RESUMO
Background:The double strand break repair pathway, comprising XRCC2 and XRCC3 has crucial role in maintenance of genomic stability and prevention of tumor initiation and progression. Therefore, sequence variants of such DNA repair genes may compromise individual's DNA repair capacity and can influence risk of developing breast cancer. Method and Results:To estimate the impending effect of XRCC2 (Arg188His) and XRCC3 (Thr241Met) polymorphisms on breast cancer, 133 breast cancer patients and 154 healthy controls were evaluated by PCR-RFLP method. In the present study, it was noted that there was no significant correlation between these polymorphisms and breast cancer risk. However, within patient group, significant association of XRCC2 variants with PR negative breast cancer was detected. Further, patients with XRCC2 variant genotypes were also at high risk of developing TNBC and Her2 enriched subtypes as compared to luminal A subtype. Significant relation was also obtained between XRCC3 variants and large sized and infiltrative breast tumors. Conclusion: These noteworthy observations demonstrate potential involvement of XRCC2 and XRCC3 polymorphisms in pathophysiology of breast cancer.