RESUMO
BACKGROUND/AIMS: Gastric cancer, as the fourth most frequent malignancy worldwide, has the highest rate among cancer-related disorders in Ardabil province, located in North-West Iran. Methylene tetrahydrofolate reductase is one of the cancer susceptibility genes with considerable polymorphisms. Methylene tetrahydrofolate reductase C677T leads to a decrease of about 30% in its product activity and is reported to have an effect on cancer susceptibility. MATERIALS AND METHODS: Methylene tetrahydrofolate reductase C677T genotyping was carried out by polymerase chain reaction-restriction fragment length polymorphism on peripheral blood DNA from 76 gastric cancer patients and 91 healthy controls. The statistical significance was calculated by logistic regression analysis. RESULTS: The mean age was 64.2±11.1 and 62.1±9.8 years for cases and controls, respectively. Among tumors, 35.5% were diffuse type and others were intestinal. The frequency of genotypes was 61.8%, 32.9%, and 5.3% among cases and 45.1%, 50.6%, and 4.4% among controls for Ala/Ala, Ala/Val, and Val/Val, respectively. CT heterozygotes had lower susceptibility to gastric cancer (p=0.02). This relationship of significance was detected considering gender and age. CONCLUSIONS: It was found that T allele has a protective association with age in the Ardabil province.