Association between osteoprotegerin gene polymorphism and bone mineral density in patients with adolescent idiopathic scoliosis

Abstract

Generalized low bone mass and osteopenia have been reported in the axial and peripheral skeleton of adolescent idiopathic scoliosis (AIS) patients. Recently, many studies have shown that gene polymorphisms are related to osteoporosis. However, no studies have linked the association between gene polymorphisms and bone mass of AIS. Therefore, this study examined the association between the bone mass and RANKL, RANK, and OPG gene polymorphisms in 198 girls diagnosed with AIS. OPG 163 A --> G, 209 G --> A, 245 T --> G, and 1181 G --> C polymorphisms; RANK 421 C --> T and 575 C --> T polymorphisms; and RANKL rs12721445 and rs2277438 polymorphisms, as well as the bone mineral density at the lumbar spine (LSBMD) and femoral neck (FNBMD) were analyzed. The 163 A --> G, 209 G --> A, and 245 T --> G polymorphisms in the OPG gene were in complete linkage. No RANK 421 C --> T and 575 C --> T polymorphisms or RANKL rs12711445 polymorphism were observed. There was a significant association between the OPG gene 1181 G --> C polymorphism and LSBMD. LSBMD in AIS with the CC genotype was found to be significantly higher than in AIS with the GC (P < 0.05) or GG (P < 0.01) genotype. However, there was no significant association between LSBMD or FNBMD and the OPG gene 245 T --> G polymorphism or the RANKL rs2277438 polymorphism. These results suggest that the OPG gene 1181 G --> C polymorphism is associated with LSBMD in girls with AIS.

Quantitative Assessment of the Association between Polymorphisms in Osteoprotegerin Gene and Risk of Low Bone Mineral Density

“…This data corroborates evidences in which G1181C polymorphism as well as CC genotype was associated to normal BMD in Korean patients with Adolescent Idiopathic Scoliosis [34]. A previous study demonstrated G allele and GG genotype carried out a bone mineral density 3.7% lower in women than women with CC genotype [35].…”

Polymorphism in vitamin D receptor is associated with bone mineral density in patients with adolescent idiopathic scoliosis

“…Adolescent idiopathic scoliosis patients have been reported to have a low bone mass and osteopenia in both the axial and peripheral skeletons [6,8,11,13,35,38]. However, the precise mechanism of bone loss in AIS patients is unclear.…”

“…Generalized low bone mass and osteopenia in both the axial and peripheral skeletons have been reported in AIS [7,8,11,13,35,38], and abnormal histomorphometric bone cell activity has been observed in AIS bone biopsies [9]. In addition, low bone mass is likely to persist through to adulthood in AIS patients [7], and there is increasing concern that adolescents with idiopathic scoliosis might have a lower peak bone mass, which would increase the risk of developing osteoporosis and related complications in later life [7,8].…”

Adolescent idiopathic scoliosis: evidence for intrinsic factors driving aetiology and progression

“…It is well established that central to the regulation of bone mass is osteoblast expression of receptor activator of nuclear factor kappa-B ligand (RANKL), which stimulates osteoclast activity and bone resorption by binding to RANK on the osteoclast membrane, and the osteoblast expression of osteoprotegerin (OPG), which acts as a decoy receptor for RANKL, thus inhibiting osteoclast activity and bone resorption [30]. Critically, genetic studies have shown associations between LSBMD with polymorphisms of OPG in girls diagnosed with AIS [16]. Furthermore, increased serum concentration of RANKL and an increase in the RANKL:OPG ratio, which would promote greater bone resorption, have been reported in patients with AIS, and were found to be negatively correlated to LSBMD [55].…”