A Replication Study for Association of 5 Single Nucleotide Polymorphisms With Curve Progression of Adolescent Idiopathic Scoliosis in Japanese Patients

Study Design. A genetic association study of single nucleotide polymorphisms (SNPs) previously reported to be associated with curve progression of adolescent idiopathic scoliosis (AIS). Objective. To determine whether the association of 5 SNPs with curve progression reported in Chinese with AIS are replicated in Japanese patients with AIS. Summary of Background Data. AIS is a common spinal deformity and has a strong genetic predisposition. Predicting curve progression is important in clinical practice. The progression of AIS is reported to be associated with a number of genes. Associations with neurotrophin 3, G protein-coupled estrogen receptor, and tissue inhibitor of metalloproteinase 2 have been reported in Han Chinese with AIS; however, there has been no replication study for them. Methods. We recruited 2117 patients with AIS with a Cobb angle of 10 degrees or greater of scoliosis curves. They were grouped into progression and nonprogression groups according to their scoliosis curves. Patients whose scoliotic curves were 40 degrees or greater were included in the progression group, and those whose scoliotic curves were less than 30 degrees and had reached skeletal maturation in the nonprogression group. We evaluated the association of 5 SNPs (rs11063714 in neurotrophin 3, rs3808351, rs10269151, and rs4266553 in G protein-coupled estrogen receptor, and rs8179090 in tissue inhibitor of metalloproteinase 2 with curve progression by comparing risk allele frequencies between the 2 groups and the mean Cobb angle for each genotype. Results. We evaluated the progression (N = 880) and nonprogression (N = 492) subjects, and their risk allele frequencies were not significantly different. The mean Cobb angle for each genotype also did not have statistical difference. We found no replication of the association on AIS curve progression in any of the SNPs. Conclusion. The associations of the 5 SNPs with progression of AIS curve are not definite. Large-scale association studies based on appropriate criteria for progression would be necessary to identify SNPs associated with the curve progression.