Project description:Adolescent idiopathic scoliosis (AIS) is the most common spinal deformity, affecting around 2% of adolescents worldwide. Genetic factors play an important role in its etiology. Using a genome-wide association study (GWAS), we recently identified novel AIS susceptibility loci on chromosomes 10q24.31 and 6q24.1. To identify more AIS susceptibility loci relating to its severity and progression, we performed GWAS by limiting the case subjects to those with severe AIS. Through a two-stage association study using a total of ?12,000 Japanese subjects, we identified a common variant, rs12946942 that showed a significant association with severe AIS in the recessive model (P=4.00 × 10(-8), odds ratio [OR]=2.05). Its association was replicated in a Chinese population (combined P=6.43 × 10(-12), OR?=?2.21). rs12946942 is on chromosome 17q24.3 near the genes SOX9 and KCNJ2, which when mutated cause scoliosis phenotypes. Our findings will offer new insight into the etiology and progression of AIS.
Project description:Adolescent idiopathic scoliosis (AIS) is a common disorder with strong evidence for genetic predisposition. Quantitative trait loci (QTLs) for AIS susceptibility have been identified on chromosomes. We performed a genome-wide genetic linkage scan in seven multiplex families using 400 marker loci with a mean spacing of 8.6 cM. We used Genehunter Plus to generate linkage statistics, expressed as homogeneity (HLOD) scores, under dominant and recessive genetic models. We found a significant linkage signal on chromosome 12p, whose support interval extends from near 12 pter, spanning approximately 10 million bases or 31 cM. Fine mapping within the region using 20 additional markers reveals maximum HLOD = 3.7 at 5 cM under a dominant inheritance model, and a split peak maximum HLOD = 3.2 at 8 and 18 cM under a recessive inheritance model. The linkage support interval contains 95 known genes. We found evidence suggestive of linkage on chromosomes 1, 6, 7, 8, and 14. This study is the first to find evidence of an AIS susceptibility locus on chromosome 12. Detection of AIS susceptibility QTLs on multiple chromosomes in this and other studies demonstrate that the condition is genetically heterogeneous.
Project description:Adolescent idiopathic scoliosis (AIS) is one of the most common orthopedic disorders, affecting up to 4% of schoolchildren worldwide. We studied seven unrelated multiplex families of southern Chinese descent with AIS, consisting of 25 affected members. A genomewide scan with >400 fluorescent microsatellite markers was performed. Multipoint linkage analysis by GENEHUNTER revealed significant linkage of the abnormal phenotype to the distal short arm of chromosome 19, with both a maximum multipoint LOD score and a nonparametric LOD score of 4.93. Two-point linkage analysis by MLINK gave a LOD score of 3.63 (recombination fraction theta[m=f]=0.00) at D19S216. Further high-density mapping and informative recombinations defined the AIS critical region in the vicinity of D19S216, flanked by D19S894 and D19S1034, spanning 5.2 cM on the sex-averaged genetic map on chromosome 19p13.3.
Project description:ObjectiveTo investigate whether: (i) rs12885713 (-16C > T) and rs5871 polymorphisms in the Calmodulin1 (CALM1) gene are predisposing factors for adolescent idiopathic scoliosis (AIS); and (ii) different single nucleotide polymorphisms (SNP) correlate with different subtypes of AIS.MethodsA total of 100 AIS patients with Cobb angle above 30° were recruited for this study together with 100 healthy controls. Curve pattern, Cobb angle, and Risser sign were recorded. Two polymorphic loci, rs12885713 (-16C > T) and rs5871 loci, of the CALM1 gene were analyzed. All patients were grouped according to the Peking Union Medical College (PUMC) classification, the apical location of the major curve, and the Cobb angle.ResultsThere was a statistically significant difference in the distribution of rs12885713 site polymorphism (P = 0.034) between PUMC type II (double curve) patients and controls, in the distribution of rs12885713 site polymorphism (P = 0.009) between lumbar curve cases and controls and in the distribution of rs5871 site polymorphism (P = 0.035) between thoracic curve patients and controls.ConclusionDifferent subtypes of AIS might be related to different SNP. The susceptibility of PUMC type II (double curve) AIS and lumbar curve might be related to CALM1 rs12885713 site polymorphism, while rs5871 site polymorphism might be a risk indicator for thoracic curve cases.
Project description:Adolescent idiopathic scoliosis (AIS) is an unexplained and common spinal deformity seen in otherwise healthy children. Its pathophysiology is poorly understood despite intensive investigation. Although genetic underpinnings are clear, replicated susceptibility loci that could provide insight into etiology have not been forthcoming. To address these issues, we performed genome-wide association studies (GWAS) of ?327 000 single nucleotide polymorphisms (SNPs) in 419 AIS families. We found strongest evidence of association with chromosome 3p26.3 SNPs in the proximity of the CHL1 gene (P < 8 × 10(-8) for rs1400180). We genotyped additional chromosome 3p26.3 SNPs and tested replication in two follow-up case-control cohorts, obtaining strongest results when all three cohorts were combined (rs10510181 odds ratio = 1.49, 95% confidence interval = 1.29-1.73, P = 2.58 × 10(-8)), but these were not confirmed in a separate GWAS. CHL1 is of interest, as it encodes an axon guidance protein related to Robo3. Mutations in the Robo3 protein cause horizontal gaze palsy with progressive scoliosis (HGPPS), a rare disease marked by severe scoliosis. Other top associations in our GWAS were with SNPs in the DSCAM gene encoding an axon guidance protein in the same structural class with Chl1 and Robo3. We additionally found AIS associations with loci in CNTNAP2, supporting a previous study linking this gene with AIS. Cntnap2 is also of functional interest, as it interacts directly with L1 and Robo class proteins and participates in axon pathfinding. Our results suggest the relevance of axon guidance pathways in AIS susceptibility, although these findings require further study, particularly given the apparent genetic heterogeneity in this disease.
Project description:Idiopathic scoliosis (IS) is a common paediatric musculoskeletal disease that displays a strong female bias. By performing a genome-wide association study (GWAS) of 3,102 individuals, we identify significant associations with 20p11.22 SNPs for females (P=6.89 × 10(-9)) but not males (P=0.71). This association with IS is also found in independent female cohorts from the United States of America and Japan (overall P=2.15 × 10(-10), OR=1.30 (rs6137473)). Unexpectedly, the 20p11.22 IS risk alleles were previously associated with protection from early-onset alopecia, another sexually dimorphic condition. The 174-kb associated locus is distal to PAX1, which encodes paired box 1, a transcription factor involved in spine development. We identify a sequence in the associated locus with enhancer activity in zebrafish somitic muscle and spinal cord, an activity that is abolished by IS-associated SNPs. We thus identify a sexually dimorphic IS susceptibility locus, and propose the first functionally defined candidate mutations in an enhancer that may regulate expression in specific spinal cells.
Project description:Genome-wide association studies have identified many susceptibility genes for adolescent idiopathic scoliosis (AIS). However, most of the results are hard to be replicated in multi-ethnic populations. LBX1 is the most promising candidate gene in the etiology of AIS. We aimed to appraise the literature for the association of LBX1 gene polymorphisms with susceptibility and curve progression in AIS. We also reviewed the function of the LBX1 gene in muscle progenitor cell migration and neuronal determination processes. Three susceptibility loci (rs11190870, rs625039, and rs11598564) near the LBX1 gene, as well as another susceptibility locus (rs678741), related to LBX1 regulation, have been successfully verified to have robust associations with AIS in multi-ethnic populations. The LBX1 gene plays an essential role in regulating the migration and proliferation of muscle precursor cells, and it is known to play a role in neuronal determination processes, especially for the fate of somatosensory relay neurons. The LBX1 gene is the most promising candidate gene in AIS susceptibility due to its position and possible functions in muscle progenitor cell migration and neuronal determination processes. The causality between susceptibility loci related to the LBX1 gene and the pathogenesis of AIS deserves to be explored with further integrated genome-wide and epigenome-wide association studies.
Project description:Plasma exosomal miRNA may differ between adolescent idiopathic scoliosis patients and healthy individuals. Sequencing analysis was used to find these differential miRNAs.
Project description:Adolescent Idiopathic Scoliosis (AIS) is the most common orthopedic condition requiring surgery, affecting 4% of adolescents. There is currently no proven method or prognostic test to identify symptomatic patients at risk of developing severe scoliosis who could benefit from growth-guided devices or minimally invasive non-fusion instrumentation surgeries. These innovative treatments must be performed at an early disease stage in younger patients to benefit from their growth potential. In this prospective cross-sectional study, we investigated the clinical utility of circulating microRNAs (miRNAs), an important class of small non-coding RNA, as biomarkers to predict the risk of developing severe scoliosis in AIS. Blood samples and clinical data were collected from 116 AIS patients who were followed until skeletal maturity and stratified according to their clinical outcome. Genome-wide expression profiling of miRNAs was performed with plasma obtained at the time of diagnosis of AIS (mean age of 13.3 ± 1.7 years with a mean Cobb angle of 24.4° ± 12.4°). This approach led to the identification of 15 circulating miRNAs that are upregulated in AIS patients who developed a severe scoliosis (Cobb angle ≥45°) at skeletal maturity compared to moderate and mild scoliosis groups (Cobb angle between 25°-44° and <25° respectively). After optimization and the application of Random Forest Models a panel of six miRNAs (miR-1-3p, miR-19a-3p, miR-19b-3p, miR-133b, miR-143-3p, and miR-148b-3p) out of 15 led us to develop an algorithm predicting the risk of developing a severe scoliosis with great accuracy (100%), sensitivity (100%) and specificity (100%). Having a scoliosis predictive bioassay and decision-making tools to predict curve progression in order to find the best treatment plan will undoubtedly transform the orthopedic care system in the field of pediatric scoliosis by integrating innovative precision medicine approaches. In addition, investigation of genes targeted by these miRNAs could fill our gaps in our understanding of AIS pathogenesis and reveal new actionable targets.
Project description:ObjectiveIdiopathic scoliosis is the most common pediatric spinal deformity affecting 1% to 3% of the population, and adolescent idiopathic scoliosis (AIS) accounts for approximately 80% of these cases; however, the etiology and pathogenesis of AIS are still uncertain. The current study aims to identify the relationship between calmodulin 1 (CALM1) gene and AIS predisposition, to identify the relationship between the genotypes of the SNPs and the clinical phenotypes of AIS.Methods146 AIS patients and 146 healthy controls were enrolled into this case-control study. 12 single nucleotide polymorphisms (SNPs) candidates in CALM1 gene were selected to determine the relationship between CALM1 gene and AIS predisposition. Case-only study was performed to determine the effects of these variants on the severity of the condition.ResultsThree SNPs from 12 candidates were found to be associated with AIS predisposition. The ORs were observed as 0.549 (95% CI 0.3519-0.8579, P = 0.0079), 0.549 (95% CI 0.3519-0.8579, P = 0.0079), and 1.6139 (95% CI 1.0576-2.4634, P = 0.0257) for rs2300496, rs2300500, and rs3231718, respectively. There was no statistical difference between main curve, severity, and genotype distributions of all of 12 SNPs.ConclusionGenetic variants of CALM1 gene are associated with AIS susceptibility.