title: A single nucleotide polymorphism of interleukin-6 gene is related to plasma adrenomedullin levels.
abstract: OBJECTIVE
  Elevated plasma adrenomedullin (ADM) levels are associated with cardiovascular diseases. Single nucleotide polymorphisms (SNPs) in the gene encoding ADM (ADM) are associated with plasma ADM levels. The presence of a nuclear factor for interleukin-6 (IL-6) expression binding site in the promoter region of the ADM gene suggests a possible relationship between the expression of the ADM and IL-6. Therefore, we investigated whether plasma ADM levels are related to SNPs in the gene encoding IL-6 (IL6).
  
  
  METHODS
  Plasma ADM levels were measured in 476 subjects in the Hong Kong Cardiovascular Risk Factor Prevalence Study-2 (CRISPS2). The subjects were genotyped for three tagging SNPs in the IL6 gene.
  
  
  RESULTS
  The minor allele frequencies of the IL6 SNPs rs17147230, rs1800796 and rs2069837 were 41·8%, 20·0% and 15·4%, respectively. The tagging SNP, rs17147230, was associated with plasma ADM levels after adjusting for age and sex (β=-0·096, P = 0·034). The association was significant in women (β=-0·115, P = 0·021) but not in men. Among all subjects, plasma ADM levels decreased with an increasing number of minor alleles of rs17147230 in multivariate analysis (P = 0·034). Compared to subjects with the AA genotype, subjects with the TT genotype had plasma ADM levels 12·8% lower (95% CI: 0·6-23·5%, P = 0·041). Haplotype analysis demonstrated a significant association of the haplotype ACA with plasma ADM levels in women (P < 0·05).
  
  
  CONCLUSIONS
  Plasma ADM levels are related to the SNP rs17147230 in IL6 gene. The effect of the polymorphism on inflammation and cardiovascular disease remains to be determined.
authors.affiliation: Department of Medicine, University of Hong Kong, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong.
authors.forename: Hoi Kin
authors.initials: HK
authors.lastname: Wong
authors.forename: Kwok Leung
authors.initials: KL
authors.lastname: Ong
authors.forename: Raymond Y H
authors.initials: RY
authors.lastname: Leung
authors.forename: Tai Hing
authors.initials: TH
authors.lastname: Lam
authors.forename: Graham Neil
authors.initials: GN
authors.lastname: Thomas
authors.forename: Karen S L
authors.initials: KS
authors.lastname: Lam
authors.forename: Bernard M Y
authors.initials: BM
authors.lastname: Cheung
mesh_terms: D053607:Adrenomedullin / Q000097:blood*; D000328:Adult; D044466:Asian People / Q000235:genetics; D002318:Cardiovascular Diseases / Q000097:blood / Q000208:ethnology / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006239:Haplotypes; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D020641:Polymorphism, Single Nucleotide; D015995:Prevalence; D012307:Risk Factors; D012737:Sex Factors
chemical_list: D015850:Interleukin-6; D053607:Adrenomedullin