TGFβ C-509T, TGFβ T869C, XRCC1 Arg194Trp, IKBα C642T, IL4 C-590T Genetic polymorphisms combined with socio-economic, lifestyle, diet factors and gastric cancer risk: A case control study in South Indian population

Background: Gastric cancer is worldwide the third major cause of cancer related death. Risk factors for gastric cancer includes Helicobacter pylori infection, gastric ulcer, less hygienic condition, use of tobacco, alcohol consumption, use of salted, smoked food, genetic alterations etc. In order to identify the risk factors associated with gastric cancer in South Indian population a case-control study involving 200 proven gastric cancer cases and 400 controls was conducted. Methods: A structured questionnaire was used to interview all the subjects who participated in our study. Genotyping assay was performed using Taqman allelic discrimination assay for 5 Single Nucleotide Polymorphisms (SNPs)-TGF beta C-509T, TGF beta T869C, XRCC1 Arg194Trp, IkB alpha C642T and IL4C-590T. Results: Odds Ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression. Statistical analysis on socio-economic factors, lifestyle factors had showed that subjects from low socio economic status, use of tobacco and consumption of non-vegetarian food had increased risk of developing gastric cancer. Multi-factorial analysis for the SNPs adjusting for the risk factors obtained in this study showed that TGFB C-509T TT genotypes had four fold increased risk of gastric cancer (OR= 4.11, CI= 1.02-16.56) and TGF beta T869C CC genotype had a decreased risk of gastric cancer (OR= 0.21, CI= 0.05-0.85). Conclusion: Economic status, tobacco use and food habits play a significant role in gastric cancer development. TT genotype for TGF beta C-509T had an increased risk and CC genotype for TGF beta T869C had a decreased risk of gastric cancer in south Indian population after adjusting for socio-economic factors and lifestyle factors.