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The aim of this study was to explore whether interleukin-6 (IL-6) gene (-174 G/C and -572 C/G) polymorphisms are associated with susceptibility to coronary artery disease (CAD) risk in Chinese population. All the statistical tests were performed using Stata version 11.0. Twelve articles involving 16 studies were included in this meta-analysis, covering a total of 2309 CAD cases and 2273 controls. For IL-6 gene -572 C/G polymorphism, the results showed evidence for significant association between IL-6 gene -572 C/G polymorphism and CAD risk (for G allele vs. C allele: OR=1.48, 95% CI=1.26-1.74, p<0.001; for G/G vs. C/C: OR=2.60, 95% CI=1.54-4.39, p<0.001; for G/G vs. G/C+C/C: OR=2.15, 95% CI=1.35-3.42, p=0.001; for G/G+G/C vs. C/C: OR=1.55, 95% CI=1.29-1.85, p<0.001). However, for IL-6 gene -174 G/C polymorphism, no significant association was found between this variation and CAD risk. In summary, our meta-analysis showed evidence that IL-6 gene -572 C/G polymorphism may be a risk factor for CAD susceptibility. For IL-6 gene -174 G/C polymorphism, no significant association was found between this variation and CAD risk., (Copyright © 2015 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Aims: Toll-like receptor 4 (TLR4) gene Asp299Gly and Thr399Ile polymorphisms have been reported to be associated with susceptibility to type 2 diabetes mellitus (T2DM) with inconsistent results. In an effort to clarify earlier inconclusive results, a meta-analysis evaluating the precise associations between TLR4 gene Asp299Gly and Thr399Ile polymorphisms and T2DM risk was performed., Methods: We searched the PubMed, Embase, Web of Science, CBMdisc, CNKI, and Google Scholar until July 17, 2014. Additionally, hand searching of the references of identified articles were performed. Original observational studies dealing with the associations between TLR4 gene Asp299Gly and Thr399Ile polymorphisms and T2DM risk were selected. Heterogeneity and publication bias were determined and the meta-analysis was performed by Review Manager 5.1.4 and Stata 11.0., Results: Seventeen articles involving 25 studies were included in the final meta-analysis, covering a total of 5963 T2DM cases and 9096 controls. For TLR4 gene Asp299Gly polymorphism, 17 studies were combined showing no evidence for association between TLR4 gene Asp299Gly polymorphism and T2DM risk. For TLR4 gene Thr399Ile polymorphism, eight studies were combined. There was also lack of evidence for significant association between TLR4 gene Thr399Ile polymorphism and T2DM risk. In addition, the similar results were obtained in the sensitivity analyses., Conclusions: The present meta-analysis indicates that TLR4 gene Asp299Gly and Thr399Ile polymorphisms are not associated with increased T2DM risk., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Background: Several studies have investigated whether the polymorphism in the apolipoprotein A5 (APOA5) is associated with type 2 diabetes mellitus (T2DM) risk. However, those studies have produced inconsistent results. The purpose of this study was to investigate whether the APOA5 -1131T/C polymorphism (rs662799) confers significant susceptibility to T2DM using a meta-analysis., Methods: PubMed, Embase, Web of Science, Cochrane database, CBMdisc, CNKI and Google Scholar were searched to get the genetic association studies. All statistical analyses were done with Stata 11.0., Results: A total of 19 studies included 4,767 T2DM cases and 10,370 controls (four studies involving 555 T2DM cases and 2958 controls were performed among Europeans and 15 studies involving 4212 T2DM cases and 7412 controls were performed among Asians) were combined showing significant association between the APOA5 -1131T/C polymorphism and T2DM risk (for C allele vs. T allele: OR = 1.28, 95% CI = 1.17-1.40, p<0.00001; for C/C vs. T/T: OR = 1.57, 95% CI = 1.35-1.83, p<0.00001; for C/C vs. T/C+T/T: OR = 1.36, 95% CI = 1.18-1.57, p<0.0001; for C/C+T/C vs. T/T: OR = 1.32, 95% CI = 1.16-1.51, p<0.0001). In the subgroup analysis by ethnicity, significant association was also found among Asians (for C allele vs. T allele: OR = 1.31, 95% CI = 1.22-1.40, p<0.00001; for C/C vs. T/T: OR = 1.61, 95% CI = 1.38-1.88, p<0.00001; for C/C vs. T/C+T/T: OR = 1.39, 95% CI = 1.20-1.61, p<0.0001; for C/C+T/C vs. T/T: OR = 1.42, 95% CI = 1.25-1.62, p<0.00001). However, no significant association was found between the APOA5 -1131T/C polymorphism and T2DM risk among Europeans., Conclusions: The present meta-analysis suggests that the APOA5 -1131T/C polymorphism is associated with an increased T2DM risk in Asian population.

Several epidemiological studies have assessed the associations of interleukin (IL) gene polymorphisms with acute pancreatitis (AP) in different populations. However, the results were inconclusive. Therefore, we performed the present study to comprehensively evaluate the associations of IL gene polymorphisms and susceptibility to AP. Systematic searches of the PubMed, Web of Science, Embase, CNKI, CBMdisc and Google Scholar until February 27, 2013, as well as hand searching of the references of identified articles were performed. Data were extracted using standardized forms and odds ratios (ORs) with 95 % confidence intervals (CIs) were used to assess the strength of associations. All statistical analyses were performed using Stata 11.0. Ten studies were included in our final combined analysis, covering a total of 1,220 AP cases and 1,351 controls. The results showed evidence for significant association between IL-8 -251 T/A (rs4073) polymorphism and AP risk, suggesting that IL-8 -251 A allele was associated with an increased risk of AP (for A allele vs. T allele: OR = 1.36, 95 % CI 1.05-1.76, p = 0.02; for A/A vs. T/T: OR = 2.28, 95 % CI 1.08-4.81, p = 0.03; for A/A+T/A vs. T/T: OR = 1.40, 95 % CI 1.11-1.77, p = 0.005). However, there were no significant associations between IL-1β (IL-1β +3954 C/T (rs1143634) and IL-1β -511 C/T (rs16944)), IL-6 (IL-6 -174 G/C (rs1800795) and IL-6 -634 C/G (rs1800796)) and IL-10 (IL-10 -1082 A/G (rs1800896), IL-10 -819 C/T (rs1800871) and IL-10 -592 C/A (rs1800872)) gene polymorphisms and AP risk. In summary, the current study suggests that the IL-8 -251 T/A polymorphism is associated with an increased risk of AP. In addition, there were no significant associations between IL-1β, IL-6 and IL-10 gene polymorphisms and AP risk.

Epidemiological studies have evaluated the association between interleukin-6 (IL-6) gene -174 G/C polymorphism and type 1 diabetes mellitus (T1DM) risk, but results of different studies have been inconsistent. The present meta-analysis was therefore designed to clarify these controversies. PubMed, Embase and Web of Science were searched from the first available year to March 25, 2012, as well as hand searching of the references of identified articles were performed. All studies investigating the association between IL-6 gene -174 G/C polymorphism and T1DM risk were included. Data analyses were carried out by Review Manager 5.1.2 and Stata 11.0. Seven studies were included in the final meta-analysis, covering a total of 9697 T1DM cases and 8455 controls. The results showed no evidence for significant association between IL-6 gene -174 G/C polymorphism and T1DM risk (for C/C+C/G vs. G/G: OR=1.30, 95% CI=0.84-2.00, p=0.24; for C/C vs. C/G+G/G: OR=1.10, 95% CI=0.75-1.60, p=0.63; for C/C vs. G/G: OR=1.34, 95% CI=0.75-2.42, p=0.33; for C allele vs. G allele: OR=1.16, 95% CI=0.88-1.53, p=0.30). In addition, the similar results were obtained in the subgroup analysis based on ethnicity. In summary, the present meta-analysis suggests that IL-6 gene -174 G/C polymorphism is not associated with T1DM risk. However, due to the small sample size in most of the included studies and the selection bias existed in some studies, the results should be interpreted with caution., (Copyright © 2012 Elsevier B.V. All rights reserved.)

It remains controversial regarding the association between interleukin-8 (IL-8) gene -251 T/A polymorphism and peptic ulcer disease (PUD) risk. Thus, a large-scale meta-analysis evaluating the precise association between this gene variant and PUD risk is required. We searched the PubMed, Embase, Web of Science, and Google Scholar until April 25, 2012. Additionally, hand searching of the references of identified articles were performed. All the statistical tests were performed using Stata 11.0. A total of eight studies (3105 subjects) were included in this meta-analysis. Overall, no significant association was found between IL-8 gene -251 T/A polymorphism and PUD risk (for A allele vs. T allele: OR = 1.17, 95% CI = 0.97-1.41, p = 0.094; for A/A vs. T/T: OR = 1.33, 95% CI = 0.94-1.90, p = 0.108; for A/A vs. A/T+T/T: OR = 1.22, 95% CI =0.97-1.52, p = 0.083; for A/A+A/T vs. T/T: OR = 1.26, 95% CI = 0.95-1.67, p = 0.113). However, in the subgroup analyses by ethnicity, H. pylori infection and the subtype of PUD, significant associations were found between IL-8 gene -251 T/A polymorphism and PUD risk in Asians, H. pylori+, duodenal ulcer disease (DUD) and gastric ulcer disease (GUD), respectively. In summary, the present meta-analysis suggests that IL-8 gene -251 T/A polymorphism is associated with increased PUD risk among Asians, and especially for the subgroups of H. pylori+, DUD and GUD., (Copyright © 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Background: Epidemiological studies have evaluated the association between tumor necrosis factor α (TNF-α) single nucleotide polymorphisms (SNPs) and duodenal ulcer (DU), but the results remain inconclusive. The aim of this study was to perform a meta-analysis to investigate a more authentic association between TNF-α SNPs and DU., Methods: We performed the meta-analysis by searching PubMed, Embase, and Web of Science databases from the first available year to Sep. 5, 2012. Additionally, checking reference lists from identified articles, reviews, and the abstracts presented at related scientific societies meetings were also performed. All case-control studies investigating the association between TNF-α SNPs and DU risk were included. The association was assessed by odds ratio (OR) with 95% confidence interval (CI). Publication bias was analyzed by Begg's funnel plot and Egger's regression test., Results: A total of sixteen studies reporting TNF-α -308G/A, -1031T/C, -863C/A, -857C/T, and -238G/A polymorphism were included in our final meta-analysis. There was no statistically significant association between -308G/A polymorphism and DU in the overall study population, as well as subgroup analyses by ethnicity, study design, and H. pylori status. As for -1031T/C, -863C/A, -857C/T, and -238G/A, results of our meta-analyses showed no statistical evidence of significant association. Power calculation on the combined sample size showed that the statistical powers were all lower than 80% for all the meta-analyses., Conclusions: The data suggests that there is no statistical evidence of significant association between the studied TNF-α SNPs and DU. However, this conclusion should be interpreted with caution as low statistical powers were revealed by power calculations. In future, larger sample-size studies with homogeneous DU patients and well-matched controls are required.

Background: Epidemiologic studies have evaluated the association between tumor necrosis factor-alpha (TNF-α) gene -308A/G polymorphism and the risk of acute pancreatitis (AP), but the results are inconsistent. In order to derive a more precise estimation of the associations, a meta-analysis was performed., Materials and Methods: Systematic searches of electronic databases PubMed, Embase, and Web of Science, as well as hand searching of the references of identified articles, were performed. All case-control studies investigating the association between TNF-α gene -308A/G polymorphism and AP risk were included. The association was assessed by odds ratio (OR) with 95% confidence intervals (CIs). Publication bias was analyzed by Begg's funnel plot and Egger's regression test., Results: The initial search revealed 818 potentially eligible studies. Having read the title, abstract, or full text, we included six relevant studies in the final meta-analysis, which contained 1,006 AP cases and 782 controls. Overall, no significant association was found between TNF-α gene -308A/G polymorphism and AP risk when all studies were pooled into the meta-analysis (for A/A+A/G versus G/G: OR = 1.03, 95% CI = 0.83-1.28, P = 0.79; for A/A versus A/G+G/G: OR = 0.97, 95% CI = 0.65-1.45, P = 0.87; for A/A versus G/G: OR = 1.23, 95% CI = 0.79-1.91, P = 0.37; for A allele versus G allele: OR = 0.99, 95% CI = 0.83-1.18, P = 0.90). In addition, the similar results were obtained in the subgroup analysis based on the ethnicity and subtype of AP., Conclusions: The present meta-analysis reveals that the TNF-α gene -308A/G polymorphism is not associated with AP risk. However, due to the small number of subjects included in analysis and the selection bias in some studies, the results should be interpreted with caution., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Epidemiological studies have evaluated the association between IL-1β -511 C/T polymorphism and duodenal ulcer (DU) risk. However, the results remain conflicting. The aim of this study was to perform a meta-analysis to investigate a more authentic association between IL-1β -511 C/T polymorphism and DU. Systematic searches of electronic databases Embase, PubMed and Web of Science as well as hand searching of the references of identified articles and the meeting abstracts were performed. Study selection, data abstraction and study quality evaluation were independently conducted in duplicate. Statistical analyses were performed using software Stata 11.0. The pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were performed. Publication bias was tested by Begg's funnel plot and Egger's regression test. A total of 14 studies including 1887 cases and 2780 controls were included in our final meta-analysis. There was no evidence of significant association between IL-1β -511 C/T polymorphism and DU (for T allele vs. C allele: OR=0.93, 95% CI=0.82-1.06; for T/T vs. C/C: OR=0.83, 95% CI=0.64-1.08; for dominant model: OR=0.93, 95% CI=0.80-1.07; and for recessive model: OR=0.87, 95% CI=0.69-1.11). Significant association was found in all genetic models for the PB subgroup and sensitivity analyses. In conclusion, our meta-analysis suggests that there was no evidence of a significant association between IL-1β -511 C/T polymorphism and DU with or without Helicobacter pylori infection, whereas a significant association was found by sensitivity analyses which showed a protective effect of the T allele against DU risk., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Increasing evidence suggests that interleukin-10 (IL-10) gene -592 C/A polymorphism may be associated with an increased risk of type 2 diabetes mellitus (T2DM). To provide a quantitative assessment of the association between this variant and risk of T2DM, we performed this meta-analysis. Systematic searches of electronic databases PubMed, Embase, Web of Science, CBMdisc and CNKI, as well as hand searching of the references of identified articles were performed. A total of 2698 T2DM cases and 2622 controls in seven case-control studies were included in this meta-analysis. The results showed no evidence for significant association between IL-10 gene -592 C/A polymorphism and T2DM risk (for A allele vs. C allele: OR=0.94, 95% CI=0.69-1.29, p=0.69; for A/A vs. C/C: OR=0.88, 95% CI=0.39-1.98, p=0.75; for A/A vs. A/C+C/C: OR=1.04, 95% CI=0.59-1.82, p=0.89; for A/A+A/C vs. C/C: OR=1.11, 95% CI=0.73-1.69, p=0.61). In addition, the similar results were obtained in the subgroup analysis based on the ethnicity. In summary, results from this meta-analysis suggest that the IL-10 gene -592 C/A polymorphism is not associated with T2DM risk., (Copyright © 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)