RESUMO
Background: The association of a functional single nucleotide polymorphism at codon 72 of the p53 gene (Arg72Pro) with malignancy is a subject of controversy. We analyzed this polymorphism in 224 patients with gastrointestinal cancers (92 with stomach cancer and 132 with colorectal cancer) and in 163 healthy controls. Material and Methods: DNA was extracted from peripheral blood mononuclear cells and amplified with an allele-specific polymerase chain reaction. Results: There was no significant association between p53 alleles and gastrointestinal cancers. The frequency of the Arg allele was 59.7, 58.8, and 59.2% in the stomach cancer patients, colorectal cancer patients, and controls, respectively. Frequencies of the Pro allele were 40.3% in patients with stomach cancer, 41.2% in patients with colorectal cancer, and 40.8% in controls. Likewise, genotype frequencies did not differ significantly between the two patient groups and controls. There were no differences in genotype or allele frequencies by gender, age, or histological grade. Conclusions: The data do not support the association of the p53 codon 72 polymorphism with stomach or colorectal cancers in Iranian patients.