Association of tumor necrosis factor alpha promoter polymorphism (TNF-α 238 G/A and TNF-α 308 G/A) with diabetic mellitus, diabetic retinopathy and diabetic nephropathy: a meta-analysis.
OBJECTIVE
To examine the association between tumor necrosis factor alpha (TNF-α) polymorphism and risk for diabetic mellitus (DM), diabetic retinopathy (DR) and diabetic nephropathy (DN).


METHODS
Systematic searches of electronic databases such as PubMed, Medline, Web of knowledge and CNKI, as well as hand searching of the references of identified articles were performed. A total of 8979 subjects in 14 studies from 12 eligible publications were included in this meta-analysis (6 of 12 eligible studies were analyzed for TNF 238 G/A polymorphism and Type 1 DM (T1DM), 5 of 12 were analyzed for TNF 308 G/A polymorphism and DR in Type 2 DM (T2DM), and 3 of 12 were analyzed for TNF 308 G/A polymorphism and DN in T2DM). Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using fixed or random effects model. The I(2) statistics were used to evaluate between-study heterogeneity. Sensitivity analysis was also performed.


RESULTS
The results showed no evidence for significant association between TNF 238 G/A polymorphism and T1DM (for AA + GA versus GG: OR = 0.95, 95% CI = 0.48-1.88, p = 0.89), and also no association between TNF 308 G/A polymorphism and DR and DN risk in T2DM (for AA + GA versus GG: OR = 1.04, 95% CI = 0.87-1.25, p = 0.68; OR = 0.88, 95% CI = 0.71-1.08, p = 0.21; respectively). In addition, the similar results were obtained in the subgroup analysis based on the ethnicity.


CONCLUSIONS
In summary, results from this meta-analysis suggest that the TNF 238 G/A polymorphism was not associated with T1DM. No association between TNF 308 G/A polymorphism and DR and DN in T2DM was detected.
Department of Ophthalmology, Qilu Hospital of Shandong University , Jinan , China.
Nana
N
Meng
Yue
Y
Zhang
Hao
H
Li
Jinlan
J
Ma
Yi
Y
Qu
D000293:Adolescent; D000328:Adult; D003920:Diabetes Mellitus / Q000235:genetics*; D003928:Diabetic Nephropathies / Q000235:genetics*; D003930:Diabetic Retinopathy / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012307:Risk Factors; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
D014409:Tumor Necrosis Factor-alpha