Effect of osteoprotegerin gene polymorphism on bone mass in postmenopausal women

Abstract

To investigate the effect of promoter region polymorphism of osteoprotegerin (OPG) gene on bone mineral density (BMD) and markers of bone turnover in postmenopausal women. The OPG genotype were determined by PCR-RFLP in 259 postmenopausal women of Han race in Shanghai area, and BMD at lumbar-spine, femoral neck, trochanter and Ward's triangle etc., were measured by dual-energy X-ray absorptiometry (DEXA). Some markers of bone turnover were also detected. Hardy-Weinberg equilibrium was evident for OPG polymorphism. The frequency of the genotype is as following: TT59%, TC28%, CC13%. Postmenopausal women were divided into two groups. Women aged less than 65 years old were in group I, and aged 65 years old and over were in group II. In group I the BMD at femur neck area was 0.64 g/cm(2) +/- 0.11 g/cm(2), 0.67 g/cm(2) +/- 0.11 g/cm(2), 0.68 g/cm(2) +/- 0.14 g/cm(2) of TT, TC, CC genotypes respectively, among which a significant difference was observed (P < 0.05 by ANOVA), and the significant difference also presented after adjusted by age and BMI, but not found the significant difference in other markers. In group II, significant link was not observed between OPG polymorphism and BMD with markers of bone turnover. OPG polymorphism may have an effect on the BMD of postmenopausal women aged less than 65. It is possibly that the role of OPG gene mainly on the obtaining of peak BMD in women.