Association analysis between A163G and T245G gene polymorphisms of osteoprotegerin and bone mineral density in Turkish postmenopausal women

Abstract

Osteoprotegerin (OPG) is one of the most important candidate genes associated with osteoporosis predisposition. The aim of the present study was to evaluate the relationship between bone mineral density (BMD) and two polymorphisms in the OPG promoter, namely A163G and T245G among postmenopausal women. Material and Methods: A total of 109 women with postmenopausal osteoporosis and 85 healthy controls were included in the study. BMD of L1, L4, total lumbar spine (L1-4), neck, hip and total hip were evaluated by means of dual-energy X-ray absorptiometry. A163G and T245G polymorphisms were determined by PCR and RFLP. Results: The frequencies of genotypes were as follows: AG+GG (46.8%), AA (53.2%) for A163G and GG+TG (36.7%), TT (63.3%) for T245G. Compared to healthy women, remarkably more women with osteoporosis were found to have AG+GG (p=0.005) and GG+TG (p=0.049). Significant associations were observed between the genotypes and BMD of lumbar spine for the T245G and A163G polymorphisms in postmenopausal women and controls (p˂0.05 for all). The GG+TG genotypes correlated with lower BMD compared to TT for T245G. Similarly, for A163G, the AG+GG genotypes were associated with lower BMD compared to AA. Conclusion: Our results suggest that T245G and A163G polymorphisms in the OPG promoter may contribute to the genetic regulation of BMD. These results are expected to be beneficial for further studies investigating the role of OPG in osteoporosis.