Association between vitamin D receptor Apa1 and Taq1 genes polymorphism and osteoporosis in postmenopausal women

  Background: Osteoporosis is the commonest systemic disease leading to increased bone fragility and fracture. Vitamin D receptor Polymorphism is thought to have the most genetic influence on BMD.   Objective: The aim of this study was to investigate the association between vitamin D receptor Apa1 and Taq1 genes polymorphism and osteoporosis in postmenopausal women.   Methods: This was a case/control study in which 80 patients with osteoporosis (case group), referred to rheumatology ward at Boalisina Hospital during 2010 were investigated. The control group included an equal number of patients who visited other wards of the hospital for a variety of reasons. We obtained the bone mass densitometry (grams per centimeter square) results of case and control groups at the lumbar spine, wrist and hip by dual-energy X-ray absorptiometry. The distribution of Apa1 and Taq1 polymorphism in the VDR gene was determined by PCR-RFLP. Data were statistically analyzed by SPSS software using chi-square and ANOVA tests.   Findings: There was no relationship between the Apa1, Taq1 VDR polymorphism and BMD results. We found that patients with Taq1 genotype (tt) had lower bone mass in the femur and wrist compared with Tt.   Conclusion: Based on our findings, a relationship between the VDR polymorphism and osteoporosis remains unclear requiring further in-depth studies. Our results showed that other secondary factors may influence the bone mass density.