Association between estrogen receptor a gene polymorphism and the risk of breast cancer in a group of Egyptian women

ABSTRACT

Estrogen receptor [ER] is a ligand-activated transcription factor that mediates estrogen actions in target tissues. Several common polymorphisms of the ER-alpha gene have been reported to be associated with alterations in receptor expression and function. We evaluated the hypothesis that genetic polymorphisms in the ER-alpha gene may be associated with breast cancer risk in Egyptians. In this study the involvement of two RFLPs at the ER-alpha gene locus, denoted as PvuII and XbaI in breast cancer were examined in 40 breast cancer cases and 33 age frequency-matched controls. A case-control comparison was performed and the genotype distributions examined according to different tumor and population parameters. PvuII polymorphism was associated with an increased risk of breast cancer [OR = 5.14, P=0.01], while there was no significant difference in genotype frequency of the XbaI polymorphism between controls and cases. The PvuII polymorphism was also associated with elevated breast cancer risk in premenopausal cases [OR=7.00, p=0.049]. In addition, significant association was found in patients with LN metastasis carrying the ER-alpha PvuII T allele [OR=7.14, p=0.013]. These results suggest that biomarkers for genetic polymorphisms could be used for the identification of breast cancer risk among Egyptian women