Ubjects to further evaluate the influence of the TNFA -308 G.A polymorphism on gastric cancer risk and progression in a Chinese population.Biosystems, Foster City, CA, USA), which uses two allele-specific TaqMan MGB probes and a PCR primer pair to detect the specific SNP target. The sequence of the primers and probes are available on request. The reaction mixture of 10 mL contained 20 ng genomic DNA, 3.5 mL of 26 TaqMan Genotyping Master Mix, 0.25 mL of the primers and probes mix and 6.25 mL of double distilled water. The amplification was performed under the following conditions: 50uC for 2 min, 95uC for 10 min followed by 45 cycles of 95uC for 15 sec, and 60uC for 1 min. Following the manufacturer’s instructions, amplifications were conducted in the 384-well ABI 7900HT Real Time PCR System (Applied Biosystems, Foster 11967625 City, CA, USA) and the allelic discrimination were performed using the SDS 2.4 software (Applied Biosystems, Foster City, CA, USA). The genotyping rates of these SNPs were all above 98 . To ensure the accuracy of genotyping, two negative experimental control (water) and two positive experimental controls with known genotype were included in each reaction plate. In Title Loaded From File addition, about 5 of the samples were randomly selected for repeated genotyping for confirmation; and the results were 100 concordant.Materials and Methods Ethics statementThe study was approved by the Institutional Review Board of the Nanjing Medical University, Nanjing, China. At recruitment, written informed consent was obtained from all participants involved in this study.Statistical analysisBefore further analysis, the allele frequencies of TNFA 308G.A polymorphism in the controls of test set, validation set and combined set were assessed against departure from HardyWeinberg equilibrium (HWE) using a goodness-of-fit x2-test. Differences in the distributions of age, sex and frequencies of genotypes of the TNFA -308G.A polymorphism between the cases and controls were evaluated by Pearson’s x2 test. The associations between the -308G.A genotypes and risk of gastric cancer as well as the clinical characteristics of the patients were measured by computing odds ratios (ORs) and 95 confidence intervals (CIs) from unconditional logistic regression analysis with the adjustment for age and sex. All the statistical analyses were performed with the software SAS 9.1.3 (SAS Institute, Cary, NC, USA) and a two-side P value of less than 0.05 was considered as statistically significant.Study populationThis is an ongoing molecular epidemiologic study of gastric cancer conducted in the First Affiliated Hospital of Nanjing Medical University, Nanjing, China. The design of the study and the inclusion criteria of the subjects were previously described elsewhere [22]. In brief, two independent hospital-based casecontrol studies were included in the present study. Overall, the test set included 750 gastric cases and 835 age and sex-matched controls recruited at the second affiliated hospital of Nanjing Medical University, Nanjing and Cancer Hospital of Nantong City, Nantong, China from March, 2006 to January, 2010, and the validation set included 936 cases and 1,060 controls enrolled from Yixing People’s Hospital, Yixing, China from January, 1999 to December, 2006. All subjects were ethnic Han Chinese coming from different families and had no blood relationship. All the patients were newly diagnosed with Title Loaded From File histopathologically confirmed, incident gastric cancer and were consecutiv.Ubjects to further evaluate the influence of the TNFA -308 G.A polymorphism on gastric cancer risk and progression in a Chinese population.Biosystems, Foster City, CA, USA), which uses two allele-specific TaqMan MGB probes and a PCR primer pair to detect the specific SNP target. The sequence of the primers and probes are available on request. The reaction mixture of 10 mL contained 20 ng genomic DNA, 3.5 mL of 26 TaqMan Genotyping Master Mix, 0.25 mL of the primers and probes mix and 6.25 mL of double distilled water. The amplification was performed under the following conditions: 50uC for 2 min, 95uC for 10 min followed by 45 cycles of 95uC for 15 sec, and 60uC for 1 min. Following the manufacturer’s instructions, amplifications were conducted in the 384-well ABI 7900HT Real Time PCR System (Applied Biosystems, Foster 11967625 City, CA, USA) and the allelic discrimination were performed using the SDS 2.4 software (Applied Biosystems, Foster City, CA, USA). The genotyping rates of these SNPs were all above 98 . To ensure the accuracy of genotyping, two negative experimental control (water) and two positive experimental controls with known genotype were included in each reaction plate. In addition, about 5 of the samples were randomly selected for repeated genotyping for confirmation; and the results were 100 concordant.Materials and Methods Ethics statementThe study was approved by the Institutional Review Board of the Nanjing Medical University, Nanjing, China. At recruitment, written informed consent was obtained from all participants involved in this study.Statistical analysisBefore further analysis, the allele frequencies of TNFA 308G.A polymorphism in the controls of test set, validation set and combined set were assessed against departure from HardyWeinberg equilibrium (HWE) using a goodness-of-fit x2-test. Differences in the distributions of age, sex and frequencies of genotypes of the TNFA -308G.A polymorphism between the cases and controls were evaluated by Pearson’s x2 test. The associations between the -308G.A genotypes and risk of gastric cancer as well as the clinical characteristics of the patients were measured by computing odds ratios (ORs) and 95 confidence intervals (CIs) from unconditional logistic regression analysis with the adjustment for age and sex. All the statistical analyses were performed with the software SAS 9.1.3 (SAS Institute, Cary, NC, USA) and a two-side P value of less than 0.05 was considered as statistically significant.Study populationThis is an ongoing molecular epidemiologic study of gastric cancer conducted in the First Affiliated Hospital of Nanjing Medical University, Nanjing, China. The design of the study and the inclusion criteria of the subjects were previously described elsewhere [22]. In brief, two independent hospital-based casecontrol studies were included in the present study. Overall, the test set included 750 gastric cases and 835 age and sex-matched controls recruited at the second affiliated hospital of Nanjing Medical University, Nanjing and Cancer Hospital of Nantong City, Nantong, China from March, 2006 to January, 2010, and the validation set included 936 cases and 1,060 controls enrolled from Yixing People’s Hospital, Yixing, China from January, 1999 to December, 2006. All subjects were ethnic Han Chinese coming from different families and had no blood relationship. All the patients were newly diagnosed with histopathologically confirmed, incident gastric cancer and were consecutiv.