title: COL9A1 gene polymorphism is associated with Kashin-Beck disease in a northwest Chinese Han population.
abstract: OBJECTIVE
  We sought to determine whether genomic polymorphism in collagen IX genes (COL9A) was associated with Kashin-Beck disease (KBD).
  
  
  METHODS
  Twenty seven single nucleotide polymorphisms (SNPs) in COL9AI, COL9A2 and COL9A3 were genotyped in 274 KBD cases and 248 healthy controls using the Sequenom MassARRAY system. Associations between the COL9A polymorphism and KBD risk were detected using an unconditional logistic regression model. Linkage disequilibrium (LD) and haplotypes analysis were performed with the Haploview software.
  
  
  RESULTS
  After Bonferroni correction, the frequency distribution of genotypes in rs6910140 in COL9A1 was significantly different between the KBD and the control groups (X2 = 16.74, df = 2, P = 0.0002). Regression analysis showed that the allele "C" in SNP rs6910140 had a significant protective effect on KBD [odds ratio (OR) = 0.49, 95% confidence interval (CI) = 0.34-0.70, P = 0.0001]. The frequencies of alleles and genotypes in rs6910140 were significantly different among subjects of different KBD stages (allele: X2 = 7.82, df = 2, P = 0.02, genotype: X2 = 14.81, df = 4, P = 0.005). However, haplotype analysis did not detect any significant association between KBD and COL9A1, COL9A2 and COL9A3.
  
  
  CONCLUSIONS
  We observed a significant association between rs6910140 of COL9A1 and KBD, suggesting a role of COL9A1 in the development of KBD.
authors.affiliation: Center of Maternal and Child Health Care, The First Affiliated Hospital of Medical Collage of Xi'an Jiaotong University, Xi'an, Shannxi, PR of China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Shi
authors.affiliation: School of Public Health, Health Science Center, Xi'an Jiaotong University, Key Laboratory of Environment and Gene Related Diseases of Ministry of Education, Key Laboratory of Trace Elements and Endemic Diseases of Ministry of Health, Xi'an, Shannxi, PR of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhang
authors.affiliation: School of Public Health, Health Science Center, Xi'an Jiaotong University, Key Laboratory of Environment and Gene Related Diseases of Ministry of Education, Key Laboratory of Trace Elements and Endemic Diseases of Ministry of Health, Xi'an, Shannxi, PR of China.
authors.forename: Aili
authors.initials: A
authors.lastname: Lv
authors.affiliation: School of Public Health, Health Science Center, Xi'an Jiaotong University, Key Laboratory of Environment and Gene Related Diseases of Ministry of Education, Key Laboratory of Trace Elements and Endemic Diseases of Ministry of Health, Xi'an, Shannxi, PR of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wen
authors.affiliation: School of Public Health, Health Science Center, Xi'an Jiaotong University, Key Laboratory of Environment and Gene Related Diseases of Ministry of Education, Key Laboratory of Trace Elements and Endemic Diseases of Ministry of Health, Xi'an, Shannxi, PR of China.
authors.forename: Xiong
authors.initials: X
authors.lastname: Guo
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D024081:Collagen Type IX / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D057767:Kashin-Beck Disease / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D012720:Severity of Illness Index
chemical_list: C439970:COL9A1 protein, human; C120282:COL9A2 protein, human; C120768:COL9A3 protein, human; D024081:Collagen Type IX