DNMT1 rs2228611, rs2228612 and DNMT3A rs2276598, rs752208 Polymorphisms and Their Association with Breast Cancer Phenotype and Prognosis

<i>Background and Objectives</i>: Breast cancer is a leading cause of cancer-related deaths globally. This study investigates the impact of genetic polymorphisms in DNA methyltransferases (<i>DNMT1</i> and <i>DNMT3A</i>) on breast cancer pathomorphology and patient prognosis. Specifically, we focused on <i>DNMT1</i> polymorphisms rs2228611 and rs2228612 and <i>DNMT3A</i> polymorphisms rs2276598 and rs752208. <i>Materials and Methods</i>: Conducted at the Institute of Oncology of the Lithuanian University of Health Sciences, this study included 201 Lithuanian women with early-stage breast cancer. DNA was extracted from peripheral blood samples, and genotyping for the specified polymorphisms was performed using the PCR-RFLP assay. Statistical analyses were applied to evaluate associations between polymorphisms and clinicopathological characteristics. <i>Results</i>: The non-carriers of the <i>DNMT1</i> rs2228611 G allele were less likely to be diagnosed at an older age, while the <i>DNMT3A</i> rs752208 T allele was linked to lower-grade tumors. Survival analysis indicated a potential relationship between <i>DNMT3A</i> rs752208 and overall survival, although no significant findings were observed in progression-free or metastasis-free survival. <i>Conclusions</i>: This study suggests that the <i>DNMT1</i> and <i>DNMT3A</i> polymorphisms may influence breast cancer pathomorphology and prognosis. The <i>DNMT1</i> rs2228611 G allele may be associated with earlier onset, and the <i>DNMT3A</i> rs752208 T allele might correlate with less aggressive tumors. These findings underscore the potential of <i>DNMT</i> gene polymorphisms as prognostic biomarkers in breast cancer, warranting further investigation with larger sample sizes.