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Abstract: The aim of this study was to assess whether p53 codon 72 polymorphism is associated with an increased risk of lung cancer (LC) in a South Korean population. We conducted a population-based, large-scale, case-control study including 3939 patients with LC and 1700 controls. P53 codon 72 polymorphism was determined by real-time polymerase chain reaction (PCR). The frequencies of p53 codon 72 polymorphisms (Arg/Arg, Arg/Pro, and Pro/Pro) in LC were 37.0%, 46.2%, and 16.7%, respectively; frequencies in the controls were 43.2%, 45.6%, and 11.2%, respectively (p <0.01). The Arg/Pro and Pro/Pro genotype were significantly associated with increased risk of LC (odds ratio (OR)=1.22, 95% confidence interval (CI)=1.06–1.14 and OR=1.83, 95% CI=1.48–2.26, respectively) compared with the Arg/Arg genotype. Risk was compared in different subgroups. The OR of Pro/Pro genotype was significantly higher in small cell lung cancer (SCC) and squamous cell carcinoma (SQC) than in adenocarcinoma (ADC). Higher OR of Pro/Pro genotype was also seen among males. However, relationships between gender, age, smoking, and genotypes were not found. P53 codon 72 polymorphism was associated with an increased risk of LC in this Korean population; the association was especially noteworthy in SQC, SCC, and males. [Copyright &y& Elsevier]

Recently pseudorabies outbreaks have occurred in many vaccinated farms in China. To identify genetic characteristics of pseudorabies virus (PRV) strains, we obtained the genomic sequences of PRV strains HeN1 and JS, which were compared to 4 PRV genomes and 729 partial gene sequences. PRV strains isolated in China showed marked sequence divergence compared to European and American strains. Phylogenetic analysis revealed that for the first time PRV can be divided into 2 distinct clusters, with Chinese strains being genotype II and PRVs isolated from other countries being genotype I. Restriction fragment length polymorphism analysis confirmed differences between HeN1 and Bartha strains, as did the presence of unique insertion/deletion polymorphisms and microsatellites. This divergence between the two genotypes may have been generated from long-term, independent evolution, which could also explain the low efficacy of the Bartha vaccine in protecting pigs infected with genotype II PRV. [ABSTRACT FROM AUTHOR]

Low levels of folate combined with high levels of homocysteine may cause unexplained recurrent pregnancy loss (URPL). However, the relationships between polymorphisms in genes of the folate metabolic pathway and URPL remain controversial. We conducted a case-control study to explore polymorphisms of the major folate pathway genes, including methylenetetrahydrofolate reductase (MTHFR) 677C>T, MTHFR 1298A>C, methionine synthase (MTR) 2756A>G, methionine synthase reductase (MTRR) 66A>G and reduced folate carrier 1 (RFC-1) 80A>G, and their associations with URPL. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine the distributions of MTHFR, MTR and RFC-1 polymorphisms, and the results were validated using direct sequencing. The polymorphisms in MTRR were determined using direct sequencing. Haplotypes were analyzed using SHEsis, an online tool for biological analysis. We found that the MTHFR 677T allele and the 677T/1298A/2756A/66A/80G haplotype were risk factors for URPL, while the MTR 2756G allele and the 677C/1298A/2756A/66A/80A haplotype exhibited protective effects on susceptibility to URPL in a Chinese Han population from the Hangzhou area. [ABSTRACT FROM AUTHOR]

Background: Although previous studies have demonstrated an association between ABO blood group and the risk of gastric cancer (GC), only one study has identified these associations using the ABO genotype; however, that study did not evaluate sex differences in this association. The aim of the present study was to investigate whether there are sex-specific differences in the ABO genotype-associated risk of GC. In addition, we explored the association of the ABO genotype and the clinicopathologic characteristics of GC in a Korean population. Methods: We conducted a large-scale case-control study of 3245 GC patients (2204 males, 1041 females) and 1700 controls (821 males, 879 females). The ABO genotype was determined by multicolor real-time polymerase chain reaction (PCR) using displacing probes. Results: As compared with genotype OO, genotypes AA and AO in females, but not in males, were associated with a significantly increased risk of GC (odds ratio [OR] 1.56 and 95 % confidence interval [CI] 1.08-2.26 for AA; OR 1.57 and 95 % CI 1.21-2.03 for AO). In a subgroup analysis, blood group A had a significantly increased risk of diffuse-type GC (OR 2.00, 95 % CI 1.43-2.78), but not of intestinal-type (OR 1.31, 95 % CI 0.96-1.79) or mixed-type GC (OR 1.43, 95 % CI 0.92-2.24). Conclusion: The ABO genotypes AA and AO were significantly associated with GC only in females and only for diffuse-type GC. These data suggest that the association between ABO blood group and GC risk may differ according to sex and histological type. [ABSTRACT FROM AUTHOR]

Background: The interaction between Src homology 2 domain-containing protein tyrosine phosphatase (SHP-2) of gastric epithelial cells and cagA from H. pylori plays a crucial role in developments of gastric atrophy and gastric cancer. This study aimed to investigate the association of haplotype tagging SNPs (htSNPs) in the PTPN11 gene encoding SHP-2 with gastric atrophy and gastric cancer in Chinese population. Methods: The subjects comprised 414 patients with gastric cancer, 109 individuals with gastric atrophy and 923 healthy controls. Blood was collected from October 2008 to October 2010. Five htSNPs rs2301756, rs12423190, rs12229892, rs7958372 and rs4767860 from the PTPN11 gene were selected and genotyped by Taqman assay. Serum Ig G antibodies to H. pylori were detected by ELISA. Gastric atrophy was screened by the levels of serum pepsinogenIandII, and confirmed by endoscopy and histopatholgical examinations. Odds ratio (ORs) and 95% confidence intervals (CIs) were calculated by a multivariate logistic regression. Results: Among H. pylori seropositive subjects, age and gender-adjusted OR of gastric atrophy was 2.47 (95%CI 1.13-4.55, P = 0.02) for CC genotype compared with CT/TT genotypes, suggesting a recessive model of genetic risk for rs12423190. The prevalence of H. pylori seropositivity were significantly higher in groups of gastric cancer and gastric atrophy compared to the control group (70.3% vs. 75.2% vs. 49.7%, P <0.001). However, the distributions of genotypes and haplotypes in patients with gastric cancer were not significantly different from healthy controls. Conclusions: Our study provides the first evidence that rs12423190 polymorphism of the PTPN11 gene is significantly associated with an increased risk of gastric atrophy in H. pylori infected Chinese Han population, suggesting that rs12423190 polymorphism could be used as a useful marker of genetic susceptibility to gastric atrophy among H. pylori infected subjects. The biological roles of this polymorphism require a further investigation. [ABSTRACT FROM AUTHOR]

Background: The common p53 codon 72 polymorphism has been investigated as a risk factor for cancer in different populations; however, the results have been inconsistent. This study investigated the risk of developing gastric or colorectal cancer associated with the p53 codon 72 polymorphism in a Korean population. Methods: We conducted a large-scale case-control study that included 2,213 gastric cancer patients; 1,829 colorectal cancer patients; and 1,700 healthy controls. Genotyping was performed with real-time polymerase chain reaction (PCR), using a TaqMan single-nucleotide polymorphism (SNP) genotyping assay. Results: The frequencies of Arg/Arg, Arg/Pro, and Pro/Pro genotypes of the p53 codon 72 polymorphism were 43.3, 42.0, and 13.0% in the gastric cancer patients; 40.5, 45.0, and 14.0% in the colorectal cancer patients; and 43.2, 45.6, and 11.2% in the controls, respectively. The Pro/Pro genotype was associated with an increased risk of gastric [age- and sex-adjusted odds ratio (OR) = 1.25, 95% confidence interval (CI) = 1.01-1.56, P = 0.04] and colorectal cancer (OR = 1.36, 95% CI = 1.07-1.72, P = 0.01). There were no significant interactions between the p53 codon 72 polymorphism and smoking or drinking. Conclusions: Our results suggest that the Pro/Pro genotype is associated with modest increases in the risks of gastric cancer and colorectal cancer in a Korean population. [ABSTRACT FROM AUTHOR]

The inhibin β ( INHBB) gene was studied as a candidate gene for the prolificacy of Small Tail Han and Hu sheep. According to the sequence of exon 1 and 2 of bovine INHBB gene, six pairs of primers were designed to detect single nucleotide polymorphisms of exon 1 and 2 of INHBB gene in both high (Small Tail Han and Hu sheep) and low prolificacy breeds (Dorset, Texel and German Mutton Merino sheep) by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). Three pairs of primers (primers 1-1, 1-2 and 1-3) were used to amplify the exon 1, and others (primers 2-1, 2-2 and 2-3) to the exon 2. Only the products amplified by primer 2-3 displayed polymorphism. For primer 2-3, three genotypes (AA, AB and BB) were detected in Hu sheep and only AA genotype in other breeds. In Hu sheep, frequency of AA, AB and BB genotypes was 0.636, 0.046 and 0.318, respectively. Sequencing revealed 276A > G mutation (based on the amplification region of primer 2-3) which did not cause any amino acid change because it lay in the 3′ untranslated region. The ewes with genotype BB had 0.58 ( P < 0.01) lambs more than those with AA in Hu sheep. [ABSTRACT FROM AUTHOR]

Background: This study was designed to investigate an association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and the risk of lung cancer in a Korean population. Methods: We conducted a large-scale, case-control study involving 3938 patients with newly diagnosed lung cancer and 1700 healthy controls. Genotyping was performed with peripheral blood DNA for MTHFR C677T polymorphisms. Statistical significance was estimated by logistic regression analysis. Results: The MTHFR C677T frequencies of CC, CT, and TT genotypes were 34.5%, 48.5%, and 17% among lung cancer patients, and 31.8%, 50.7%, and 17.5% in the controls, respectively. The MTHFR 677CT and TT genotype showed a weak protection against lung cancer compared with the homozygous CC genotype, although the results did not reach statistical significance. The age- and gender-adjusted odds ratio (OR) of overall lung cancer was 0.90 (95% confidence interval (CI), 0.77-1.04) for MTHFR 677 CT and 0.88 (95% CI, 0.71-1.07) for MTHFR 677TT. However, after stratification analysis by histological type, the MTHFR 677CT genotype showed a significantly decreased risk for squamous cell carcinoma (age- and gender-adjusted OR, 0.78; 95% CI, 0.64-0.96). The combination of 677 TT homozygous with 677 CT heterozygous also appeared to have a protection effect on the risk of squamous cell carcinoma. We observed no significant interaction between the MTHFR C677T polymorphism and age and gender or smoking habit. Conclusions: This is the first reported study focusing on the association between MTHFR C677T polymorphisms and the risk of lung cancer in a Korean population. The T allele was found to provide a weak protective association with lung squamous cell carcinoma. [ABSTRACT FROM AUTHOR]

Background: This study was designed to investigate an association between the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and the risk of gastric and colorectal cancer in the Korean population. Methods: We conducted a population-based large-scale case-control study involving 2,213 patients with newly diagnosed gastric cancer, 1,829 patients with newly diagnosed colorectal cancer, and 1,700 healthy controls. Genotyping was performed with peripheral blood DNA for MTHFR C677T polymorphisms. The statistical significance was estimated by logistic regression analysis. Results: The MTHFR C677T frequencies of CC, CT, and TT genotypes were 35.2%, 47.5%, and 17.3% among stomach cancer, 34%, 50.5%, and 15.5% in colorectal cancer, and 31.8%, 50.7%, and 17.5% in the controls, respectively. The MTHFR 677TT genotype showed a weak opposite association with colorectal cancer compared to the homozygous CC genotype [adjusted age and sex odds ratio (OR) = 0.792, 95% confidence interval (CI) = 0.638-0.984, P = 0.035]. Subjects with the MTHFR 677CT showed a significantly reduced risk of gastric cancer compared whose with the 677CC genotype (age- and sex-adjusted OR = 0.810; 95% CI = 0.696-0.942, P = 0.006). We also observed no significant interactions between the MTHFR C677T polymorphism and smoking or drinking in the risk of gastric and colorectal cancer. Conclusions: The T allele was found to provide a weak protective association with gastric cancer and colorectal cancer. [ABSTRACT FROM AUTHOR]

Abstract: An oligonucleotide array technology was established for rapidly detecting and genotyping Chlamydia trachomatis in urogenital infections. The VS1–VS2 region of the omp1 gene was used to design oligonucleotide probes. Eleven serovar-specific probes to serovars A, B, C, D, E, F, G, H, I, J, and K, and 3 group-specific probes to group B (B, Ba, D, E, L1, and L2), group C (A, C, H, I, J, K, and L3), and an intermediate group (F and G) were synthesized and spotted onto the nylon membrane. Two pairs of universal primers were designed for the nested polymerase chain reaction (PCR) amplification of the VS1–VS2 gene. Digoxigenin-labeled amplicons of the VS1–VS2 gene of C. trachomatis were hybridized to the membrane array. Hybridization signals were read by the nitroblue tetrazolium/5-bromo-4-chloro-3-indolylphosphate color development. The assay developed was tested with reference strains of C. trachomatis serovars and clinical samples. The sensitivity was evaluated for 57 samples previously found to be positive for C. trachomatis by using plasmid PCR, and 98.2% (56/57) concordance was obtained. Fourteen oligonucleotide probes were optimized by trying different reaction conditions, showing specific hybridization with the corresponding reference strains, but no cross-reactions with other urogenital microorganisms. Using this procedure, a total of 59 strains were detected from 56 chlamydial samples. Eight genotypes were found, and type D, E, F, and H were the most frequently observed types (77.9%). Three cases (5.4%) had multiple infections with serovars: 1.D/E, 2.D/F, and 3.F/K. To validate the reference strains and confirm the genotype identity as determined by the oligonucleotide array technology, we sequenced all reference strains and 10 selected specimens across variable sequence VS1 and VS2. No discrepancies were found between the array typing and the genotype identity confirmed by nucleotide sequencing of the PCR product. The findings from this study indicated that the oligonucleotide array is a simple, fast, and specific assay for directly detecting and genotyping C. trachomatis from clinical samples. [Copyright &y& Elsevier]