-Bombay phenotype individuals,h1(nt547-552?ag),h2(nt880-882?tt),h3(nt658c→t),and h_(new-2)(nt328g→a).The FUT1 genotypes of these para-Bombay individuals were h1/h1(6 individuals),h1/h2(7 individuals) and h3/h_(new2)(1 individual),and the frequency of 4 allele were 67.85%(h1),25%(h2),3.57%(h3),and 3.57%(h_(new-2)),respectively.FUT2 gene was analyzed in 12 para-Bombay phenotype individuals,and a mutation of nt357c→t was detected in all FUT2 gene,another mutation of nt716g→a were heterozygous in 5 individuals with h1/h2 genotype.No null FUT2 gene was detected.In serological analysis,all atypical anti-A or anti-B antibody of 14 para-Bombay individuals were inactive at 37℃,7 individuals had active anti-H antibody at 37℃.Conclusion The frequency of H deficient phenotype in Fujian population is about 1:8 500.The h1 and h2 alleles are predominant in Fujian H deficient individuals on h1-Se~(357) and h2-Se~(357,716) haplotype background.

Mutational analysis of FUT1 and FUT2 genes in para-Bombay individuals / 中国输血杂志

Objective To study the mutation of FUT1 and FUT2 genes in para-Bombay individual.Methods Direct DNA sequencing of FUT1 and FUT2 gene coding region were analyzed in two individuals with para-Bombay phenotype.Results One individual lost one of the three AG repeats located at nucleotides 547~552 of the FUT1 gene, whereas two of the three T repeats located at nucleotides 880~882 were deleted in the other.Conclusion Two frame-shift mutations of FUT1 gene are responsible for the H antigen deficiency