title: A haplotype at the COL9A2 gene locus contributes to the genetic risk for lumbar spinal stenosis in the Korean population.
abstract: METHODS
  We conducted a cross-sectional, genotyping study in patients with lumbar spinal stenosis (LSS) and controls.
  
  
  OBJECTIVE
  To determine the contribution of COL9A2 polymorphisms to LSS development in the Korean population.
  
  
  BACKGROUND
  Because congenital spinal stenosis is typically associated with chondrodysplasias, which are genetic disorders, genetic factors may also play a role in degenerative LSS. A recent Finnish study reported a splice site mutation in COL9A2, leading to premature translation termination. However, a few studies on the genetic association of single nucleotide polymorphisms (SNPs) or haplotypes with LSS have appeared.
  
  
  METHODS
  We studied 205 symptomatic patients with radiographically proven LSS and 101 volunteers with no history of back problems from our institution. Magnetic resonance images were obtained for all the patients and controls. Quantitative image evaluation for LSS was performed to evaluate the severity of LSS. All patients and controls were genotyped for COL9A2 allele variations, using a polymerase chain reaction-based technique.
  
  
  RESULTS
  We found no causal SNPs in COL9A2 that were significantly associated with LSS, even after phenotypic subgrouping. Haplotype analysis showed that the "GCAGCG" haplotype (HAP2) was overrepresented in LSS patients (P = 0.023, odds ratio [OR] = 1.86), especially in those with severe stenosis (P = 0.018, OR = 1.98). In addition, the "TCAGCG" haplotype (HAP4) was overrepresented in controls (P = 0.042, OR = 0.52).
  
  
  CONCLUSIONS
  Although no SNPs in COL9A2 were associated with LSS, a COL9A2 haplotype (HAP2) was significantly associated with LSS in the Korean population, whereas another haplotype (HAP4) may play a protective role against LSS development. However, the genetic functions of COL9A2 haplotypes in LSS remain to be determined.
authors.affiliation: Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Hyun
authors.forename: Borae G
authors.initials: BG
authors.lastname: Park
authors.forename: Seung-Chul
authors.initials: SC
authors.lastname: Rhim
authors.forename: Chae Wan
authors.initials: CW
authors.lastname: Bae
authors.forename: Jong-Keuk
authors.initials: JK
authors.lastname: Lee
authors.forename: Sung-Woo
authors.initials: SW
authors.lastname: Roh
authors.forename: Sang-Ryong
authors.initials: SR
authors.lastname: Jeon
mesh_terms: D000328:Adult; D000368:Aged; D044466:Asian People / Q000235:genetics; D001483:Base Sequence; D024081:Collagen Type IX / Q000235:genetics*; D003430:Cross-Sectional Studies; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D011859:Radiography; D056910:Republic of Korea; D012307:Risk Factors; D013130:Spinal Stenosis / Q000208:ethnology / Q000235:genetics* / Q000473:pathology
chemical_list: C120282:COL9A2 protein, human; D024081:Collagen Type IX