Many epidemiological studies have been conducted to explore the association between a single CYP2D6 gene polymorphism and Parkinson’s disease (PD) susceptibility. However, the results remain controversial.CYP2D6 gene polymorphism on the risk of PD, a meta-analysis of all available studies relating to CYP2D6*4 polymorphism and the risk of PD was conducted.To clarify the effects of a single A comprehensive literature search of PubMed, EMBASE, and the China National Knowledge Infrastructure (CNKI) up to September 1, 2013 was conducted. Data were extracted by two independent authors and pooled odds ratio (OR) with 95% confidence interval (CI) were calculated. Meta-regression, Galbraith plots, subgroup analysis, sensitivity analysis, and publication bias analysis were also performed.CYP2D6*4G/A polymorphism and PD risk in all of the comparisons . In subgroup analysis stratified by ethnicity, significant associations were also demonstrated in Caucasians but not in Asians. No significant association was found in subgroup analysis stratified by age of onset or disease form.Twenty-two separate comparisons consisting of 2,629 patients and 3,601 controls were included in our meta-analysis. The pooled analyses showed a significant association between CYP2D6*4G/A polymorphism denotes an increased genetic susceptibility to PD in the overall population, especially in Caucasians. Further large and well-designed studies are needed to confirm this association. We concluded that the  CYP2D6  gene polymorphism and PD in Caucasians [CYP2D6 gene [Parkinson’s disease (PD), a progressive neurodegenerative disorder, is clinically characterized by bradykinesia, rigidity, resting tremor, and postural in-stability . The etiucasians -5. Furth2D6 gene .CYP2D6 is a highly polymorphic member of the cytochrome P450 family located on chromosome 22q13 [CYP2D6 is the G to A substitution at position 1,934 in the junction of intron3/exon4 (CYP2D6*4), also called the CYP2D6B or CYP2D629B mutant allele [me 22q13 . The majt allele . TherefoCYP2D6 and risk of PD has been studied by a number of authors; however, results remain controversial. Studies by Armstrong et al. [CYP2D6*4 confer a two-fold increase in odds ratio (OR) for PD patients compared to healthy control individuals. On the other hand, no significant difference in mutation frequency was found in studies conducted by Plante-Bordeneuve et al. [CYP2D6 mutant alleles (21%) [CYP2D6 polymorphisms denote a susceptibility to developing PD. We therefore performed a systematic review and meta-analysis to quantitatively assess the association between CYP2D6*4 allele polymorphism and PD risk.The hypothesis toward poorer metabolism of debrisoquine 4-hydroxylase caused by a defect in g et al.  and Smitg et al.  reportede et al.  and Atkie et al. . Determies (21%) , could hcytochrome P450 CYP2D6 OR CYP2D6” and “Parkinson OR Parkinson’s disease” and “polymorphism, mutation OR variant”. No language restrictions were applied. The reference lists of relevant articles were checked manually to find additional eligible studies and no attempts were made to identify unpublished studies. A comprehensive literature search of PubMed, EMBASE, and the China National Knowledge Infrastructure (CNKI) covering all articles published up to September 1, 2013 was conducted using the search strategy based on combinations of the keywords “CYP2D6*4 allele polymorphism and PD; ii) case-control studies; and iii) studies with sufficient data available to estimate the OR with their 95% confidence intervals (95% CIs). Exclusion criteria included: i) articles without sufficient information for data extraction and ii) articles that only assessed the association between CYP2D6 and PD in phenotype or other alleles. If dual or multiple studies were reported by the same institution or authors, either the one of higher quality or the most recent study was included in the analysis.This study was performed according to the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines for reporting . InclusiP value for control population in Hardy-Weinberg equilibrium (HWE), and the onset age of PD patients as well as the form of the disease . If different results were generated, discrepancies were discussed to reach consensus. Considering the subgroup of ethnicity, subjects were grouped into the main racial group of the study population according to their geographical origin or ancestry [Two investigators (Xue Qin and Yu Lu) independently extracted data from the studies included. The following variables were extracted: first author’s name, year of publication, country, ethnicity, genotyping method, number of cases and controls, source of controls, genotype distribution in cases and controls and ancestry .To evaluate the quality of the included studies, two investigators (Cuiju Mo and Zhiyu Zeng) assessed them independently based on a set of predetermined criteria which was initially proposed by Thakkinstian et al.  and has CYP2D6*4 allele polymorphism and PD risk. The following contrasts were evaluated: i) a comparison of variant alleles with a wild allele ; ii) a comparison of each homozygote with the other combined with a heterozygote ; and iii) a comparison of a variant homozygote with a heterozygote and a wild homozygote . Subgroup analyses were also conducted to evaluate the effect of CYP2D6*4 allele polymorphism on the susceptibility to PD in different populations (Asian and Caucasian); different onset age of PD patients (grouped as early onset age (E): <51 years old, late onset age (L): >51 years old; and not available (NA)); and different forms of PD (sporadic (S)/familial (F)/not reported (NR)). The Q test and I2 statistics for heterogeneity were carried out for each combined analysis where PQ <0.10 or I2 >50% indicated significant heterogeneity. If significant heterogeneity existed, a random-effects model (the DerSimonian and Laird method) was selected to pool the data; otherwise, a fixed-effects model (the Mantel-Haenszel method) was used. When heterogeneity was detected, we performed logistic meta-regression to explore the sources of heterogeneity among studies. The following characteristics were included as covariates in the analysis: genotyping methods (PCR-RFLP/not PCR-RFLP), ethnicity (Caucasian/Asian), quality score (high/low), source of controls , onset age of PD (E/L/NA), and form of the disease (S/F/NR). Galbraith plot analysis was performed for further exploration of the heterogeneity.For the included studies, summary ORs and corresponding 95% CIs were used as a measure to assess the association of P <0.05 was considered a significant publication bias). All data were analyzed using STATA software version 11.0  and all P values were two-sided.To identify possible influential studies, sensitivity analysis was also performed by sequential omission of individual studies, excluding those without definite diagnostic criteria as well as those in which genotype frequencies in control populations exhibited significant deviation from the HWE, given that the deviation may denote bias. HWE in the control group population was tested by using a goodness-of-fit Chisquare test. For each polymorphism, publication bias was evaluated using a funnel plot and Egger’s regression asymmetry test  A vs. G allele ; ii) AA vs. GG ; iii) AG vs. GG ; iv) AG+AA vs. GG ; and v) AA vs. AG+GG . In the subgroup analysis stratified by ethnicity, the results also showed a significant contribution of the CYP2D6*4 allele polymorphism to PD development in the Caucasian population in all of the comparisons of the A vs. G allele ; AA vs. GG ; AG vs. GG ; AG+AA vs. GG ; and AA vs. AG+GG . When stratified by form of the disease, a significantly increased risk was found in all forms of the disease, indicating that susceptibility to PD due to CYP2D6*4 allele polymorphism may be independent from the form of PD onset. Similarly, a significantly increased risk was found only in the “Not available” group when stratified by PD onset age, suggesting that CYP2D6*4 allele mutations are independent from onset age. The details are presented in The pooled analysis suggested that the 2 value of heterogeneity was lower than 50% and the PQ value was lower than 0.10 , indicating a statistically significant heterogeneity among studies. To explore the sources of heterogeneity, we performed meta-regression analyses. The results showed that none of the factors mentioned above were effect modifiers: genotyping methods (P = 0.873), ethnicity (P = 0.853), quality score (P = 0.292), source of controls (P = 0.166), onset age of PD (P = 0.423), and form of the disease (P = 0.948). To further investigate the heterogeneity, Galbraith plots analysis was performed to identify the outliers that might contribute to the heterogeneity. Our results showed that the studies by Kurth et al. [P = 0.001) and was without evidence of heterogeneity  in the overall populations as well as in subgroup analysis of the Caucasian population . However, results remained the same in the other subgroup analyses. For the A vs. G comparison model, the Ih et al.  and Atkih et al.  were theFor the remaining comparison models, there was no statistically significant heterogeneity in the overall population. However, subgroup analysis by onset age and form of the disease indicated significant heterogeneity in the AG vs. GG and AG+AA vs. GG models. When the Galbraith plot was analyzed, the study by Atkinson et al.  was idenAs the genotype frequencies of the control group in 4 studies deviated significantly from HWE ,23,25,32Begg’s funnel plot and Egger’s test were performed to assess the publication bias of articles in all comparison models. The shape of the funnel plots were symmetrical, suggesting that there was no evidence of publication bias among the studies. Egger’s test was also used to statistically assess the funnel plot symmetry. The results still did not suggest any evidence of publication bias in all comparison models .CYP2D6 is a member of the cytochrome P450 gene family, which plays an important role in the metabolism of many substances [CYP2D6 is expressed constitutively in human liver and metabolizes a variety of therapeutic drugs, including antiarrhythmics, antidepressants, and neuroleptics [CYP2D6 can metabolize environmental toxins such as the neurotoxins 1,2,3,4-tetrahydroisoquinoline and MPTP has also been found [CYP2D6 gene is a G to A shift in exon4, which results in substitution of Glu for Gly [CYP2D6 activity. Decreased CYP2D6 activity may lead to an alteration of susceptibility to neurotoxic damage and a higher rate of neuronal loss, thus making carriers more susceptible to PD; this hypothesis was confirmed by the present meta-analysis.bstances . It has oleptics . Evidencen found ,38. A co for Gly , and is CYP2D6*4A allele in the overall population and in Caucasians in particular, suggesting that individuals with the mutated CYP2D6*4 genotype had higher risk of PD compared to those with wild type, especially among the Caucasian population. However, no association was detected among the Asian population. Indeed, it is common for the same polymorphism to play different roles in disease susceptibility among different ethnic populations. This may be principally explained by the CYP2D6 genetic background difference between such populations [CYP2D6*4G/A mutation, but in the original population studied, the mutation was only detected in one individual [CYP2D6 genotype and the risk of developing PD vary between ethnic groups [In our study, a significantly increased risk of PD was associated with the ulations ; using adividual . Furtherc groups . FinallyCYP2D6*4 polymorphism leading to poor debrisoquine metabolism is associated with an increased risk for PD regardless of the patient’s family history. However, there is considerable variation in the frequencies of mutant CYP2D6 alleles in familial and sporadic PD of different populations [CYP2D6 mutations and familial PD [In the subgroup analysis based on form of the disease, a significantly increased risk was found for all forms of the disease , suggesting that the presence of ulations ,22,42,43ilial PD ,22,32,34In a further subgroup analysis restricted to the onset age of PD patients, no significant increased risk was found in patients with early or late onset age, suggesting that the early-onset PD patients share the same genetic background as the late-onset PD patients and there might be not any different pathogenetic mechanisms involved in onset age of PD patients. It has been reported that the frequency of *4 allele is significantly elevated in late-onset as compared with early-onset PD, but similar trend was also found in non-PD populations . TherefoCYP2D6 phenotypes were not studied. Genetic polymorphism of CYP2D6 is inherited as an autosomal recessive trait, with more than 60 alleles known thus far . These alleles, occurring in various combinations or along with other alleles, result in three phenotypes: extensive metabolizer, intermediate metabolizer, and poor metabolizer [CYP2D6, can comprehensively and directly access the relationship between CYP2D6 polymorphism and PD risk. Second, the overall outcomes of our study were based on individual unadjusted ORs, but a more precise evaluation should be adjusted by potentially suspected factors such as age, gender, and environmental factors. Such a problem was observed in a meta-analysis conducted by Rostami et al. [CYP2D6*4 polymorphism in the Asian population included in this study was relatively small, which may lead to low statistical power. Finally, publication bias was possible as no attempts were made to identify unpublished studies, though results of our Begg’s funnel plot and Egger’s test revealed no evidence of publication bias in all comparison models.This meta-analysis should be considered with its limitations. First, the abolizer ,45. Detei et al. , where ai et al. ,24. HencCYP2D6*4G/A polymorphism denotes an increased genetic susceptibility to PD in the overall population, but particularly in Caucasians. However, larger sample studies with a more rigorous design and well-matched controls are required to overcome the above-mentioned limitations, especially investigations taking the other allele polymorphisms of CYP2D6 as well as phenotype status into consideration.In conclusion, the present meta-analysis clearly indicates that the Table S1Check list.(DOC)Click here for additional data file.Table S2Scale for quality assessment.(DOC)Click here for additional data file.


However, the role of PPARα intronic polymorphism with CAD has received little attention. The association of allelic variants G/C at intron 7 of the PPAR-alpha gene with CAD was examined in a hospital-based Indian population. PPAR genotyping was performed in 110 male patients with CAD and 120 age and ethnically matched healthy males by PCR amplification of the gene followed by restriction digestion. Presence of C allele showed a positive association with CAD  and also with dyslipidaemia ; P < .05). Impaired lipid metabolism in carriers of the PPARα Intron 7C allele is possibly responsible for the predilection to CAD. The allelic variants of peroxisome proliferator-activated receptor alpha (PPAR PPARα is also involved in other biological processes, including the regulation of inflammatory and oxidative pathways [The peroxisome proliferator-activated receptors (PPARs) are part of a superfamily of ligand-activated transcription factors involved in fatty acid oxidation and lipid metabolism. PPARpathways .α in cardiovascular disease is an interesting area for research because of its association with fatty acid oxidation, lipid metabolism, and inflammation. In general, activation of the PPARα, both by natural and synthetic ligands, is considered beneficial for cardiovascular health [α contributes to interindividual variability in lipid levels and cardiac hypertrophy. Jamshidi et al. [α G/C polymorphism influences human left ventricular growth in response to exercise and hypertension. There is only one report on the association between the PPARα G/C polymorphism and cardiovascular disease events. Flavell et al. [α gene and progression of atherosclerosis in a Finnish population. They found that homozygotes of Intron 7C had increased risk of ischemic heart disease and C allele carriers had greater progression of atherosclerosis than did G allele homozygotes. This observation warrants further studies and a better understanding of the role of PPARα gene polymorphism in cardiovascular disease. Therefore, this study was taken up with the objective of examining the association of PPAR-alpha Intron 7 G/C polymorphism (G2528C) with CAD in an Indian population.The role of PPARr health . In an er health  have sugi et al.  demonstrl et al.  had inve2. Unaffected age-matched healthy male relatives of the spouse without any of the cardiovascular risk factors formed the control for comparison. Relatives of the spouse were chosen because they were matched for ethnicity and socioeconomic background. Consent for inclusion in the study was obtained from the subjects. The research protocol was approved by the Ethics Committee of the Institute. All consecutive male patients admitted to the cardiology ward of the Institute, with angiographically confirmed CAD, were enrolled in the study. Exclusion criteria were clinical evidence of congenital abnormalities, valvular disease, chronic renal failure, and malignancies. History of hypertension, diabetes, and dyslipidaemia was obtained from medical records. Subjects were defined as hypertensive if their systolic blood pressure was ≥140 mmHg, if their diastolic blood pressure was ≥90 mmHg, or if they were receiving any antihypertensive treatment . Patientα genotyping was performed in 25 microlitre reaction mix containing 5 microlitre 5x GoTaq buffer, 200 micromole of each dNTP, 1.75 mmol/L MgCl2, 5 pmols of each primer, and 0.5 U GoTaq polymerase. PCR primers used by Jamshidi et al. [Two milliliters of blood was collected in a heparinised tube. Genomic DNA was extracted from the whole blood with the use of the Gene elute: Blood genomic DNA kit (Sigma). Genotyping was carried out by polymerase chain reaction (PCR) and restriction enzyme digestion. PPARi et al.  were adoχ2 test was used as the test of significance for the comparison of genotype and allele frequencies between patients and control. P < .05 was considered statistically significant.Chi-square analysis was carried out to test whether the distribution of PPAR genotypes was in Hardy-Weinberg equilibrium. Odds ratio was calculated as a measure of association of the PPAR alleles with coronary artery disease. Pearson  The study sample included 110 patients and 120 controls. The mean age of the sample was 48.64 ± 11.04 years. As expected, blood pressure, BMI, and history of smoking and familial incidence of heart disease were higher in patients . Among tχ2 = 0.14, P > .05) as well as among patients . The proportion of individuals with GC genotype was higher among patients compared to control  regulates genes involved in lipid metabolism, homeostasis and inflammation, in response to fatty acids, and fibrates, making it a candidate gene for risk of dyslipidaemia, atherosclerosis, and coronary artery disease. Various polymorphic markers that act as candidate genes are related to lipoprotein metabolism and accounts for variations in the level of total serum cholesterol and LDL [α gene is in the noncoding region, studies have indicated its potential biological importance. Due to its location in the intron, the variant itself may not be functional, but it may be in allelic association with a functional variant in a promoter or enhancer element of the PPARα gene that results in reduced PPARα gene expression [α gene expression [α Intron 7C polymorphism with dyslipidaemia in diabetic subjects have shown that variation in the PPARα gene influences total cholesterol, LDL-cholesterol (LDL-C), and HDL-cholesterol (HDL-C) in diabetic patients [α level associated with the presence of C allele may be the determining factor for impaired lipid metabolism, which in turn enhances the risk of CAD.Risk factors commonly associated with CAD were seen in patients . A signienotypes . The rispidaemia . Peroxis and LDL –8. Thougpression . Intron pression . Earlierpatients , 11 and patients . Fibratepatients  and the patients , 15. Redα allelic variants influence the predisposition for CAD in human subjects, probably mediated by modulation of the lipid profile. Variations in the human PPARα gene may be one of the contributory factors in the multifactorial etiology of CAD with carriers of the C allele having a predilection to the disease due to raised serum cholesterol. More extensive epidemiological and genetic studies are needed to understand the relationship between the G/C polymorphism in the PPARα gene and serum lipid levels. It is also envisaged that studies will be carried out in other populations to establish the power of the association and also understand the cause for the reduced response of C allele carriers to fibrate therapy.The study has demonstrated that PPAR


ALDH2*2 allele and diabetic retinopathy (DR).Mitochondrial aldehyde dehydrogenase 2 (ALDH2) detoxifies reactive aldehydes in the micro- and macrovasculature. These substrates, including methylglyoxal and 4-hydroxynonenal formed from glucose and lipids, cause protein carbonylation and mitochondrial dysfunction, forming advanced glycation end products (AGEs). The present study aimed to confirm the association between the inactive ALDH2*1/*2 alleles were determined using a real-time TaqMan allelic discrimination assay. Multivariate-adjusted hazard ratios (HRs) and 95% confidential intervals (CIs) for the cumulative incidence of the development of DR were examined using a Cox proportional hazard model, taking drinking habits and the serum γ-glutamyltransferase (GGT) level into consideration.A retrospective longitudinal analysis was conducted, among 234 Japanese patients with type 2 diabetes mellitus (DM)  who had no DR signs at baseline and were treated for more than half a year. The ALDH2*2 allele was 22.3%. Fifty-two subjects cumulatively developed DR during the follow-up period of 5.5 ± 2.5 years. The ALDH2*2 allele carriers had a significantly higher incidence of DR than the non-carriers . The incidence of DR was significantly higher in the drinkers with the ALDH2*2 allele than in those with the ALDH2*1/*1 genotype , while the incidence of DR in the non-drinkers did not differ significantly between the ALDH2 genotype groups (P > 0.05). The incidence of DR was significantly higher in the ALDH2*2 allele carriers with a high GGT level than in the non-carriers with a high or low GGT level .The frequency of the ALDH2*2 allele and the incidence of DR. These findings provide additional evidence that ALDH2 protects both microvasculature and macrovasculature against reactive aldehydes generated under conditions of sustained oxidative stress, although further investigations in larger cohorts are needed to verify the results.To the best of our knowledge, this is the first report of a significant association between the  Hyperglycemia promotes vascular damage in patients with diabetes mellitus (DM) via multiple mechanisms . The preALDH2 gene that was associated with variations in blood pressure (BP) in East Asians [ALDH2*1 allele was identified as a risk factor for an elevated BP. Conversely, the allele was associated with a reduced risk of coronary artery disease (CAD). These associations are believed to be largely mediated by alcohol consumption, because this variant determines an individual’s tolerance to alcohol by altering the ALDH2 enzymatic activity [ALDH2*1 allele on BP to be balanced by the protective effects of alcohol consumption on the lipid profile, thus resulting in a net reduction in the risk of CAD. We, however, have shown that alcohol consumption, even less than one drink/day, increases the risk of hypertension in Japanese individuals with the inactive ALDH2*2 allele [A recent meta-analysis of genome-wide association studies identified a variant, rs671, in the 2 allele .ALDH2*2 allele and the risk of DR among Japanese subjects with type 2 DM.Based on this information, the present study aimed to confirm that ALDH2 potentially protects the microvasculature and macrovasculature against reactive aldehydes and carbonyl stress, regardless of the etiology ,3-9. We A retrospective longitudinal analysis was conducted, among 234 Japanese patients with type 2 DM  who had no DR signs at baseline and had been treated at the Jinnouchi Clinic, Diabetes Care Center in Kumamoto, Japan, for more than half a year between February 2002 and January 2011. The study protocol was approved by the institutional ethics committee, and written informed consent was obtained from each subject. The study was performed in accordance with the Declaration of Helsinki.DR was diagnosed by a professional ophthalmologist using direct ophthalmoscopy or fundus fluorescein angiography. DR was staged as no retinopathy, nonproliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR) according to the criteria determined at the third national ophthalmology conference held in 1985. The occurrence of DR was defined as having no DR signs in both eyes at baseline and developing NPDR or PDR in either of the eyes during the follow-up period.Height and weight were measured using standard protocols, and the body mass index (BMI) was calculated. Fasting blood samples were analyzed using the standard methods of the Japan Society of Clinical Chemistry. The blood pressure (BP) was measured after the subject rested in a sitting position. Information regarding smoking and alcohol drinking habits was obtained via face-to-face interviews conducted by medical staff members. Based on their alcohol drinking habits, the subjects were categorized as non-drinkers (abstainers) or drinkers . Additionally, the level of serum γ-glutamyltransferase (GGT) was measured and used as a biomarker for alcohol intake ,11.ALDH2*1/*2 alleles were determined using a real-time TaqMan allelic discrimination assay  according to the protocols provided by the manufacturer (assay no. C_11703892_10). All reagents were purchased from Applied Biosystems. To ensure the genotyping quality, we included DNA samples as internal controls, hidden samples of known genotypes and negative controls (water).Genomic DNA was prepared from whole blood using a DNA purification kit . The t-test and Fisher’s exact test were used for comparisons of the continuous and categorical variables, respectively. Multivariate-adjusted hazard ratios (HRs) and 95% confidential intervals (CIs) for the cumulative incidence of DR were examined using a Cox proportional hazard model. In the multivariate model, we included the following variables as covariates: gender, BMI, diabetes duration, hemoglobin A1c (HbA1c), systolic BP and the GGT level. The interactive effect and combined effect between the ALDH2 genotypes and the GGT levels at the baseline on the development of DR were also analyzed using a Cox proportional hazard model. Kaplan-Meier survival curves were used to estimate the DR-free survival according to the ALDH2 genotypes or the combinations of the genotypes and the GGT levels. The GGT levels at the baseline were dichotomized according to the median values for males and females. Factors influencing the GGT level were determined using a univariate linear regression analysis with calculations of the β coefficient. The longitudinal relationship between the incidence of DR and the GGT values during the observation period was also assessed using an autoregressive model based on the generalized estimating equations approach. A P value of < 0.05 was considered to be statistically significant. All statistical analyses were performed using the SPSS software package .The data are presented as the means ± standard deviations or proportions for categorical variables. Student’s ALDH2*2 allele was 22.3%, and that of the ALDH2*1/*1, *1/*2 and *2/*2 genotypes was 61.1%, 33.3% and 5.6%, respectively. The observed genotype frequency distribution was consistent with the Hardy-Weinberg equilibrium. Since the number of subjects with the ALDH2*2/*2 genotype was too small to assess the effects of the genotype on the development of DR, the ALDH2*1/*2 and ALDH2*2/*2 genotypes were combined in the subsequent analysis. The demographic characteristics of the subjects with the ALDH2*1/*1 genotype (non-carriers) and the ALDH2*2 allele carriers at baseline are shown in Additional file ALDH2*2 allele carriers than in the non-carriers. The mean GGT value was significantly higher in the drinkers than in the non-drinkers . The median GGT value was 37 IU/L for the males and 26 IU/L for the females.The frequency of the ALDH2*2 allele carriers exhibited a higher incidence of DR than the non-carriers . A significantly higher incidence of DR among the ALDH2*2 allele carriers than the non-carriers was also observed in the Cox proportional hazard model   with increasing HbA1c (by 1.0%), but it was not influenced by gender, BMI, diabetes duration, systolic BP and high GGT level in all subjects  and a high GGT level appeared to be a potential risk factor  for DR  during the follow-up period, and the incidence of DR was 58.6/1,000 person-years. The ALDH2 genotypes and alcohol intake or the GGT levels were observed (P > 0.05). However, the incidence of DR was significantly higher in the drinkers with the ALDH2*2 allele than in those with the ALDH2*1/*1 genotype , while the incidence of DR in the non-drinkers did not differ significantly between the ALDH2*2 allele carriers and non-carriers. Moreover, the incidence of DR in the ALDH2*2 allele carriers with a high GGT level was significantly higher than that observed in the non-carriers with a high or low GGT level  , but not in the non-carriers . Only two subjects were newly identified to be drinkers, while the remaining subjects did not change their drinking habits during the observation period.The longitudinal changes in the GGT values during the observation period are shown in Table ALDH2*2 allele and the incidence of DR. In this retrospective longitudinal study of Japanese subjects with type 2 DM, an alcohol drinking habit, especially a high serum GGT level further increased the risk of DR in the ALDH2*2 allele carriers; however, these factors did not affect the risk in the non-carriers.To the best of our knowledge, this is the first report of a significant association between the ALDH2*2, is common in East Asians; however, it is very rare in other ethnic groups [in vivo owing to its extremely high Km for coenzyme nicotinamide adenine dinucleotide (NAD+) and a much lower Vmax [The allelic variant at rs671, c groups ,12,13. Twer Vmax . The strwer Vmax ,14. For wer Vmax . Derangewer Vmax ,16. Therwer Vmax ,16. ALDHwer Vmax ,9.ALDH2*2 allele carriers exhibit a marked rise in the level of acetaldehyde in the blood and develop acute cardiovascular reactions, such as facial flushing, tachycardia and orthostatic hypotension, following alcohol consumption [ALDH2*2 allele is the strongest genetic modifier of drinking behavior and reduces the risk of alcohol-related diseases, such as alcoholism, alcohol-related liver cirrhosis, chronic pancreatitis, DM and hypertension [ALDH2*2 allele was a significant risk for DR only in drinkers. Light to moderate alcohol intake is known to reduce the incidence of macrovascular diseases in a U-shaped fashion [+[ALDH2*2 allele carriers than in non-carriers in a dose-dependent manner [ALDH2*2 allele is thus considered to be an independent genetic risk factor for alcohol-related microvascular and macrovascular diseases [ALDH2*2 allele is very rare [ALDH2*1/*1 genotype tended to be at a lower risk for the incidence of DR than non-drinkers (data not shown). These facts suggest that ALDH2 protects the vasculature from reactive aldehydes in relation to the beneficial effects of mild to moderate alcohol intake [sumption . Consequrtension -8,12,17.rtension ,19 and t fashion . Ethanolashion [+. These rashion [+,21. Convdiseases ,6,8. Oneery rare . The prel intake -22.ALDH2*2 allele carriers with a high GGT level at baseline than in the non-carriers with a high or low GGT level (Table ALDH2*2 allele carriers, the frequency of drinkers was comparable between the subjects with high and low GGT levels (Table ALDH2*2 allele carriers (Table We further investigated the data after taking into account the GGT level, a valid marker of excessive alcohol consumption ,23 The oel Table b. The GGrs Table . The patThe crucial limitations of the present study include the retrospective study design and small sample size. In addition, the details of the subjects’ drinking habits, the influence of drug therapy were uncertain.ALDH2*2 allele is an independent risk factor for the incidence of DR. The association between the ALDH2 genotype and the incidence of DR was significant among drinkers and subjects with a high GGT level. These findings provide additional evidence that ALDH2 protects both the microvasculature and macrovasculature against the reactive aldehydes generated under conditions of sustained oxidative stress, although further investigations in larger cohorts are needed to verify the results.In conclusion, we herein demonstrated that the ACE: Angiotensin converting enzyme; ADMA: Asymmetric dimethylarginine; AGE: Advanced glycation end product; ALDH2: Aldehyde dehydrogenase 2; ALT: Alanine aminotransferase; ARB: Angiotensin II receptor blocker; AST: Aspartate aminotransferase; BMI: Body mass index; BP: Blood pressure; CAD: Coronary artery disease; CI: Confidence interval; DDAH1: Dimethylarginine dimethylaminohydrolase 1; DM: Diabetes mellitus; DR: Diabetic retinopathy; GGT: γ-glutamyltransferase; GSH: Glutathione; HbA1c: Hemoglobin A1c; HDL: High-density lipoprotein; 4-HNE: 4-hydroxynonenal; HR: Hazard ratio; LDL: Low-density lipoprotein; NAD: Nicotinamide adenine dinucleotide; NPDR: Nonproliferative diabetic retinopathy; PDR: Proliferative diabetic retinopathy.The authors declare that they have no competing interests.All authors have made substantial contributions to conception and design, or acquisition of data, or analysis and interpretation of data; have been involved in drafting the manuscript or revising it critically for important intellectual content; and have given final approval of version to be published. All authors read and approved the final manuscript.ALDH2 genotype at the baseline. Table S2. Association between the risk for DR and the covariates. Table S3. Clinical characteristics of subjects stratified by drinking habit at the baseline.Clinical characteristics of subjects stratified by the Click here for file


We systematically reviewed etiological factors of Kienböck’s disease (osteonecrosis of the lunate) discussed in the literature in order to examine the justification for including Kienböck’s disease (KD) in the European Listing of Occupational Diseases.We searched the Ovid/Medline and the Cochrane Library for articles discussing the etiology of osteonecrosis of the lunate published since the first description of KD in 1910 and up until July 2012 in English, French or German. Literature was classified by the level of evidence presented, the etiopathological hypothesis discussed, and the author's conclusion about the role of the etiopathological hypothesis. The causal relationship between KD and hand-arm vibration was elucidated by the Bradford Hill criteria.A total of 220 references was found. Of the included 152 articles, 140 (92%) reached the evidence level IV (case series). The four most frequently discussed factors were negative ulnar variance , primary arterial ischemia of the lunate , trauma  and hand-arm vibration . The quality of the cohort studies on hand-arm vibration did not permit a meta-analysis to evaluate the strength of an association to KD. Evidence for the lack of consistency, plausibility and coherence of the 4 most frequently discussed etiopathologies was found. No evidence was found to support any of the nine Bradford Hill criteria for a causal relationship between KD and hand-arm vibration.A systematic review of 220 articles on the etiopathology of KD and the application of the Bradford Hill criteria does not provide sufficient scientific evidence to confirm or refute a causal relationship between KD and hand-arm vibration. This currently suggests that, KD does not comply with the criteria of the International Labour Organization determining occupational diseases. However, research with a higher level of evidence is required to further determine if hand-arm vibration is a risk factor for KD. Kienböck’s disease (KD) is an osteonecrosis involving the lunate bone that finally results in carpal collapse and severe wrist arthrosis. Currently no evidence exists demonstrating a treatment that has the ability to lead to disease regression or even halt disease progression . The numhv=13,5m/s2) resulted in the implementation of further occupational preconditions for vibration-induced KD in Germany in 1998 [2) [Traditionally KD is recognized as an occupational disease caused by hand-arm vibration or by trauma in work-related injuries . Low fre in 1998 . The nec1998 [2) .KD is listed under the number 505.01 in the European Listing of Occupational Diseases in countries such as Germany and France, whereas this is not the case in others such as Austria . DespiteThe analytical framework of Bradford Hill's criteria , represent an important tool for scientifically determining causality between any discussed factors and KD . Yet theThe average percentage of recognized occupational diseases in relation to those suspected is 80% in France and Switzerland, between 40 and 50% in Sweden, Portugal, Austria and Belgium, and under 25% in Germany, Finland and Italy . This loA systematic review was conducted using the Ovid/Medline and the Cochrane database for the keywords “Kienböck's disease” and “etiology” including different spellings and synonyms . Non-systematic reviews of the scientific literature were classified as expert opinions. Predisposing, risk and causative factors were categorized according to the author's judgment if they were either likely or unlikely linked to the etiology of KD while factors interpreted as mere coincidences (e.g. confounding factors) and previously unreported in the literature as being causative were not documented. Studies which found no significant results regarding the association of any of the discussed factors, or articles arguing against an etiologic role of certain factors, were defined as null studies. Since technical terms have changed over the large period of time encompassed by the study and since no clear distinction has been made along the reviewed literature, repeated microtrauma, repetitive loading, repetitive strain, cumulative trauma and hand-arm vibration were considered synonyms.Among the total of 215 full-text articles, 153 articles were included in the systematic review and screened for the discussed etiopathological factors of KD , which are widely accepted in epidemiology for investigating and defining causality and have been adopted by the International Labour Organization ,10,16. TThe four most frequently discussed hypotheses, negative ulnar variance , primary arterial ischemia of the lunate , trauma  and hand-arm vibration , were discussed in 124 of the 153 included articles  supported or suggested a causal relationship between KD and exposure to hand-arm vibration. Among these were five anatomical studies, 9 expert opinions, 22 case reports, 12 case series, one case control study and 4 cohort studies. Further, 16 studies were identified that argued against an etiopathologic role of hand-arm vibration  among chain-saw workers and no KD in any of the control groups (0/753) (Fisher's Exact Test p=0.017)  . The numThe finding that only 35% of published literature on the etiopathology of KD favours a causal relationship between KD and hand-arm vibration, underlines the lack of scientific consensus. On the other hand, null studies regarding the association between KD and hand-arm vibration represent 10% of published literature and 23% of all articles discussing an etiopathologic role of hand-arm vibration. Four out of 7 cohort studies on the influence of hand-arm vibration conclude that there is no association. Among the 4 controlled cohort studies 2 conclude that there is no association , hand-arm vibration ) have increasingly been replaced by other hypotheses. With regard to the popularity of the discussed etiopathological hypotheses of KD, surprisingly it was found that hand-arm vibration has not been discussed in much frequency since 1950 Figure .The hypothesis of a multifactorial genesis of KD has often been brought forward since 1936 -23, appaTo establish a causal relationship, the effect must occur after the cause . OccasioSince a significant association between KD and hand-arm vibration is a prerequisite to determine a biological gradient, a biological gradient regarding the effect the vibration magnitude, frequency, direction, type of tools, duration and pattern of exposure or any other extrinsic or intrinsic conditions has not been validly documented for KD.Contrary to expert or to historical opinion, that “the lunate bone is the hand’s only cushion against impacts on the wrist” , biomechExposure to low frequency vibrations has been claimed to induce inflammatory mediators that “lead to the liberation of cytolytic enzymes, disturbing the balance between cartilage removing and cartilage forming processes and thereby accelerating the degeneration of cartilage” . To our The German occupational disease ordinance further refers to an anatomical study from 1944 in which a mercury solution was injected into the brachial artery in neutral position with the wrist extended, observing that the lunate remained void of mercury during extension of the wrist . The aut2 , which does present a potential health risk [According to official epidemiologic data 1.2 million Germans are exposed to a daily vibration level greater than A(8)=2,5m/slth risk . On the lth risk . In the lth risk . Since elth risk , (IV) haThe vast majority of authors describe a rich and constant palmar and dorsal vascularization of the lunate bone  which evRegarding the hypothesis of trauma, Wette notes “that uncomplicated reductions of lunate dislocation never display signs of osteonecrosis, not even in cases where the lunate had not been reduced (…) severe and direct wrist strain, leading to intra-articular distal radius fracture and to fractures of the perilunar carpal bones (…) never caused late secondary lesions of the lunate bone (…) Since we have never seen such cases of theoretically possible occurrences among our patients, we must as experts defend the point of view that the fracture theory is a hypothesis for which direct evidence is lacking” . Case reThe ability of bone to respond to mechanical stimuli has been known for over a century. Moreover we now know that (I) bone preferentially responds to dynamic rather than static stimuli, (II) only short durations of loading are necessary to initiate an adaptive response, and (III) bone cells accommodate to customary mechanical loading environments . Daily ehv(8) 5m/s2, 220 exposure days per year) the risk of exceeding the vibration magnitude is 5 times less compared to the exposure to jackhammers in the 1930s [According to Hill, the decreasing incidence of lung cancer in a population that stops smoking adds to the evidence of a causal relationship. By today's occupational safety and health guidelines  the level of evidence presented ; 2) the predisposing factors, risk factors and etiopathological hypotheses of KD discussed per article ; and 3) the author's judgment if the discussed factors and hypotheses were maybe or unlikely linked to the etiology of KD . The high inter-rater agreement supports the reliability of the approach. On the other hand the attribution of explicit but also broad criteria  might have led to an overestimation of consistency because of a tendency of authors to echo pre-existing hypotheses.”Our study had several limitations, most of which are inherent to any systematic review and meta-analysis of literature. Publication bias may distort meta-analysis because editors, reviewers or researchers may not want to challenge prevailing paradigms -51. The Arbitrary, technical requirements and the exposure limit value as well as expert and historical opinions and hypothesis make it difficult to determine a causal relationship between KD and hand-arm vibration.Limited evidence was found to sustain that hand-arm vibration represent a predisposing risk or causative factor for KD. Independent of the significance, correlations do not suffice to determine causality. Despite certain limitations, several of Bradford Hill’s criteria when taken together do contribute to a more comprehensive causal theory . The sumThe negative impact of speculative causal associations . The numbers at the bottom represent the sum of articles supporting or acknowledging the discussed hypotheses.Click here for file


Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) plays an important role in the pathophysiology of atherosclerosis and thrombosis. This study is aimed at evaluating the potential association of 3’-UTR-C188T and G501C in LOX-1 gene with cerebral infarction.A total of 386 patients with cerebral infarction and 386 healthy controls were included in the study, which were unrelated Chinese Han population in the Liaoning Province of northern China. The single nucleotide polymorphisms, 3’-UTR-C188T and G501C, were analyzed by polymerase chain reaction–ligation detection reaction method.P < 0.01, P < 0.01, P = 0.04, respectively). The correlation still remained after adjusting for confounding risk factors of cerebral infarction. In addition, no significant association was observed between 3’-UTR-C188T and cerebral infarction.The frequencies of CC + GC genotype, GC genotype and C allele of G501C in the patients with cerebral infarction were significantly higher than those in the controls (The study indicated that the G501C variant in LOX-1 gene may be associated with susceptibility to cerebral infarction, independent of other common risk factors, in northern Chinese Han population. Stroke is the second most common cause of death and the leading cause of long-term disability worldwide. In ChinLectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a trans-membrane glycoprotein which belongs to a class E scavenger receptor and mediates the uptake and internalization of ox-LDL (oxidized low-density lipoprotein). Recent Therefore, in the present study, we investigated the association of these two LOX-1 gene polymorphisms  with cerebral infarction in Chinese Han population.A total of 386 cerebral infarction patients and 386 healthy controls were enrolled in this study. The characteristics of the patients and controls are shown in Table P was 0.14 and 0.86 for the patient and control groups, respectively; while for G501C, P was 0.17 and 0.09 for the patient and control groups, respectively. As shown in Tables P < 0.01). The GC genotype (35.0%) of G501C was represented at an increased frequency in the group of patients . The frequency of G501C C allele was significantly higher in patients with cerebral infarction than in the control group .The genotype and allele frequencies of two LOX-1 gene polymorphisms in patients and control subjects were shown in Tables P < 0.01),as well as other conventional risk factors . In order to evaluate the goodness-of-fit of the model, we have used the Hosmer-Lemeshow test. The model correctly predicted 61.7% of the cases and the Hosmer-Lemeshow goodness-of-fit test demonstrated that the calibration of the model was satisfactory .Binary logistic regression with backward stepwise method was used to evaluate the association between G501C polymorphism in LOX-1 gene and the risk of cerebral infarction in the dominant model. As shown in Table This study investigated the association between LOX-1 gene polymorphisms, 3’-UTR-C188T and G501C, and cerebral infarction in northern Chinese Han population. In this study, we found that the genotypic and allelic frequencies of G501C were significantly associated with the increased risk of cerebral infarction. However, no association of 3’-UTR-C188T with the risk of cerebral infarction was found.The 3’-UTR-188 T variant may have effects on transcription at the gene level and affect the exon splicing or the binding affinity of a putative regulatory element. TherefoP = 0.48, P = 0.91). However, in this study, we found that the CC + GC genotype, the GC genotype and C allele of G501C were significantly associated with the increased risk of cerebral infarction in Chinese Han population. After adjusting for the confounding risk factors, this significant correlation still remained. There are two potential explanations for the divergent results. Genetic heterogeneity may be the important reason. Genotype frequencies of the G501C in our control subjects  are different from those in Japanese population . In addition, the relative small sample size of Hattori’s study, consisting of 235 patients with cerebral infarction and 274 controls, might be more likely to get false negative results.As for G501C variant in LOX-1 gene, its association with cardiovascular disease is also quite contradictory. Tatsuguchi et al. found thHow can we explain the association between G501C in LOX-1 gene and cerebral infarction in Chinese population? 1) LOX-1 is involved in endothelial activation and dysfunction, monocyte adhesion, the proliferation, migration, and apoptosis of smooth muscle cells, foam cell formation, plaque instability, as well as platelet activation; all of these events are critical in the pathogenesis of atherosclerosis and thrombosis,21. 2) TIn summary, our study demonstrated that G501C, but not 3’-UTR-C188T, in LOX-1 gene may be associated with susceptibility to cerebral infarction, independent of other common risk factors, in northern Chinese Han population. However, the present study also has some limitations, such as the relative small sample size. Therefore, well-designed studies with large sample sizes regarding the association of LOX-1 gene polymorphisms with cerebral infarction on different ethnic population will be needed to verify these findings in the future.The present study included 386 cerebral infarction patients and 386 healthy controls, which were unrelated Chinese Han population in the Liaoning Province of northern China. The patients were consecutively hospitalized in the Department of Neurology, the First Affiliated Hospital of China Medical University between September 2011 and December 2012. Eligible patients were defined as those who were first diagnosed with acute cerebral infarction according to neurological examination and radiological imaging. According to TOAST classification, cerebral infarction can be divided into five subtypes: 1) large-artery atherosclerosis (LAA), 2) small-vessel occlusion (SVO), 3) cardioembolism (CE), 4) stroke of other determined etiology, and 5) stroke of undetermined etiology. PatientClinical records of patients and controls, including the general condition, past history, blood pressure, fasting blood glucose, serum triglyceride, and total cholesterol, were collected. For patients, brain CT or MRI, echocardiography, carotid ultrasound, transcranial Doppler, and electrocardiogram were also required. Hyperlipidemia was defined as a total plasma cholesterol level >5.72 mmol/L and/or plasma triglycerides level >1.7 mmol/L, or current use of lipid-lowering drugs.2+ , 0.3 mM dNTP , 1 U HotStarTaq polymerase , 1 μL each primers  and 1 μL genomic DNA. The PCR cycling program was set at 95°C for 2 min, followed by 11 cycles of 94°C for 20 s, 65°C (decreased 0.5°C per cycle) for 40 s, 72°C for 1.5 min, and then 24 cycles of 94°C for 20 s, 59°C for 30 s, and 72°C for 1.5 min, and a final extension at 72°C for 2 min. Then shrimp alkaline phosphatase  and Exonuclease I  were added into the PCR products for purification. The probes for LDR are shown in Table 2O. The LDR reactions were cycled as: 38 cycles of 94°C for 60 s and 56°C for 4 min, and kept at 4°C. After the reaction, 0.5 μL LDR product was then sequenced with ABI3730XL sequencer . Finally the raw data was analyzed by GeneMapper 4.1 .Genomic DNA was extracted from EDTA-anticoagulated peripheral blood by a DNA Purification Kit . Genotypings were determined using the polymerase chain reaction-ligation detection reaction (PCR-LDR) method. DNA purt or Mann–Whitney U test, depending on the shape of the distribution curves. Categorical variables were compared by χ2 test. Differences of the distributions of alleles and genotypes between cases and controls were analyzed using χ2 test. All genotype frequencies were checked for Hardy-Weinberg analysis in two groups through χ2 test[P value of 0.05 was considered statistically significant for all statistical analyses. All the statistical analyses were carried out using SPSS version 17.0 .Continuous variables were presented as mean ± SD and categorical variables as percentages. Normality of the sample distribution of each continuous variable was tested with the Kolmogorov-Smirnov test. Differences of continuous variables were evaluated by the Student's  χ2 test. The assLOX-1: Lectin-like oxidized low-density lipoprotein receptor-1; ox-LDL: Oxidized low-density lipoprotein; PCR-LDR: Polymerase chain reaction-ligation detection reaction; OR: Odds ratio; CI: Confidence interval; BMI: Body mass index.The authors declare that they have no competing interests.XL carried out the molecular genetic studies and drafted the manuscript. XL and RXZ carried out the genotyping. XL and LL participated in the design of the study and performed the statistical analysis. ZYH and XL conceived of the study, and participated in its design and coordination. ZYH helped to draft the manuscript. All authors read and approved the final manuscript.


Significant results were also observed using dominant , recessive  and co-dominant genetic model . There was strong evidence of heterogeneity, which largely disappeared after stratification by ethnicity. Significant associations were found in East Asians, and White populations when stratified by ethnicity; while no significant associations were observed in Africans and other ethnic populations. An association was observed for both ER-positive  and ER-negative disease  and both progesterone receptor (PR)-positive  and PR-negative disease . In conclusion, this meta-analysis demonstrated that the A allele of 2q35-rs13387042 is a risk factor associated with increased breast cancer susceptibility.Genome-wide association studies have identified 2q35-rs13387042 as a new breast cancer (BC) susceptibility locus in populations of European descent. Since then, the relationship between 2q35-rs13387042 and breast cancer has been reported in various ethnic groups; however, these studies have yielded inconsistent results. To investigate this inconsistency, we performed a meta-analysis of 26 studies involving a total of 101,529 cases and 167,363 controls for 2q35-rs13387042 polymorphism to evaluate its effect on genetic susceptibility for breast cancer. An overall random effects odds ratio of 1.14 (95% CI: 1.11–1.16, P<10 Breast cancer is the most common cancer and the leading cause of cancer death among women worldwide, accounting for 23% of the total cancer cases and 14% of the cancer deaths in 2008 Papers published before the end of January 2013 were identified through a search of Pubmed, SCOPUS, ISI web of knowledge, Embase and Cochrane databases Search term combinations were keywords relating to the chromosome 2q35  in combination with words related to breast cancer  and polymorphism or variation. The titles and abstracts of potential articles were screened to determine their relevance, and any clearly irrelevant studies were excluded. The full texts of the remaining articles were read to determine whether they contained information on the topic of interest. In addition, all reference lists from the main reports and relevant reviews were hand searched for additional eligible studies not indexed by Medline.P-value, (4) genotype distribution of control group must be consistent with Hardy–Weinberg equilibrium (HWE).Eligible studies had to meet all of the following criteria: (1) original papers containing independent data which have been published in peer-reviewed journal, (2) case–control or cohort studies, (3) genotype distribution information or odds ratio (OR) with its 95% confidence interval (CI) and For each qualified study, the following information was extracted independently and entered into separate databases by two authors: first author's surname, publication date, ethnicity, source of control subjects, genotyping method, age, tumor stage, histopathological subtype, ER status, PR status, total number of cases and controls, and genotype frequency in cases and controls. The results were compared, and disagreements were discussed among all authors and resolved with consensus. For studies including subjects of different ethnic groups, data were extracted separately according to ethnicity. If multiple published reports from the same study population were available, we included only the one with largest sample size and the most detailed information. Meanwhile, different case–control groups in one study were considered as independent studies.The meta-analysis examined the association between the rs13387042 polymorphism and the risk of BC, for the: (i) allele contrast, (ii) dominant, (iii) recessive, and (iv) co-dominant models The combined search yielded 113 references. 87 articles were excluded because they clearly did not meet the criteria or overlapping references . FinallyThere was a wide variation in the A allele frequency of the rs13387042 polymorphism among the controls across different ethnicities, ranging from 0.05 to 0.75 . For Eas−5, P(Q)<10−5; −5, P(Q) = 0.11] and 1.17 . Significant associations were also found for co-dominant genetic model . In the stratified analysis by ethnicity, significantly increased risks were found among East Asians  and White populations . However, no significant associations were detected among African  and other ethnic populations . Subsidiary analyses of study design yielded a per-allele OR for GWAS of 1.16  and for candidate gene study of 1.11 .The main results of this meta-analysis were listed in −5; P(Q) = 0.47] than ER-negative tumors   = 0.57] compared with PR-negative tumors   case subjects with ER-negative (ER−) case subjects, and in a similar fashion progesterone receptor-positive (PR+) case subjects with receptor–negative (PR−) case subjects. Stratification of tumors by ER status indicated that rs13387042 had a stronger association with ER-positive  . Similar = 0.16] .−5; P(Q) = 0.27] as compared to invasive cancer .The effect of the polymorphism was assessed for over-all breast cancer risk. No association was established between the polymorphism and tumor invasiveness. The data on tumor invasiveness were available in three studies, which included 20442 breast cancer patients. For 2q35-rs13387042, there appeared to be a similar per-allele OR for in situ cancer [per-allele OR = 1.17, 95% CI: 1.04–1.13; P(Z)<10Significant heterogeneity was present among the 44 data sets from 26 studies of the rs13387042 polymorphism (P<0.05). In meta-regression analysis, sample size (P = 0.21), source of controls (P = 0.15) and genotyping method (P = 0.73) did not significantly explain such heterogeneity. By contrast, ethnicity (P = 0.004) was significantly correlated with the magnitude of the genetic effect.Influence analysis was performed to assess the influence of each individual study on the pooled OR by sequential removal of individual studies. The results suggested that no individual study significantly affected the pooled OR, thus suggesting that the results of this meta-analysis are stable (data not shown). The shape of the funnel plot did not indicate any evidence of obvious asymmetry , thus suGWAS have led to the identification of multiple new genetic variants associated with breast cancer risk. Most of these breast cancer GWAS and replication studies have been conducted in European populations Our results demonstrated that the A allele of the 2q35-rs13387042 polymorphism is a risk factor for developing breast cancer. In the stratified analysis by ethnicity, significant associations were found in East Asians and Whites for the polymorphism in all genetic models. However, no significant associations were detected among African and other ethnic populations. There are some points should be concerned for such inconsistent results. Firstly, ethnic differences may attribute to these different results, since the distributions of the 2q35-rs13387042 polymorphism were different between various ethnic populations. For instance, the frequencies of risk-A allele differs from 6% in Chinese population The original publication on 2q35-rs13387042 A number of factors predict breast cancer, however, detailed pathogenesis mechanisms of breast cancer remain a matter of speculation. 2q35-rs13387042 is located in a 90-kb region of high linkage disequilibrium that contains neither known genes nor non coding RNAs Compared with the previous meta-analysis Limitations also inevitably existed in this meta-analysis. First, our meta-analysis is based on unadjusted estimates, whereas a more precise analysis could be performed if individual data were available, which would allow for an adjustment estimate. To be made, however, this approach requires the authors of all of the published studies to share their data. Second, no statistically significant association between the polymorphism and breast cancer appeared in other ethnic populations in racial subgroup analysis. However, the other ethnic population reports in the subgroup analysis include a mixture of populations from very distant countries, so the result must be interpreted with caution. Finally, the subgroup meta-analyses considering interactions between rs13387042 polymorphism and hormone receptor status, as well as tumor invasiveness were performed on the basis of a fraction of all the possible data to be pooled, so selection bias may have occurred and our results may be overinflated. Nevertheless, the total number of subjects included in this part of the analysis comprises the largest sample size so far.Despite these limitations, this meta-analysis suggests that 2q35-rs13387042 polymorphism was significantly associated with increased risk of breast cancer, particularly in East Asian and white populations. As studies among other ethnic populations are currently limited, further studies including a wider spectrum of subjects to investigate the role of this variant in other populations will be needed.Figure S1Flow chart of literature search.(TIF)Click here for additional data file.Figure S2Begg's funnel plot of 2q35-rs13387042 polymorphism and breast cancer risk .(TIF)Click here for additional data file.Table S1Meta-analysis of the 2q35-rs13387042 polymorphism on breast cancer risk using co-dominant model.(DOCX)Click here for additional data file.Checklist S1PRISMA 2009 Checklist.(DOC)Click here for additional data file.


NRGN is a genetic risk variant with genome-wide significance for schizophrenia. The frequency of the T allele of rs12807809 is higher in individuals with schizophrenia than in those without the disorder. Reduced immunoreactivity of NRGN, which is expressed exclusively in the brain, has been observed in Brodmann areas (BA) 9 and 32 of the prefrontal cortex in postmortem brains from patients with schizophrenia compared with those in controls.The rs12807809 single-nucleotide polymorphism in Genotype effects of rs12807809 were investigated on gray matter (GM) and white matter (WM) volumes using magnetic resonance imaging (MRI) with a voxel-based morphometry (VBM) technique in a sample of 99 Japanese patients with schizophrenia and 263 healthy controls.NRGN genotype on GM volume of patients with schizophrenia and healthy controls were separately investigated. In patients with schizophrenia, carriers of the risk T allele had a smaller GM volume in the left ACC (BA32) than did carriers of the non-risk C allele. Significant genotype effect on other regions of the GM or WM was not observed for either the patients or controls.Although significant genotype-diagnosis interaction either on GM or WM volume was not observed, there was a trend of genotype-diagnosis interaction on GM volume in the left anterior cingulate cortex (ACC). Thus, the effects of NRGN gene may be related to a small GM volume in the ACC in the left hemisphere in patients with schizophrenia.Our findings suggest that the genome-wide associated genetic risk variant in the  Schizophrenia is a common and complex psychiatric disorder that has a strong genetic component; the estimated heritability is 81% p values smaller than the genome-wide significance threshold of approximately 1.6×10−7 in the combined samples. Five of these markers—rs6913660, rs13219354, rs6932590, rs13211507 and rs3131296—span the major histocompatibility complex (MHC) region on chromosome 6p21.3–22.1; one marker, rs12807809, is located 3,457 bases upstream from the neurogranin (NRGN) gene on 11q24.2; one additional marker, rs9960767, is located in intron four of the transcription factor 4 (TCF4) gene on 18q21.2. Of these seven SNPs, four SNPs, rs6913660, rs13219354, rs13211507 and rs9960767, were not polymorphic in samples from the HapMap Japanese in Tokyo (JPT) project. Minor allele frequencies (MAF) of two SNPs, rs6932590 and rs3131296, were under 5%. Because only one marker, rs12807809 in NRGN, was a common SNP in HapMap JPT samples (MAF>5%), we focused on this SNP in the present study.A genome-wide association study (GWAS) of single-nucleotide polymorphisms (SNPs) conducted by accessing thousands of DNA samples from patients and controls can be a powerful tool for identifying common risk factors for such a complex disease. Stefansson et al. examined a combined sample of 12,945 patients with schizophrenia and 34,591 controls from three large GWASs  and a follow-up with 4,999 patients and 15,555 controls from four additional sample sets from various areas of Europe  NRGN is the human homolog of the neuron-specific rat gene RC3/neurogranin. NRGN encodes a postsynaptic protein kinase substrate that binds to calmodulin (CaM) in the absence of calcium NRGN gene spans 7.3 kb of genomic DNA and contains four exons that transcribe a protein of 78 amino acids 2+–CaM signaling pathway 2+ influx-induced oxidation of NRGN leads to postsynaptic activation of CaM-dependent protein kinase II (CaMKII) by CaM, which is associated with strengthened N-methyl-d-aspartate (NMDA) receptor signaling COMT, DISC1, PACAP, BDNF, APOE and AKT1) TBP and SIGMAR1) in psychiatric disorders NRGN is expressed exclusively in the brain, especially in the dendritic spines. Reduced NRGN immunoreactivity has been observed in prefrontal areas 9 and 32 of post-mortem schizophrenic brains NRGN polymorphism and the genotype-diagnosis interaction on brain morphology at the whole brain level. In this study, we examined the impacts of the NRGN polymorphism and the genotype-diagnosis interaction on GM volumes and WM volumes in patients with schizophrenia and in healthy volunteers.Many attempts have been made to minimize clinical and genetic heterogeneity in studies of schizophrenia. One strategy for gene discovery uses neurobiological quantitative traits (QT) as intermediate phenotypes rather than the diagnosis of schizophrenia Written informed consent was obtained from all subjects after the procedures had been fully explained. This study was carried out in accordance with the World Medical Association's Declaration of Helsinki and approved by the Research Ethical Committee of Osaka University.Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) based on the Structured Clinical Interview for DSM-IV (SCID). Controls were recruited through local advertisements at Osaka University. Psychiatrically, medically and neurologically healthy controls were evaluated using the non-patient version of the SCID to exclude individuals who had current or past contact with psychiatric services or who had received psychiatric medication. Current symptoms of schizophrenia were evaluated using the positive and negative syndrome scale (PANSS) p>0.17), while the years of education, estimated premorbid intelligence quotient (IQ) and GM volumes were significantly lower in the patients with schizophrenia than in the controls (p<0.001) (Voxel-based morphometry (VBM) analyses were conducted on 99 patients with schizophrenia  and 263 healthy controls . All subjects were biologically unrelated within the second-degree of relationship and of Japanese descent p<0.001) . When thp<0.001) .NRGN gene as described in the introduction. This polymorphism is reported as T/C and was previously described in the GWAS p>0.05).We selected rs12807809 in the http://dbm.neuro.uni-jena.de/vbm/vbm5-for-spm5/manual/) and as previously described All magnetic resonance (MR) studies were performed on a 1.5T GE Sigma EXCITE system. A three-dimensional volumetric acquisition of a T1-weighted gradient echo sequence produced a gapless series of 124 sagittal sections using a spoiled gradient recalled acquisition in the steady state (SPGR) sequence . MR images were processed using optimized VBM in Statistical Parametric Mapping 5 (SPM5) running on MATLAB R2010b  according to the VBM5.1-Manual (http://www.fil.ion.ucl.ac.uk/spm/software/spm8/). First, we performed whole brain searches to explore the effects of the NRGN genotype and the genotype-diagnosis interaction on GM or WM volume in total subjects. Second, we performed separate whole brain searches to explore the effect of the NRGN genotype on GM or WM volume in patients with schizophrenia and in controls. The genotype effect on GM or WM volume was assessed statistically using a multiple regression model in SPM8. We contrasted GM or WM volume between the genotype groups ; GM or WM volumes were correlated with the number of risk T alleles, either positively (CC<CT<TT) or negatively (TT<CT<CC). The genotype-diagnosis interaction on GM or WM volumes was assessed full factorial model with diagnosis as a factor and genotype status as a covariate interacted with the diagnosis in SPM8. Age, sex and years of education were included as covariates of no interest into all analyses to control for confounding variables. Non-sphericity was estimated. These analyses yielded statistical parametric maps {SPM (t)} based on a voxel-level height threshold of p<0.001 (uncorrected for multiple comparisons). Clusters of more than 100 contiguous voxels were considered in the analyses. Family-wise error (FWE) correction was applied for multiple testing to avoid type I errors. The significance level was set at p<0.05 (FWE corrected). Anatomic localization was performed according to both MNI coordinates and Talairach coordinates, which were obtained from M. Brett's transformations (http://www.mrccbu.cam.ac.uk/Imaging/Common/mnispace.shtml) and presented as Talairach coordinates.Statistical analyses were performed with SPM8 software . Statistical analyses of demographic variables were performed using PASW Statistics 18.0 software . Differences in clinical characteristics between patients and controls or between genotypes were analyzed using 2χ tests for categorical variables and the Mann-Whitney U-test or Kruskal-Wallis test for continuous variables. The significance level for all statistical tests was set at two-tailed p<0.05.The presence of Hardy-Weinberg equilibrium was examined by the p<0.001, p<0.001, p<0.001, FWE-correction for multiple tests (FWE-corrected p>0.05). There was no significant effect of the risk T allele on increased GM volumes, the risk T allele on decreased WM volumes, or genotype-diagnosis interaction on WM volume among total subjects (uncorrected p>0.001).First, we investigated the effects of genotype and diagnosis-genotype interaction on GM or WM volumes in the whole brain analyses of total subjects. We found significant effects of the risk T allele on decreased GM volume in the right fusiform gyrus . In patients with schizophrenia, the risk T carriers had a smaller GM volume in the left anterior cingulate gyrus than did the non-risk C carriers .Researchers have suggested that the volume reduction of the anterior cingulate cortex (ACC) is associated with the duration of the illness (the length of time the patient has had schizophrenia) NRGN genotype on GM volume in the bilateral precuneus among the patients with schizophrenia . There was no significant effect of the NRGN genotype on GM volume among the healthy controls (uncorrected p>0.001).We found significant effects of the p<0.001). On the other hand, we found significant effects of the risk T allele on increased WM region (CC<CT<TT) in the bilateral insula and middle frontal gyrus among the patients with schizophrenia . There was no significant genotype effect on any increased WM region for the controls (uncorrected p<0.001). These findings suggest that NRGN may not play a major role in the morphology of WM.We found no significant effect of the risk T allele on any decreased WM regions (TT<CT<CC) for either the patients or controls . The regions shown in the Supporting Information (uncorrected p<0.001) might be helpful in further studies. It is still unclear whether this genetic variant of the NRGN gene is associated with the expression, transcription, splicing or translation of the gene. The lack of a clear association makes it difficult to determine whether our results are directly linked to the NRGN polymorphism rs12807809, to other polymorphisms in linkage disequilibrium with this variant, or to interaction between this genetic variant of the NRGN and other polymorphism. As with other risk variants for schizophrenia, clarifying the biological role of this variant through in vitro and in vivo studies is important to improve the understanding of the pathophysiology of schizophrenia. In addition, an extensive search for other functional variants at this locus is needed to determine whether rs12807809 is the most strongly associated variant for schizophrenia in this gene.There were several limitations to this study. A false-positive association could not be excluded from our study despite the precautions for ethnic matching and corrections for multiple testing. It is necessary to conduct further investigations to confirm our findings in other samples with much larger sample sizes and/or with different ethnicities and/or in relatives with schizophrenia. A false-negative association could not be excluded in our study because we applied a strict correction for multiple comparisons at the whole brain level  in the patients with schizophrenia was shown by hot colormap (red areas), while effect of the T allele on decreased GM regions in the healthy controls was shown by winter colormap (blue areas).(TIF)Click here for additional data file.Figure S2Effect of the risk-T-allele on increased GM regions in the patients with schizophrenia. Effect of the risk T allele on increased GM regions (CC<CT<TT) in the patients with schizophrenia was shown by hot colormap (red areas). There was no significant effect of the NRGN genotype on GM volume among the healthy controls.(TIF)Click here for additional data file.Figure S3Effect of the risk-T-allele on increased WM regions in the patients with schizophrenia. Effect of the risk T allele on increased WM regions (CC<CT<TT) in the patients with schizophrenia was shown by hot colormap (red areas). There was no significant effect of the NRGN genotype on WM volume among the healthy controls.(TIF)Click here for additional data file.Table S1Demographic information for patients with schizophrenia and healthy controls included in the VBM analysis.(DOC)Click here for additional data file.Table S2Effects of the NRGN genotype on WM volumes in patients with schizophrenia and healthy controls.(DOC)Click here for additional data file.


The aim of this study was to examine the association between the −149C>T polymorphism of DNA methyltransferase 3B (DNMT3B) and colorectal cancer (CRC) susceptibility. A comprehensive search was conducted to identify all case-control studies of the −149C>T polymorphism of DNMT3B and CRC risk. Statistical analysis was performed with the software program Stata (version 12.0) and Review Manager (version 5.0). A total of seven eligible studies, including 2,666 cases and 4,022 controls, associating the DNMT3B polymorphism of −149C>T with the risk of CRC were identified. These studies suggested no significant associations between the −149C>T polymorphism of the DNMT3B gene and the risk of developing CRC in the recessive, dominant and co-dominant models . In the subgroup analysis, no significant associations were found in the European populations . No significant association was found between the −149C>T polymorphism in DNMT3B and CRC susceptibility. Colorectal cancer (CRC) is a worldwide public health problem, resulting in approximately 500,000 mortalities every year . PreviouTo date, no meta-analysis has been conducted to investigate the association between the −149C>T polymorphism of DNMT3B and CRC. Thus, a meta-analysis based on a total of seven independent studies was performed to determine whether there was any evidence of a correlation between the DNMT3B −149C>T polymorphism and CRC susceptibility.We searched the articles using the terms ‘DNMT3b’, ‘DNMT3B’, ‘C46359T’, ‘−149C>T’, ‘rs2424913’, ‘neoplasm’, ‘carcinoma’, ‘tumor’, ‘variation’, ‘colorectal’ and ‘cancer’ in the electronic databases MEDLINE, ISI Web of Knowledge and Embase, without date and language restrictions, and all eligible studies were obtained prior to March 21, 2012. We evaluated the associated literature to retrieve the most eligible studies. The reference lists were hand-searched to find other relevant studies. Of the studies with overlapping data published by the same investigators, only the most recent or complete study was included in this meta-analysis.The following inclusion criteria were used to select studies for this meta-analysis: i) only case-control studies were considered; ii) the study was required to describe CRC diagnoses and the sources of cases and controls and iii) the authors had to provide the size of the sample, odds ratio (OR) and their 95% confidence interval (CI) or the information that infers the results in the studies. Reviews and bibliographies of the relevant studies, and references of all the included studies were also hand-searched. The exclusion criteria were: i) non case-control studies; ii) a control population including malignant tumor patients and iii) duplicated studies.Two investigators reviewed and extracted information from all eligible studies independently, according to the inclusion and exclusion criteria listed above. An agreement was reached by discussion between the two reviewers whenever there was a conflict. The following items were collected from each study: first author’s surname, year of publication, statistical data, ethnicity, total number of cases and controls as well as numbers of cases and controls with CC, CT and TT genotypes. Various ethnicities were classified as European, Asian and mixed populations.The effect measure of choice was OR with corresponding 95% CI. The significance of the summary OR was determined with a Z-test and P<0.05 was considered to indicate a statistically significant result. In the present study, two models of meta-analysis were applied for dichotomous outcomes; the fixed and random effects models. The fixed effects model assumes that studies are sampled from populations with the same effect size, making an adjustment to the study weights according to the in-study variance. The random effects model assumes that studies are obtained from populations with varying effect sizes by calculating the study weights both from the in-study and between-study variances, considering the extent of variation or heterogeneity. Heterogeneity assumption was checked by the Q-test. P≥0.10 for the Q-test indicated a lack of heterogeneity among the studies.First, we examined −149C>T genotypes using additive (CC vs. TT), recessive (CC vs. CT+TT) and dominant (CC+CT vs. TT) genetic models. The comparison of the C allele with T allele was then examined. Funnel plots were produced and an asymmetric plot indicates there is no publication bias. The symmetry of the funnel plot was then evaluated by Egger’s linear regression test. The significance of the intercept was determined by the t-test suggested by Egger . Statistical tests were performed with Review Manager (version 5.0) and Stata (version 12.0) using two-sided P-values.Seven studies on DNMT3B −149C>T geno-types and CRC were identified through the literature search and selection based on the inclusion and exclusion criteria –14. The The meta-analysis of the association of the −149C>T polymorphism of DNMT3B with CRC in an overall population included seven independent studies with a total of 2,666 cases and 4,022 controls. The Q-test of heterogeneity was significant and we conducted analyses using fixed and random effects models.No statistically significant difference was found in CRC risk between the patients with CC genotype and those with TT genotype . Similarly, no significant associations were found in the recessive model (CC vs. CT+TT) comparison  or dominant model (CC+CT vs. TT) comparison . In addition, we did not detect any association between the DNMT3B −149C>T polymorphism and CRC when examining the contrast of C vs. T alleles . In the stratified analysis by ethnicity, significant between-study heterogeneity was detected in all the comparisons in Europeans, but not in Asian and mixed populations. For the European population, there was no significant association between the −149C>T polymorphism and CRC in the additive model comparison  is the most common form of human genetic variation, and may contribute to susceptibility to cancer, however, the underlying molecular mechanism is unknown. Previous studies suggested that certain variants, especially those in the promoter regions of genes, may affect either the expression or activity levels of enzymes –17 and tThe present meta-analysis, including 2,666 cases and 4,022 controls, concerning the −149C>T polymorphism of DNMT3B gene and CRC risk. In the meta-analysis, we did not find that the variant genotypes of the DNMT3B −149C>T polymorphisms were significantly associated with CRC risk. Simultaneously, the same results were observed in a stratified analysis by ethnicity.In this study, we have found that the variant genotype of the DNMT3B −149C>T polymorphism, in the European population, was not associated with a significant increase in CRC risk. This result was consistent with previous studies . AlthougCertain limitations of this meta-analysis should be acknowledged. First, the number of cases and controls in the included studies was not sufficient. Second, our result was based on unadjusted estimates, while a more precise analysis should be conducted and other factors including diet, smoking status, drinking status and environmental factors should be considered. Third, in the subgroup analyses by ethnicity, a relatively limited number of studies available made it impossible to perform ethnic subgroup analysis of Asians and mixed populations. Thus, additional studies are required to evaluate the effect of this functional polymorphism on CRC risk in different ethnicities, particularly in Asians. In addition, our analysis did not consider the possibility of gene-gene or SNP-SNP interactions or the possibility of linkage disequilibrium between polymorphisms.In conclusion, this meta-analysis provided evidence of the association between the −149C>T polymorphisms and CRC risk, supporting the hypothesis that −149C>T polymorphisms were not correlated with overall CRC risk. In the subgroup analysis, the same results were found in European, Asian and mixed populations. To verify our findings, larger and well-designed studies are required to evaluate the association between the DNMT3B −149C>T polymorphism and CRC risk.


However, the evidence is inadequate to draw robust conclusions because most studies were generally small and conducted in heterogeneous populations. To shed light on these inconclusive findings, we conducted a large meta-analysis of studies relating the ACE I/D polymorphism to the risk of ischemic stroke.Many studies have investigated the association between the Relevant studies were identified by searching PubMed and Embase through February 2012 and by reviewing the references of retrieved articles. We included studies that reported odds ratio (OR) with 95% confidence interval (CI) for the association between this polymorphism and ischemic stroke risk.Fifty independent publications, with 10 070 stroke cases and 22 103 controls, were included. The results indicated that the DD homozygote carriers had a 37% higher risk of ischemic stroke when compared with the homozygotes II and heterozygote ID . Subgroup analyses indicated that this higher risk was more pronounced among Asians, hospital-based studies, and small vessel disease (SVD). Potential publication bias may exist, but correction for this bias using a formal statistical method did not materially alter the combined risk estimate.ACE I/D polymorphism is a low-penetrance susceptibility marker of ischemic stroke.The results of our meta-analysis indicate that the D allele of  Stroke is a common neurological disease and a leading cause of death and long-term disability worldwide ACE gene is located on chromosome 17q23, where an insertion/deletion polymorphism  in intron 16 has been identified ACE gene and the risk of ischemic stroke, but the results were inconclusive ACE I/D and risk of ischemic stroke The renin-angiotensin system (RAS) is a hormonal signaling mechanism implicated in the atherosclerosis and regulation of blood pressure ACE I/D and ischemic stroke for various genetic contrasts, in which we explored the between-studies heterogeneity and the existence of potential bias.Therefore, we present herein the results of a large meta-analysis of published data investigating the association between Two online electronic databases (PubMed and Embase) were searched for eligible articles through February 2012. The search was limited to English language full-text papers. Abstract, review or editorials were not included. The medical subject headings and terms used for the search were: stroke, brain infarction, and cerebrovascular disease in combination with ACE, angiotensin-converting enzyme, polymorphism, genotype, gene, or mutation. The references of all identified publications were searched for any additional studies, and the related articles option in PubMed was used to search for further potentially relevant articles.ACE I/D polymorphism and provided cases of ischemic stroke  and control subjects , (2) had neuroimaging (CT or MRI) confirmation of an ischemic stroke diagnosis, (3) evaluation of ACE I/D polymorphism and ischemic stroke risk and (4) sufficient data for examining an odds ratio (OR) with 95% confidence interval (CI). Studies were excluded if: (1) patients were under 18 years of age, or (2) original genotype data was not reported. For duplicate publications, the smaller dataset was discarded.Studies included in our meta-analysis have to meet the following criteria: (1) hypothesis-driven studies specific for ACE I/D polymorphism, source of control groups , and genotyping methods. Different ethnic descents were categorized as European, Asian and African.Two investigators (Z.Z. and G.X.) independently extracted data and reached a consensus on all of the items. For each study, the following characteristics were collected: the first author's last name, year of publication, country of origin, ethnicity, matching conditions, numbers of genotyped cases and controls, the genotype distribution of cases and controls for the 2 test. To measure the strength of genetic association for ACE I/D polymorphism, the ORs, together with the 95% CIs were calculated. The statistical significance of the summary OR was determined with the Z test, and P<0.05 was considered as statistically significant. We first estimated the risks of the ID and DD genotypes on strokes, compared with the wild-type II homozygote, and then evaluated the risks of (ID/DD) vs II and DD vs (ID/II) on strokes, assuming dominant and recessive effects of the variant D allele, respectively. We also estimated the risks of D allele vs A allele. In addition, stratified analyses were performed by ethnicity, source of controls, subtype, gender, and HWE.For each study, we first examined whether the genotype distribution in controls was consistent with Hardy-Weinberg equilibrium (HWE) by χQ-test and I2 statistics Heterogeneity among studies was assessed with the Cumulative and recursive cumulative meta-analysis were performed to provide a framework for updating a genetic effect from all studies and to measure how much the genetic effect changes as evidence accumulates We also performed sensitivity analyses to evaluate the stability of the results. A single study involved in the meta-analysis was deleted each time to reflect the influence of the individual data to the pooled ORs. For assessment of potential publication bias, we used funnel plots and Egger's linear regression test. Moreover, we performed the Duval and Tweedie nonparametric trim and fill procedure to further assess potential effects of publication bias A flow diagram of the literature search is shown in The characteristics of included studies are summarized in ACE I/D polymorphism were associated with a significantly higher risk of ischemic stroke in different genetic models when all the eligible studies were pooled into the meta-analysis. As shown in Ptrend<0.001). In addition, significant main effects were also observed in dominant model, recessive model and allele contrast model .Overall, the variant genotypes of In the stratified analysis by ethnicity, significantly higher risks were found in Asians  but with borderline statistical significance in Europeans  and source of controls , but not the sample size , was found to contribute to substantial heterogeneity.Obvious heterogeneity between studies was observed in overall and subgroup analyses (Pheterogeneity = 0.081). Although the genotype distributions in eight of the included studies did not follow HWE, the corresponding pooled ORs were not materially altered with or without including these studies . Random-effects OR corrected for publication bias using the trim and fill method was 1.19  for all studies combined. Correction for potential publication bias therefore did not materially alter the combined risk estimate.Visual inspection of the Begg's funnel plot showed some asymmetry. Then, the Egger's test was used to provide statistical evidence of funnel plot asymmetry. As expected, the results indicated an obvious evidence of publication bias (t = 3.70, ACE I/D polymorphism and stroke risk. We found that the variant genotypes of this polymorphism were associated with significant increase in overall stroke risk.The present meta-analysis, including 10 070 cases and 22 103 controls from 50 published studies, explored the association between the ACE gene is a good candidate gene for ischemic stroke. Early studies demonstrated a strong correlation between the D allele and levels of circulating, intracellular, and tissue activity of ACE ACE polymorphism may modulate the risk of ischemic stroke. In present meta-analysis, we found that variant genotypes of ACE I/D polymorphism were associated with higher stroke risk, which was consistent with experimental findings.ACE activates angiotensin I and inactivates bradykinin, resulting in decreased tissue perfusion, vascular smooth muscle cell growth Significant associations were found in Asians but with borderline statistical significance in Europeans, suggesting a possible role of ethnic differences in genetic backgrounds and the environment they lived in. The impact of this polymorphism may be masked by the presence of other as-yet unidentified causal genes involved in stroke development in Europeans. Other factors such as selection bias, different matching criteria may also play a role. The above differences may lead to the inconsistent results. In addition, there is only one reported study using African population for this polymorphism. So it is also likely that the observed ethnic differences may be due to chance because studies with small sample size may have low statistical power to detect a slight effect. Thus, additional studies are warranted to further validate ethnic difference in the effect of this polymorphism on stroke risk, especially in Africans.ACE I/D polymorphism may play different roles in the differing subtypes of strokes. Our findings indicate that genetic risk factors for different subtypes are likely different, supporting the view that they are pathologically distinct entities, with SVD having a greater genetic liability compared to LVD.In the subgroup analysis by subtype, significantly higher stroke risk was observed in SVD but with borderline statistical significance in LVD. Stroke is a heterogenous disease and it is possible that No significant association between variant genotypes and stroke risk was observed when the included studies were stratified by gender. The null result may be due to limited number of studies with available data, which had insufficient statistical power to detect a slight effect or may have generated a fluctuated risk estimate.Our findings confirmed results from previous meta-analyses. With the accumulative evidence, we were able to enhance the precision of the risk estimates and perform subgroup analyses to explore sources of heterogeneity, thereby increasing the clinical relevance of our findings. However, some limitations of this meta-analysis should be addressed. First, lacking of the original data of the reviewed studies limited our further evaluation of potential interactions, because the gene-gene interaction and gene-environment interaction may modulate stroke risk. Second, a potential publication bias may exist, as shown by the funnel plot and the Egger's test. Nevertheless, correction for this bias using the trim and fill method did not materially alter the combined risk estimate.ACE I/D polymorphism and stroke risk, supporting the hypothesis that the ACE I/D polymorphism may be a low-penetrance susceptibility marker of stroke. However, additional large studies are warranted to validate our findings. Future studies should use standardized genotyping methods and homogeneous patients and well-matched controls and include multi-ethnic populations. Furthermore, detailed gene-gene interaction and gene-environment interaction should also be considered in future studies, which should lead to better understanding of the association between the ACE I/D polymorphism and stroke risk.In conclusion, this meta-analysis provided evidence of the association between the