title: DNA variants, plasma levels and variability of interleukin-6 in myocardial infarction survivors: results from the AIRGENE study.
abstract: BACKGROUND
  Increased levels of interleukin 6 (IL-6), a marker for systemic inflammation, have been associated with cardiovascular morbidity and mortality.
  
  
  METHODS
  We investigated the influence of IL6 gene polymorphisms on mean level and variability of plasma IL-6 in a population of myocardial infarction survivors recruited in six European cities as part of the AIRGENE study. DNA from each individual was collected and genotyped for eight functional and tagging single nucleotide polymorphisms (SNPs) in the IL6 gene.
  
  
  RESULTS
  We analyzed 946 subjects with 5520 repeated plasma samples for IL-6 levels. For four IL6 SNPs in high linkage disequilibrium, heterozygous and homozygous minor allele genotypes were associated with an increase in mean plasma IL-6 levels. SNP rs1800795 was associated with a 6.3% increase in IL-6 (95% confidence interval [CI] 1.7-11,2%) For these SNPs, we found that genotypes associated with higher IL-6 levels also tended to be associated to higher between-individual variability of IL-6 levels on the log-scale than other genotypes. Variability over time within individuals varied little by genotype.
  
  
  CONCLUSIONS
  We found four genetic polymorphisms in the IL6 gene associated with mean level and variability of plasma IL-6 between individuals in myocardial infarction survivors.
authors.affiliation: Dept of Cardiology, Karolinska Institutet, Stockholm South Hospital, Stockholm, Sweden. petter.ljungman@ki.se
authors.forename: Petter
authors.initials: P
authors.lastname: Ljungman
authors.forename: Tom
authors.initials: T
authors.lastname: Bellander
authors.forename: Fredrik
authors.initials: F
authors.lastname: Nyberg
authors.forename: Erik
authors.initials: E
authors.lastname: Lampa
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Jacquemin
authors.forename: Melanie
authors.initials: M
authors.lastname: Kolz
authors.forename: Timo
authors.initials: T
authors.lastname: Lanki
authors.forename: John
authors.initials: J
authors.lastname: Mitropoulos
authors.forename: Martina
authors.initials: M
authors.lastname: Müller
authors.forename: Sally
authors.initials: S
authors.lastname: Picciotto
authors.forename: Riccardo
authors.initials: R
authors.lastname: Pistelli
authors.forename: Regina
authors.initials: R
authors.lastname: Rückerl
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Koenig
authors.forename: Annette
authors.initials: A
authors.lastname: Peters
mesh_terms: D000368:Aged; D000483:Alleles; D015415:Biomarkers / Q000097:blood; D002947:Cities; D004247:DNA / Q000235:genetics*; D016208:Databases, Factual; D005060:Europe; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006239:Haplotypes; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D015810:Linkage Disequilibrium; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012042:Registries; D044465:White People / Q000235:genetics
chemical_list: D015415:Biomarkers; D015850:Interleukin-6; D004247:DNA