Lack of Effects of Single Nucleotide Polymorphisms of the DNA Methyltransferase 1 Gene on Gastric Cancer in Iranian Patients: A Case Control Study


Background: Gastric cancer is one of the most common malignant tumors in Iran. Hypomethylation and/orhypermethylation of DNA has been described in gastric cancer and is presumed to be an early event incarcinogeneisis.
Objective: We therefore hypothesized that single nucleotide polymorphisms of the DNMT1gene may be associated with the genetic susceptibility to gastric cancer.
Methods: Totals of 200 patients and 200controls, both of Iranian origin, were studied. Three polymorphisms were genotyped by PCR-RFLP and allelefrequencies and genotypes were compared between the cases and controls. Odds ratios were calculated and theinteractions between the polymorphisms, age and sex were examined. Results : There were no significantassociations between the DNMT1 polymorphisms and gastric cancer.
Conclusion: We could not show anyassociation between DNMT1 polymorphisms and gastric cancer. Larger sets of polymorphisms and samplesizes are required for future testing of possible associations.