Association between Vitamin D Receptor Gene BsmI Polymorphism and Bone Mineral Density in A Population of 146 Iranian Women

OBJECTIVE Osteoporosis is a bone disorder that reduces bone mineral density (BMD) and leads to bone fracture. In addition to different factors, gene polymorphisms have been revealed to be associated with osteoporosis. In this study, we investigated the association between the BsmI polymorphism of vitamin D receptor (VDR) gene (rs1544410) and BMD in a population of Iranian women. MATERIALS AND METHODS In this case control study, clinical risk factors for osteoporosis were obtained from the participants through a questionnaire for a case-control study. The World Health Organisation (WHO) criteria were applied for the diagnosis of the disease. Peripheral blood samples were obtained from 146 pre- and or postmenopausal Iranian women aged between 35 and 71 years (53.53 ± 9.8). The study population was classified for BMD into normal and osteoporotic groups, who matched for age, pregnancy status, menstrual condition, and body mass index (BMI). The BMD of the lumbar spine (L1-4) and femoral neck was measured. Polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) was performed to detect and analyze the genotype. RESULTS The frequencies of AA and GG were significantly different between the two groups (p value<0.05), with the first genotype being higher in the patients and the second being higher in the normal group. The GG genotype was significantly associated with increased BMD in the lumbar spine (p value<0.05) but non-significant in the femoral neck (p value>0.05). CONCLUSION BsmI polymorphism of VDR gene has a significant association with BMD in the lumbar spine and may have a minor effect on the proximal femur BMD in Iranian women.