title: Association of longevity with TNF-α G308A and IL-6 G174C polymorphic inflammatory biomarkers in Caucasians: a meta-analysis.
abstract: BACKGROUND
  Mutations in genes encoding tumor necrosis factor (TNF)-α and interleukin (IL)-6 were previously shown to affect mortality. Single nucleotide polymorphisms (SNPs) in the functional promoter regions of TNF-α (G308A) and IL-6 (G174C) are among the most widely studied.
  
  
  OBJECTIVE
  To determine whether TNF-α G308A and IL-6 G174C SNPs confer susceptibility to longevity, we performed a meta-analysis to comprehensively estimate the association between these SNPs and longevity in long-lived individuals (LLI, aged ≥ 80 years).
  
  
  METHODS
  Studies addressing the role of TNF-α and IL-6 SNPs in longevity were identified from the PubMed database. Pooled ORs with 95 % confidence intervals (CIs) were used to assess the association between SNPs and longevity.
  
  
  RESULTS
  The meta-analysis was based on four studies of TNF-α G308A and nine of IL-6 G174C, covering a total of 2945 LLI individuals and 2992 controls. Overall, no significantly increased risks were observed for G308A [A vs. G (additive model): OR = 0.98, 95 % CI = 0.79-1.22, p = 0.852; AA + AG vs. GG (dominant model): OR = 0.97, 95 % CI = 0.75-1.24, p = 0.791] or for G174C [C vs. G (additive model): OR = 1.07, 95 % CI = 0.94-1.22, p = 0.293; CC + CG vs. GG (dominant model): OR = 1.09, 95 % CI = 0.93-1.28, p = 0.299]. There was no change in the significance when a cutoff age of ≥ 90 years was introduced.
  
  
  CONCLUSIONS
  We found no evidence that the TNF-α G308A and IL-6 G174C SNPs affected the probability of reaching an advanced age in Caucasians, and that they have little effect on delaying the onset and progression of age-related diseases, but this does not rule out the possibility of population-specific effects caused by different genes and/or environmental factors and their interactions.
authors.affiliation: Laboratory of Molecular Genetics of Aging and Tumor, Medical Faculty, Kunming University of Science and Technology, Chenggong Campus, 727 South Jingming Road, Kunming, 650500, Yunnan, China.
authors.forename: Gan-Zhong
authors.initials: GZ
authors.lastname: Wei
authors.affiliation: Laboratory of Molecular Genetics of Aging and Tumor, Medical Faculty, Kunming University of Science and Technology, Chenggong Campus, 727 South Jingming Road, Kunming, 650500, Yunnan, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.affiliation: Laboratory of Molecular Genetics of Aging and Tumor, Medical Faculty, Kunming University of Science and Technology, Chenggong Campus, 727 South Jingming Road, Kunming, 650500, Yunnan, China.
authors.forename: Yue-Guang
authors.initials: YG
authors.lastname: Zhao
authors.affiliation: Laboratory of Molecular Genetics of Aging and Tumor, Medical Faculty, Kunming University of Science and Technology, Chenggong Campus, 727 South Jingming Road, Kunming, 650500, Yunnan, China.
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Li
authors.affiliation: Laboratory of Molecular Genetics of Aging and Tumor, Medical Faculty, Kunming University of Science and Technology, Chenggong Campus, 727 South Jingming Road, Kunming, 650500, Yunnan, China.
authors.forename: Min-Ling
authors.initials: ML
authors.lastname: Shi
authors.affiliation: Laboratory of Molecular Genetics of Aging and Tumor, Medical Faculty, Kunming University of Science and Technology, Chenggong Campus, 727 South Jingming Road, Kunming, 650500, Yunnan, China.
authors.forename: Kang
authors.initials: K
authors.lastname: Gao
authors.affiliation: Laboratory of Molecular Genetics of Aging and Tumor, Medical Faculty, Kunming University of Science and Technology, Chenggong Campus, 727 South Jingming Road, Kunming, 650500, Yunnan, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Laboratory of Molecular Genetics of Aging and Tumor, Medical Faculty, Kunming University of Science and Technology, Chenggong Campus, 727 South Jingming Road, Kunming, 650500, Yunnan, China. twr@sina.com.
authors.forename: Wen-Ru
authors.initials: WR
authors.lastname: Tang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D056726:Genetic Association Studies; D005819:Genetic Markers / Q000235:genetics; D006801:Humans; D007249:Inflammation / Q000208:ethnology / Q000235:genetics*; D015850:Interleukin-6 / Q000235:genetics*; D008136:Longevity / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*; D044465:White People / Q000235:genetics* / Q000706:statistics & numerical data*
chemical_list: D005819:Genetic Markers; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha
keywords: Alleles; Caucasians; Genetics of aging; Genotype; Older patients