The influence of the genetic variant within miRNA-binding site in estrogen receptor alpha gene on the risk of breast cancer in postmenopausal women on hormone replacement therapy.

Objective: The aim of the study was to analyze the impact of the rs2747648 genetic variant in the estrogen receptor alpha (ER1) gene affecting a putative miR-453-binding site on the risk of breast cancer in postmenopausal women. Furthermore, we examined if the risk changes in a subset of women on hormone replacement therapy (HRT).

Patients And Methods: We studied 530 breast cancer cases and 270 controls of the same age and ethnicity. Duration of HRT use was ascertained through a postal questionnaire. Genotyping was accomplished by TaqMan® allelic discrimination assay. The associations with breast cancer risk were assessed using logistic regression models.

Results: The analysis did not reveal any association between the ER1 genetic variant and postmenopausal breast cancer risk, either ER-positive or ER-negative disease. Also, there was no association between the ER1 genetic variant and breast cancer risk in postmenopausal women receiving HRT.

Conclusion: There may be an inverse association between the premenopausal women carrying the variant allele and breast cancer, but it was not detected in our analysis for the postmenopausal women, or for those on HRT.