ASD) has been recently debated due to emerging findings on the importance of shared environmental influences. However, two recent twin studies do not support this and instead re‐affirm strong genetic effects on the liability to ASD, a finding consistent with previous reports. This study conducts a systematic review and meta‐analysis of all twin studies of ASD published to date and explores the etiology along the continuum of a quantitative measure of ASD.The etiology of Autism Spectrum Disorder  were almost perfect at .98 . The dizygotic (DZ) correlation, however, was .53 (95% CI .44–.60) when ASD prevalence rate was set at 5% (in line with the Broad Phenotype of ASD) and increased to .67 (95% CI .61–.72) when applying a prevalence rate of 1%. The meta‐analytic heritability estimates were substantial: 64–91%. Shared environmental effects became significant as the prevalence rate decreased from 5–1%: 07–35%. The DF analyses show that for the most part, there is no departure from linearity in heritability.The meta‐analysis correlations for monozygotic twins  shared environmental effects become significant as a function of lower prevalence rate; (c) previously reported significant shared environmental influences are likely a statistical artefact of overinclusion of concordant DZ twins.We demonstrate that: (a)  Autism is known as a severe pervasive neurodevelopmental disorder with poor prognosis. The disorder is characterized by difficulties in social interaction, verbal and nonverbal communication and repetitive behaviours, and is more prevalent in males ] have been reviewed and summarized most recently by Ronald & Hoekstra  extremes analysis on quantitative measures of ASD, Frazier et al.  showed tThe aims of this study are fivefold: (a) to reconsider the inconsistent findings, especially with respect to the evidence for shared environmental influences on ASD; (b) to independently estimate twin correlations and heritability estimates for each study while correcting for selection and ascertainment strategy ; (c) to conduct a meta‐analysis of the published studies using appropriate corrections for selection and ascertainment strategy for each individual study; (d) to study the effects of assumed prevalence rates (fixed thresholds) son twin correlations and heritability estimates in each individual study and on the combined sample; (e) to examine group heritabilities along the distribution of a quantitative ASD measure.To summarize, in this paper we report results of a quantitative meta‐analysis of the combined data of published twin studies of ASD to date. Many primary twin studies on low prevalence disorders such as ASD are based on ascertained samples of relatively small size. The benefit of the present analysis is not only to produce the best unbiased estimates by applying appropriate ascertainment and selection correction methods but also to increase statistical power to detect effects of small size. In addition to the meta‐analyses, we also explored the etiology along the continuusm of a quantitative ASD measure . The differences in MZ and DZ correlations provide information on the relative importance of genetic and environmental variance as specified in a standard biometrical genetics model . This is equivalent to multiplying the likelihood function by 1/the probability density of the remaining cells: 1/1−Ã, which is accomplished by including a weight model.For nonrandomly selected samples, ascertainment corrections adjust the bivariate normal distribution for the unobserved response categories , provided that the threshold is known. This is achieved by dividing the RPA samples likelihood function by the probability density of the remaining cells  Ascertainment the correction factor used to multiply the likelihood function eq  by is:  is below threshold for the disorder (unaffected), i.e. individual which come to the attention of the study (probands) must be affected.Under Single Ascertainment the correction factor used to multiply the likelihood function eq  by is:  and ‘doubly’ (D) ascertained concordant pairs) is dependent on The likelihood of the doubly ascertained concordant pairs is corrected by weight: π for IA are either provided by the studies or computed by utilising information available in the publications.Estimates of π and the threshold z‐values corresponding to the reported prevalences in the individual studies. When not provided, we used a prevalence of 5% [fixed z‐value of 1.65] for ASD .In contrast to variance decomposition analysis used in the classical twin study, DF extremes analysis  are shown in Figure rMZ = 0.98 (95% CI 0.97–0.99), rDZ = 0.62 (95% CI 0.55–0.68). In the second meta‐analysis, the thresholds of study 6 and 9 were fixed to a 5% prevalence  which is more in line with the Broad Phenotype definition: rMZ = 0.98 (95% CI 0.96–0.99), rDZ = 0.52 (95% CI 0.44–0.60). Next, only studies conducted after 1995, signifying the awareness of the Broad Phenotype definition, were included. In that meta‐analysis, we fixed thresholds as reported in each study but estimated the threshold for study 8: rMZ = 0.98 (95% CI 0.96–0.99), rDZ = 0.62 (95% CI 0.55–0.68). Finally, again considering the studies conducted after 1995, we fixed all prevalences to 5%, 3% and 1%, respectively, to test the range of values reported for ASD and the Broad Phenotype in the literature. In effect, we found that as the prevalence rate decreased from 5% to 3% to 1%, the DZ correlations increased.The first was on all selected studies using fixed thresholds based on prevalences as reported in each study (see Data S1), aside from study 8 for which the threshold is always estimated: The A, C and E point estimates (corrected for incomplete ascertainment and selection) can be found in Table S2. The forest plot , with a significant proportion of shared environmental effects: 25% 95% CI 0.12–0.37). In the second meta‐analysis, when the thresholds of study 6 and 9 were fixed to 5% prevalence, the heritability increases to 93% (95% CI 0.77–0.99) and C becomes nonsignificant. A detailed investigation of studies conducted after 1995, in which the Broad Phenotype definition for ASD was included, applying thresholds as reported in each study gave estimates similar to when all studies were considered. However, when we subsequently fixed all thresholds to either 5%, 3% or 1%, we saw an increase in the proportion of C  compared to .67 (.61/.72), meaning that C was significantly different (61% vs. 35%). Overall, however, these results did not change the conclusion that the DZ correlation (and the power to detect C) increases as a function of increasing the fixed threshold in the liability model.Figure Using a quantitative meta‐analytic approach, we estimated the heritability of ASD using studies of twins with a  diagnosis of autism spectrum disorder. Applying appropriate ascertainment corrections and maximum likelihood estimation, our study produced tetrachoric twin correlations and heritability estimates for all studies published to date, inclusive of studies that previously only reported proband‐wise concordant rates. The meta‐analytic heritability estimates ranged between 64% and 91% (despite diagnostic heterogeneity) and are in line with previous reports  samples is fixing the threshold in the model to the prevalence rate of the disorder in the general population. The different diagnostic outcomes across ASD studies prove problematic to derive the correct overall prevalence in meta‐analysis. When looking at the individual studies as well as the meta‐analysis results, it is apparent that detecting significant heritable variance is quite robust, but detecting significant C effects depends on the assumed prevalence of the disorder. Effectively, pushing the threshold to higher values  will not affect the MZ twin correlations as much since they are already at the top of their statistical bound . However, the DZ correlations will increase relative to the MZ correlations, consistent with increasing the effect of shared environment. Given the importance of this effect, fitting multiple‐threshold models including a Broader Phenotype as a meaningful subcategory with a lower (fixed) threshold on the spectrum to ASD . The only way to determine whether ASD as a disorder fits the characteristics of a polygenetic trait is via molecular genetic studies. There is evidence for the contribution of both common variants and rare mutations (Gaugler et al., Using an appropriate meta‐analytic statistical approach we demonstrated that the etiology of ASD in a combined sample is more consistent with strong genetic influences. Second, we can reject the claim that there is a strong shared environmental effect on autism spectrum disorders accounting for the majority of variance and alert to the danger of placing too much weight on findings from a single study, such as Hallmayer et al. .do not exclude the possibility that environmental, or at least nongenetic, effects influence ASD. But unless a suitably powered and well‐designed new study comes forward, this claim should be put to one side for now.At the same time, we Two recent studies point toward importance of shared environments in ASD.This effect is potentially a statistical artefact due to overinclusion of concordant DZ twins.Differential prevalence assumptions can alter heritability estimates.Clinically recognised Broad Phenotype ought to be recognised in statistical modelling by fitting multiple thresholds to reflect the quantitative genetic risk for ASD.Appendix S1. The classical twin method.Click here for additional data file.Appendix S2. Example of Meta‐Analysis Mx script.Click here for additional data file.Appendix S3. Meta‐Analysis Data.Click here for additional data file.Table S1. Maximum likelihood estimates of the MZ and DZ twin correlations.Click here for additional data file.Table S2. Maximum likelihood estimates of the genetic and environmental variance components.Click here for additional data file.


To better clinical outcomes, open reduction and internal fixations (ORIFs) have been commonly performed in the case of closed displaced intra-articular calcaneal fractures (CDICFs). Nonetheless, postoperative wound complications remain a significant problem. Therefore, the aim of our study is to summarise relevant evidence investigating the risk factors for postoperative wound complications of CDICFs following ORIFs.A meta-analysis was conducted on relevant clinical studies to identify the risk factors for wound complications of CDICFs after ORIFs. Electronic databases were searched for all relevant studies up to October 2014. The Newcastle-Ottawa scale was used to evaluate the methodological quality, and study-specific odds ratios (ORs) were pooled using the fixed-effects model or random-effects model. Sensitivity analysis and meta-regression analysis was performed to evaluate the heterogeneity.p < 0.01), no drainage , fracture severity  and bone graft  were the risk factors for wound complications of CDICFs after ORIFs. A trend of more wound complications in patients with a history of smoking was detected. However, female patients, ORIFs performed within 14 days of injury, smoking, hypertension and drinking did not significantly increase the risk of wound complications (p > 0.05).Ten observational studies involving 1559 patients with 1651 fractures were included in this meta-analysis. The results showed that diabetes  contains supplementary material, which is available to authorized users. Calcaneal fractures are one of the most common fractures of the hind foot . They geThere has been a matter of conflict on the treatment of CDICFs. Open reduction and internal fixation (ORIF) would restore calcaneal height, the mechanical axis of the hindfoot and subtalar joint , which tTherefore, it is important to reduce the rate of wound complications when CDICFs were treated with ORIFs. To identify the risk factors for wound complications, several studies have been published -23, but This meta-analysis was performed according to the preferred reporting items for systematic reviews and meta-analyses guidelines (the PRISMA statement) , which were published up to October 10, 2014. The following keywords or corresponding Medical Subject Headings (MeSH) were used: “fractures of the os calcis”, “calcaneal fractures”, “fractures of calcaneum”, “fractures of calcaneus”, “fractures of hindfoot”, “complications”, “infection”, “debridement”, “oozing”. Full details of search strategy are included in Additional files We identified studies according to the following inclusion criteria: (1) participants: human adults (minimum of 18 years of age) with CDICFs; (2) intervention: ORIF; (3) comparison: patients with potential risk factors versus patients without potential risk factors resulting in higher or lower rate of wound complications; (4) sufficient data were available for estimating an odds ratio (OR) with confidence interval (CI).The following criteria were used for exclusion: (1) minimally invasive reduction and fixation; (2) CDICFs with a primary arthrodesis; (3) animal studies and cadaver studies.Three authors  extracted relevant data independently, including the first author’s name, study region, study design, average age of participants, the number of case group (patients who experienced wound complications) and control group (patients who did not experience wound complications), operative approach, type of closure (one-layered or double-layered), duration of follow-up, potential risk factor for wound complications, and the number of major complications . In addition, we also tried to contact the authors of the eligible studies to ask for relevant original data for this meta-analysis.In terms of the Newcastle-Ottawa Quality Assessment Scale , the metI2. I2 > 50% was considered as high statistical heterogeneity [p > 0.1 and I2 < 50%, the fixed-effects model was used; otherwise, we used the random-effects model. I2 > 50% was considered as high heterogeneity. Then, sensitivity analysis was conducted by omitting one study at one time and examining the influence of each individual study on the overall OR. To identify the origin of the heterogeneity among studies, we conducted meta-regression analysis based on methodological quality or clinical diversity . Egger’s test and Begg’s test were performed to assess the publication bias. For all statistical analyses except heterogeneity and publication bias, a value of p < 0.05 was regarded as statistically significant, and all tests were two-sided.The statistical analyses were performed with Stata 12.0 software . The ORs with corresponding 95% CIs were considered as the effect estimates for all included studies. Study-specific ORs were pooled using fixed-effects model or random-effects models. The statistical heterogeneity was assessed with the Q-test and ogeneity . If p > The process of study selection is presented in Figure The characteristics of the 10 included studies are presented in Table Table p = 0.007), diabetes , no drainage  and fracture severity  were the significant risk factors for postoperative wound complications of CDICFs after ORIFs. However, female patients, ORIFs performed within 14 days of injury, smoking . In addition, ORIFs performed within 14 days of injury and smoking did not significantly affect the rate of major wound complications (p > 0.05) . For smoking, sensitivity analysis was performed. The results demonstrated that the association was similar when one study was omitted at one time .High heterogeneity was detected among studies evaluating as potential risk factors for smoking, female patients, and drinking  and Egger’s test , which was consistent with previous results ,22,27. B, which wOur results showed that there was no significant difference in risk of postoperative wound complications between patients with or without a history of smoking, but a trend of more wound complications in patients with smoking history was observed (26.4% vs. 17.5%). Consistent results were observed in several studies ,21,32,33Diabetes was the strongest risk factor for wound complications (OR = 9.97). Patients with diabetes had a 9.97-times greater risk of wound complications when compared with patients without diabetes. It has been demonstrated that diabetes could impede wound healing due to microvascular abnormalities .As for female patients, drinking and hypertension, the results showed that they were not associated with the rate of wound complications. Similar results were reported in previous studies ,22. In oWe found that bone grafting would increase the risk of wound complications (OR = 1.74). Similarly, a systematic review revealed that the infection rate in the bone graft group was higher than that in non-graft group (8.3% vs. 6.3%) . Other sOur results showed that conditions with no drainage increased the risk of postoperative wound complications (OR = 5.68). A closed suction drain reduces the formation of haematomas thereby decreasing the likelihood of prolonged oozing from the wound, delayed wound healing or infection of the wound . EvidencFor surgical timing, there is no difference between whether ORIFs were performed within 14 days of the injuries or later in our study. The correlation between surgical timing and wound complications remains an unsettled issue. Surgeries should be carried out after the condition of soft tissue improves . Wu et aIn this study, several risk factors were not combined due to inconsistent data forms or insufficient data. Longer operative time , prolongThis study has several strengths. Firstly, to the best of our knowledge, this study is the first meta-analysis that quantitatively summarizes risk factors for wound complications of CDICFs after ORIFs. Secondly, the pooled outcomes are reliable due to our comprehensive data search, rigorous evaluation of methodological quality and the heterogeneity measure. Moreover, most included studies came from level-one trauma centers.It is undeniable that there are some limitations in this study. First, all the included studies were retrospective cohort studies or case–control studies involving unavoidable recall and interviewer biases. Second, significant heterogeneity was detected in some pooled outcomes. However, after sensitivity analysis, meta-regression analysis and excluded publication bias, the outcomes are reliable. In addition, unadjusted confounding factors, such as the application of antibiotics, the experience of surgeons and the compliance of patients, which could influence the rate of wound complications, were not fully accounted for in several studies.Based on available evidences, bone graft, diabetes, no drainage and fracture severity were identified as risk factors for wound complications of CDICFs after ORIFs. Meanwhile, a smoking-cessation should be adopted before ORIFs. Prior to surgical treatment of CDICFs, patients who have the risk factors identified in this study should be counselled concerning the possible complications that might arise after ORIFs. Meanwhile, clinicians should consider the relevant risk factors to choose a better therapeutic strategy. In addition, future well-designed studies should be conducted to confirm these findings.


Observational studies of thyroid function and dementia have reported conflicting results. We reviewed cohort and case-control studies from MEDLINE, EMBASE, Web of Science and the Cochrane Library that focused on the association between serum thyroxine, thyrotropin and dementia. A total of 24,952 participants from three case-control and eight cohort studies were included. The relationships between dementia and the per standard deviation (SD) increment of free thyroxine (FT4) (random relative ratio (RR) = 1.08, 95% confidence interval (CI) 1.00–1.17) and thyroid-stimulating hormone (TSH)  were well established. TSH levels in the low category were associated with an increased risk of dementia . However, the positive association was confined to TSH levels below the normal range , not those in the lower tertile of the normal range . Additionally, dementia was not significantly associated with high TSH levels . Furthermore, there was no positive association between dementia and the low or high categories of TSH in men. Thus, individuals with higher FT4 levels or those with TSH levels below the normal range have an increased risk of dementia. Dementia is a clinical syndrome characterized by a cluster of symptoms and signs that results in complex cognitive decline; it has emerged as one of the greatest health threats during old age and has substantial socioeconomic costs. Alzheimer’s disease (AD), which is the most common type of dementia, constitutes 50–70% of cases3et al.71510Thyroid hormone (TH) regulates metabolic processes that are essential for normal growth and development as well as neurocognitive function after development78911et al.434478910151646et al.15The search strategy identified 1791 citations for evaluation. A manual review of the study references yielded one additional study. After carefully scanning the titles and abstracts, 39 articles that were potentially eligible for inclusion were retrieved. After reading the full texts, 28 articles were excluded for the following reasons: nine studies were not cohort or case-control studies18192021222324251314172728293031323334353738392) of 48.5% (P = 0.120) using the random effect model     increment of FT4 was associated with an increased risk of dementia (relative ratio (RR) = 1.08, 95% confidence interval (CI) 1.00–1.17) with a heterogeneity (Ict model . Five st= 0.744) . Moreove= 0.578) . Further= 0.291) .2 = 0%, P = 0.440), while cohort studies did not show this association. For data types regarding TSH levels, there were two low categories: the lower tertile of TSH levels within the normal range and TSH levels below the normal range. Likewise, there were two high categories: the upper tertile of TSH levels within the normal range and TSH levels above the normal range. Subgroup analyses revealed that only TSH levels below the normal range  or those in the two high categories, were associated with dementia. Three studies evaluated the relationship between TSH and dementia in men; meta-analyses of the low and high categories of TSH levels showed no association with dementia in men  and data on TSH levels and gender. Stratified analyses were not performed using the per SD increment of FT4 and TSH levels model because all the included studies were cohort studies. When low and middle categories of TSH levels were compared, the results of analyses stratified by study design were consistent with the overall trend. Additionally, case-control studies showed a positive association between high TSH levels and dementia . Stratified analysis by case-control study showed high TSH levels had a protective tendency for dementia, while the analysis by cohort study showed no association between high TSH levels and dementia, indicating that this association still needs to be investigated. Our observation was also consistent with the two placebo-controlled, double-blind randomized clinical trials of T4 medication administered for 1 year49Furthermore, a differential risk by gender in the TSH analyses existed in several studies936Remarkably, some scholars have suggested that low TSH and high FT4 levels may be biomarkers of age, and both parameters are associated with other diseases that occur in patients of advanced age, including dementia. In addition, low TSH levels might be a consequence of AD-related neurodegeneration, which could reduce the secretion of TRH by the hypothalamus or decrease the responsiveness of the pituitary gland to TRHOur meta-analysis had some limitations. First, although bias may exist due to the observational nature of the included studies and different data collection methods (prospective or retrospective), the relatively large combined sample size and good quality of the included studies potentially strengthen the power of the analysis. Second, the methods used to detect thyroid function and covariates differed among the studies. No specific reference range of hormone levels was provided. Moreover, three RRs in the TSH model were calculated manually based on the available data in the respective studies, whereas other data were extracted from the most adjusted regression models. A more precise analysis should be conducted when individual data are available. Third, a subgroup analysis by age was not performed because of insufficient data. The incidence of AD differs with age, and the prevalence doubles every five years after the age of 60In conclusion, this report is the first meta-analysis illustrating the contribution of TSH and FT4 to dementia. Based on 24,952 participants including 1526 patients with dementia, an increased risk of dementia in individuals with higher serum FT4 levels and in those with TSH levels below the normal range was found. The present study implied T4 replacement therapy may be administered cautiously, as no specific relationship was shown between high TSH levels and dementia. Moreover, individuals receiving T4 replacement therapy may develop a low or even a suppressed TSH levelhttp://www.prismastatement.org/statement.htm) and the Meta-analysis of Observational Studies in Epidemiology group (MOOSE)This meta-analysis was conducted according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2009 Checklist ”, “thyrotropin (TSH)”, “triiodothyronine (T3)”, “hyperthyroidism”, “hypothyroidism”, “euthyroidism”, “subclinical hyperthyroidism”, “subclinical hypothyroidism”, “thyroid dysfunction or disorders”, “dementia”, “Alzheimer’s disease (AD)”, “cognitive decline or impairment or defect”, “mild cognitive impairment (MCI)” and “cohort or case-control or longitudinal or follow-up”. Studies were initially included in the detailed assessment if they met the following criteria: 1) sufficient information on the study population; 2) cohort or case-control studies; 3) clear criteria for the outcome (dementia or AD) diagnosed according to internationally accepted criteria for dementia DSM-III-R and AD , by a muTwo investigators (Wu Y and Pei Y) independently extracted the data from the eligible studies with a common form. The outcome was dementia or AD. The following data were extracted: first author, publication year, study type, country or race, study size, age of participants, gender distribution, duration of follow-up, covariates, and results . GeneralThe Newcastle Ottawa Scale, a measure of the quality of observational studies, was used to assess the quality of the selected studies. This scale consists of three domains, including the selection of cases, comparability of populations, and ascertainment of exposure. Scores of 0–3, 4–6, and 7–9 indicate low, moderate, and high quality, respectively. Two investigators independently performed the quality assessment, and disagreements were resolved by discussion.2 statistic: I2 < 25%, low; between 25 and 50%, moderate; and >50%, highDichotomous data were calculated as the OR and 95% CI. In the meta-analysis, the RRs were used for risk estimates. ORs and HRs were also treated as RRs. Heterogeneity between studies was assessed using the IHow to cite this article: Wu, Y. et al. Higher FT4 or TSH below the normal range are associated with increased risk of dementia: a meta-analysis of 11 studies. Sci. Rep.6, 31975; doi: 10.1038/srep31975 (2016).


Aim. The purpose of this study is to determine the association between eotaxin 426 C/T, −384 A/G, 67 G/A, eNOS −786 T/C, 4 a/b, and MMP-13 rs640198 G/T and prognosis of patients with known CAD. Methods. From total of 1161 patients referred to coronary angiography, 532 patients with angiographically confirmed CAD were selected. Their long-term outcome was followed up using hospital database. Subsequent events were assessed in this study: death or combined endpoint-myocardial infarction, unstable angina pectoris, revascularization, heart failure hospitalization, and cardioverter-defibrillator implantation. Results. The multivariate Cox regression model identified age, smoking, and 3-vessel disease as significant predictors of all-cause death. Further analysis showed that eotaxin 67 G/A (GA + AA versus GG) and eotaxin −384 A/G (GG versus GA + AA) were significant independent prognostic factors when added into the model: HR (95% CI) 2.81 (1.35–5.85), p = 0.006; HR (95% CI) 2.63 (1.19–5.83), p = 0.017; eotaxin −384 A/G was significantly associated with the event-free survival, but it did not provide the prognostic information above the effect of two- or three-vessel disease. Conclusion. The A allele in eotaxin 67 G/A polymorphism is associated with worse survival in CAD patients. Cardiovascular diseases, particularly coronary artery disease (CAD), are the leading cause of mortality in developed countries. The aetiology of CAD is multifactorial and various well-known risk factors have been described in previous decades. Association of CAD prevalence and deoxyribonucleic acid (DNA) polymorphisms in human genes has been extensively studied , 2, but Matrix metalloproteinases are zinc-dependent endopeptidases cleaving proteins of extracellular matrix . Matrix-p = 0.037). Other functionally relevant polymorphisms were identified in the promoter of the gene, as −384 A/G and −426 C/T [Eotaxin (CCL11) is a chemokine with pleiotropic proinflammatory effects produced by several cellular types present in atherosclerotic lesion . Studies−426 C/T , which h−426 C/T , 26.Endothelial nitric oxide synthase (eNOS) is an enzyme that constitutively produces nitric oxide from L-arginine, mediating vasodilation and having other beneficial effects on vessel wall . The ratThe aim of our study is to assess the relationship between polymorphisms in eotaxin gene , MMP- 13 gene (rs640198), and endothelial NO-synthase (eNOS) gene (−786 C/T and 4 a/b) and a long-term outcome in Caucasian patients initially referred to coronary angiography.μmol/L), smooth coronary arteries or insignificant atherosclerosis, or life expectancy below 1 year. All patients gave their informed consent and study was approved by the institutional ethic committee. The personal and family history were obtained and all patients underwent physical examination, electrocardiography, haematological and biochemical blood tests, and coronary angiography. Coronary artery disease was defined as ≥50% stenosis of at least one coronary artery. Blood samples for DNA analysis from peripheral blood leucocytes were also taken. The selection of DNA polymorphism, analyses, results, and impact on incidence and severity of CAD were described in our previous publications [The study comprised of 532 subjects suffering of CAD that were recruited from the total number of 1161 consecutive patients referred to coronary angiography after applying the following exclusion criteria: known malignancy, advanced renal dysfunction , unstable angina pectoris, necessity of myocardial revascularization (either percutaneous or coronary artery bypass graft), hospitalization for heart failure, and cardioverter/defibrillator (ICD) implantation. Patients who were not under clinical observation in our hospital, patients without angiographically confirmed significant CAD, or those with unsuccessful DNA analysis were excluded from the study.p value 0.05 was used as a cut-off for an inclusion of variable in the Cox regression analysis. Hardy-Weinberg equilibrium was calculated for each polymorphism using χ2 test. Nongenetic variables included in the model were the following: age on admission, sex, presence of acute coronary syndrome, MI in personal history, ejection fraction, number of diseased vessels, obesity, hypertension, hyperlipidaemia, diabetes mellitus, concomitant presence of cardiomyopathy, significant valvular disease, and smoking status. Two endpoints were observed: all-cause death and cardiac endpoint consisting of MI, unstable angina, coronary revascularization, and rehospitalization for heart failure. Supposing unknown dominance of alleles, three modes of gene expressions were used: dominant, where minor allele carriers were compared with major allele homozygotes; recessive, where major allele carriers were compared with minor allele homozygotes; and additive, gene dose-based model, where the values 0, 1, and 2 were attributed to major allele homozygote, heterozygote, and minor allele homozygote. Stepwise construction of a Cox regression model with p value to include 0.05 and p value to remove 0.051 was finally employed to determine all significant independent factors  contributing to patients' survival or the incidence of cardiac event. STATISTICA software  was used for statistical analysis. MIDAS software version 1.0 [p values ≤ 0.05 were considered to be statistically significant.Multivariate Cox regression model was used for estimating the contribution of genetic polymorphisms and other risk factors to survival. Genetic variants had been preselected out of the total number of 8 polymorphisms in candidate genes using Kaplan-Meier method and log-rank tests in dominant, recessive, and codominant mode of allelic expression. sion 1.0  was usedp values. The eNOS 4 a/b, eotaxin −426 C/T, eotaxin −384 A/G, and eotaxin 67 G/A were found to be significantly associated with death, as well as eotaxin −384 A/G with cardiac events. There was also nonsignificant trend for eotaxin 67 G/A to influence the event-free survival.Five hundred thirty-two patients with significant CAD were finally comprised into analysis. The basic characteristics are listed in p = 0.017). As shown below, both polymorphisms were in significant linkage disequilibrium, and the “risky” alleles of both SNPs were frequently inherited together. In the multivariate stepwise Cox regression analysis of cardiac endpoints, a number of diseased coronary arteries  was the only significant independent risk factor. Adding eotaxin −384 A/G into the model did not change the results; that is, although the −384 A/G polymorphism was associated with the hazard of cardiac endpoint both with and without adjustments, it does not provide the prognostic information above the effect of two- or three-vessel disease. Finally, it was determined, whether the variants in eotaxin and eNOS gene were or were not in linkage equilibrium. The analysis revealed modest, but significant linkage disequilibrium (LD) between polymorphisms −426 C/T and −384 A/G in eotaxin gene promoter , as well as between −384 A/G and 67 G/A in the same gene . In this polymorphism, the risky A allele of 67 G/A was more often inherited together with the risky G allele of 384 A/G, suggesting the possible role of LD in resulting effects. On the other hand, −426 C/T and 67 G/A were in linkage equilibrium with each other. In eNOS gene, the eNOS −786 C/T and eNOS 4 a/b polymorphisms were also in significant LD with each other . The B allele of eNOS 4 a/b polymorphism tended to be inherited with the T allele of −786 C/T, while the A allele of the former polymorphism was associated with the C allele of the latter in most cases.Complete data are shown in Tables Many studies have been published about the influence of plasma eotaxin levels and variants of eotaxin gene on presence and severity of atherosclerosis but the results are controversial. Several authors reported an association of higher plasma levels with atherosclerotic burden , 22, 33;p = 0.012; the effect remains significant even after adjusting for body mass index, history of hypertension, the presence of diabetes, and randomized treatment assignment. There was no significant difference between GG homozygotes and heterozygotes. Since there was no information about a treatment in that study, its impact cannot be excluded. The recessive model (AA versus GA + GG) in our study had relatively low power in all cases, there were only 16 AA homozygotes, to detect eventual risky effect of AA homozygote genotype. The linkage disequilibrium between 67 G/A and −384 A/G must be taken into account as well. Unlike the former one, the latter SNP was associated also with cardiac events and the “protective” and “risky” alleles were frequently inherited together.In a large study with 14,916 American men, Zee et al.  studied The influence of genetic variants of different matrix metalloproteinase genes, such as MMP-9 , 48 or M NOS3 gene polymorphisms  with the presence of CAD, but no significance was found for 4 a/b polymorphism in European population. No impact of −786 C/T or 4 a/b on CAD prognosis was found in our study.The association of eNOS polymorphisms with CAD was reported in many studies. The large meta-analysis involving a total sample size of 69,235 subjects  confirmeIn conclusion, a significant association between A allele in eotaxin 67 G/A single nucleotide polymorphism (SNP) in the first exon of the gene and lower survival rate in patients with coronary artery disease was found with and without adjustments for other factors. Similar results were observed for −384 A/G polymorphism in the same gene, which was also associated with cardiac events. Further studies will be needed to elucidate the mechanism of this effect.


By evaluating the number of parity, we identified that parity number of 1, 2 or 3 versus nulliparous demonstrated significant negative association . The dose-response analysis suggested a nonlinear relationship between the number of parity and endometrial cancer risk. The RR decreased when the number of parity increased. This meta-analysis suggests that parity may be associated with a decreased risk of endometrial cancer. Further studies are warranted to replicate our findings.The association between parity and endometrial cancer risk is inconsistent from observational studies. We aimed to quantitatively assess the relationship by summarizing all relevant epidemiological studies. PubMed (MEDLINE), Embase and Scopus were searched up to February 2015 for eligible case–control studies and prospective studies. Random-effects model was used to pool risk estimations. Ten prospective studies, 35 case-control studies and 1 pooled analysis of 10 cohort and 14 case-control studies including 69681 patients were identified. Pooled analysis revealed that there was a significant inverse association between parity and risk of endometrial cancer (relative risk (RR) for parous versus nulliparous: 0.69, 95% confidence interval (CI) 0.65–0.74; I As the most common tumor of the female reproductive tract, endometrial cancer remains the fourth most common malignancy in females3567891011141516Considering that results from individual epidemiological studies can be strongly affected by available sample sizes, a better way to clarify the association between parity and risk of endometrial cancer is to summarize all available evidence from relevant observational studies. In the current study, we aimed to conduct a comprehensive meta-analysis to evaluate this research question. We also conducted analysis to clarify the dose-response relationship between number of parity and risk of endometrial cancer.The detailed procedures of the literature search and article screening were demonstrated in 2 = 76.9%; andp for bias: 0.104). Sensitivity analysis revealed that the 42 study-specific RRs of parous versus nulliparous ranged from as low as 0.69  after omitting the study by Setiawan et al.2 = 74.2%) after omitting the study by Hachisuga et al.7910111518192021222324252 = 0.0%).A total of 42 studies reported the association between risk of endometrial cancer and parity for parous versus nulliparous. After summarizing all available estimates, there was a significant inverse association between parity and endometrial cancer risk (relative risk (RR)  = 0.69, 95% confidence interval (CI) 0.65–0.74), with considerable heterogeneity (I2 = 88.3%), after summarizing estimates from 19 studies (10132627282 = 0.0%). Similarly, after summarizing 13 studies, parity number of 2 versus nulliparous demonstrated a significant inverse association with risk of endometrial cancer , which was also identified in different strata of subgroup analyses (61013262 = 0.0%). Additionally, parity number of 3 versus nulliparous showed a significant inverse association with endometrial cancer risk , after pooling 7 studies.The associations between different number of parity  and endometrial cancer risk were evaluated respectively. Parity number of 1 versus nulliparous was inversely associated with risk of endometrial cancer , with considerable heterogeneity (P for heterogeneity < 0.0001). After testing a potential non-linear relationship, the test for nonlinearity suggested that a non-linear relationship might exist (p for nonlinearity: 0.0058). Under this model the RR also decreased when the number of parity increased. The nonlinear relationship between the number of parity and endometrial cancer risk in females was demonstrated in We performed a comprehensive quantitative meta-analysis to evaluate the relationship between parity and endometrial cancer risk. After summarizing all available evidence, ever giving birth to children was associated with an inverse risk of developing endometrial cancer. The sensitivity analysis demonstrated that the result was not significantly affected by any individual study; also subgroup analyses revealed that the inverse association was detected in all strata. Additionally, analyses assessing each number of parity  demonstrated that the inverse association persisted for all 3 scenarios. Furthermore, we identified a dose-response relationship between the number of parity and risk of endometrial cancer. Overall, our findings support that parity may be associated with risk of endometrial cancer.Our findings are plausible based on understandings from basic research. Estrogens are known to stimulate proliferation of cells in the endometrium and increase mitotic activity, which can induce cancer development303328Our study has several strengths. To the best of our knowledge, this is the first comprehensive meta-analysis evaluating the association between parity and endometrial cancer. Besides conducting subgroup analyses and sensitivity analysis to further evaluate the association, we assessed associations of different numbers of parity and conducted dose-response analysis to fully understand the relationship. Our analyses suggested that the finding of the inverse association between parity and endometrial cancer risk might be robust.2 value should be interpreted with caution because it has certain uncertainty. The value has relatively low statistical power especially in scenarios of small numbers of available studiesSeveral potential limitations need be acknowledged for the appropriate interpretation of our findings. First, we do not have access to the individualized primary data from each of the included studies, which induces the possibility that the risk estimates used in our pooled analysis may not be fully adjusted for. For example, obesity and use of oral contraceptive are among the known factors affecting risk of developing endometrial cancer32In conclusion, based on a summarization of all available evidence from epidemiological studies, parous versus nulliparous was inversely associated with risk of endometrial cancer. There was a nonlinear dose-response relationship between the number of live births and risk of endometrial cancer. Our findings suggested that parity might be a risk factor for endometrial cancer, suggesting roles of reproductive factors in the etiology of endometrial cancer.A literature search of PubMed (MEDLINE), Embase and Scopus databases was conducted from the inception to February 2015. We used the following search keywords: (((((((((parity) OR pregnancy) OR livebirth) OR reproductive) OR reproduction) OR reproductive factors) OR reproductive factor)) AND ((endometrium) OR endometrial)) AND  OR malignancy) OR neoplasm) OR neoplasms) OR cancer) OR cancers) OR adenoma) OR adenomas) OR carcinoma) OR carcinomas). We also screened references of included articles and relevant review papers to identify other potential studies.Studies were eligible if they (i) were prospective studies or case–control studies or pooled analysis of epidemiological studies; (ii) evaluated the association between parity and risk of endometrial cancer; (iii) presented RR, odds ratio (OR), or hazard ratio (HR) values with 95% CI or necessary data for determination. Cross-sectional studies were excluded. Epidemiological studies comparing endometrial cancer cases with controls with gynecology conditions were excluded as well. If we identified multiple articles involving same participants, the study with the largest number of patients and most relevant information was included.Two investigators independently carried out the abstract screening, full text screening, and data extraction. Disagreements were resolved by discussion, with input from other investigators. Data extracted from each study included: the first author’s name, publication year, study country, study design, characteristics of study population . If more than 1 estimate were reported, we used the estimate that was adjusted for the most appropriate covariates, like the previous studies38394041The qualities of included studies were assessed with the Newcastle-Ottawa Quality Assessment Scale2 was used to assess the heterogeneity across studies, where a I2>50% suggests considerable heterogeneityThe RR and 95% CI from included studies were used as the measure of association. Due to the rarity of endometrial cancer, ORs and HRs were deemed equivalent to RRs and RRs were used to represent measures. IWith regards to the dose-response analysis, we explored potential linear relationship between the number of parity and risk of endometrial cancer4850P-value of 0.05 was used as the threshold to determine significant publication bias. All statistical analyses were performed with Stata .Publication bias was evaluated via Begg’s testHow to cite this article: Wu, Q.-J. et al. Parity and endometrial cancer risk: a meta-analysis of epidemiological studies. Sci. Rep.5, 14243; doi: 10.1038/srep14243 (2015).


TYMS) 28 bp repeat polymorphism in 5’UTR region, Cystathionine-Beta-Synthase (CBS) 844ins68bp polymorphism and Solute Carrier (SLC) 19A1 G80A single nucleotide polymorphisms in 80 triads  and 77 matched control mothers in order to observe whether these variants act as risk factors for DS. A significant association was observed for TYMS 5’UTR 28 bp repeat with odds ratio 2.9 . An association which is very close to be significant was observed for SLC19A1 G80A with odds 2.01. Heterozygosity for 68 bp insertion at 844 in CBS showed significant association with odds ratio 10.5 . Transmission disequilibrium test (TDT) for 28 bp repeat polymorphism in TYMS gene presented more than four times greater preferential transmission of maternal two repeats allele whereas paternal three repeats allele had about 1.5 times higher rate of transmission. TDT for SLC19 A1 G80A SNPs revealed preferential transmission of maternal A allele more than two times greater as compared to G allele whereas paternal alleles transmission didn’t show much difference. The result shows that above three polymorphism are significantly associated as a risk factor for predisposition of mother to DS children in the North Indian population.Down syndrome (DS), a chromosomal disorder has higher prevalence in population occurring 1 in 700 live births. Recent reports have shown that almost 92% of the DS children are born from young mothers, suggesting that along with advanced maternal age some other risk factors are involved for predisposition of mother to Down child. Polymorphism in genes involved in folate metabolism as well as insufficient folic acid intake could result in genomic instability, DNA hypomethylation and non-disjunction even resulting in trisomy 21. In present study we compared the frequency of Thymidylate Synthase (


Background. Methylenetetrahydrofolate reductase (MTHFR) SNP rs1801133 has been frequently investigated in recent years. Relevant candidate gene association studies with this SNP and osteonecrosis of the femoral head (ONFH) reported conflicting results. Meta-analysis provides a method to combine these data and to determine the association in a larger sample size. Method. We conducted a systematic search to identify possible studies. Four pooled ORs , along with 95% confidence interval (CI), were calculated to evaluate the association between SNP rs1801133 and ONFH susceptibility. Both fixed effects model and random effects model were used. Findings. We eventually included twelve studies in this analysis, with results showing no overall association between ONFH susceptibility and SNP rs1801133 . When stratified based on ethnicity, the results were still not significant. Conclusion. Our findings are generally supportive of no association between MTHFR SNP rs1801133 and the etiology of ONFH. Osteonecrosis of the femoral head (ONFH) is a painful disorder of the hip and features necrosis of femoral subchondral bone . This diA large number of outstanding researchers have identified multiple factors that genetically contribute to hypercoagulability and osteonecrosis, including protein C and protein S deficiency, factor V Leiden, prothrombin G20210A mutation, and higher lipoprotein levels –10. In rExtensive research into the etiology of ONFH to date has focused on SNP rs1801133. Results of a study by Glueck et al. in 2001 showed that SNP rs1801133 was a genetic risk factor predisposing susceptibility to ONFH . Recentlhttp://www.ncbi.nlm.nih.gov/sites/entrez/) and CNKI (http://www.cnki.net/) electronic database was conducted up to October 1, 2013, to identify all studies investigating the association between SNP rs1801133 and ONFH risk. “Osteonecrosis of the femoral head,” “ONFH,” “Methylenetetrahydrofolate reductase,” “MTHFR,” and “polymorphism” were the keywords we used in the search. The electronic search was complemented with a manual search of citations of all original articles.A systematic search of the PubMed  in control subjects using a chi-squared goodness-of-fit test. To evaluate the strength of the genetic association, four pooled ORs  were calculated, along with the 95% confidence intervals (CIs). A statistical test described by Cochran was conducted to measure heterogeneity between studies . In caseAs shown in PHeterogeneity = 0.027) . This outcome assured the stability and reliability of our results.We observed no significant heterogeneity for SNP rs1801133 under all genetic models with the exception of T versus C (= 0.027) . SensitiP > 0.05). Begg's test also showed that there was little publication bias across studies (P > 0.05)  , 32. TheFurther analysis stratified by ethnicity also showed no association in Asians and in Caucasians. It has previously been reported that CT and TT genotypes have 65% and 30% of the MTHFR activity, respectively, suggesting individuals with these genotypes are at higher risk of various diseases, such as ONFH . A frequResults of a previous meta-analysis showed an association between MTHFR SNP rs1801133 and ONFH in non-Asian populations . In thisThere are some limitations to this study. The ONFH individuals in our study were caused by different etiologies, including primary ONFH without special history, glucocorticoid intake, and alcohol abuse, which may affect the final results. There were significant heterogeneity among the studies, including ethnicity, number of individuals, and methodology. The total sample size may not generate sufficient power to detect the overall and ethnicity-specific effects in subgroups, and minor or moderate association may be masked. Additionally, the nonstandardized selection of control population, such as healthy versus ONFH-free subjects, may introduce nondifferential misclassification bias. Lastly, estimation of age in ONFH susceptibility was not conducted due to lack of original data.In conclusion, the current meta-analysis revealed that MTHFR SNP rs1801133 was not significantly associated with the development of ONFH. We found similar results in ethnicity-specific analysis. Considering ONFH can be caused by many factors such as application of glucocorticoid and alcoholism, these findings need further validation through future larger studies stratified by different etiological factors.


MTHFR) C677T polymorphism is nominated as a potential genetic candidate. However, the synergistic effect of the MTHFR C677T polymorphism with these environmental factors on the risk of hypertension has received little attention. The aim of this study was to explore the associations of the MTHFR C677T polymorphism, environmental factors, and their interactions with hypertension predisposition in a Northern Chinese Han population. A total of 708 participants were enrolled in the study. The genotypes of the MTHFR C677T were determined by a TaqMan assay. We found that participants of an older age, being overweight/obesity, with a smoking habit, drinking habit, or carrying the 677T allele were at an increased risk of hypertension. Additionally, there existed marginally significant interactions of the polymorphism with age and overweight/obesity. However, future large, well-designed studies in Chinese and other populations, as well as mechanistic studies, are still needed to validate our findings, especially considering that the interactions observed in our study were only marginally significant.Hypertension is considered to be the result of genes, environment, and their interactions. Among them age, sex, tobacco use, alcohol consumption, and being overweight/obesity are well documented environmental determinants, and methylenetetrahydrofolate reductase ( MTHFR), an enzyme catalyzing the reduction of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate [MTHFR gene. The incidence of this mutation in the homozygous and heterozygous state is 43.9% and 23.2% in the Chinese population, respectively, which is higher compared with many other populations worldwide [MTHFR C677T polymorphism is expected to be potentially associated with hypertension.Hypertension, the leading risk factor for cardiovascular diseases and premature death, has become a severe public health challenge worldwide. In China, the estimated prevalence of hypertension among adults has increased from 7.5% in 1979 to 25.2% in 2012 ,4. In adrofolate . The enzorldwide . Hyperhoorldwide . TherefoMTHFR C677T polymorphism with hypertension, but the results were inconsistent [Previously, numerous epidemiological studies have explored the relationship of the nsistent . Our prensistent . Severalnsistent ; howevernsistent ,15. Cumunsistent ,16. Theset al. investigated the effect of obesity on relationship of six genetic loci recently identified by genome-wide association studies with hypertension among Chinese children and found five loci were significantly associated with hypertension only in obese individuals [MTHFR C677T polymorphism, its interaction with B-vitamins on cardiovascular diseases, hypertension, and blood pressure lowering has also been extensively investigated [et al. found that the 677TT genotype was associated with an increased risk of coronary heart disease in Europeans but not in North Americans, which was likely to be driven by differences in exposure to B-vitamins, especially folate intake [MTHFR C677T polymorphism and the risk of hypertension received little attention, especially considering that these factors have been shown to, independently or in combination with the MTHFR C677T polymorphism, affect homocysteine levels [MTHFR C677T polymorphism, and their interactions with hypertension predisposition in a Northern Chinese Han population.In recent years, greater emphasis has been placed on the joint effects of genetic and environmental factors on complex disease traits, including hypertension. Two recent studies respectively investigated gene-smoking and gene-alcohol interaction effects on blood pressure using genome-wide data from the Framingham Heart Study and identified several novel blood pressure loci ,16. Xi eividuals . A studyividuals . For thestigated ,20,21. Fe intake . In addie levels . Hence, The study was carried out in the physical examination center of the Dagang Oil Field General Hospital, Tianjin Municipality. We used random number tables  to select study subjects from persons who took regular health examinations during the period between 2010 and 2012. Inclusion criteria were as follows: (1) age ≥18 years; (2) Han nationality; (3) without severe chronic or infectious diseases. In the beginning, 835 persons expressed an interest in our study and agreed to undergo a genotype determination. Then, based on the above inclusion criteria, 127 subjects were excluded, of which 75 had incomplete data and 52 reported histories of diabetes mellitus, cardiovascular diseases, renal diseases, myocardial infarction, or secondary hypertension. Finally, 708 participants were included in formal analysis . The parWe used a self-administered questionnaire to collect data on demographic characteristics, smoking and drinking status, and other health-related information. Smoking status was categorized as current smokers (smoking during the last one year or quit smoking less than six months ago), former smokers (quit smoking more than six months ago), or non-smokers (never smoke). Drinking status were categorized as current drinkers (at least two times/week for men and one time/week for women), former drinkers (quit drinking more than six months ago), or non-drinkers (never drink).2). Overweight/obesity was defined as a BMI ≥ 24 according to the Guidelines on the Prevention and Management of Overweight and Obesity in Adults: China [Body weight, height, and waist circumference were measured using a standard scale with light clothing and barefoot. Body mass index (BMI) was calculated as weight in kilograms divided by the square of height in meters (kg/ms: China . Blood pThe concentrations of triglyceride (TG), cholesterol (TC), high density lipoprotein (HDL), low density lipoprotein (LDL), and fasting blood glucose (FBG) were determined by enzymatic method using a Hitachi Autoanalyzer  .MTHFR C677T were determined by a TaqMan assay, which has been detailed in our previous paper [Genomic DNA was extracted from buccal samples using QiAamp DNA Mini Kit . The genotypes of the MTHFR C677T polymorphism was in accordance with Hardy-Weinberg equilibrium. We also used logistic regression analysis to examine the potential effects of the MTHFR C677T polymorphism on hypertension risk under five genetic models . Then, we used the methods suggested by Thakkinstian et al. to select the most appropriate genetic model [Differences in the distribution of baseline characteristics between hypertensive and normotensive groups were tested using student’s t-test for continuous variables  and chi-square test for categorical variables . All of the continuous variables were tested for normality before Student’s t-test, and those non-normally distributed variables were log-transformed to reach normality and variance homogeneity. Logistic regression analysis was used to examine the associations of age, gender, BMI, drinking, and smoking status with hypertension susceptibility. We coded age ≤45 years = 0, and age >45 years = 1 (the mean age of the study subjects was 45.60 years); normal weight = 0, and overweight/obesity = 1. As the number of former-drinkers and former-smokers were too small to deduce valid results, we coded non-drinkers = 0, ever-drinkers (current-drinkers and former-drinkers) = 1, and non-smokers = 0, ever-smokers (current-smokers and former-smokers) = 1. A goodness of fit chi-square test was used to evaluate whether the genotypic distribution of the ic model .MTHFR C677T polymorphism was dichotomized under dominant genetic model (the selected genetic model) in which TT and CT genotypes were combined, and we use the combined genotype as the “at risk” genotype for easy interpretation. Similarly, environmental characteristics were dichotomized by appropriate grouping noted above. Furthermore, relative excess risk due to interaction (RERI) and corresponding 95% confidence interval (CI) were calculated to evaluate the presence of interactions on the additive scale. The RERI is a measure of difference in excessive relative risks, and we calculated RERI and its 95% CI using an Excel sheet downloaded from Epidemiological net [MTHFR C677T genotype group. In addition to the calculations of RERI and its 95% CI, all other statistical analyses were conducted using SAS software . A two tailed p value less than 0.05 was taken as statistically significant.Subsequently, multivariable-adjusted stratified analyses were used to explore potential gene-environmental interactions based on the most appropriate genetic model. The ical net . If absep < 0.05).A total of 708 subjects including 518 males and 190 females were finally included in the present study. p = 0.038 to <0.001). After adjustment for multiple covariates, the association of age >45 years, being male, overweight/obesity, and ever-drinkers with hypertension was still statistically significant with an OR of 2.63 (95% (CI): 1.84–3.76, p < 0.001), 1.81 , 2.78 , and 1.60 , respectively. However, the relationship of smoking status with hypertension failed to reach significance (p = 0.743).MTHFR C677T polymorphism are summarized in p = 0.20). The frequency of the MTHFR 677T allele in the hypertensive group (60.77%) was significantly higher than the normotensive group (53.76%) (p = 0.004). We further investigated the associations of the MTHFR C677T polymorphism with hypertension risk using the unconditional logistic regression analysis under five genetic models. In the univariate analysis, the MTHFR C677T polymorphism was significantly associated with hypertension under the homozygous co-dominant, dominant, and allelic models. After adjustments for age, gender, BMI, and smoking and drinking status, significant association was still observed in homozygous co-dominant  and dominant  models.Genotypic and allelic frequencies for the MTHFR C677T polymorphism with dichotomous age, gender, BMI, smoking status, and drinking status on hypertension risk. Compared with younger subjects with CC genotype, the hypertension risk among subjects who were older and carried the “at risk” genotype  was much greater than those who were older with CC genotype  and among subjects who were younger with the “at risk” genotype . The corresponding RERI was 1.26 , suggesting a marginally significant interaction on the additive level.p = 0.001), which is greater than the independent ORs for the “at risk” genotype  and overweight/obesity , with an RERI of 1.33 . No apparent combined effect between sex, drinking status, smoking status, and the polymorphism was found.In addition, we found that the strongest effects of age on blood pressure levels was in the 677TT genotype carriers, followed by 677CT genotype and 677CC genotype carriers . SimilarMTHFR C677T polymorphism, several environmental factors, and their interactions on the development of hypertension among the Northern Chinese Han population. Participants with older age, high BMI, smoking habits, drinking habits, or carrying the 677T allele were at increased risk of hypertension. Furthermore, we observed some indications for interactions of the MTHFR C677T mutant genotype with older age and being overweight/obesity.In this study we systematically explored the effects of the MTHFR C677T polymorphism with hypertension, but the results were controversial [et al. included nine studies conducted among the Chinese population, four of which reported a significant association between the C677T polymorphism and essential hypertension, but the remaining five did not [MTHFR C677T polymorphism is related to hypertension in one population, but not in another population. Among them, gene-environment interaction could not be neglected as our current understanding of pathogenesis of hypertension indicates a multifactorial and multistep process including various genetic and environmental factors.Numerous prior epidemiological studies have investigated the association of the oversial ,28. A re did not . In the MTHFR C677T polymorphism with several environmental factors, and found that the joint effects of the “at risk” genotype with older age and being overweight/obesity were greater than the sum of their individual effects. The RERIs for the interaction of older age and being overweight/obesity with the “at risk” genotype were 1.26 (95% CI = −0.33–2.85) and 1.33 (95% CI = −0.15–2.80), respectively, indicating an OR that is 1.26 and 1.33 times higher, respectively, as a result of the interaction. Notably, the calculated lower confidence limits for both RERIs were less than, but close, to zero, meaning that the interactions were marginally significant. One possible explanation for the marginally significant interaction might be the relatively small sample size of the present study, especially in some subgroups.We further explored possible interaction effects of the MTHFR C677T polymorphism interact to influence the development of hypertension remain unclear. However, both older age and the 677T allele can cause hyperhomocysteinemia and aberrant DNA methylation [MTHFR C677T polymorphism on plasma homocysteine concentrations has been reported [MTHFR C677T polymorphism and age on hypertension may be partially due to their interactive effects on homocysteine concentrations and DNA status. The age-gene synergism observed in this study may be biologically plausible and expected.The precise mechanisms by which age and the hylation ,29,30,31hylation . Furtherreported . Therefoet al. observed that the MTHFR C677T polymorphism was significantly associated with hypertension only in obese children [et al. showed that the MTHFR C677T polymorphism interacted with overweight/obesity to modulate serum lipid levels [MTHFR C677T polymorphism and overweight/obesity on dyslipidemia may be a partial reason for their joint effects on hypertension found in this study. In spite of this, the biological mechanisms by which overweight/obesity modifies the relationship between the MTHFR C677T polymorphism and hypertension risk remain unclear and just can be speculated. Further studies are therefore still warranted to investigate the precise mechanism of the interaction in the pathogenesis of hypertension.Consistent with our findings on the potential interaction between the polymorphism and being overweight/obesity, a large population-based case-control study among Chinese population by Xi children . Overweichildren . Some ofchildren . Additiochildren ,35. Furtchildren ,37. Furtd levels . In the et al. observed no association between cigarette smoking and hypertension in a Guangxi Bai Ku Yao population; however, they found that cigarette smoking showed interaction with the MTHFR C677T polymorphism to affect blood pressure levels [et al. found interactive effects of alcohol consumption with the MTHFR C677T polymorphism on hypertension [et al. [vs. Han (the present study)), sample size, dietary habits, and other environmental exposures.The relationship between cigarette smoking and hypertension is controversial. Some investigators reported that cigarette smoking can increase the risk of hypertension, while others reported that it was associated with reduced hypertension risk, and some found no direct association between them ,40,41. He levels . In conte levels . Therefortension , which w [et al. ,43 can b [et al. ,43 vs. HMTHFR C677T polymorphism with age, being overweight/obesity, gender, alcohol drinking, and cigarette smoking on hypertension predisposition.In interpreting the findings of our study, several limitations need to be considered. Firstly, this study used a cross-sectional design, which precludes causal inference. Secondly, the study subjects were recruited from only one hospital, which compromises the representation of the general population and our findings may not be generalizable to the whole Chinese population, although the genotype distribution of the polymorphism in our study subjects complied with the Hardy-Weinberg equilibrium. Thirdly, selection bias is possible because the majority of the study participants were workers in the Dagang Oil Field, and there were significantly more male subjects than females. The significant gender difference in the number of study subjects also makes it difficult to draw conclusions regarding gender. Fourthly, because we used a questionnaire to collect personal exposure information (such as smoking and drinking), the responses might be influenced by the participant’s memory, so recall bias cannot be excluded. Fifthly, some information on relevant potential confounders, such as menopause status, dietary habits , physical activity, and other genes were not included and controlled in this study. This could have affected the accuracy of our estimates. Despite these limitations, our study still has several apparent advantages. First, the study was carried out in a northern region where 677TT genotype frequency was high according to our previous findings [MTHFR 677T allele is associated with an increased risk of hypertension. Additionally, these results suggest a potential synergistic effect of the polymorphism with age and BMI on hypertension susceptibility. Our findings provide a further insight on the gene-environment relationships involved in hypertension pathogenesis. However, future large, well-designed studies in Chinese and other populations, as well as mechanistic studies, are needed to validate our findings, especially considering that the interactions observed in our study were marginally significant.In summary, the results of the present study suggest that the


I2 = 41.9%, P = 0.099, n = 8) when comparing women with oldest category of menarcheal age with women with youngest category of menarcheal age. Notably, there was an 4% reduction in risk for per 2 years delay in menarcheal age . Additionally, significant inverse associations were consistent within all stratified analyses. There was no evidence of publication bias or significant heterogeneity between subgroups detected by meta-regression analyses. Our findings support the hypothesis that late menarcheal age is inversely associated with endometrial cancer risk. Further larger prospective or pooled studies are warranted to fully adjust for potential confounders and distinguish whether the associations differ by histological subtypes of endometrial cancer.Evidence between age at menarche and endometrial cancer risk have been controversial. Therefore, we conducted a meta-analysis of prospective studies to analyze the aforementioned association. Relevant studies were identified by searching PubMed and EMBASE databases until the end of June 2015. A random-effects model was used to estimate summary relative risks (RRs) and 95% confidence intervals (CIs) for associations between menarcheal age and endometrial cancer risk. Our meta-analysis included eight prospective studies involving 4553 subjects with endometrial cancer. The summarized RRs of endometrial cancer for menarcheal age were 0.68 (95%CI = 0.58–0.81,  Of these, 4593 articles were excluded after the first screening based on the abstract or title, leaving 14 articles for full-text review. On this review, two articles222425269212829303128293031versus the youngest categories of menarcheal age was 0.68 (95% CI: 0.58–0.81) with moderate heterogeneity  (P-bias = 0.189) and no asymmetry in the funnel plots when inspected visually.The summary RR of endometrial cancer for the oldest = 0.099) , Fig. 2.I2 = 45.7%, P = 0.101) (P-bias = 0.152) and no asymmetry was observed in funnel plots when inspected visually. There was no evidence of a nonlinear association between the menarcheal age and endometrial cancer risk (P for nonlinearity = 0.16).Six studies were included in the dose-response analysis921282930= 0.101) , Fig. 3.In subgroup analyses, possible differences between risk estimates by various study characteristics were examined. The finding of decreased endometrial cancer risk with later menarcheal age was consistently observed in almost all of the stratified analyses, although not all strata showed statistical significance. Furthermore, there was no evidence of significant heterogeneity between subgroups detected by meta-regression analyses . When stversus youngest menarcheal age ranged from a low of 0.65  after omission of the study by Yang et al.I2 = 0%, P = 0.461) after omission of the study by Wernli et al.I2 = 15.7%, P = 0.314) after omission of the study by Yang et al.I2 = 10.7%, P = 0.345) after omission of the study by Wernli et al.In a sensitivity analysis, we sequentially removed one study at a time and re-analyzed the data. The 8 study-specific RRs of the oldest To the best of our knowledge, this is the first comprehensive and quantitative assessment to explore the relationship between menarcheal age and risk of endometrial cancer. Overall, menarcheal age was found to be associated with an estimated 32% reduction in endometrial cancer risk when the oldest menarcheal age category compared to the youngest. Additionally, the results of dose-response analyses suggested an 4% reduction in endometrial cancer risk for per 2 years delay in menarcheal age . These significant results were consistent within subgroup analyses and across sensitivity analyses.P trend = 0.04), which partly supported the findings of this meta-analysis. However, none of the included studies of this meta-analysis demonstrated the information of different histological type which limited us to confirm their finding. On the other hand, Type I endometrial cancers are mostly endometrioid adenocarcinomas, which seem to develop from abnormal glandular proliferations  driven by hormonal mechanisms. In contrast, Type II endometrial cancers often display serous or clear cell histology and arise from atrophic endometrium in a less hormonally dependent manner. In addition, subtypes of these cancers are characterized by distinctive molecular alterations, and endometrioid carcinomas are more clearly linked to elevated levels of sex-steroid hormones and expression of hormone receptors2837et al.et al.et al. reported that the youngest and oldest category of menarcheal age in a cohort study with 24,848 women which was carried out in Iowa was less than 11 years and over than 14 years, respectively. Since this, the interpretation of the results when using the oldest category of menarcheal age compared to the youngest should be cautiously. However, the results of dose-response analysis which could reduce the impact from the different category of menarcheal age of these included studies were in accordance with the results of oldest versus youngest category analysis which not only demonstrated the findings of this meta-analysis were robust but suggested that this aforementioned association was independent of the category methods. On the other hand, several genome-wide association studies (GWAS) have identified that genetic factors may associated with menarcheal age394041The association between hormonal risk factors and endometrial cancer risk could be partly attributed to the “unopposed estrogen” hypothesis. This hypothesis proposes that exposure to estrogen, in the absence of sufficient progestin, leads to increase mitotic activity, DNA replication, and somatic mutations of endometrial cells that may result in malignant transformations23453489202123A strength of this study is that it included a relatively larger sample sizes than any other individual studies with a total of 4553 endometrial cancer cases and approximately 949,945 non-cases. Thus, we had statistical power to detect moderate and weak associations and carry out subgroup analyses by potential confounding factors and study characteristics. Another important strength of this meta-analysis was that we included all the prospective design studies and the results are unlikely to be explained by the bias of traditional retrospective studies.et al.This study, however, also has limitations. First, since all included prospective studies were based on the observational design, it is possible that these aforementioned observed significant inverse associations could be due to the unmeasured or residual confounding. Many factors known to affect endometrial cancer risk, especially BMI12In summary, this meta-analysis suggested that later menarcheal age was inversely associated with the risk of endometrial cancer. Further studies, especially large consortium or pooled studies would be of interest to fully adjust for potential confounders and distinguish whether other risk factors which closely associated with both menstruation span and hormone change  might have the similar inverse association with endometrial cancer risk and whether these associations might differ by the histological subtypes of endometrial cancer.We performed a comprehensive literature search to the end of June 2015 using the MEDLINE (PubMed) and EMBASE databases limited to the studies of humans by using the following search key words and Medical Subject Headings terms: (menarche OR reproductive factors OR reproduction) AND  AND (cancer OR neoplasm OR carcinoma OR tumor). Additionally, the reference lists of retrieved articles were also scrutinized for additional studies by manual search. A similar search strategy was utilized for our previous meta-analysis of menarcheal age and ovarian cancerPublished studies were included by the following selection criteria if they 1) used a prospective study design, including cohort, case-cohort, and nested case-control studies; 2) evaluated the association between menarcheal age and incident endometrial cancer risk; and 3) presented relative risk (RR) or hazard ratio (HR) estimates with 95% confidence intervals (CI), standard errors (SE) or data necessary to calculate these.Published manuscripts were excluded by the following exclusion criteria if they 1) had a retrospective design; 2) the estimates were presented without SE or other information that allowed calculation of SE; 3) reported exclusively on endometrial cancer mortality. When multiple publications from the same study were available, we used the publication with the largest number of cases and most applicable information.All above study selection and exclusion procedures were carried out by two independent investigators (T-TG and X-XM).versus youngest category of menarcheal age , and factors matched between cases and controls in nested case-control study and potential confounders adjusted in the data analysis.For each eligible study, two investigators (T-TG and X-XM) independently performed the eligibility evaluation and data abstraction. Discrepancies were settled by consensus or by involving a third reviewer (Y-LW) for adjudication. Data abstracted from each study were: author list, year of publication, country where the study was performed, study design, study sample size (number of cases and cohort size), range of follow-up for cohort studies, exposure and outcome assessment and menarcheal age categories, study-specific adjusted RRs or HRs with their 95% CIs for the oldest Since all included studies are prospective study and similar to our previous studies11et al.The study-specific adjusted RRs were used as the common measure of association across studies. For the meta-analysis, we assumed that estimates of risk, rate or hazard ratios from prospective studies were all valid estimates of the RR and we therefore report all results as the RR for simplicity. For study of Yang I2 statisticsI2 statistic represents the proportion of total variation contributed by between-study variationThe possible heterogeneity in results across studies was examined by using the et al.et al.921282930P value by testing that these two regression coefficients were simultaneously equal to zero. We calculated a P value for nonlinearity by testing that the coefficient of the second spline was equal to zero. The details of this method has been published elsewhere53For the dose-response analysis, we used the generalized least-squares trend estimation method developed by Greenland versus ≥10 years), number of cases (<400 versus ≥400), method of exposure assessment (self-administered questionnaire versus trained interviewers), study population (American versus Non-American), and factors matched between cases and controls in nested case-control study and potential confounders adjusted in the data analyses . Finally, sensitivity analysis was executed by deleting each study in turn to reflect the influence of individual data set on the overall estimate.To investigate possible sources of heterogeneity of main results, we carried out stratified analyses by the following study features: duration of follow-up . P-values were two sided with a significance level of 0.05.Small study bias, such as publication bias, was evaluated by Egger’s linear regressionHow to cite this article: Gong, T.-T. et al. Age at menarche and endometrial cancer risk: a dose-response meta-analysis of prospective studies. Sci. Rep.5, 14051; doi: 10.1038/srep14051 (2015).


Objective. Several studies with contradictory results from different cultures about association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in schizophrenia and bipolar disorders. Little is known about this association in Arab culture and Egypt. So the present study aimed to assess the association of MTHFR C677T polymorphism in bipolar disorder (BD) and schizophrenia in comparison to control group. The association between MTHFR C677T polymorphism and the age at onset in schizophrenia or BD was also studied. Methods. Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) were used to examine the genotype and allele frequencies of MTHFR C677T polymorphism in 149 healthy subjects and 134 bipolar and 103 schizophrenia patients. Results. In BD and schizophrenia, there was a higher prevalence of MTHFR C677T polymorphism than healthy subjects. Earlier age at onset was found in patients with BD, carrying one copy of the T allele or CT genotypes but not in patients with schizophrenia. Conclusion. The present findings suggest that the MTHFR C677T polymorphisms are likely to be associated with the risk of developing BD and schizophrenia and influence the age at onset of BD but not the age at onset of schizophrenia. Schizophrenia and bipolar disorder (BD) are functional psychiatric disorders that have been linked to low folate levels and defective folate metabolism , 2. SchiMTHFR gene is located at the end of the short arm of chromosome 1 (1p36.3). The enzyme plays a central role in folate metabolism by irreversibly converting 5, 10-methylenetetrahydrofolate  to 5-MTHF, the predominant circulating form of folate . 5-MTHF Common single nucleotide polymorphisms in MTHFR have been reported, a C/T transition at nucleotide 677 in exon 4 (rs1801133)  that cauAge at onset in schizophrenia is variable and may occur in early childhood or late in life  and has The aim of this work was to investigate the possible role of the MTHFR C677T polymorphism in the risk of developing BD and schizophrenia and also to study the association between this polymorphism and the age at onset in both psychiatric disorders.First 6-month duration of this study was spent to select suitable patients who could participate in this study by examining all patients who came to the Department of Psychiatry (inpatient and outpatients clinics) attached to Mansoura University Hospital for any cause . At the end of this 6-month study, 621 patients fulfill the Diagnostic and Statistical Manual 4th edition—Text Revision (DSM IV-TR) criteria for either of schizophrenia or mood disorder bipolar I . All patAt the end of this survey and after explaining to the patients and their relatives the aims of this study, 186 patients refuse to participate in the study or refuse to give a blood sample. Also 165 patients were not included in the study because they met one of the exclusion criteria. Exclusion criteria were subjects with a history of brain injury; neurological disorders; psychiatric disorders due to general medical conditions or substance abuse; or subjects related to an individual already included in the study. Also 33 patients with some chronic medical diseases or known genetic disease were excluded. Finally, 237 patients completed this study (103 patients diagnosed with schizophrenia and 134 patients diagnosed with BD). The clinical data were summarized in 149 healthy volunteers (control group) were randomly recruited from relatives of other patients in the Medicine Department, outpatient clinic, in the same hospital, with negative family or past history of any psychiatric disorders and with no family relationship to the present study patients. A written informed consent was obtained from all participants. The study was approved by the local ethics committee. The study has been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki.From all participants, 5 mL venous blood samples were obtained on EDTA containing tubes. Genomic DNA was isolated from peripheral blood leukocyte using the Gentra Puregene Blood Kit . The extracted DNA was stored at 4°C until analysis.μL, containing 1.8 mM MgCl2, 1 U Taq polymerase, 2.5 mmol/L of each dNTP, 5 pmol/L of each primer, and 100 ng of genomic DNA, processing starts with 94°C for 5 min and 34 cycles at 94°C for 45 s, 62°C for 40 s, and 72°C for 50 s. This was followed by a final extension at 72°C for 7 min. Then, 5 U of FastDigest HinfI  was added to the PCR products (5 μL) and digested at 37°C for 30 minutes. After restriction enzyme digestion of the amplified DNA, genotypes were identified by electrophoresis on 3% agarose gels and visualized with ethidium-bromide staining ultraviolet illumination.Genotyping of the MTHFR C677T was performed by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) , 29. PCRAfter the genomic DNA of the samples was amplified by PCR and imaged, the purpose gene of 245 bp nucleotide sequences was studied. The genotypes identified were named according to the presence or absence of the enzyme restriction sites, when a C to T transversion at nucleotide position 677 of the MTHFR gene occurs. The presence of the cutting site indicates the T allele, while its absence indicates the C allele. Thus, the CC genotype is homozygote for the absence of the site (band at 245 bp), CT genotype is heterozygote for the absence and presence of the site , and TT genotype is homozygote for the presence of the site (bands at 173 and 72 bp).t-test and ANOVA test. Statistical significance was defined as P < 0.05. Qualitative variables were expressed as number and percentages. The allele frequencies in the groups of affected subjects and controls were compared using a Chi-square statistic with 1 degree of freedom. The Hardy-Weinberg test was done to examine whether the allele and genotype frequencies in the studied groups remain constant from generation to generation in the absence of other evolutionary influences or not. Linear regression analysis was done for age of onset as the dependent variable and allele frequency as a predictor factor.All statistical analyses were done with the SPSS 20.0 package . Quantitative data were summarized using mean and stander deviation (SD). The statistical significant difference between patient and control groups was tested using P ≤ 0.000, and OR (CI) = 0.313 (0.182–0.538), P = 0.000, resp.), while the CT genotype distribution is significantly increased in BD and schizophrenia groups versus control group (OR (CI) = 4.34 (2.57–7.33), P≤0.001 and 2.131 (1.21–3.77) P = 0.009, resp.). Also, the TT genotype distribution is significantly increased in BD and schizophrenia groups versus control group (OR (CI) = 9.47 (1.61–12.4), P = 0.002 and 4.91 (1.72–13.98) P = 0.001, resp.). The C allele is significantly prevalent in the control group compared to the BD and schizophrenia groups (OR (CI) = 0.17 (0.08–0.36), ≤0.001, and OR (CI) = 0.18 (0.09–0.38), P ≤ 0.001, resp.), while T allele is prevalent in BD patients and schizophrenia patients compared to the control group with a statically significant difference (OR (CI) = 6.57 (4.24–10.17), P < 0.001, and OR (CI) = 3.62 (2.29–5.71) P < 0.001, resp.). For schizophrenia patients, there is a significant decrease in mean age at onset with the TT genotype compared to CT genotype (P = 0.046). The presence of one copy of the wild C allele showed older age at onset in BD patients (P = 0.032) and the presence of one copy of T allele is associated with earlier age of onset in BD (P≤0.001). On the other hand, in schizophrenia, none of T or C allele was associated with a significant difference in mean age at onset (P = 0.66 and P = 0.10). In addition, From The elucidation of etiology and pathophysiology of the disease is extremely important to establish treatment and prevention strategies . SchizopThe present study showed an association of MTHFR C677-T polymorphism with BD as CT, TT genotypes and T allele is more prevalent in BD patients. This result is in part in accordance with Kempisty et al.  that indP value, the odds ratio and confidence interval provided some evidence of increased risk for individuals with the T-containing genotypes. And the role of this polymorphism in the pathogenesis of schizophrenia and BD could not be ruled out [On the other hand, Tan et al.  found thuled out . Chen etuled out  also fouuled out .Moreover the meta-analyses conducted by Zintzaras  and CoheThe current study also showed an association between MTHFR C677-T polymorphism and schizophrenia as TT genotype and T allele are more prevalent in schizophrenia patients. This result is in harmony with that of Zintzaras  who founAlso, this result is partially in accordance with that of Lajin et al.  who founMTHFR is a crucial enzyme involved in one-carbon metabolism, which is a folate-mediated pathway . It is aDNA methylation is a critical epigenetic modification of the genome that controls many biologic processes, including embryonic development, X chromosome inactivation, imprinting, and gene expression , 46. MetSchizophrenia is increasingly considered to be a neurodevelopmental disorder, with in utero exposures and epigenetic mechanisms such as DNA methylation being important in its etiology . BesidesThe absence of clear evidence of major genetic effects, despite (high) estimates of heritability for major psychiatric disorders, together with evidence of “causal” environmental exposures resulting in changes in gene expression is consistent with the concept that the biologic underpinnings of psychiatric disorders are epigenetic in form rather than DNA sequence based . This foThis study also showed an association between MTHFR C677T polymorphism in genotype CT and T allele frequencies with earlier age at onset of BD. To our knowledge, no study examines age of onset in BD and its association with MTHFR C677T polymorphism. But for schizophrenia, in this study, there was no association between MTHFR C677T polymorphism in genotype and allele frequencies with the age at onset. This result is in harmony with studies by Peerbooms et al.  and SaetThe observed heterogeneity in the associations between MTHFR polymorphisms and age of onset between studies may reflect heterogeneity in the assessed trait and gene-environment and/or gene-gene interactions . Also, iOne limitation of this study is the unavailability of studies in Arab countries examining this gene and any other genetic studies in general. This makes comparison with previous studies from Arab countries so difficult, so we compare the present results with results in other (Caucasian) populations.In conclusion, the present study provides evidence that the MTHFR C677T variants may influence the risk of developing BD and schizophrenia. Furthermore, the polymorphism may influence the age at onset of BD but not the age at onset of schizophrenia. Additional genetic studies are needed to further analyze this topic.


The aim of the present study was to evaluate the influence of tumor necrosis factor-alpha (TNF-α) −308 G > A polymorphism on hepatocellular carcinoma (HCC) risk.The present case–control study was conducted in a Han Chinese population consisting of 753 HCC patients and 760 controls from May 2010 to March 2013. The −308 TNF-a promoter polymorphisms were detected. Conditional logistic regression was performed to analyze the association between TNF-α −308 G > A polymorphism and the risk of HCC, which were estimated by odds ratios (ORs) and their 95% confidence intervals (95% CIs).P = 0.002). Using the GG genotype as the reference genotype, AA was significantly associated with increased risk of HCC . Similarly, AG + AA genotype showed 5.59-fold increased HCC risk in a dominant model. Furthermore, we found A allele was significantly associated with increased risk of HCC, compared with G allele .The genotypic frequencies in the cases were not similar to that of the controls, differences being statistically significant  for this article can be found here:  Hepatocellular carcinoma (HCC) is one of the common malignant tumors globally, which is the fifth most prevalent cancer and the third cause of cancer-related deaths worldwide . ApproxiTumor necrosis factor-alpha (TNF-α) encodes a pro-inflammatory cytokine that is secreted primarily by macrophages and plays critical roles in the pathogenesis of inflammatory autoimmune and malignant diseases. The TNF-α protein induces the expression of adhesion molecules, facilitating the invasion of metastatic tumor cells , and higThe present case–control study consisted of 753 HCC patients and 760 cancer-free controls from May 2010 to March 2013 at the Digestive Disease Department, Shandong Provincial Hospital Affliated to Shandong University. All subjects were unrelated Han Chinese living in China. Health subjects were randomly selected from health screening program participants to exclude those with a history of cancer and other medical diseases. All HCC patients were diagnosed on the basis of histology or the combination of typical radiological findings of HCC, and underwent surgery in Shandong Provincial Hospital Affliated to Shandong University. The tumor stage of HCC cases was evaluated on the basis of the tumor-nodule-metastasis (TNM) classification system. The HBsAg and anti-hepatitis C virus (HCV) antibody were tested by microparticle enzyme immunoassays using commercial assay kits, which were used to determine the infection status of hepatitis B or hepatitis C. Clinical characteristics data as well as related risk factors, including gender, age, smoking status, drinking status, serum a-FP levels, family history of HCC and HBV, HCV serological markers, were summarized (Table A 5 mL sample of venous blood was collected from each subject into a test tube containing EDTA as anticoagulant. Genomic deoxyribonucleic acid (DNA) was extracted from 2 mL of peripheral blood by the standard method with proteinase K digestion followed by phenol–chloroform extraction. After ethanol precipitation, the DNA was dissolved in double distilled water and frozen at −20°C until use.2, 1× PCR buffer and 2.5 U Taq DNA polymerase . The following cycling conditions were used: 95°C for 5 min, followed by 35 cycles of 94°C for 60 s, 58°C for 30 s and 72°C for 60 s, with a final extension at 72°C for 10 min. Restriction enzyme digestion with NcoI  of the PCR product was carried out overnight and analyzed on a 3% agarose gel. DNA products were visualized by ethidium bromide staining. The -308G showed two fragments , while its homologue -308A was undigested and resulted in a single band . The presence of all three fragments defined heterozygotic individuals.The −308 TNF-a promoter polymorphisms were determined by method previously described . Amplifi2 test was used to assess differences between cases and controls with regard to clinical characteristics. A goodness-of-fit χ2 test was used to evaluate the Hardy-Weinberg equilibriums in controls. Conditional logistic regression was performed to analyze the association between TNF-α −308 G > A polymorphism and the risk of HCC, which were estimated by odds ratios (ORs) and their 95% confidence intervals (95% CIs). The significance levels of all tests were set at P <0.05.All statistical analyses were performed using the Statistical Package for Social Science software version 18.0 . Continuous variables were reported as means ± standard deviation (SD), and categorical variables were reported as frequencies (N) and percentages (%). The χP >0.05, shown in Table In the present case–control study, a total of 1,513 Chinese Han subjects were enrolled, which consisting of 753 HCC patients and 760 cancer-free controls. Table P > 0.05). Compared to healthy controls, patients with HCC had lower frequency of GG genotype (81.1% vs. 96.4%) and a higher frequency of AG (13.0% vs. 3.2%). Homozygous AA genotype was found in 44 HCC patients and in 2 of controls. Thus, genotypic frequencies in the cases were not similar to that of the controls, differences being statistically significant . Their results suggested that the TNF-α-308 G > A polymorphism might significantly contribute to prostate cancer susceptibility [TNF-α is a member of the TNF/TNFR cytokine superfamily, and is an intercellular communicating molecule involved in building transient or long-lasting multicellular structures . It intetibility . Howevertibility -15. The tibility ,21, but tibility .In conclusion, the present study showed that TNF-α −308 G > A polymorphism was associated with increased HCC risk in a Han Chinese population. Further prospective studies on large and different ethnic populations will be necessary to confirm our findings and elucidate the underlying molecular mechanism for the development of HCC.