Quantitative Assessment of the Association between Polymorphisms in Osteoprotegerin and Bone Mineral Density ORIGINAL

Background: Low bone mineral density (BMD) predisposes to osteoporosis and elevated risk of fractures. Osteoprotegerin is a soluble molecule associated to metabolism of bone tissue with inhibition of osteoclast-differentiation. Several studies determined the relation among polymorphisms in osteoprotegerin gene and low BMD, but the results are contradictory, so an evaluation about these polymorphisms is necessary. This study carried out a meta-analysis to four polymorphisms in osteoprotegerin gene (A163G, G1181C, T950C, T245G). Methods: A search in literature was made to identify studies with relevant information. The data was extracted by two investigators independently, following a standardized form. The statistical software Review Manager version 5.2 was used to calculation of heterogeneity (I²), Odds Ratio (OR) and Funnel plots with P<0.05. Results: Nineteen papers with twenty-one eligible studies with 5,120 patients and 4,386 controls were identified. G allele was associated to case group in A163G, G1181C and T245G polymorphisms (OR = 1.27, 95% CI 1.10, 1.46, P = 0.0010; OR = 1.25, 95% CI 1.14, 1.37, P < 0.00001; OR = 1.24, 95% CI 1.05, 1.48, P = 0.01, respectively). In T950C polymorphism, T allele neither C allele was associated to risk of bone low mineral density. No bias of publication was found in this analysis.