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Whether the Adrenoceptor Beta 3 (ADRB3) gene rs4994 polymorphism could affect the individual risk of childhood and adolescent overweight/obesity remains controversial. This meta-analysis was performed to estimate the prevalence of this polymorphism in overweight/obesity, and test the potential association by summarizing existing evidence. Comprehensive literature search in PubMed, Web of Science, Cochrane Library, Wanfang, and CNKI databases was performed to identify eligible data sets. Finally, 16 studies involving 5,147 overweight/obese cases and 7,350 non-obese controls were included for further synthetic analyses. Odds ratio (OR) and its corresponding 95% confidence intervals (CIs) were statistically calculated. Totally, 69.9% of the included subjects came from East Asia. In the meta-analysis for overall population, statistically significant associations with increased risk of childhood and adolescent overweight/obesity were identified in allele model (OR 1.23, 95% CI 1.10-1.38), heterozygote model (OR 1.39, 95% CI 1.16-1.68), and dominant model (OR 1.31, 95% CI 1.12-1.54). Further stratified analysis according to geographical regions revealed that the statistical significance could only be detected in the East Asia subgroup in allele model, homozygote model, heterozygote model, and dominant model. In summary, our meta-analysis indicated that the ADRB3 rs4994 polymorphism could significantly increase the risk of childhood and adolescent overweight/obesity, especially for the East Asia's population.

Objective: As an important DNA repair gene, the xeroderma pigmentosum complementation group C (XPC) gene and its functional genetic variants' relationship with chemotherapy response has been extensively studied. To quantitatively elucidate the genetic impact of the XPC rs2228000 and rs2228001 polymorphisms on the response to platinum-based chemotherapy, the present meta-analysis was conducted. Materials and methods: A systematic literature search was performed in seven cyber databases until February 20, 2019, for all relevant studies that assessed the relationship between XPC polymorphisms and the response to platinum-based chemotherapy. Odds ratios (ORs) with a 95% confidence interval (95% CI) were measured to assess the strength of the association. R programs were developed to perform the statistical analyses, including calculations of pooled estimates, publication bias and sensitivity analyses, and heterogeneity interpretations. Results: A total of 1,615 patients from 10 studies for the rs2228001 polymorphism were winnowed for further statistical analysis. For the rs2228000 polymorphism, 858 samples from six datasets were included. However, this meta-analysis indicated no significant effect of these two XPC polymorphisms on the response to platinum-based chemotherapy. When stratified according to sample size, country or cancer type, no statistical significance for association was identified in all subgroups. Further sensitivity analysis and publication bias assessment ensured the reliability of the meta-analysis. Conclusions: The pooled estimates suggest that neither the rs2228000 polymorphism nor the rs2228001 polymorphism contributes to the genetic predisposition for an altered response to platinum-based chemotherapy. Considering the limitations of our present meta-analysis, more studies with large-scale cohorts and rigorous methods are needed to validate our results.

BACKGROUND The effect of the patatin-like phospholipase domain containing 3 gene (PNPLA3) I148M polymorphism on the risk and severity of paediatric and adolescent nonalcoholic fatty liver disease (NAFLD) remains inconclusive. OBJECTIVES We aimed to estimate the effect of this polymorphism not only on early-onset NAFLD risk and severity but also on metabolic syndromes susceptibility. METHODS A systematic literature search was performed to identify relevant datasets. The odds ratio of the dichotomic variables and the standardized mean difference of quantitative variables with corresponding 95% confidence intervals were calculated to assess the strength of the associations. RESULTS Twenty-seven studies comprising 10 070 subjects were eligible. The summary effect showed that this polymorphism increased susceptibility to NAFLD development. Furthermore, it also indicated that nonalcoholic steatohepatitis (NASH) was more frequently observed in G allele carriers among paediatric and adolescent NAFLD patients. Moreover, the meta-analysis suggested that the variant was significantly associated with elevated liver damage indexes, including serum alanine transaminase, aspartate transaminase, gamma-glutamyltransferase concentrations, and liver fat content. However, the summary estimates for insulin resistance, lipid metabolism, and adiposity showed no significant associations. CONCLUSIONS The PNPLA3 I148M polymorphism is associated with elevated early-onset NAFLD risk, severity, and liver damage but not with related metabolic syndromes.