A single-nucleotide polymorphism rs708567 in the IL-17RC gene is associated with a susceptibility to and the curve severity of adolescent idiopathic scoliosis in a Chinese Han population: a case-control study

Abstract

BackgroundAlthough the pathogenesis of adolescent idiopathic scoliosis (AIS) remains controversial, genetic factors are thought to play key roles in the development of AIS. In a recent genome-wide association study, a polymorphism in the interleukin-17 receptor C (IL-17RC) gene was reported to be associated with the susceptibility to AIS, implicating IL-17RC as a novel predisposing gene for AIS. However, as this association has not been replicated in other populations, its global applicability remains unclear.MethodsA total of 529 Chinese girls with AIS and 512 healthy age-matched controls were recruited in this case–control study from June 2007 to December 2009. Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis was performed to detect the genotype of the single-nucleotide polymorphism (SNP) rs708567 in the IL-17RC gene. Case–control and case-only studies were performed to determine the association between the IL-17RC gene polymorphism and the susceptibility to and curve severity of AIS.ResultsThe GG genotype and G allele frequencies were significantly higher in the AIS patients than in the controls (χ2 test: P = 0.023 and 0.028, respectively). The risk for the GG genotype is 1.550-fold (95% CI: 1.062 - 2.261) higher than the AG genotype, and the risk for the G allele is 1.507-fold (95% CI: 1.046 - 2.172) higher than the A allele. Additionally, a subgroup of skeletally mature AIS patients (n = 241) who carried the GG genotype showed a significantly higher mean maximum Cobb angle than those carrying the AG genotype (36.01 ± 13.12° vs. 28.92 ± 7.43°, P = 0.007).ConclusionsThis study confirms the significant association between the IL-17RC gene polymorphism and the susceptibility to and curve severity of AIS in a Chinese Han population, suggesting that the IL-17RC gene is an AIS-predisposing gene in Chinese Han population.