OBJECTIVETo probe into the molecular genetics basis for para-Bombay phenotype.

METHODSRed blood cell phenotype of the proband was characterized by serological techniques. Exons 6 and 7 of ABO gene, the entire coding region of alpha(1,2) fucosyltransferase (FUT1) gene and FUT2 gene were amplified by polymerase chain reaction (PCR) from genomic DNA of the proband respectively. The PCR products were excised and purified from agarose gels and were directly sequenced.

RESULTSAG at 547-552 deletion homozygous allele was found in the proband, which caused a reading frame shift and a premature stop codon. Parents of proband were heterozygous carriers.

CONCLUSIONTwo base deletion at position 547-552 of alpha (1,2) fucosyltransferase gene may cause para-Bombay phenotype.

Adolescent ; Fucosyltransferases ; genetics ; Gene Rearrangement ; Humans ; Leukemia, Myeloid, Acute ; genetics ; Male ; Protein-Tyrosine Kinases ; genetics

OBJECTIVETo study genetic characteristics of an individual with para-Bombay phenotype and her family members.

METHODSABO and H antigens were detected with routine serological techniques.The entire coding region of FUT1 gene was amplified by polymerase chain reaction (PCR). PCR products was purified with enzymes digestion and directly sequenced.

RESULTSThe RBCs of the proband did not agglutinate with H antibody. The proband therefore has a para-Bombay phenotype (Bmh). Direct sequencing indicated the FUT1 sequence of the proband contained a homozygous 547-552 del AG and heterozygous 814A>G mutation, which gave rise to two haplotypes of 547-552delAG, 547-552delAG and 814A>G. The ABO blood type of the proband' s mother and sisters were all B.Sequencing of the FUT1 gene has found heterozygous 547-552 del AG, 814A>G mutations in the mother and elder sister, and heterozygous 547-552 del AG mutation in her younger sister. The FUT1 547-552 del AG and 814 A>G mutations of the proband were inherited from her mother.

CONCLUSIONA complex mutation of the FUT1 gene consisting of 547-55 del AG and 814 A>G has been identified in an individual with para-Bombay phenotype.

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
ABO Blood-Group System/genetics* ; China ; Female ; Fucosyltransferases/genetics* ; Genotype ; Humans ; Phenotype

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.
ABO Blood-Group System/genetics* ; Alleles ; Fucosyltransferases/genetics* ; Genotype ; Humans ; Male ; Phenotype ; Sequence Analysis

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
ABO Blood-Group System/genetics* ; Alleles ; China ; Fucosyltransferases/genetics* ; Genotype ; Humans ; Mutation ; Phenotype

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.
ABO Blood-Group System/genetics* ; Alleles ; Female ; Fucosyltransferases/genetics* ; Genotype ; Homozygote ; Humans ; Phenotype

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.
ABO Blood-Group System ; Alleles ; Blood Transfusion ; Fucosyltransferases/genetics* ; Genotype ; Humans ; Phenotype

OBJECTIVE: To explore the molecular basis for an individual with para-Bombay phenotype of the H blood group. METHODS: Intron 5 to 3'-UTR of the ABO gene and exon 4 of the FUT1 gene were amplified with PCR and subjected to direct sequencing. Mutations of the FUT1 gene were identified by TOPO cloning sequencing. RESULTS: Direct sequencing showed that her ABO genotype was B101/O01. TOPO cloning sequencing found that this individual had three mutations of the FUT1 gene, including an heterozygous AG deletion (CAGAGAG→CAGAG) at position 547 to 552, and two C→T mutations at positions 35 (C35T) and 293 (C293T) on the other homologous chromosome. The two alleles comprised a new recombination of mutations c.35T>C and c.293C>T, and the sequence has been submitted to NCBI (No. MG597611). CONCLUSION A novel combination of FUT1 alleles with c.35 C>T and c.293C>T has been identified in an individual with para-Bombay phenotype.
ABO Blood-Group System ; Alleles ; Female ; Fucosyltransferases ; genetics ; Genotype ; Humans ; Phenotype

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.
ABO Blood-Group System/genetics* ; Alleles ; China ; Female ; Fucosyltransferases/genetics* ; Genotype ; Humans ; Phenotype