The serological and genetic basis of the cis-AB blood group in Korea

BACKGROUND AND OBJECTIVES: The cis-AB blood group is rare, although relatively common amongst Koreans. The serological characteristics and genetic basis of Korean cis-AB blood donors were investigated. MATERIALS AND METHODS: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), designed to detect the cis-AB01 allele, was performed on 194 AB samples which demonstrated weak or unusual expression of either or both of the A or B antigens. RESULTS AND CONCLUSIONS: Sixty cis-AB01 donors were identified. cis-AB01/O01 or O02 were the most common genotypes (36/60) detected only in A(2)B(3) donors, and cis-AB01/B101 (nine of 60) was the least common genotype identified only in A(2)B donors. Surprisingly cis-AB01/A102 (15/60) was identified in a variety of phenotypes (A(1)B(3), A(1)B(x) or el, A(int)B(3)).     

A novel B(var) allele (547 G>A) demonstrates differential expression depending on the co-inherited ABO allele

BACKGROUND AND OBJECTIVES: Genetic analysis of group B donors in Korea was performed. MATERIALS AND METHODS: Exons 6 and 7 were sequenced in 12 phenotypically B3 donors 6 B3, 6 A1B3. RESULTS: Consensus sequences all B3 and 2/6 A1B3 donors were present. Four A1B3 donors demonstrated a novel B allele, B(var), in the context of A101/ or A102/B(var) genotypes. Family studies based on an A1B3 donor with the B(var) allele and on another unrelated subject with identical genotype and phenotype revealed B(var)/O01 genotypes with full B-antigen expression. CONCLUSIONS: B(var) allele is subject to differential expression, depending on the co-inherited ABO allele.     

Association of ABO gene mutations resulting in a rare B subgroup

BACKGROUND AND OBJECTIVES: B subgroups are rare and the genetic analysis reported to date has been limited. MATERIALS AND METHODS: Serological and molecular investigations were performed in blood from a B-subgroup donor. RESULTS: Red cells did not react with anti-B and anti-AB reagents. However, cells absorbed anti-B. Red cells presented positive reactions with anti-H, and saliva secreted H substance. The molecular study demonstrated a B allele with the substitutions 467C>T, 646T>A, 681G>A, 771C>T, 796C>A, 803G>C, 829G>A and an O allele with the sequence of O02. CONCLUSIONS: It is probable that the presence in exon 7 of some of the O02 substitutions could have weakened the enzymatic activity of the encoded B transferase.     

Molecular Genetic Analysis of the ABO Blood Group System: 4. Another Type of O Allele

We have encountered an allele which seems to be another type of O allele at the human histo-blood group ABO locus. We have determined the nucleotide sequence of this allele over the coding region in the last two coding exons. This allele does not possess the single-nucleotide deletion found common among all the O alleles previously analyzed. Compared with A¹ allele, this allele has three nucleotide substitutions resulting in two amino acid substitutions. The introduction of these amino acid substitutions into the A¹ transferase expression construct apparently abolished the enzymatic activity of A¹ transferase.     

A functional promotor polymorphism of TNF-alpha is associated with primary gastric B-Cell lymphoma

BACKGROUND AND AIMS: The host genetic background to develop primary gastric B-cell lymphoma in patients with chronic Helicobacter pylori infection is unknown. Tumor necrosis factor (TNF)-alpha plays a key role in H. pylori-associated inflammation and appears to be involved in the evolution of lymphoproliferative disorders. We investigated four functional promotor polymorphisms in the TNF-alpha gene for association with the development of primary gastric B-cell lymphoma. PATIENTS AND METHODS: A total of 144 lymphoma patients, 595 H. pylori-infected controls and 534 healthy blood donors were genotyped for TNF-alpha-238, -308, -857, and -1031 by Taqman technology and case-control analysis was conducted. RESULTS: There was no significant difference in allele and genotype frequencies in H. pylori-infected patients and healthy controls. TNF-857 T allele was found in 15.1% of patients with low-grade lymphoma and 9.1% of H. pylori-infected patients (Pearson's=5.7, p=0.017, OR=1.8, Wald 95% CI: 1.1< O.R.< 2.8). Carrier of the rare allele T had a 1.8-fold increased risk to develop low-grade lymphoma (Pearson's=5.4, p=0.021). Patients with high-grade lymphoma were significantly more frequent carriers of the TNF-857 T allele than healthy blood donors (30.9%vs 18.9%, Pearson's=4.5, p=0.033). Carriage of the T allele conferred a 1.9-fold increased risk (Wald 95% CI: 1.0相似文献   

Point mutations in the tyrosine aminotransferase gene in tyrosinemia type II.

Tyrosinemia type II (Richner-Hanhart syndrome, RHS) is a disease of autosomal recessive inheritance characterized by keratitis, palmoplantar hyperkeratosis, mental retardation, and elevated blood tyrosine levels. The disease results from deficiency in hepatic tyrosine aminotransferase (TAT; L-tyrosine:2-oxoglutarate aminotransferase, EC 2.6.1.5), a 454-amino acid protein encoded by a gene with 12 exons. To identify the causative mutations in five TAT alleles cloned from three RHS patients, chimeric genes constructed from normal and mutant TAT alleles were tested in directing TAT activity in a transient expression assay. DNA sequence analysis of the regions identified as nonfunctional revealed six different point mutations. Three RHS alleles have nonsense mutations at codons 57, 223, and 417, respectively. One "complex" RHS allele carries a GT----GG splice donor mutation in intron 8 together with a Gly----Val substitution at amino acid 362. A new splice acceptor site in intron 2 of the fifth RHS allele leads to a shift in reading frame.     

Expression of ATP7B in human gastric cardiac carcinomas in comparison with distal gastric carcinomas

~~Expression of ATP7B in human gastric cardiac carcinomas in comparison with distal gastric carcinomas~~1 Wang LD, Zheng S, Zheng ZY, Casson AG. Primary adenocarcinomas of lower esophagus, esophagogastric junction and gastric cardia: in special refere…     

Amount of H antigen expressed on circulating von Willebrand factor is modified by ABO blood group genotype and is a major determinant of plasma von Willebrand factor antigen levels

To investigate whether the effect of ABO blood group on plasma von Willebrand factor (vWF) levels is mediated by the ABH antigenic determinants carried on N-linked glycans of vWF, we studied 158 group A and group O healthy volunteers. vWF antigen (vWF:Ag) and factor VIII antigen (FVIII:Ag) levels were highest in A(1)A(1) individuals and higher in A(1)O(1) than in A(2)O(1) or O(1)O(1) individuals. Plasma A transferase activity and the amount of A antigen expressed per unit vWF (AvWF) were significantly higher in A(1)A(1) than in A(1)O(1) individuals and higher in A(1)O(1) than in A(2)O(1) individuals. AvWF was correlated strongly with plasma levels of A transferase activity. Thus, we have clearly demonstrated a direct relationship between ABO genotype, A transferase expression, and the amount of A antigen expressed on circulating vWF. H antigen expression per unit vWF (HvWF) was highest in group O individuals. Among group A individuals, the pattern of HvWF expression was A(2)O(1)>A(1)O(1)>A(1)A(1). In group O and group A(2)O(1) individuals, HvWF was inversely correlated with plasma vWF levels. In contrast, among group A(1)A(1) and A(1)O(1) individuals, there was no relationship between AvWF and plasma vWF levels. These findings suggest that it is H antigen expression that mediates the ABO effect on plasma vWF concentration.     

Immunohistochemical analysis of pro-apoptotic PUMA protein and mutational analysis of PUMA gene in gastric carcinomas

BACKGROUND: Mounting evidence indicates that alteration of apoptosis is involved in the mechanisms of cancer development. PUMA, a pro-apoptotic member of Bcl-2 family, mediates p53-dependent and -independent apoptosis. AIM: The aim of this study was to explore whether alteration of PUMA protein expression is a characteristic of human gastric carcinomas. PATIENTS AND METHODS: We analysed expression of PUMA protein in 60 gastric adenocarcinomas by immunohistochemistry. Also, we examined PUMA gene mutation in the same tissues by a single-strand conformation polymorphism. RESULTS: PUMA protein expression was detected in 44 cases (73%) of the 60 gastric carcinomas, whereas it was not detected in normal gastric mucosal epithelial cells. The mutational analysis revealed no PUMA mutation in the gastric carcinomas. CONCLUSIONS: Our data suggest that PUMA mutation is not a direct target of inactivation in gastric tumourigenesis. Also, increased expression of PUMA in malignant gastric epithelial cells compared with normal mucosal epithelial cells suggested that PUMA expression may play a role in gastric tumourigenesis.     

Identification of a novel A2 allele derived from the A transferase gene through a nucleotide substitution G539C

BACKGROUND AND OBJECTIVES: The A2 is a very rare phenotype in the ABO blood group system in the Oriental population. It corresponds to a special ABO allele encoding a glycosyltransferase that is capable of synthesizing A2 antigens, which is weaker than the typical A antigen. In this study, we report a novel A2 allele in two unrelated Taiwanese individuals. MATERIALS AND METHODS: Two individuals were identified as the A2 phenotype based on the standard ABO serological test. For analysing the A2 allele, both direct sequencing and gene cloning of the ABO gene were performed. RESULTS: The ABO gene of the two A2 individuals was composed of O1 and A2 alleles, and the novel A2 allele has a 539G > C that results in the amino acid change Arg180Pro. The mutation was not detected in the general group A population. CONCLUSION: We report for the first time that a 539G > C mutation represents a new molecular basis for the A2 blood type. The amino acid substitution from arginine to proline may have effect on the expression of A antigen.     

Kinetic studies on Korean serum cis-AB enzymes reveal diminished A and B transferase activities

BACKGROUND: cis-AB enzymes are rare glycosyltransferases that synthesize both blood group A and B antigens. We have identified a large cohort of Korean cis-AB blood donors and studied the N-acetylgalactosaminyltransferase (glycosyltransferase A, GTA) and galactosyltransferase (glycosyltransferase B, GTB) activity of their cis-AB serum enzymes. MATERIALS AND METHODS: The cis-AB01 allele was identified by PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) in 60 donors collected at the Gwangju-Chonnam Red Cross Blood Center. Enzyme assays of this cis-AB enzyme were performed on available serum samples from 16 donors with the cis-AB01/O genotype and three with the cis-AB01/A genotype. RESULTS: In cis-AB donors with an O allele, both the GTA and GTB activity of the cis-AB enzyme were markedly reduced compared to normal A and B controls (29% and 27%, respectively). This is consistent with the behaviour predicted from kinetic studies of a recombinant model of the corresponding AAAB enzyme. CONCLUSION: Although variable, cis-AB enzymes feature reduced GTA and GTB activities. SUMMARY: Cis-AB enzymes feature variable but reduced GTA and GTB activities with relatively weaker GTB activity, consistent with the weak agglutination present on forward typing with anti-B.     

Polymorphisms of the carcinogen detoxifying UDP-glucuronosyltransferase UGT1A7 in proximal digestive tract cancer

Cancer of the proximal digestive tract is associated with tobacco smoke and ethanol exposure. The UDP-glucuronosyltransferase (UGT) 1A7 is a detoxifying enzyme capable of tobacco-borne carcinogen detoxification and cellular protection and has been implicated as a cancer risk gene. In this study, UGT1A7 expression is demonstrated in oral, esophageal, and gastric tissue, which are the principle sites of proximal digestive tract cancer. Genomic DNA from the blood of 76 patients with esophageal, orolaryngeal and gastric cancer as well as from 210 healthy blood donors was analysed for the presence of UGT1A7 polymorphisms by sequencing and temperature gradient gel electrophoresis. Wild type UGT1A7 alleles were equally distributed between controls (19 %) and cancer patients (22 %). However, the UGT1A7*3 allele combining W208R, N129K and R131K missense mutations and exhibiting substantially reduced carcinogen detoxification activity was significantly associated with proximal gastrointestinal cancer and identified as a risk allele present in 32 % of cancer patients and 19 % of controls (P = 0.0008, OR 2,02 (95 %-CI 1.33-3.07)). We identify the significant association of the UGT1A7*3 allele encoding a low catalytic activity protein as a risk gene in proximal digestive tract cancer and as a potential marker for cancer susceptibility.     

Molecular basis of the A<Subscript>2</Subscript>B in Taiwan

Molecular genotyping of the ABO alleles has been widely used in ABO subgroups analysis and has been able to solve the rare ABO blood grouping discrepancies. The genotypes of sixty-one A(2)B phenotype donors recruited from the middle and south of Taiwan were analyzed by means of molecular methods. The A(2)B phenotype was initially identified by serological test. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to screen the ABO alleles at nucleotides (nt) 261 and 703 based on the nt differences found in the ABO alleles. The subgroups of the A(2) allele were determined by the PCR-RFLP and direct sequencing methods. The discrepancies between the phenotype and genotype of the A(2)B were then studied by subcloning and nucleotide sequence analysis. Our results show that 55 of the 61 A(2)B donors (90%) are A205/B allele and two are A201/B allele. Four cases were heterozygotes of the cis-AB/O or B alleles. Two were cis-AB04/O allele, one was cis-AB01/O allele and the other was cis-AB02/B allele. In conclusion, most A(2)B genotypes belong to the A205/B allele in Taiwan. In this study, we report for the first time the presence of the A205, A201, and cis-AB02 alleles in Taiwan.     

Differential gene and protein expression in primary gastric carcinomas and their lymph node metastases as revealed by combined cDNA microarray and tissue microarray analysis

OBJECTIVE: To gain insight into the molecular events of lymph node metastasis of human gastric carcinoma. METHODS: The gene expression profile of five matched primary gastric carcinomas and their lymph node metastases was analyzed by complementary DNA (cDNA) microarray. Differential genes were identified in the metastatic and corresponding primary tumor pairs. Among the differentially expressed genes, carbonic anhydrase II (CAII) and insulin-like growth factor binding protein 4 (IGFBP 4) genes were detected by RT-PCR. CTTN protein expression was examined by tissue microarray. RESULTS: There was a high expression (over twofold) of 44 genes and a low expression (under twofold) of 32 genes in lymph node metastasis compared with primary gastric carcinoma, respectively. CAII mRNA was downregulated and IGFBP 4 mRNA was upregulated in paired lymph node metastases of gastric carcinomas. The overexpression of CTTN protein was related to the lymph node metastasis and the clinical stage of gastric carcinomas. CONCLUSION: This study showed that there is a low expression of genes relative to growth signal and immune response in lymph node metastases, and a high expression of genes relative to growth factor, cell cycle, cell motility and adhesion in lymph node metastases compared with primary gastric carcinomas. The expression of CTTN was related to the invasion and metastasis of gastric cancer.     

Association of ezrin expression in intestinal and diffuse gastric carcinoma with clinicopathological parameters and tumor type

AIM： To investigate the correlation between ezrin expression and types of gastric carcinoma and clinicopathological variables.
METHODS： We examined ezrin protein expression in 75 gastric carcinoma （53 intestinal types of adenocarcinoma, 22 diffuse types of carcinoma） tissues by immunohistochemistry. The results were compared with clinicopathological parameters such as tumor type, grade of tumor, clinical stage, presence of metastatic lymph node, and depth of invasion.
RESULTS： Ezrin immunostaining was positive in 43 cases （81.1%） of intestinal type and in 9 （40.9%） cases of diffuse type adenocarcinomas （P 〈 0.001）. In gastric carcinomas, the expression of ezrin protein correlated with the status of H py/ori and survival. There was no correlation between expression of ezrin with TNM stage and histological grade of gastric carcinomas （P 〉 0.05）.
CONCLUSION： The low expression of ezrin implicates the loss of adhesion in diffuse carcinomas. Furthermore, overexpression of ezrin in carcinomas with H pylori infection may be a genuine specific pathway in which Hpylori may cause/initiate gastric carcinoma.     

Molecular cloning and characterization of DNA sequences encoding rat and human atrial natriuretic factors.

A cDNA copy of the message encoding rat atrial natriuretic factor (ANF) has been cloned in Escherichia coli, and its nucleotide sequence was determined. ANF appears to be synthesized as a larger precursor, atrial pronatriodilatin. The cDNA has an open reading frame potentially encoding a protein of 152 amino acids, of which the first 24 amino acids strongly resemble a signal sequence. This is followed by a sequence with 80% homology to a second vasoactive protein, porcine cardiodilatin. The ANF peptide is contained in the COOH-terminal portion of the protein. The DNA sequence corresponding to human ANF is also presented and displays a high degree of homology to its rat counterpart. These data provide further evidence for the expression in cardiac atria of a multifactor system that may contribute to the regulation of blood pressure and extracellular fluid volume.     

Evaluation of Histo-Blood Group ABO Genotyping in a Danish Population: Frequency of a Novel O Allele Defined as O2

Traditional blood group ABO serology is based on immunoreactivity with the carbohydrate determinants A, B and H antigens. Recent advances at the DNA level of the ABO genes have provided a molecular genetic model for the ABO polymorphism. This genetic model has to date only been tested on a limited basis. The present study was initiated to evaluate the universality of the proposed genetic model on a larger group of serologically defined ABO phenotypes. Three hundred healthy Danish blood donors were analysed (A: 50, B: 50, AB: 50, O: 150) by PCR amplification followed by diagnostic restriction enzyme cutting. In all cases A, B, and AB at least one allele of correctly predicted status was found. However, in O phenotype individuals, 11 out of 150 carried one allele discordant to the proposed genetic model. This novel O allele (3.7% allele frequency) was further characterized by diagnostic restriction enzyme analysis in two positions divergent between A and B alleles and by DNA sequencing of the two major exons. The novel O allele is termed O² as it typed as B in nucleotide position 526 and as A in positions 703, 796, and 803, in contrast to the most predominant O allele termed O¹, which types as A in all 4 positions. The structural defect in the O² allele appears to be an additional substitution at nucleotide position 802. The results clearly demonstrate that with the addition of the two distinctly different O alleles, O¹, O², the previously proposed molecular genetic basis of the ABO polymorphism is quite valid. More importantly the determined characteristics of these two O alleles have practical implications in ABO genotyping, because it establishes within the limits of the number of samples tested that ABO genotypes can be assessed directly by non-allele specific PCR amplification and restriction enzyme analysis.     

Expression of transforming region of Moloney murine sarcoma virus in Escherichia coli as a fusion protein with small tumor antigen of polyoma virus.

Bacterial expression of the transforming region of Moloney murine sarcoma virus, designated mos, was obtained as a fusion protein with a portion of the small tumor antigen of polyoma virus. This was accomplished by fusing the entire mos open reading frame, encoding a 41,000-dalton protein, with a plasmid that expresses a beta-galactosidase-polyoma fusion protein under lac operon control. The resulting plasmid directed synthesis of the predicted polyoma antigen-sarcoma virus fusion protein of 59,000 daltons. This protein was immunoprecipitated by an anti-polyoma tumor antigen antiserum that recognized polyoma determinants at the NH2 terminus of the hybrid protein. This protein was also immunoprecipitated by an antiserum directed against a synthetic peptide containing the 12 COOH-terminal amino acids encoded by the mos open reading frame. This work confirms the existence of a long open reading frame in the mos gene and resolves a discrepancy between different nucleotide sequences for its COOH-terminal coding region.