title: Occupational and genetic risk factors associated with intervertebral disc disease.
abstract: METHODS
  Cross-sectional epidemiologic study.
  
  
  OBJECTIVE
  To evaluate the interaction between known genetic risk factors and whole-body vibration for symptomatic intervertebral disc disease (IDD) in an occupational sample.
  
  
  BACKGROUND
  Risk factors of IDD include, among others, whole-body vibration and heredity. In this study, the importance of a set of known genetic risk factors and whole-body vibration was evaluated in an occupational sample of train engineers and sedentary controls.
  
  
  METHODS
  Eleven variations in 8 genes (COL9A2, COL9A3, COL11A2, IL1A, IL1B, IL6, MMP-3, and VDR) were genotyped in 150 male train engineers with an average of 21-year exposure to whole-body vibration and 61 male paper mill workers with no exposure to vibration. Subjects were classified into IDD-phenotype and asymptomatic groups, based on the latent class analysis.
  
  
  RESULTS
  The number of individuals belonging to the IDD-phenotype was significantly higher among train engineers (42% of train engineers vs. 17.5% of sedentary workers; P = 0.005). IL1A -889T allele represented a significant risk factor for the IDD-phenotype both in the single marker allelic association test (P = 0.043) and in the logistic regression analysis (P = 0.01). None of the other allele markers was significantly associated with symptoms when analyzed independently. However, for all the SNP markers considered, whole-body vibration represents a nominally significant risk factor.
  
  
  CONCLUSIONS
  The results suggest that whole-body vibration is a risk factor for symptomatic IDD. Moreover, whole-body vibration had an additive effect with genetic risk factors increasing the likelihood of belonging to the IDD-phenotype group. Of the independent genetic markers, IL1A -889T allele had strongest association with IDD-phenotype.
authors.affiliation: Collagen Research Unit, Biocenter and Department of Medical Biochemistry and Molecular Biology, University of Oulu, Oulu, Finland.
authors.forename: Iita M
authors.initials: IM
authors.lastname: Virtanen
authors.forename: Jaro
authors.initials: J
authors.lastname: Karppinen
authors.forename: Simo
authors.initials: S
authors.lastname: Taimela
authors.forename: Jürg
authors.initials: J
authors.lastname: Ott
authors.forename: Sandra
authors.initials: S
authors.lastname: Barral
authors.forename: Kaisu
authors.initials: K
authors.lastname: Kaikkonen
authors.forename: Olli
authors.initials: O
authors.lastname: Heikkilä
authors.forename: Pertti
authors.initials: P
authors.lastname: Mutanen
authors.forename: Noora
authors.initials: N
authors.lastname: Noponen
authors.forename: Minna
authors.initials: M
authors.lastname: Männikkö
authors.forename: Osmo
authors.initials: O
authors.lastname: Tervonen
authors.forename: Antero
authors.initials: A
authors.lastname: Natri
authors.forename: Leena
authors.initials: L
authors.lastname: Ala-Kokko
mesh_terms: D000328:Adult; D024081:Collagen Type IX / Q000235:genetics; D024161:Collagen Type XI / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000453:epidemiology*; D006801:Humans; D053582:Interleukin-1alpha / Q000235:genetics; D053583:Interleukin-1beta / Q000235:genetics; D015850:Interleukin-6 / Q000235:genetics; D007405:Intervertebral Disc Displacement / Q000453:epidemiology* / Q000235:genetics*; D016015:Logistic Models; D008297:Male; D019278:Matrix Metalloproteinase 3 / Q000235:genetics; D008875:Middle Aged; D009784:Occupational Diseases / Q000453:epidemiology* / Q000235:genetics*; D016273:Occupational Exposure; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D011890:Railroads; D018167:Receptors, Calcitriol / Q000235:genetics; D012307:Risk Factors; D014732:Vibration
chemical_list: C499319:COL11A2 protein, human; C120282:COL9A2 protein, human; C120768:COL9A3 protein, human; D024081:Collagen Type IX; D024161:Collagen Type XI; C508584:IL1A protein, human; C508585:IL1B protein, human; C508600:IL6 protein, human; D053582:Interleukin-1alpha; D053583:Interleukin-1beta; D015850:Interleukin-6; D018167:Receptors, Calcitriol; D019278:Matrix Metalloproteinase 3