Association of ApaI and Taq1 polymorphic site of vitamin D receptor gene with bone mineral density in women aged 45 years and older

Osteoporosis is a silent disease causing decrease in firmness and accumulation of bone, and leading to increase in bone fracture. The importance of ApaI and TaqI polymorphisms of vitamin D receptor gene in bone metabolism and density has been shown in other parts of world. The aim of the present research was to study the association of these polymorphisms with bone mineral density in women with 45 years old and older in Chahamahal and Bakhteiari province. In this descriptive analytical study, 200 women participated aged 45 years old and older who referred to Bone Mineral Density Assay Centers in Shahrekord in years 2012-2013. Bone mineral density at femur neck and lumbar spine was measured by DEXA method. Based on T- score, these women divided tin two groups, 130 patient individuals and 70 healthy individuals. Then, different genotypes of Taq1 (TT/Tt/tt) and ApaI (AA/Aa/aa) were determined by PCR-RFLP method and their frequencies were calculated. Statistical analyses did not show any significant relationship between ApaI polymorphism and bone density (P>0.05). TaqI polymorphism and femur neck bone density showed a significant relationship (P<0.05), but no significant relationship was seen with lumbar spine bone density (P>0.05). Patients with hemozygote dominant genotype (TT) compared with other genotypes had the least femur neck bone mineral density. Lumbar spine bone mineral density in all genotypes of TaqI was identical. TaqI polymorphism may be a good marker for diagnosis of osteoporosis in susceptible women in Chahamahal and Bakhteiari Province and even in Iran. However, further and larger populations should be studied to verify the results of this study.