title: The association of the 174G>C polymorphism of interleukin 6 gene with diabetic nephropathy in patients with type 2 diabetes mellitus.
abstract: OBJECTIVE
  To evaluate the association of 174G>C polymorphism on interleukin-6 (IL-6) gene with diabetic nephropathy in patients with type 2 diabetes.
  
  
  METHODS
  A total of 393 Greek subjects with type 2 diabetes (mean age 66.5±10.0years, men n=203, women n=190) were examined. Diabetic nephropathy was defined as presence of microalbuminuria and/or proteinuria. The IL-6 174G>C polymorphism was detected by polymerase chain reaction and appropriate restriction enzyme digestion. High sensitivity C-reactive protein was assayed by particle-enhanced immunonephelometry.
  
  
  RESULTS
  The genotype distribution (%) was GG: 49.1, GC: 26.8 and CC: 24.1, with no gender difference. The CC homozygotes had lower albumin excretion (mg/24h) in comparison with the GC genotype [CC: 8.9 (4.0-20.9) vs GC: 21.95 (9.1-53.35), P=0.004]. Participants with the GC genotype tended to have more frequently nephropathy than those with the GG or the CC genotype [GC: 44.55% vs GG: 35.1% and CC: 28.3%, P=0.07)]. The CC homozygotes in comparison with GC heterozygotes had lower odds to have nephropathy (odds ratio: 0.51, 95% confidence intervals=0.28-0.91, P=0.02), even after adjustment for sex, age, duration of diabetes, body mass index, smoking, hypertension, lipids and glycated hemoglobin, (P=0.01).
  
  
  CONCLUSIONS
  In type 2 diabetes states, CC homozygotes have lower albumin excretion and are protected from nephropathy in comparison with GC genotypes.
authors.affiliation: 1st Department of Propaedeutic and Internal Medicine, Athens University Medical School, Laiko General Hospital, Greece. Electronic address: drstpapaoikonomou@yahoo.gr.
authors.forename: Stavroula
authors.initials: S
authors.lastname: Papaoikonomou
authors.forename: Nicholas
authors.initials: N
authors.lastname: Tentolouris
authors.forename: Dimitris
authors.initials: D
authors.lastname: Tousoulis
authors.forename: Dimitris
authors.initials: D
authors.lastname: Papadodiannis
authors.forename: Antigoni
authors.initials: A
authors.lastname: Miliou
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Papageorgiou
authors.forename: George
authors.initials: G
authors.lastname: Hatzis
authors.forename: Christodoulos
authors.initials: C
authors.lastname: Stefanadis
mesh_terms: D000368:Aged; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000453:epidemiology / Q000235:genetics*; D003928:Diabetic Nephropathies / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6
keywords: Diabetic nephropathy; Gene polymorphism association study; Interleukin-6 174G>C polymorphism