Serum Vitamin D status and VDR (FokI) polymorphism association study in Pakistani females with breast cancer.

Abstract

Breast cancer is most common in Pakistani women at young age compared to West where it is most common after 60 years of age. Variations in genes controlling vitamin D activity would play a role in determining the risk of breast cancer in women at early age. To determine the association of vitamin D receptors (VDR) gene polymorphisms (FokI) with breast cancer risk in Pakistani women. FokI polymorphisms were studied through the polymerase chain reaction-restriction fragment length polymorphism technique on blood samples of 300 breast cancer and 300 healthy women. This study found that circulating level of 25(OH)D3 was significantly lower among breast cancer patients as well as healthy subjects. Patients with large tumor size had significantly lower vitamin D levels. VDR FokI genotypes were significantly distributed (P ≤ 0.00001) in Pakistani women with newly diagnosed breast cancer. A significant association between different FokI genotypes and circulating levels of 25(OH)D3 was found. Patients with FF genotype was significantly (P < 0.0001) associated with higher risk of breast cancer (OR 8.9, 95% CI 0.17-0.45) compared to Ff and ff genotype. VDR gene FokI polymorphism was associated with plasma vitamin D level and significant differences found in mean serum vitamin D levels between genotype groups of FokI. The study concluded that FokI might be one of the contributors to increase relative risk of breast cancer in Pakistani women.