Is there any relation between IL-6 gene −174 G>C polymorphism and postmenopausal osteoporosis?

ObjectiveIL-6 gene single nucleotide polymorphisms (SNPs) have been reported to have a protective effect against bone resorption. We aimed to investigate the association between bone mineral density and IL-6 promoter region −174 G>C SNP.Study designThis study included 356 postmenopausal Turkish women, of whom 201 were osteoporotic (lumbar spine T score < −2.5 SD) and 155 non-osteoporotic (lumbar spine T score > −1.5 SD). Bone mineral density (BMD) measures were obtained using dual-energy X-ray absorptiometry. SNP of the IL-6 gene (−174 G>C) was examined by polymerase chain reaction-restriction fragment length polymorphism.ResultsThe frequencies of the variant C allele (24% vs. 30%, p = 0.074) and mutant CC genotype (12% vs. 20%, p = 0.094) were higher in non-osteoporotic women. Lumbar spine and total hip BMD values were lowest among women with the G/G genotype, intermediate in the heterozygotes, and highest in women with the C/C genotype. The GG (p = 0.022) and GC (p = 0.037) genotypes were covariates which approached statistical significance in the regression model fitting of BMD.ConclusionIL-6 promoter region SNP showed an association with BMD in this postmenopausal Turkish population and these data suggest that the wild GG genotype influences the phenotype.