Identification and pedigree investigation of B(A) and cisAB blood groups / 中国输血杂志

【Objective】 To investigate the serological and molecular genetic characteristics of B(A) and cisAB blood groups discovered in our laboratory. 【Methods】 ABO blood group serology and genetic tests were used to identify blood groups of 6 blood samples, submitted by blood center and hospitals in Shandong, and pedigree investigation was carried on 2 of them. 【Results】 Among the 6 samples, serological results were B(A) in 5 cases and cisAB in 1 case. The results of genetic tests were consistent with the serological results, as the alleles included B(A)04, B(A)02 and cisAB01, and all genotypes were heterozygous with O. Serological pedigree study was conducted on 2 samples: One cisAB patient with his 4 relatives(cisAB type father and three O type relatives) and one B(A)02/O1 donor with his 3 relatives[ B(A) type father/brother and O type mother). For B(A)02/O1 donor, the results of genetic testing were consistent with the serological results, as the paternal genotype was the same as that of the proband, the younger brother was B(A)02/O2, and the maternal genotype was O1/O2. 【Conclusion】 The cisAB and B(A) blood groups are often indistinguishable by serological phenotypes and require genetic confirmation. CisAB pedigree investigation revealed 2 cases of cisAB blood type and B(A) pedigree investigation revealed 3 cases of B(A). The genotyping of cisAB and B(A) in this region were cisAB01/O2, B(A)02/O1, B(A)02/O2, B(A)04/O1 and B(A)04/O2. B(A)and cisAB subtypes can be accurately identified through genetic testing and pedigree investigation, which can provide a reliable basis for blood transfusion selection and ensure the safety of clinical blood transfusion.

The clinical serological characterization of cisAB and B(A) blood groups / 中国输血杂志

【Objective】 To determine the rare ABO blood subgroups rapidly and ensure the blood transfusion safety of five patients by a series of serological tests and family investigation, as their preliminary serological results of ABO blood grouping was inconsistent. 【Methods】 ABO blood grouping, antibody screening and Coombs′ tests were performed by the routine serological methods, including manual tube and automatic blood group analyzer, which had matched micro-column gel cards from Diagnostic Grifols. Polymerase chain reaction (PCR) was used to amplify the 6 and 7 exons as well as their adjacent intron region of ABO gene. The patients and their relatives′ ABO blood group and subgroup were analyzed and identified through the comparison with serological phenotype database of ABO blood group. The products of PCR were sequenced directly, and the gene mutation was identified through the comparison with the Blood Group Antigen Gene Mutation Database. 【Results】 Whether micro-column gel cards or manual tube test, the forward and reverse tests of serological grouping were not supported by each other on the five patients′ ABO blood grouping. The forward tests of patients No.1~3 showed AwB phenotype and the reverse tests showed B group. No.4 patient was the forward ABw phenotype and the reverse A group, and No.5 patient was the forward normal AB phenotype and the reverse B group, respectively. All of 5 patients′ Rh C/D/E blood grouping showed clearly; the IDT test and antibody screening result of patient No.1 was positive, while the antibody screening result of patient No.4 was negative. 【Conclusion】 The blood group serological characterization of patient No.1~3 met B(A) blood group, and patient No.4~5 met CisAB blood group. These tests can make a preliminary diagnosis of blood group phenotype, which are verified correctly via blood group genotype.

Analysis on phenotype and genotyping of CisAB subtypes: 12 Cases / 中国输血杂志

【Objective】 To analyze and master the serological and genetic characteristics of the samples with CisAB subtype and their genetic background. 【Methods】 From January 2018 to January 2022, blood samples with discrepant ABO blood typing results, from Zhengzhou voluntary blood donors and hospital patients, were subjected to phenotypic classification using micro column gel card and tube method, as well as amplification of exons 6 and 7 in ABO gene using PCR. The pedigrees of individuals with the same CisAB subtype but different serological typing results in the same family were analyzed. 【Results】 11 The forward typing of 12 samples was AB type, and unexpected antibodies against weaker antigens were found in 11 serum samples, including 9 cases with strong antigen A, 2 cases with strong antigen B, and 1 case with consistent forward and reverse typing results. Gene sequencing confirmed that 11 cases were CisAB01 subtype and 1 case was CisAB05 subtype.Among them, 7 cases had the genotype of CisAB01/O and serological phenotype of A2B3; 2 cases had the genotype of CisAB01/B and phenotype of A2B; 2 cases had the genotype of CisAB01/A and serological phenotype of A1Bx and A1B3; 1 case had the phenotype of AxB. In the CisAB01 family, 1 case of CisAB01/O with A2B3 phenotype and 1 case of CisAB01/B with A2B phenotype were detected. In the CisAB05 family, 2 CisAB05/O01 and 1 CisAB05/O02 were detected. 【Conclusion】 The serological phenotypes of different individuals in the same CisAB01 family can be different when paired with different ABO alleles. It is advisable to accurately identify the CisAB subtype genes with molecular biological methods to ensure blood transfusion safety.

Molecular analysis of an individual with CisAB phenotype / 中华医学遗传学杂志

Objective@#To explore the molecular basis for an individual with ABO subtype.@*Methods@#The ABO phenotype of the proband was determined by convention serological testing. Exons 6 and 7 of the ABO gene were subjected to PCR amplification and bi-directional Sanger sequencing. Haplotypes for exons 6 and 7 of the proband was determined using an ABO haplotype-specific amplification and sequencing technique.@*Results@#Red blood cells of the proband showed a 4+ agglutination strength with anti-A or anti-H, no agglutination reaction with anti-A1, and a 3+ agglutination strength with anti-B. His serum had no reaction with standard A cells, O cells or self cells, but was weakly reactive with B cells at 4℃. The proband was assigned as an ABO subtype based on his serological features. Bi-directional sequencing of the ABO gene revealed heterozygosity of 261 G/del, 297AG, 526CG, 657CT, 703GA, 803GC and 930GA, and homozygosity of 796CC in the proband. Haplotype-specific amplification and sequencing showed that one of his alleles was ABO*O.01.01, and another contained a c. 796A>C variation compared with the ABO*B.01 allele, which led to replacement of methionine by leucine at position 266. Searching the ABO allele database of International Society of Blood Transfusion suggested the variation to be a novel one.@*Conclusion@#The c. 796A>C variation in the ABO*B.01 allele probably underlies the CisAB subtype. Accurate identification of the ABO subtype requires combined use of serological method and genetic testing.

A Case of ABO* cis-AB01/Ax03 Found in A2B3 Phenotype / 대한수혈학회지

The cis-AB blood group is rare; however, it is relatively more common in the Korean and Japanese populations. Among nine cis-AB alleles, only the cis-AB01 allele has been reported in the Korean population. When the A2B3 phenotype is found, it has the cis-AB01/O genotype; to date, it has not been reported in any other genotype. Here we report on an extremely rare case of cis-A2B3 found in the cis-AB01/Ax03 genotype. EDTA samples of a 52-year-old male with hepatocellular carcinoma and his family were sent to our laboratory. Standard ABO typing and sequencing of exons 6 and 7 of the ABO gene of the propositus and his family were performed: the propositus with the A2B3 type had cis-AB01/Ax03, brother with O type had O01/O02, sister with O type had Ax03/O01, son with B type had Ax03/B101, and daughter with A1B3 type had cis-AB01/A102. Results based on family study and genotyping revealed that the propositus had both cis-AB01 and Ax03 alleles. This is the first case of A2B3 phenotype with cis-AB01 with an allele other than the O allele in the cis-AB blood group reported so far.

Characteristics of Intron 6 Nucleotide Sequences of cis-AB in Koreans / 대한수혈학회지

BACKGROUND: The cis-AB is a very rare phenotype in the ABO blood group system. It corresponds to a special ABO allele that encodes glycosyltransferase that is capable of synthesizing both A and B antigens. Until now, the exon 6 and 7 gene sequences of cis-AB alleles are well known. In this study, we report on the intron 6 sequence structure of the cis-AB allele. METHODS: Standard serologic tests for the ABO blood group phenotypes were performed in four cis-AB samples. Allele-separation by cloning and subsequent sequencing was carried out. RESULTS: The results showed that intron 6 of cis-AB is almost identical to the A101 allele except for three single nucleotide polymorphisms at nucleotide positions 163, 179 and 662, where the nucleotides of the A101 replace those of B101. CONCLUSION: The intron 6 sequences of cis-AB in Koreans have both A101 and B101 blood group sequences.

A Transfusion Experience for a Patient with Cis-A2B3 Phenotype / 대한수혈학회지

We report the case of a 64-year-old man presenting to the hospital for treatment of his anemia. Exact ABO blood typing is an essential step to prevent transfusion reactions. The selection of the wrong blood component for transfusion can be a clinical problem and in this case the patient had a cis-AB blood type that could have caused an ABO discrepancy. In this case neither autologous or directed blood transfusion was possible and O+ red blood cell was transfused without a transfusion reaction.

A Case of a Family with a High Frequency of cis-AB / 대한수혈학회지

The cis-AB phenotype is relatively common in the Japanese and Korean populations. Phenotypes of cis-AB include variables such as A2B3, A2B and A1B3. A few cases of cis-AB with phenotype A1 have been reported. Recently, we experienced a case with one family member identified with phenotype A1, genotype cis-AB/A and a high frequency of cis-AB. A 34-year-old woman visited the hospital for prenatal testing. The ABO phenotype of the patient was A2B3. To confirm the presence of cis-AB, ABO typing and genotyping of the patient's family were performed. The patient's mother and father were typed as normal group O and A, respectively. The ABO genotype of the mother was identified as cis-AB/A. The four sisters and brothers were typed as cis-AB. The normal incidence of cis-AB in a family is 50%. Interestingly, ABO typing revealed that all five members of the family had cis-AB in this case.

Mismatched Transfusion Reaction in cis-AB: A case report / 대한마취과학회지

AB blood group is determined by A and B genes located on each chromosome which inherited from parents. But unusual inheritance of A and B genes on the same chromosome has been reported as cis AB. Recently the authors have experienced one case of patients with cis AB blood type undergoing emergency adhesiolysis of small bowel obstruction. We transfused the patient with Rh A+ packed red blood cell and fresh frozen plasma with atypical delayed hemolytic transfusion reaction.

ABO Gene Analysis of Discrepant ABO Blood Group in Blood Donors / 대한수혈학회지

BACKGROUND: An exact ABO blood group is essential for prevention of transfusion accident and safe transfusion therapy. It is known that one of causes of ABO discrepancies is ABO subgroup caused by genetic polymorphism. Therefore, we analyzed ABO genotype of ABO discrepancies in blood donors and studied the distribution and cause of ABO discrepancies. METHODS: This study examined 118 samples showing ABO discrepancies of ABO blood typing between May 2003 and Dec 2003. ABO genotyping using the polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) method was performed on 118 samples. Restriction enzymes including BssH II, Kpn I and Alu I were used for PCR-RFLP. RESULTS: The genotypes of 118 cases were composed of 43 cases of A/B, 12 cases of A/O, 10 cases of B/O, 1 case of B/B, 37 cases of cis-AB/O, 4 cases of cis-AB/A, 11 cases of cis-AB/B. The genotype of cis-AB/O showed 32 cases with phenotype A2 B3 , 2 cases with phenotype A2 B, 2 cases with phenotype A1 B3 , 1 case with phenotype Ael B. The genotype of cis-AB/B showed 11 cases with phenotype A2 B, and cis-AB/A showed 2 cases with phenotype A2 B3 , 1 case with phenotype A1 Bx and 1 case with phenotype A1 Bel. CONCLUSION: These data demonstrated that the most frequent genotype of ABO discrepancies in our study is cis-AB. The most predominent phenotype of cis-AB/O is A2 B3 . ABO genotyping is useful in resolving ABO discrepancies, and determination of ABO subgroups.

The frequency of the cis-AB blood type in blood donors in southwestern Korea / 대한수혈학회지

BACKGROUND: Cis-AB is a rare ABO blood type with an unusual inheritance, on the same chromosome that results from a point mutation. It is relatively common in Korean and Japanese populations. Although more than 100 cases of the cis-AB blood type have been reported, there is no report on the frequency of the cis-AB blood type in Korea. Therefore, we analyzed the frequency of the cis-AB blood type in blood donors in southwestern Korea. METHODS: This study examined 111,842 samples obtained from blood donors recruited at the Gwangju-Chonnam Red Cross Blood Center between July 2002 and Oct 2002. ABO serologic tests were performed on all of the samples and ABO genotyping using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was performed on peripheral blood DNA samples from 129 cases: 24 A2B3, 81 A2B, 23 A1B3, and 1 A1Bx or el case. RESULTS: The frequency of the cis-AB blood type was 0.0331%(37/111,842). Of the 37 cases, 24 cases were the cis-AB/O genotype with the A2B3 phenotype, 9 cases were the cis-AB/A genotype with the A2B phenotype, 3 cases were the cis-AB/B genotype with the A1B3 phenotype, and 1 case was the cis-AB/A genotype with the A1Bx or el phenotype. In the 129 cases, the cis-AB ratio was 100% (24/24), 39.1% (9/23), 3.7% (3/81), and 100% (1/1) in the A2B3, A1B3, A2B, and A1Bx or el phenotypes, respectively. CONCLUSIONS: The frequency of the cis-AB blood type in blood donors in southwestern Korea is about 0.0331%. The most common type of cis-AB was cis-AB/O with the A2B3 phenotype. In addition, one case of cis-AB/A with an unusual A1Bx or el phenotype was found.

Phenotype and Genotype of Cis-AB Family in Chonnam Area / 대한수혈학회지

BACKGROUND: Cis-AB is a rare blood ABO with unusual inheritance on the same chromosome that result from a point mutation. It is relatively common in Korean and Japanese populations. We analyzed serological and molecular genetic characteristics of the family with cis-AB who had visited Chonnam National University Hospital (CNUH) for 10 years. MATERIAL AND METHODS: The subjects of this study comprised 88 samples derived from cis-AB family of 17 propositi with A2B3 phenotype diagnosed at CNUH between January 1993 and May 2002. Serologic tests for cis-AB were performed in detail on the ABO antigens of 49 samples, polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) method for cis-AB genotyping was additionally performed in peripheral blood DNA samples from 19 cases. RESULTS: The phenotypes of 49 cases were composed of 39 cases of A2B3, 7 of A2B, 2 of A1B3 and 1 of A1. ABO genotype on the blood samples from 19 cis-AB cases showed 11 cases of cis-AB/O with phenotype A2B3, 6 of cis-AB/B with phenotype A2B, 1 of cis-AB/A with phenotype A1B3 and 1 of cis-AB/A with phenotype A1. CONCLUSIONS: These data demonstrated that the most frequent type of cis-AB cases in Chonnam area was cis-AB/O with phenotype A2B3 and a case of cis-AB/A with unusual A1 phenotype was found.

A Case of Cis-AB without B Antigen Expression / 대한수혈학회지

The cis-AB bood type is a rare phenomenon in which both the A and B blood types are inherited from a single parent. The cis-AB persons are not homogeneous with respect to reactivity of their red cells to anti-A and anti-B reagents, and are split into three groups with on the basis of the strength and characteristics of the serologic reactions; these reactivities are A2B3, A1B3 and A2B. A 7-year-old Korean boy was evaluated for paternity because he was presumptively identified as blood group AweakB and known blood types of his father and mother were A. In the repeated ABO blood typing, the child was typed as group A2B3 with weak anti-B, cis-AB being suspected. Both of his mother and father were typed as group A1 in cell and serum typing. In the saliva test and adsorption and elution studies of the parents, B substance was not detected. According to ABO genotyping, the child, mother and father showed cis-AB/O, A1/O and cis-AB/A1, respectively. The paternity was confirmed, but the father had unusual expression of cis-AB genotype. This was the second case of A1/cis-AB with phenotype A1, not expressing B antigen.

Unusual Phenotype Expression in a Cis-AB Trait: Cis-AB Child from a Group A Father and a Group O Mother / 대한수혈학회지

Cis-AB (A2B3) is a rare genotype resulting from the inheritance of both A and B genes on one chromosome. Among possible genotypes of cis-AB, in individuals with O/cis AB and A1/cis-AB, the B antigen is usually weakly expressed. Study on a blood sample from a 13-year-old Korean girl showed a discrepancy between red blood cell and serum typing. The blood type was identified as AweakB on the red cell test, while weak anti-B was detected in the serum. Cis-AB (A2B3) was suspected, however, known blood types of her father and mother were A and O, respectively. In the repeated test, the propositus was typed as group A2B3. Her mother was typed as normal group O. Her father was typed as group A1 in cell typing, but in his serum, anti-B was very weakly detected. In the saliva test and adsorption and elution studies of the father, B substance was not detected. Finally, ABO genotyping was performed and ABO genotypes of the patient, mother and father were cisAB/O, O/O and cisAB/A1, respectively. This was the first reported case of A1/cisAB with phenotype A1. ABO genotyping technique will resolve problems encountered in association with unusual phenotype expression of cis-AB trait.

ABO gene analysis of cis-AB and B subgroup in blood donors / 대한수혈학회지

BACKGROUDS: Based on elucidation of genetic basis of ABO blood group, the genetic mutation of blood subgroup has been investigated. Especially, the discovery of base substitution such as C467T, G803C in cis-AB have made the efforts to determine cis-AB blood group by molecular method. This study was performed to investigate the ABO gene structure and usefulness of genotyping method in blood donors whose blood group are suspected as cis-AB and B subgroup. METHODS: Genotyping for ABO was performed in peripheral blood DNA samples from eight cis-AB donors and five B subgroup donors at red cross blood center. DNA sequencing was performed on Bint, B3 and two cis-AB samples. RESLUTS: All eight cis-AB donors showed that they have cis-AB allele and C467T substitution. Through DNA sequencing it was confirmed that cis-AB allele was derived from A allele mutation and two B subgroups showed no base sequence difference with B blood group. CONCLUSIONS: The genotyping method would be useful tool to determine blood group variants in blood donors. And more investigation is required for elucidation of genetic structure and gene expression of ABO blood subgroup.

Molecular Genetic Analysis of Cis-AB with Cytosine at nucleotide position 467 / 대한수혈학회지

BACKGROUNDS: The molecular genetic characteristcs of cis-AB blood group have shown that its allele had C, G, C and C at nucleotide positions (nps) 526, 703, 796 and 803, respectively. And all cis-AB analysed and reported molecular genetically in Korea and Japan had T at np 467 (leucine at amino acid position 156). We report a first case of cis-AB with C at np 467 (proline at amino acid position 156). METHODS: Genomic DNA was extracted from peripheral blood of cis-AB patient and amplified by DS1/DS2 and DS3/DS4 allele-specific primers. After PCR, we analysed nps 261, 467, 526, 646, 703, 796, and 803 by restriction digestion, autoradiography and automatic sequencing. RESULTS: PCR-RFLP with DS1/DS2 primers and restriction enzyme KpnI showed that cis-AB had an O allele. The results of genomic sequencing, autoradiography and restriction digestion showed that cis-AB allele at nps 467, 526, 646, 703, 796 and 803 had C, C, T, G, C and C, respectively. CONCLUSION: This cis-AB showed characteristic molecular genetic features at nps 526, 703, 796, and 803. And this is a first case of A(Pro) cis-AB with C at np 467.

Molecular Genetic Analysis of Cis-AB with Cytosine at nucleotide position 467

BACKGROUNDS: The molecular genetic characteristcs of cis-AB blood group have shown that its allele had C, G, C and C at nucleotide positions (nps) 526, 703, 796 and 803, respectively. And all cis-AB analysed and reported molecular genetically in Korea and Japan had T at np 467 (leucine at amino acid position 156). We report a first case of cis-AB with C at np 467 (proline at amino acid position 156). METHODS: Genomic DNA was extracted from peripheral blood of cis-AB patient and amplified by DS1/DS2 and DS3/DS4 allele-specific primers. After PCR, we analysed nps 261, 467, 526, 646, 703, 796, and 803 by restriction digestion, autoradiography and automatic sequencing. RESULTS: PCR-RFLP with DS1/DS2 primers and restriction enzyme KpnI showed that cis-AB had an 0 allele. The results of genomic sequencing, autoradiography and restriction digestion showed that cis-AB allele at nps 467, 526, 646, 703, 796 and 803 had C, C, T, G, C and C, respectively. CONCLUSION: This cis-AB showed characteristic molecular genetic features at nps 526, 703, 796, and 803. And this is a first case of A(Pro) cis-AB with C at np 467. (Korean J Blood Transfusion 10(1): 13-19, 1999)

Molecular Genetic Analysis of Cis-AB Blood Group in Koreans / 대한수혈학회지

BACKGROUND: Cis-AB is very rare among caucacians and found relatively often among Korean and Japanese populations. The molecular genetic characteristics of Japanese cis-AB were reported recently. All the Japanese cis-AB analyzed so far had identical polymorphisms. This work was performed to disclose the genetic polymorphisms in Korean cis-AB individuals. METHODS: DNA was extracted from 8 cis-AB Koreans. A and O transferase genes were amplified with GA0IN/GA14 allele-specific primer set, and B and cis-AB genes were amplified with GA0IN/GA13 allele-specific primer set. Restriction enzymes including BstPI, KpnI, BssHII, BsaHI, HapII, AluI, and MvaI were used for PCR-RFLP to find out the coexistence of O gene and to determine the nucleotides at nps 467, 526, 703, and 796. Exon 7 was divided into 2 regions and amplified to perform PCR-SSCP. RESULTS: All of the Korean cis-AB analyzed had identical genetic polymorphisms to those reported on Japanese cis-AB. PCR-RFLP with GA0IN/GA13 showed that all cis-AB samples had the allele with A-specific nucleotides at nps 526,703 and 796, and B-specific nucleotides at np 803. Other genetic polymorphisms showed that all of those with cis-AB allele had T at np 467 (leucine at amino acid position 156). CONCLUSION: Genetics polymorphisms reported on 29 Japanese cis-AB so far and 8 Koreans cis-AB analyzed in this study had identical mutations. This may imply that the cis-AB often found in Korea and Japan have single origin. It is plausible that a group of Korean people immigrated from the southwest part of Korea to the western part of Japan through a sea route in the past.

Study on B(A) phenotypes and identification of novel B(A)641 allele in chinese population / 中国输血杂志

C mutation. All 8 samples displayed the B(A) phenotype. Their real genotypes were B(A)/O. Conclusion Three B(A) alleles in the Chinese Han population were detected. Two alleles,B(A)700,B(A)640 were reported previously. One novel allele B(A)641, was first identified in this study.