Article Type

Original Study


Objective The aim of this study was to assess the association of vitamin D receptor (VDR) gene polymorphism BsmI in cases of primary immune thrombocytopenic purpura (ITP). Background Recently, several studies have demonstrated the role of VDR polymorphisms in the development of autoimmune diseases. Vitamin D affects both innate and adaptive immune responses, which have been held responsible in ITP pathogenesis. Patient and methods VDR polymorphism BsmI (rs1544410) was detected by PCR followed by restriction fragment length polymorphism analysis. DNA samples were extracted from the peripheral blood of 40 ITP patients and 60 geographically and ethnically matched healthy controls. Results A statistically significant difference was found in the BsmI polymorphism between ITP patients and controls (χ2 = 8.77, P = 0.01). The BsmI polymorphism B allele was higher in ITP patients compared with controls but with a statistically insignificant difference (χ2 = 2.125, P = 0.145). The bb genotype played a protective role in ITP incidence. Conclusion This is the first published report on VDR gene polymorphisms in adult ITP patients. The BsmI genotype was associated with increased risk for ITP incidence with no obvious effect on bleeding severity, platelet count, or site of bleeding.