Introduction & Objective: Genetic agents play important roles in developing of cancers. Mutations and polymorphism affects on p53 protein function in suppressing tumor. We aimed to investigate the intron 3 polymorphism of p53 in Isfahanian breast invasive ductal carcinoma.

Materials & Methods: We undertook a case–control study on 192 controls and 192 patients with breast invasive ductal carcinoma from Isfahan. p53 intron 3 genotypes were identified using allele-specific PCR. The c2-test was used to assess the statistical significance of the data.

Results: In control samples, the genotype distribution for p53 intron 3 polymorphisms was 57.3% and 42.7% for the A1/A2 and A1/A1 genotypes, respectively. In the cancer group, 85.4% of the cases were A1/A2 and 14.6% were A1/A1. The differences in the distribution of the p53 intron 3 polymorphism between the cases and controls were statistically significant (P<0.001).

Conclusion: Our findings indicated that p53 intron 3 polymorphism probably is a genetic predisposing factor for breast invasive ductal carcinoma development in Isfahanian specimens.