Identification of a novel FUT1 allele in a Chinese individual featuring para-Bombay phenotype / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for an individual with a para-Bombay phenotype.@*METHODS@#A proband with mismatched forward and reverse serotypes for the ABO blood group was identified. Weakly expressed ABH blood type antigen on the surface of red blood cells was verified by absorption and release test, and the blood group substances in saliva was detected by sialic acid test. Exons 6 and 7 of the ABO gene and exons of the FUT1 and FUT2 genes were subjected to direct sequencing.@*RESULTS@#The proband was found to be of O type by forward ABO serotyping and AB type by reverse ABO serotyping, though H and substance A and B were detected in her saliva. DNA sequencing revealed that she has harbored c.35C/T, c.328G/A, and c.504delC compound heterozygous variants of the FUT1 gene. Haploid analysis showed that her FUT1 genotype was h328A/h35T+504delC, which has been uploaded to the NCBI website (No. MW323551).@*CONCLUSION@#The para-Bombay phenotype of the proband may be attributed to the novel compound heterozygous variants including c.504delC of the FUT1 gene, which may affect its function by altering the activity of FUT1 glycotransferase.

Serological Identification and FUT1 Gene Mutation Analysis of 8 Individuals with Para-Bombay Phenotypes in Guangxi / 中国实验血液学杂志

OBJECTIVE@#To study the serological characteristics and molecular biological basis of 8 individuals with Para-Bombay phenotypes in Guangxi area.@*METHODS@#Serological tests were used to identify the blood groups of red cells. Molecular biological methods, including PCR-SSP for ABO genotyping and DNA sequencing for FUT1, were used to detect the genotypes of ABO and FUT1 which determined the expression of H antigen.@*RESULTS@#Eight individuals in the study were all the Para-Bombay phenotypes, including 4 cases of B@*CONCLUSION@#There are varieties of molecular genetic mechanisms for Para-Bombay phenotypes. In this study, the FUT1 mutations that cause Para-Bombay phenotypes in Guangxi area are mainly h3, h

Sequence analysis for a case with Para-Bombay AB blood type / 中华医学遗传学杂志

OBJECTIVE@#To explore the molecular basis for a rare case with Para-Bombay AB blood type.@*METHODS@#Serological method was used to determine the blood type of the proband. Exons 6 and 7 of the ABO gene and the coding regions of FUT1 and FUT2 genes were analyzed by direct sequencing.@*RESULTS@#Serological results showed that the proband was a Para-Bombay AB subtype. His genotype was determined as ABO*A1.02/B.01. The proband was also found to harbor c.551-552delAG and c.881-882delTT of the FUT1 gene. For his four children, there were three type B and one type A, though the expression of the H type was normal.@*CONCLUSION@#The double deletions in the coding region of the FUT1 gene probably underlay the Para-Bombay blood type in the proband. Carrier of single-strand deletions may have a normal ABO phenotype.

Analysis of two novel variants of FUT1 gene in a Chinese family with para-Bombay phenotype / 中华医学遗传学杂志

OBJECTIVE@#To study rare para-Bombay blood type Bm@*METHODS@#ABO and H phenotype of the proband and her pedigree were determined with serological methods. The ABO genotype was analyzed by polymerase chain reaction-sequence specific primer(PCR-SSP). The full coding region of alpha-l,2 fucosyltransferase (FUT1) gene of the pedigree was analyzed by polymerase chain reaction and direct sequencing of the amplified fragments. The haplotype of the FUT1 gene were analyzed by cloning sequencing.@*RESULTS@#The rare para-Bombay blood type Bm@*CONCLUSION@#Two new alleles of FUT1 gene (h

Study on the Identification of Samples Mistyped as O Phenotype and the Strategy of Safe Blood Transfusion / 中国实验血液学杂志

OBJECTIVE@#To investigate the indentification method of samples mistyped as O phenotype and to explore the precision transfusion strategy.@*METHODS@#The blood samples from donors and patients admitted in our center from 2018 to 2019 was collected. The samples with O phenotype suspected subtypes were further determined by tube test, adsorption-elution test, etc. Molecular testing was used to sequence the related blood type genes of the subjects.@*RESULTS@#Among 14 subjects misjudged as O, 11 different genotypes were identified, in which 3 blood donors were Ael02/O02, Bel03/O02, and one para-Bombay with B101/O02 (FUT1: h3h3; FUT2: Se@*CONCLUSION@#The phenotypes of Ael, Bel, Aw and para-Bombay subtypes are easily misjudged as type O. Molecular technology is helpful to identify the genotype of subtypes, and the corresponding transfusion strategies could be reasonably performed.

Serological and molecular biological analysis of an individual with para-Bombay blood group due to homozygous c.948C>A variant of FUT1 gene / 中华医学遗传学杂志

OBJECTIVE@#To study the serological, molecular and genetic characteristics of an individual with para-Bombay blood group.@*METHODS@#Serological method was used to detect the presence of A, B, H antigens in red blood cells and saliva, and Sanger sequencing was used to analyze the FUT1 gene of the proband and her family members. Genetic mechanism of the blood group was analyzed by pedigree analysis.@*RESULTS@#Forward and reverse typing of the ABO blood group were inconsistent for the proband. A, B and H antigens were not found on erythrocytes, while B and H antigens were found in saliva, in addition with unexpected antibodies. The proband was found to have a genotype of ABO*B.01/ABO*O.01.04 caused by homozygous variant of c.948C>A (p.Tyr316Ter) of the FUT1 gene.@*CONCLUSION@#A novel para-Bombay blood group was identified, which was due to the missense variant of c.948C>A in the coding region of the FUT1 gene, which has probably resulted in inability to synthesis active H antigen transferase.

Molecular characterization of a recombination allele of ABO blood group / 中华医学遗传学杂志

OBJECTIVE@#To analyze the molecular characteristics of a recombinant allele of the ABO blood group.@*METHODS@#The ABO phenotype was determined with the tube method. The coding regions of the ABO and FUT1 genes were analyzed by PCR-sequence based typing. The ABO alleles of the proband were determined by allele-specific primer sequencing. The full sequences of the ABO gene of the proband and her mother were determined through next generation sequencing.@*RESULTS@#The red blood cells of the proband did not agglutinate with anti-H, and the sequence of the FUT1 gene was homozygous for c.551_552delAG.The proband was thereby assigned as para-Bombay. Bi-directional sequencing also found that she was heterozygous for c.261G/del,467C>T,c.526C>G,c.657C>T,c.703G>A,c.796C>A,c.803G>C and c.930G>A of the coding regions of the ABO gene. Allele-specific primer sequencing also found her to carry a ABO*A1.02 allele and a recombinant allele from ABO*O.01.01 and ABO*B.01. The recombination site was located between nucleotide c.375-269 and c.526, and the allele was maternally derived.@*CONCLUSION@#An recombinant allele of the ABO gene has been identified, which has originated from recombination of ABO*O.01.01 with the ABO*B.01 allele.

Gene expression profiling reveals upregulated FUT1 and MYBPC1 in children with pancreaticobiliary maljunction

Pancreaticobiliary maljunction (PBM) is associated with high risk of epithelial atypical growth and malignant transformation of the bile duct or gallbladder. However, overall changes in genetic expression have not been examined in children with PBM. Genome-wide expression was analyzed using peripheral blood samples from 10 children with PBM and 15 pediatric controls. Differentially expressed genes (DEGs) were identified using microarray. Bioinformatics analysis was conducted using Gene Ontology and KEGG analyses. The top 5 in the up-regulated genes in PBM were verified with qRT-PCR. Receiver operator characteristic curve analysis was conducted to evaluate the predictive accuracy of selected genes for PBM. The microarray experiments identified a total of 876 DEGs in PBM, among which 530 were up-regulated and the remaining 346 were down-regulated. Verification of the top 5 up-regulated genes (TYMS, MYBPC1, FUT1, XAGE2, and GREB1L) by qRT-PCR confirmed the up-regulation of MYBPC1 and FUT1. Receiver operating characteristic curve analysis suggested that FUT1 and MYBPC1 up-regulation could be used to predict PBM, with the area under the curve of 0.873 (95%CI=0.735−1.000) and 0.960 (95%CI=0.891−1.000), respectively. FUT1 and MYBPC1 were up-regulated in children with PBM, and could be used as potential biomarkers for PBM.

The balance between GMD and OFUT1 regulates Notch signaling pathway activity by modulating Notch stability

The Notch signaling pathway plays an important role in development and physiology. In Drosophila, Notch is activated by its Delta or Serrate ligands, depending in part on the sugar modifications present in its extracellular domain. O-fucosyltransferase-1 (OFUT1) performs the first glycosylation step in this process, O-fucosylating various EGF repeats at the Notch extracellular domain. Besides its O-fucosyltransferase activity, OFUT1 also behaves as a chaperone during Notch synthesis and is able to down regulate Notch by enhancing its endocytosis and degradation. We have reevaluated the roles that O-fucosylation and the synthesis of GDP-fucose play in the regulation of Notch protein stability. Using mutants and the UAS/Gal4 system, we modified in developing tissues the amount of GDP-mannose-deshydratase (GMD), the first enzyme in the synthesis of GDP-fucose. Our results show that GMD activity, and likely the levels of GDP-fucose and O-fucosylation, are essential to stabilize the Notch protein. Notch degradation observed under low GMD expression is absolutely dependent on OFUT1 and this is also observed in Notch Abruptex mutants, which have mutations in some potential O-fucosylated EGF domains. We propose that the GDP-fucose/OFUT1 balance determines the ability of OFUT1 to endocytose and degrade Notch in a manner that is independent of the residues affected by Abruptex mutations in Notch EGF domains.

Estudio de las variantes alélicas del gen FUT2 en una población de Rosario, Santa Fe / Allele of FUT2 gen variables in a population of Rosario, Argentina

El estado secretor de un individuo está determinado por el gen Secretor (FUT2), responsable de la presencia de antígenos ABH en las secreciones del organismo. El polimorfismo del gen FUT2 muestra una gran variabilidad dependiente del tipo de población. Alrededor del 20% de los individuos caucásicos son no­secretores y presentan la mutación G428A. El objetivo de este trabajo fue estudiar las variables alélicas del gen FUT2 en una población de Rosario. Se trabajó con muestras de sangre periférica de dadores voluntarios (n=1728). Se determinó el estado secretor en plasma y saliva y el fenotipo Lewis. El ADN genómico fue extraído por la técnica de salting-out modificada y fue analizado por ASA-PCR con cebadores específicos para el alelo G428A y para el alelo wild type del gen FUT2. Los resultados obtenidos mostraron que el 77% de los individuos investigados fueron secretores y presentaron el fenotipo Lewis Le(a-b+). El polimorfismo G428A estuvo presente en homocigosis en un 7.5%, valor menor al reportado en la bibliografía para la población caucásica. El análisis molecular del gen FUT2 confirmaría la diversidad genética de la población investigada y podría ser utilizada como un marcador poblacional.

The secretor status is determinate by the secretor gene (FUT2) responsible of the ABH antigens expression in human secretions. About 20% of Caucasian individuals are non-secretors. The aim of this study was to study the allelic varieties of the FUT2 gene by a PCR reaction. We worked with peripheral blood samples of volunteers (n= 1728). We determinated the secretor status in plasma and saliva. The genomic DNA was extracted by an enzymatic digestion method and was analyzed by ASA-PCR with specific primers for the G428A allele and for the wild type allele of the FUT2 gene. The results obtained by serologic and molecular methods showed that the 77% of the investigate individuals were secretors. The G428A polymorphism had present in a 7.5%. The allelic varieties of the other non-secretor individuals different to the G428A might to correspond to other mutations. The molecular analysis of the FUT2 gene confirms the genetic diversity of the investigated population.

Polymorphic distribution of FUT2/01 in northern Han Chinese population / 法医学杂志

OBJECTIVE@#To investigate the sequence features of FUT2/01 locus and its polymorphic distribution in Chinese population, and to discuss its application potential in forensic medicine.@*METHODS@#The alleles on FUT2/01 locus were amplified by PCR and then were sequenced. Furthermore, polymorphic distribution of the locus was analyzed by polyacrylamide gel electrophoresis. The genotypes were characterized with fluorescence labeling followed by automatic detection system.@*RESULTS@#The sequencing results only showed the length differences which were determined by the tandem repeats variance of the core sequence. There were 9 alleles and 28 genotypes identified from 162 individuals. The discrimination power and excluding probability of paternity were 0.9639 and 0.6266, respectively. In addition, the locus could be genotyped by automatic analysis very well.@*CONCLUSION@#The FUT2/01 locus exhibits high heterozygosity and individual identification power in Chinese Han population, and may be a valuable STR system for application in forensic medicine.