RESUMO
BACKGROUND: DNA methyltransferase-3B (DNMT3B) is an important enzyme responsible for maintaining the DNA methylation pattern in eukaryotic cells. In this study we have investigated the correlation between the 46359CâT polymorphism in the DNMT3B gene and the risk of breast cancer incidence among sporadic breast cancer patients in Fars Province, Southern Iran. METHODS: In this case-control study, 100 breast cancer patients and 138 healthy control subjects were genotyped for the DNMT3B gene by the polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: The genotype frequency in the case (CC 27%, CT 47%, TT 26%) group significantly (P=0.008) differed from the control (CC 19.56%, CT 67.3%, TT 13%) group. We observed a decreased association between the CT genotype and lymph node involvement in breast cancer patients. Our results have shown that in comparison to the homozygous CC genotype carriers the DNMT3B-CT genotype has a significantly lower risk for breast cancer (OR=0.515, 95% CI=0.267-0.994, P=0.048). CONCLUSION: Our case-control study showed that the CT genotype was significantly associated with decreased breast cancer risk. Consistent with these results, a significant decrease of CT genotype among lymph node positive breast cancer patients was observed. However, a larger study population with more clinical data is needed to confirm these results.
