To evaluate the role of plasma total homocysteine (tHcy) and homozygosity for the thermolabile variant of the methylenetetrahydrofolate reductase (MTHFR) C677T genotype in the risk of retinal vein occlusion (RVO).Relevant studies were selected through an extensive search of PubMed, EMBASE, and the Web of Science databases. Summary weighted mean differences (WMDs) or odds ratios (ORs) and 95% confidence intervals (CI) were calculated with a random-effects model.P < 0.001), but there was evidence of between-study heterogeneity (P < 0.001). No significant association between MTHFR C677T genotype and RVO was found under all genetic models.Forty-two studies with 6445 participants were included in this updated systematic review and meta-analysis. The mean plasma tHcy level in the RVO patients was significantly higher than in the controls (WMD =2.13 μmol/L; 95% CI: 1.29 to 2.98, There was some evidence that plasma tHcy is associated with an increased risk of RVO. There was no evidence to suggest an association between homozygosity for the MTHFR C677T genotype and RVO. Retinal vein occlusion (RVO) is one of the most common vision-threatening retinal vascular diseases, affecting males and females almost equally and occurring most frequently in elderly subjects , 2. It iHomocysteine (Hcy), a sulfur-containing amino acid formed during the metabolism of methionine, can be remethylated to methionine throughmethyltetrahydrofolate reductase (MTHFR) . SeveralA previous meta-analysis of 25 case–control studies conducted in 2009 showed that elevated tHcy was associated with RVO but not for the MTHFR C677T genotype . HoweverIn the present study, we analyzed the relation among tHcy, the MTHFR C677T genotype, and RVO in an updated meta-analysis of case–control studies. The aim of this updated analysis of 42 studies was to derive a more precise estimation of the relationship among tHcy, the MTHFR C677T genotype, and the risk of RVO.A systematic literature search of PubMed, ISI Web of Science, and EMBASE was performed to identify relevant studies from inception until March 10, 2014. The following terms were used in the searches: “retinal vein occlusion” AND (“homocysteine” OR “methyltetrahydrofolate reductase”). The websites of professional associations and Google Scholar were also searched for additional information. When relevant articles were identified, their reference lists were searched for additional articles. The final search was carried out on March 10, 2014, without restrictions regarding publication year, language, or methodological filter.Studies included in this meta-analysis met the following criteria. The studies (a) contained a laboratory assessment of plasma tHcy concentrations or reported odds ratio (ORs) and their 95% confidence intervals (CIs) of the association between tHcy and RVO, or they assessed the MTHFR C677T polymorphism. Alternatively, (b) articles were retrieved if they were retrospective, prospective, or case–control studies. If multiple publications from the same study population were available, the most recent study would be eligible for inclusion in the meta-analysis. Editorials, letters to the editor, review articles, case reports, meeting abstracts, and animal experimental studies were excluded.Two authors (Z.M.W. and X.Y.P.) independently extracted the following data from the included studies: publication data ; patient condition (fasting status); participant’s age and sex; number of cases and controls; the Hcy levels in the cases and the control subjects; the adjusted ORs of the association between tHcy and RVO; and the genotype counts.Two reviewers independently assessed the quality of each study using the Newcastle-Ottawa Scale (NOS) . The NOSThe weighted mean differences (WMDs) were used to compare the plasma tHcy concentrations between the case and control subjects. The pooled adjusted ORs with their corresponding 95% CIs were used as a common measure of the association between tHcy and the risk of RVO. ORs and 95% CIs were calculated for the MTHFR C677T TT genotype exposure and RVO. The association between MTHFR C677T genotype exposure and RVO was examined using the following genetic models: the homozygote co-dominant (TT vs. CC), heterozygote co-dominant (TC vs. CC), dominant genetic (TT/TC vs. CC), and recessive genetic (TT vs. TC/CC) models.2 statistic. For the Q statistic, P < 0.05 was considered to indicate statistically significant heterogeneity. A meta-regression analysis was used to investigate the influence of the variables on the study heterogeneity across strata. To detect publication biases, we calculated Begg’s and Egger’s measures [P value less than 0.05 was considered statistically significant in the test for the overall effect. The analysis was conducted using the Stata software package .We combined the data using a random effects model to achieve more conservative estimates . Statistmeasures , 26. A PA subgroup analysis was used to investigate which factors  might contribute to heterogeneity. Furthermore, we performed a sensitivity analysis by excluding the low-quality studies and reanalyzing the pooled estimate for the remaining studies.The literature search identified 422 papers. Of these, 196 were excluded because they were duplicate studies. Initially, the title, abstract, and medical subject heading words of the obtained publications were used for a rough judgment on the eligibility of an article. In total, 168 studies, including reviews and case series, were excluded for various reasons, such as being irrelevant to our analysis. The remaining 58 were retrieved for a full-text review. In total, 16 articles were excluded for various reasons. Of these, seven articles were excluded because they provided no data on plasma tHcy concentrations or the prevalence of the MTHFR C677T genotype. Four articles were excluded because they had insufficient data regarding plasma tHcy levels, only reporting on the proportion of hyperhomocysteinemia (hyperhomocysteinemia defined as plasma tHcy >15 μmol/L). Two articles were excluded because they were cross-section studies. Two articles contained duplicated data and one article compared the plasma tHcy concentrations between single-episode CRVO patients and recurrent CRVO patients. Finally, 42 case–control studies were included in this meta-analysis , 27–61. All studies were case–control in design. Table 2 = 93.8%, P < 0.001) across the articles. Therefore, the data were pooled ina random-effects model. The meta-analysis of these data showed that the plasma tHcy level was significantly higher in the RVO patients than in the controls .The analysis of the average plasma tHcy level of the RVO patients and controls in 34 studies revealed significant heterogeneity .We identified nine studies that reported an association between tHcy and RVO. As shown in Figure 2 statistic indicated substantial between-study heterogeneity in all genetic models tested. For MTHFR, the Begg’s test and Egger’s test also showed little evidence of publication biases among the studies . A meta-analysis of data collected before September 2009revealed that the mean tHcy in the cases was 2.8 μmol/L (95% CI: 1.8–3.7) greater than in the controls . Our finThe previous meta-analysis investigated the association between the MTHFR C677T genotype and RVO and found no association between the homozygosity of the TT genotype or RVO. The authors speculated that one possible cause of this lack of association was the modest number of studies included in the meta-analysis. However, with the added statistical power of 1,682 cases, the present meta-analysis also found no significant association between the MTHFR C677T genotype and RVO under all genetic models. Genetic factors are not the only factors capable of increasing the tHcy level; demographic and lifestyle factors, such as age, gender, folate intake, smoking status, vitamin B levels, systemic vascular diseases, and use of antihypertensive medications, can affect the plasma tHcy level .The present meta-analysis identified substantial heterogeneity among the studies. This was not surprising, given the differences in the characteristics of the populations, data collection methods, ethnic populations, sample size, and sources of the cases. Whenever significant heterogeneity was present, a subgroup analysis was conducted, and a random-effects model was used to pool the results. However, our attempts to identify homogeneous subsets largely failed in the subgroup analysis, with heterogeneity remaining in all the subgroups in the studies. The meta-regression analysis also failed to identify the main sources of the heterogeneity. Several factors might account for the heterogeneity. First, environmental exposure and diet might play roles . Second,The previous meta-analysis analyzed data from 25 case–control studies and found that plasma tHcy level was relatively higher in RVO patients compared with controls . The autThe results of the present meta-analysis must be interpreted cautiously in light of the strengths and limitations of the included studies. A major strength of this study is the enlarged sample size, as compared to the previous meta-analysis, and we added 17 newly published case–control studies, which provides enhanced statistical power and offers more precise and reliable effect estimates. Furthermore, we only included the case–control studies and no other studies. In addition, the methodological issues for the meta-analysis, such as publication bias and the stability of results, were well investigated. Our meta-analysis also has several limitations. One potential limitation is the substantial heterogeneity observed among the studies. Second, the case–control study design means that the assessment of tHcy in patients at varying time intervals after the occlusive vascular event is methodologically weak. The vascular occlusive event itself could increase the tHcy concentration. Third, to avoid publication bias, we performed not only an electronic search but also a manual search to identify all potentially relevant papers, including published and non-published sources. Unfortunately, we may have failed to include some papers, especially those published in other languages. Publication bias may have resulted in an overestimate of the relationship between tHcy and RVO. Fourth, in some studies, age was not entirely matched between the case and control groups. There is some evidence that tHcy increases with age, which might have affected the pooled results. Fifth, the controls were not uniformly defined. This was a meta-analysis of case–control studies, and no studies were population-based. Thus, some inevitable selection biases might exist in the results, and they may not be representative of the general population.In conclusion, despite these limitations, the current meta-analysis of observational studies suggests that an elevated level of plasma tHcy increases the risk of RVO. There was no evidence to suggest an association between the MTHFR C677T genotype and RVO. Despite these encouraging findings, the inherent limitations of the included studies should be considered, and conclusions drawn from our pooled results should be interpreted with caution.


Tumor suppressor p53 is a critical player in the fight against cancer as it controls the cell cycle check point, apoptotic pathways and genomic stability. It is known to be the most frequently mutated gene in a wide variety of human cancers. Single-nucleotide polymorphism of p53 at codon72 leading to substitution of proline (Pro) in place of arginine (Arg) has been identified as a risk factor for development of many cancers, including nasopharyngeal carcinoma (NPC). However, the association of this polymorphism with NPC across the published literature has shown conflicting results. We aimed to conduct a case–control study for a possible relation of p53 codon72 Arg>Pro polymorphism with NPC risk in underdeveloped states of India, combine the result with previously available records from different databases and perform a meta-analysis to draw a more definitive conclusion. A total of 70 NPC patients and 70 healthy controls were enrolled from different hospitals of north-eastern India. The p53 codon72 Arg>Pro polymorphism was typed by polymerase chain reaction, which showed an association with NPC risk. In the meta-analysis consisting of 1842 cases and 2330 controls, it was found that individuals carrying the Pro allele and the ProPro genotype were at a significantly higher risk for NPC as compared with those with the Arg allele and the ArgArg genotype, respectively. Individuals with a ProPro genotype and a combined Pro genotype (ProPro+ArgPro) also showed a significantly higher risk for NPC over a wild homozygote ArgArg genotype. Additionally, the strength of each study was tested by power analysis and genotype distribution by Hardy–Weinberg equilibrium. The outcome of the study indicated that both allele frequency and genotype distribution of p53 codon72 Arg>Pro polymorphism were significantly associated with NPC risk. Stratified analyses based on ethnicity and source of samples supported the above result. The disease is treatable at an early stage but the majority of NPC patients are diagnosed at a late stage because of the exhibition of nonspecific symptoms related to other head and neck illnesses.9 However, many individuals exposed to these parameters do not develop NPC, which indicates the involvement of genetic factors. To establish a link between genetic factors and NPC development, study of single-nucleotide polymorphism (SNP) in tumor suppressor genes has been the focus of many researchers.Epidemiological studies suggest the association of food habits , lifestyle  and viral infection (Epstein–Barr virus and human papilloma virus) in the etiology of NPC.12 Deregulated function of p53 may result in loss of this regulation, resulting in uncontrolled cell proliferation and cancer development.15 Polymorphisms in p53 or target genes impair the function of the p53 signaling pathway.16 The most studied polymorphism in p53 is located in exon 4 at codon72. It carries either the CGC sequence that encodes arginine or the CCC sequence that encodes proline due to G/C transversion.18 As a result, two allelic forms (Arg and Pro) and three genotypes  have evolved. These allelic variants and genotypes oscillate in their binding capacity to the transcriptional factors, induction of apoptosis and repression of transformation of human cells.20 Arg variants induce apoptosis more efficiently than do the Pro variants, which may be due to their ability to localize into mitochondria and regulate the release of cytochrome C into cytosol.18 The released cytochrome C in turn activates caspase-3, one of the key executioners of apoptosis.22 This difference between Arg and Pro variants may provide the plausible cause for Pro allele's involvement in increased susceptibility to NPC. Earlier, several studies including our present study among the populations of north-eastern India have investigated the relation between p53 codon72 Arg>Pro polymorphism and NPC risk.32 The purpose of a case–control study of north-eastern Indian populations was also to find out the incidence of different stages of NPC among them and to examine the clinical symptoms manifested by them. However, these findings were inconsistent and inconclusive. In view of the fact that a single study may have been underpowered in clarifying the association, we performed a meta-analysis to combine the findings of all earlier studies from public records and data from the present study according to PRISMA 33 guidelines to explore the overall association and derive a near-specific conclusion.p53 is a well-established tumor suppressor gene located on chromosome 17p13.1. It plays a critical role in response to genotoxic stress and tries to maintain genomic stability and control proper execution of the cell cycle and apoptotic pathways.34 The incidence rate of this cancer is highest in south-east Asia and about 92% of new cases are being found in economically developing countries.34 In India, this rate is comparable to that of the United Kingdom with the younger age peak in the second decade.36 Several susceptible genes have been implicated for NPC risk, such as tumor suppressor p53, TGFβ1, IL-12 p40 and DNA repair genes.39 In contrast, FokI and Bsm I polymorphisms of vitamin D receptor gene, SNP of deleted in liver cancer-1 (−29A/T) showed no association with NPC.41 However, polymorphisms in PIN-1, TNF-α and glutathione S-transferase genes are indirectly associated with NPC as they influence the p53 codon72 polymorphism.44 These studies suggest that genetic predisposition may play a role in NPC development. Hence, we conducted a study in the north-eastern Indian population among healthy controls and NPC patients to find out the prevalence of p53 codon72 Arg>Pro polymorphism   .et al., in 1996, and Yung WC et al., in 1997 demonstrated no association between the mutant p53 codon72 and the risk for NPC.23 Subsequently, Tsai et al.,24 in 2002, reported that the p53 ProPro homozygote was a risk factor for NPC development. In the Thai population, Tiwawech et al.,25 in 2003, reported that the p53 gene polymorphism may be associated with NPC susceptibility, particularly the Pro/Pro genotype carriers in subjects older than 40 years. In Portugal, Sousa et al.26  in 2006 reported similar findings linking the susceptibility of the P53 codon72 polymorphism to NPC. Further, Hadhri-Guiga et al.,27 in 2007, found that individuals carrying the ProPro homozygote carried an elevated risk for NPC in Tunisia. Similarly, Xiao M et al.,29 in 2010, found that the p53 codon72 polymorphism carried an increased NPC risk independently or in combination with the murine double minute-2 (MDM2) polymorphism in a Chinese population sample, suggesting a gene–gene interaction in NPC pathogenesis. Furthermore, Li et al.,28 in 2013, reported that p53 codon72 and miR-34b/c rs4938723 polymorphisms may singly or collaboratively contribute to the risk for NPC. Two more studies reported this polymorphism as an independent prognostic marker for NPC, and hence one could speculate that this polymorphism means more risk for incidence and more risk for an aggressive disease.46 Moreover, Zhang et al., in 2014, observed a weak effect of p53 polymorphisms on NPC risk. However, they found a significant risk with combination genotypes .30 Overall, variability in study results may be attributed to variation in study design, environmental factors, genetic backgrounds, racial heterogeneity, sample size, source of controls and enrollment criteria for NPC cases. A previous meta-analysis showed that the ProPro homozygote of p53 codon72 possesses an increased NPC risk.47 In another meta-analysis, Jiqiao Yang et al.48 analyzed publicly available data under five comparison models  and showed the association of p53 codon72 Arg>Pro, MMP-1 (1G>2G), MMP-2 (−1306C>T), CYP2E1 (RsaI) and XRCC1 codon399 Arg>Gln polymorphism with increased risks for NPC.The p53 codon72 SNP has been studied by many groups across the world. In the Chinese population Birgander 32 Thus, a total of 10 case–control studies counting 1842 NPC patients and 2330 controls comprising populations from India, China, Tunisia, Portugal and Thailand were included in the final meta-analysis . In the north-eastern Indian population, the minor allele frequency of the p53 codon72 Arg>Pro was 0.37 for controls and 0.56 for NPC. The power of this case–control study was too weak (23%) to detect any mild effect of the polymorphisms on disease susceptibility.In our meta-analysis, all eligible reports that fulfilled the inclusion criteria were identified from publication search and the data from the north-eastern Indian population were also included for evaluation.analysis . The chaP>0.05, except the study in the north-eastern Indian population   and I2 statistics (Q-statistic was significant (PH<0.05), which indicates heterogeneity across studies. The fixed-effect model was employed when PH⩾0.05. In the overall population, the fixed-effect model was employed for meta-analysis of the p53 codon72 Arg>Pro polymorphism in four comparison models . However, the ProPro vs ArgArg+ArgPro comparison model showed heterogeneity among studies in the overall population and the random-effect model was used.Significant associations between p53 codon72 Arg>Pro polymorphism and NPC risk were observed in the combined analysis of overall studies  . StratifR=0.002)  and foreR=0.002) . Stratifhan 0.05 . Howeveratistics . The ranIn the stratified analysis, the fixed-effect model was employed in all comparison models of Asian studies except the Pro vs Arg comparison, in which the random-effect model was used. In Caucasian studies the fixed-effect model was employed in all comparison models. In population-based and Chinese studies the fixed-effect model was employed in all comparison models except in the ProPro vs ArgArg+ArgPro comparison model, which reflects the combined results of the overall study. In hospital-based studies the fixed-effect model was employed in three comparison models  and the random-effect model in two comparison models (ArgPro vs ArgArg and ProPro+ArgPro vs ArgArg). The overall pooled results indicate that the p53 codon72 polymorphism is a significant risk factor in the pathogenesis of NPC. Stratified analyses in Asian, Caucasian, hospital-based, population-based and Chinese case–control studies corroborate this association. This meta-analysis supports the findings in north-eastern Indian populations. To our knowledge, the current study is the first to analyze the p53 codon72 polymorphism and association with NPC in the Indian population.In conclusion, our case–control study in North Indian populations and meta-analysis results as evidenced from five genetic models suggest that the p53 codon72 Arg>Pro polymorphism could be employed as a risk factor for NPC. However, some limitations exist in the current meta-analysis. Association of p53 codon72 polymorphism with susceptibility to the histological and clinical grade of NPC patients has not been investigated because of lack of available data on the subject.49 Notably, Epstein–Barr virus infection modulates the effect of the p53 family22 and is a well-nown risk factor for NPC. Nevertheless, whether the p53 Arg or the Pro form is also susceptible to degradation by viruses or by other infectious agents needs to be investigated. Further, as there are a large number of SNPs for p53, the SNP studied in the present analysis was limited only to the functionally important one. In future, screening of all p53 and related polymorphisms in larger samples based on ethnicity in view of confounding factors such as age, sex, cigarette smoke, tobacco use, alcohol intake, dietary habit, stages of NPC and socioeconomic status is required to validate the findings.The p53 Arg form is more susceptible to degradation than the Pro form by human papilloma virus E6 protein.


It exerts its activity through the intracellular vitamin D receptor (VDR), which regulates the transcription of genes. This study aimed to investigate the genetic association of VDR polymorphisms with renal cell carcinoma (RCC) risk in the Chinese population. The genotypes of five VDR polymorphisms  were studied using polymerase chain reaction in 302 RCC patients and 302 healthy controls. ApaI variant AA and AC genotypes were found to be associated with a significantly increased risk of RCC compared with the CC genotype . The AA genotype was also associated with a higher Fuhrman grade . No significant difference was found between the other four VDR polymorphisms and RCC risk. Our study suggests that VDR ApaI genotypes may be involved in the increased risk and progression of RCC in the Chinese Han population.Molecular epidemiologic studies previously reported that 1,25-dihydroxy vitamin D Kidney cancer is the 13th most common malignancy worldwide, with around 270,000 cases diagnosed annually, and 116,000 people dying each year from the disease22 D3), to the vitamin D receptor (VDR), causing a conformational change and leading to dimerization with the retinoid X receptor. The dimeric complex then interacts with vitamin D response elements in target genes involved in cell division, cell adhesion, and function, resulting in changes in gene activityVDR genetic variation may elucidate the role of vitamin D in RCC etiology.Epidemiological and laboratory investigations have shown that vitamin D deficiency is associated with several diseases, including autoimmune diseases, tuberculosis and cancer. Vitamin D maintains calcium homeostasis and regulates the growth and differentiation of various malignant tumors. Its activity is mediated through the binding of its active form, 1,25-dihydroxyvitamin D3 VDR is located on the long arm of chromosome 12q12-q14, and several single nucleotide polymorphisms (SNPs) within the gene have been identified that may influence cancer risk. Each polymorphism is named according to the restriction site that was initially used to identify it. The FokI (rs2228570) polymorphism is located at the first potential start siteVDR mRNAVDR, FokI (C/T), BsmI (A/G), ApaI (A/C), TaqI (T/C), and Cdx2 (A/G), were previously extensively studied for their association with cancer risk8VDR genotype with RCC patients, and the results has not been consistent1112I rs222850 polymorVDR variants and RCC risk in the Chinese Han population.Therefore, to determine whether variation in vitamin D receptor modify RCC risk, we conducted a case–control study to evaluate the association between P = 0.006) and hypertensive patients (P = 0.029) were observed in the RCC group compared with the controls . Multivariate logistic regression analyses showed that patients with AA and AC genotypes of the ApaI polymorphism had a significantly increased RCC risk compared with those with the CC genotype . The ApaI polymorphism A allele was also associated with an increased risk of RCC between cases and controls (P = 0.001). However, no significant association was found between variant genotypes of the other four VDR polymorphisms and risk of RCC (P > 0.05).Genotype and allele distributions of P = 0.766). There were no significant associations between the other four VDR polymorphisms and AJCC stages or Fuhrman grades in all patients.VDR ApaI variant and RCC risk in the Chinese Han population. Patients with AA and CA genotypes of the ApaI polymorphism were shown to have a 2.66- and 1.47-fold increased RCC risk, respectively, compared with those with the CC genotype. We also found that the ApaI polymorphism AA genotype was associated with a higher Fuhrman grade of RCC. However, none of the other four polymorphisms  were associated with the incidence of RCC. These results provide evidence for a potential role of inherited VDR variants in the development of RCC.In this study, we observed a significant association between the VDR in relation to RCC. For example, a recent case–control study of 135 RCC patients and 150 controls in a Japanese population found that participants with the ApaI site AA genotype had a significant increase in RCC risk and a poor prognosis16A few previous studies have comprehensively analyzed the genetic variation in VDR SNP that has been most analyzed because of its functional significance. The FokI C allele encodes a VDR protein lacking three amino acids compared with that encoded by the T allele, which results in enhanced VDR transcription activity. In an earlier study conducted in Central and Eastern Europe, the prevalence of three common VDR SNPs  did not differ according to tumor stage or gradeet al., which analyzed associations of VDR SNP genotypes with RCC progression in terms of AJCC stage and nuclear grade, reported that FokI and BsmI were significantly associated with increased RCC risk among the North Indian population1819VDR promoterFokI is the VDR SNPs and RCC risk. We didn’t perform further subgroup stratification analysis by smoking or obesity because of the insufficient of our data. Moreover, our study population was only of Han Chinese; thus, more comprehensive studies involving larger sample sizes of ethnically diverse populations are warranted to validate these findings.Like other complex diseases, RCC appears to be caused by both genetic and environmental factors, such as cigarette smoking, obesity, and hypertension22VDR is associated with RCC risk in the Chinese Han population. It also suggests that the ApaI polymorphism is a potential determinant of prognosis in terms of Fuhrman grade in RCC patients. Additional studies are needed to fully elucidate the role of VDR genetic variation in RCC risk.In conclusion, this study indicates that the ApaI polymorphism of A total of 302 RCC Chinese Han patients and 302 healthy controls were recruited between November 2009 and April 2012 at the First Hospital of China Medical University . All patients were recruited after a radiologic and histologic diagnosis of RCC. Detailed information about age, sex and clinical characteristics were obtained for all participants see . The hisGenomic DNA was extracted from 200 μL of whole blood samples using the QIAamp DNA Micro Kit  according to the manufacturer’s instructions. Extracted DNA was dissolved to a concentration of 30 ng/μL and was stored at −80 °C. High-resolution melting methods using the LightCycler® 480 system  were used for SNP genotyping according to a previously reported protocol2) test was used to evaluate the Hardy–Weinberg equilibrium (HWE) of the gene frequencies of the healthy individuals. Differences in frequency distributions of epidemiological factors between RCC cases and controls were tested using the Student’s t-test for continuous variables and the χ2-test for categorical variables. To avoid spurious associations due to a small number of homozygous individuals, we used the dominant model for TaqI and BsmI to evaluate associations between the genotypes and RCC risk. The associations between VDR polymorphisms and RCC risk were estimated by calculating odds ratios (ORs) and 95% confidence intervals (CIs). from unconditional logistic regression analysis, adjusting for age and sex. The ORs and 95%CI were calculated by multivariate logistic regression analyses, adjusted for the effect of covariates like sex, age, smoking and hypertension status. All statistical tests were two-tailed with P-value < 0.05 considered as statistically significant. All statistical analyses were performed using the SPSS statistical package, version 19.0. .A goodness-of-fit chi-squared .


Published data on the association between AURKA polymorphisms and breast cancer (BC) risk are inconclusive. This meta-analysis was performed to derive a more precise estimation on the relationship between AURKA polymorphisms (rs2273535 and rs1047972) and BC risk.PubMed, Web of Knowledge and Embase were searched for relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the strength of associations. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were performed for allele contrast genetic model, homozygous genetic model, heterozygote genetic model, dominant model, and recessive model, respectively.P = 0.02; AA vs. TT: OR = 1.36, 95% CI = 1.06-1.73, P < 0.00001; AA vs. TT + TA: OR = 1.15, 95% CI = 1.01-1.31, P = 0.04). In the subgroup analysis by ethnicity, the effects remained in Asians . However, no genetic models reached statistical association in Cauasians. Rs1047972 polymorphism was associated with BC risk in the overall population based on homozygote comparison . When stratified by ethnicity, rs1047972 polymorphism had a decreased association with BC risk in Caucasians based on allele contrast genetic model, homozygote comparison, the dominant model and the recessive model. However, there was no association in any genetic model in Asians.A total of 13 studies  were involved in this meta-analysis. Meta-analysis showed that there was significant association between rs2273535 and BC risk in three genetic models in the overall population (A vs. T: OR = 1.08, 95% CI = 1.01–1.15, This meta-analysis suggests that AURKA rs2273535 polymorphism has an increased risk with BC, especially in Asians. However, rs1047972 polymorphism has a decreased BC risk in Caucasians. Further large scale multicenter epidemiological studies are warranted to confirm this finding. Breast cancer (BC) is the most common cancer in women and the incidence has increased in recent years worldwide . BC is aAURKA, also known as STK15/Aurora-A, belongs to the Aurora family of cell cycle-regulating serine/threonine kinase . AURKA pTwo nonsynonymous polymorphisms F31I (rs2273535) and V57I (rs1047972) have been identified in the AURKA gene. Both polymorphisms are located within two conserved motifs in the N-terminal region of the AURKA gene . SeveralTherefore, we carried out this meta-analysis on all eligible case–control studies to derive a more precise estimation of the associations between AURKA polymorphisms (rs2273535 and rs1047972) with BC risk.We searched the articles in PubMed, Web of Knowledge and Embase to collect articles with case–control studies related to the association of AURKA polymorphisms and BC risk. The keywords were as follows: breast cancer/breast carcinoma, AURKA/Aurora-A/STK15, polymorphism/genotype/SNP. All qualified studies were searched until May 30, 2014. The eligible articles must be published in English. Furthermore, reference lists of main reports and review articles were also reviewed by a manual search to identify additional relevant publications.The following criteria were used to select studies for further meta-analysis: (1) case–control studies; (2) the studies evaluated the associations between AURKA polymorphisms and breast cancer risk; (3) all cases were diagnosed by pathological examination; (4) the studies contained sufficient genotype data for estimating an odds ratio (OR) with 95% confidence interval (CI); (5) genotype distributions of controls passed Hardy-Weinberg equilibrium (HWE) test.Accordingly, the following exclusion criteria were also used: (1) the design of the experiments were not case–control studies; (2) the source of cases and controls, and other essential information were not provided; (3) the genotype distribution of the control population was departure from HWE; (4) reviews, meta-analysis and duplicated publications.Information was carefully extracted from all eligible studies independently by two authors according to the inclusion criteria listed above. In case of disagreements, another author was consulted to resolve the dispute, and a final decision was made by the majority of the votes. For each included study, the following information was collected: first author, year of publication, country of origin, ethnicity, source of control, numble of cases and controls, genotype methods, allele and genotype frequencies and evidence of HWE in controls. Different ethnicity descents were categorized as Caucasian, Asian, and “mixed”. All the case and control groups were well controlled. The non-cancer controls had no history of gynecologic disease, and there was no present evidence of any malignant disease.2 statistics. If the P value of heterogeneity test was more than 0.1 (P ≥ 0.1), the pooled OR estimate of the study was calculated by the fixed-effects model. Otherwise, the random-effects model was used [2 < 25%: no heterogeneity; 25% < I2 < 50%: moderate heterogeneity; 50% < I2 < 75%: high heterogeneity; I2 > 75%:extreme high heterogeneity). Publication bias were evaluated by the funnel plot and further assessed by the method of Egger’s linear regression test. All statistical analyses were carried out with the review manager version 5.1 .The associations between AURKA polymorphisms and BC risk were measured by odds ratio (OR) with 95% confidence interval (CI). The significance of the pooled OR was determined by the Z test. Statistical heterogeneity among studies was assessed with the Q and Iwas used . The valAs shown in Figure As shown in Table P =0.02; AA vs. TT: OR = 1.36, 95% CI = 1.06-1.73, P < 0.00001; AA vs. TT + TA: OR = 1.15, 95% CI = 1.01-1.31, P = 0.04), while there was no significant association in heterozygote comparison and the dominant model . In the subgroup analysis by ethnicity, the effects remained in Asians . However, no genetic models reached statistical association in Cauasians . There was no association in these four genetic models ; recessive model . When stratified by ethnicity, rs1047972 polymorphism had a decreased association with BC risk in Caucasians based on allele contrast genetic model: OR = 0.92, 95%CI = 0.86-0.98, P = 0.01; homozygote comparison: OR = 0.74, 95% CI = 0.59-0.93, P = 0.009; dominant model: OR =0.92, 95% CI = 0.86-1.00, P = 0.04); recessive model . However, there was no association in any genetic model in Asians.5 studies with 7,090 cases and 11,119 controls were used to assess the relationship between rs1047972 polymorphism and BC risk. As shown in Table P > 0.05).Begg's funnel plot and Egger's test were performed to assess the publication bias. As shown in Figure AURKA is associated with centrosomes, being localized at the centrosome just prior to the onset of mitosis and for the duration of mitosis. Overexpression of AURKA leads to centrosome amplification and cellular transformation . This thEpidemiological studies have been performed to assess the association of AURKA polymorphisms (rs2273535 and rs1047972) with BC risk. However, the results are conflicting. Thus, we conducted a comprehensive meta-analysis involving published data, to assess the strength of association between the two polymorphisms and BC risk. In this present meta-analysis, 13 studies with 16,286 BC patients and 20,689 case-free controls concerning the rs2273535 polymorphism, 5 studies with 7,090 cases and 11,119 controls concerning the rs1047972 polymorphism, were included, respectively. And we explored the association between the two potentially functional polymorphisms of AURKA and BC risk.P =0.02; homozygote comparison: OR = 1.36, 95% CI = 1.06-1.73, P < 0.00001; recessive model: OR = 1.15, 95% CI = 1.01-1.31, P = 0.04). However, rs1047972 polymorphism had a decreased association with BC risk based on homozygote comparison .In the overall population, we found that rs2273535 polymorphism had an increased association with BC risk in three genetic models (allele contrast genetic model: OR = 1.08, 95% CI = 1.01–1.15, In the stratified analysis based on ethnicity, rs2273535 polymorphism had increased BC risk in Asians based on allele contrast genetic model, homozygote comparison, and the recessive model. However, no genetic models reached statistical association in Cauasians. For rs1047972 polymorphism, there was no significant association in Asians. Rs1047972 had a decreased BC risk in Caucasians based on allele contrast genetic model, homozygote comparison, the dominant model, and the recessive model.In a previous meta-analysis by Qin et al. , they faThere are some limitations in this meta-analysis. Firstly, this meta-analysis was based on pooled data. We could not assess the risk of cancer according to stratification of age, smoking, alcohol consumption, environment factors, and other risk factors. Secondly, no individual data such as pathological type, histologic grade, and other clinicopathological index was available. Thus, we could not assess the clinicopathological significance of the polymorphisms in BC. Thirdly, there were only published studies including in the meta-analysis. It is possible that some related unpublished studies that might meet the inclusion criteria were missed. Finally, the included studies were mainly based on Caucasian background. There were only four studies based on Asian background and none based on African background. Further large scale multicenter studies based on Asian or African are warranted to further validate on AURKA polymorphisms and BC risk.In summary, this meta-analysis suggests that AURKA rs2273535 polymorphism has an increased risk with BC, especially in Asians. However, rs1047972 polymorphism has a decreased BC risk in Caucasians. Our results indicate that AURKA rs2273535 is a candidate gene polymorphism, and rs1047972 polymorphism is a protective factor for BC cancer risk. We conclude that the two polymorphisms may be potential biomarkers in diagnosis and prediction of BC risk. Further large scale epidemiological studies are needed to confirm these findings.


ZCWPW1 showing strong association with late-onset Alzheimer's disease (LOAD) in Caucasian. However, the effect of rs1476679 on other populations remains unclear. In order to explore whether rs1476679 is also associated with the LOAD risk in other ethnic groups, we recruited 2350 unrelated Northern Han Chinese subjects, which include 992 LOAD patients and 1358 healthy controls. Analysis of data from these subjects suggests that the rs1476679 polymorphism is significantly associated with the LOAD . The logistic regression reveals the C allele at rs1476679 is a protective factor for LOAD in the dominant model  adjusting for gender, age and APOE ε4 status. Furthermore, rs1476679 can decrease the AD risk  in APOE ε4 non-carriers after stratification. Furthermore, meta-analysis of 82525 individuals confirmed that rs1476679 within ZCWPW1 decreased the risk of LOAD . To summarize, the rs1476679 polymorphism in ZCWPW1 is associated with LOAD in Northern Han Chinese population.Recently, a large genome-wide association study (GWAS) has identified a novel variant (rs1476679) within  However, only the ε4 allele of the apolipoprotein E (APOE) gene increases the risk of late-onset AD (LOAD). Unfortunately, APOE only contributes to approximately 20% of LOAD risk, suggesting that numerous additional AD risk loci have not been identified so far. Previous GWAS identified some other genomic regions associated with LOAD, including CLU, PICALM, CR1, BIN1, MS4A, CD2AP, CD33, EPHA1, ABCA7, TREM2, etc. [Alzheimer's disease (AD) is a genetically complex multifactorial neurodegenerative disorder and can be regarded as the most common type of dementia, defined by extensive neuronal and synapses loss, the formation of extracellular he brain . Even thhe brain . PreviouM2, etc. .ZCWPW1 (rs1476679) can be seen as a member of them and have functional relevance [ZCWPW1 . ZCWPW1 is a histone modification reader and is involved in epigenetic regulation [ZCWPW1 serves as an eQTL (expression quantitative trait loci) for GATS, PILRB and TRIM4 and show indications for affecting binding of RFX3 and CTCF [NYAP1 in the ZCWPW1 region may activate the PI3K signaling pathway in neurons and thus inhibit LOAD incidence [ZNF3 lies at the same locus on chromosome7 as ZCWPW1, interacts with BAG3 which is response for ubiquitin/proteasomal functions in protein degradation and binding of BACH1 whose target genes have roles in the oxidative stress response and control of the cell cycle [ZCWPW1 in LOAD.Recently, a large-scale GWAS study of AD, which included 74,046 individuals, adopted a two stage design and carried out a meta-analysis. 11 new discovered loci were found in this meta-analysis, gulation . ZCWPW1 and CTCF . BesidesZCWPW1 rs76679 canll cycle . StudiesZCWPW1 in various ethnic groups might be different, replication is necessary to confirm the potential effects of ZCWPW1 on other groups. In this study, we firstly conducted the genetic association study on rs1476679 within ZCWPW1 in Han Chinese.However, note that this GWAS study was conduct only in Caucasian populations , and theP = 0.067) and gender (P = 0.189). The demographic and clinical characteristics of AD and control subjects are summarized in Table P < 0.001). The possession of at least one APOE ε4 allele was confirmed to increase the risk of developing LOAD . Then we examined the underlying association of the rs1476679 polymorphism with the LOAD susceptibility.We analyzed data from 2350 ethnic Northern Han Chinese subjects, which include 992 subjects (42%) with probable LOAD and 1358 healthy control subjects (58%) matched for age . Based on the minor allele (C) frequency in controls, our sample size had more than 95% power to detect the OR of 0.78 for LOAD between carriers and no-carriers, at a significance level  of 0.05. The allele and genotype distributions of rs1476679 AD patients and control subjects are shown in Table P = 0.044). Similarly, the genotypes of the LOAD patients were significantly different from those of the controls (P = 0.017). As showed in Table P = 0.003, Pc = 0.009) in total sample .Genotype distributions of the rs1476679 in APOE ε4 genotype on the risk of developing LOAD, we analyzed them in logistic regression models. No interaction between rs1476679 and APOE ε4 status was observed after Bonferroni adjustment. To further investigate whether the presence of the APOE ε4 allele significantly modified the association of rs1476679 with LOAD, these data were stratified based on the presence/absence of the APOE ε4. The genotype and allele distributions in rs1476679 between LOAD patients and controls are significantly different  from subjects without APOE ε4 allele. In the subjects with APOE ε4 allele, the genotypic distributions (P = 0.049) have differences between LOAD and controls. However, no significant differences were observed in the allelic distributions (P = 0.385) between these two groups  . Analysis using the recessive models indicate that rs476679 has no effect on the development of LOAD neither in APOE ε4 allele noncarriers (P = 0.764) nor in APOE ε4 allele carriers after a Bonferroni adjustment (Pc = 0.138).Furthermore, to test the influence of the interaction between rs1476679 and ps Table . Multiva2 = 20.4%), and the statistical significance of the factors with a low heterogeneity was essentially unchanged from our current study and previous report.We conducted a meta-analysis on the association of rs1476679 and LOAD in a sample of 82525 individuals, and found rs1476679 showed significant association with LOAD   that rs1476679 decreased the risk of AD in Caucasian . A folloZCWPW1 result to LOAD, rs1476679 may be in LD with functional SNPs in ZCWPW1 gene. ZCWPW1 contains the zinc finger CW (zf-CW) domain and the PWWP domain, shows functions in giving rise to chromatin remodeling and methylation states, as well as epigenetic regulations, respectively, indicating ZCWPW1 as a histone modification reader [ZCWPW1 serves as an eQTL (expression quantitative trait loci) for GATS, PILRB and TRIM4 and affects binding of CTCF and RFX3, a variant in ZCWPW1 (rs1476679) associated with LOAD risk was considered to have functional relevance [ZCWPW1 decreases risk of LOAD through suppressing insulin resistance [Regarding to the mechanisms by which the SNP in n reader , 21. As sistance .ZCWPW1 defined by SNPs associated with LOAD is part of a larger LD block, encompassing many candidate genes [ZCWPW1 region is NYAP1, which disruption affects brain size, inhibits neurite elongation and, neuronal morphogenesis [NYAP1 has role in the regulation of the PI3K signaling pathway in neurons, means it associates with AD risk mainly in this pathway [ZNF3 lies at the same locus on chromosome 7 as ZCWPW1, thereby it can be regarded as a candidate gene that contains the functional signal in this region [ZNF3 may interact with BAG3  and binding of BACH1 (acting on the oxidative stress response and regulating the cell cycle), which are involved in tau pathology of AD. NYAP1 and ZNF3 might participate in mechanisms of AD through the above pathways, although no studies reported the association between NYAP1 or ZNF3 gene and AD risk [The region of te genes . Anotherogenesis . NYAP1 h pathway . In addis region . ZNF3 ma AD risk .ZCWPW1 (rs1476679) was significant associated with LOAD in a North Han Chinese population. In consistent with the role of ZCWPW1 (rs1476679) in Caucasians, ZCWPW1 (rs1476679) also acted as a protective factor to the development of AD in Han Chinese. Further functional examinations into this locus and the region surrounding ZCWPW1 are required to better elucidate the role of them and their interaction with ZCWPW1 in AD pathogenesis. Besides, studies in more large cohorts and in other ethnic groups are needed to clarify the role of the locus at ZCWPW1 in LOAD since genetic variations vary among the populations of different ethnic and geographical origin.In conclusion, our study provided the first evidence that the carriage of C allele on the Our study investigated 2350 subjects comprising 992 sporadic LOAD patients (mean age at onset: 75.17 ± 6.08 years) and 1358 healthy controls subjects (mean age at examination: 75.49 ± 6.48 years) matched for age and gender. All the LOAD patients and control subjects are unrelated northern Han Chinese residents originally from Shandong Province, which is located in the North of China. The AD patients were recruited from the Department of Neurology at Qingdao Municipal Hospital, and several other 3A-level hospitals in Shandong Province. All patients were subjected to neuropsychological examination, structural neuroimaging consisting of brain computed tomography and/or magnetic resonance imaging. A consensus clinical diagnosis of probable AD was carried out by at least two neurologists according to the criteria of the National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association (NINCDS/ADRDA) . All theZCWPW1 (rs1476679) and APOE (rs429358 and rs7412) polymorphisms were accomplished by the improved multiplex ligase detection reaction (iMLDR) method, with technical support from the Shanghai Genesky Biotechnology Company (genotyping details are available from the corresponding author) [Genomic DNA was extracted from the peripheral blood leukocytes of AD patients and healthy individuals using the Wizard genomic DNA purification kit . Genotyping of t test or the χ2 test. The distributions of genotypes and alleles between the two groups were compared using the χ2 test. Differences between the two groups after stratification for APOE ε4 status were also examined by the χ2 test. For further analysis of the frequencies of the AD patients and control subjects, we defined various genetic models as 1 (CC + CT) versus 0 (TT) for dominant, 1 (CC) versus 0 (CT + TT) for recessive, and 2 (CC) versus 1 (CT) versus 0 (TT) for additive. We then tested them using logistic regression adjusted for age, gender, and APOE ε4 status . The significance of an SNP ×APOE ε4 interaction was also tested for this SNP by logistic regression. The P value, odds ratios (ORs) and 95% confidence intervals (CIs) were computed. The criterion for significant difference is P < 0.05. A Bonferroni-corrected P (Pc) value was computed to control false discovery rate. Estimation of the statistical power was performed with STPLAN 4.3 software.Statistical analysis was calculated using SPSS16.0 software. Genotype and allele frequencies were computed by counting. Hardy–Weinberg equilibrium was tested using the chi-square test. Disparity of the characteristics between AD patients and control subjects were tested by the Student-ZCWPW1 (rs1476679) and LOAD [2 estimates with evaluate the possible effect of study heterogeneity on the results. We used Stata V.12.0 to perform all the meta-analyses.Furthermore, we combined our data with the results from meta-analysis of 74,046 individuals  and otheand LOAD –18 by fi


Evidence exists for the presence of a specific facial phenotype in nonaffected first-degree relatives of persons with CL/P. An increased risk for olfactory dysfunction has also been reported in CL/P-relatives. These phenotypic features can probably be explained via the presence of CL/P-related susceptibility genes. We aimed at confirming the occurrence of these endophenotypic traits in first-degree CL/P-relatives, and we investigated the link between the facial phenotype and the smell capacity in this group. We studied the facial morphology of 88 nonaffected first-degree relatives of patients with CL/P and 33 control subjects without family history of facial clefting by 3D surface imaging and a spatially dense analysis of the images. Smell testing was performed in 30 relatives and compared with 23 control subjects. Nonaffected relatives showed midface retrusion, hypertelorism, and olfactory dysfunction, compared to controls. In addition, we show for the first time that olfactory dysfunction in relatives is correlated to a smaller upper nasal region. This might be explained by a smaller central olfactory system. The different facial morphology in the relatives with olfactory impairment as compared to the total group may be an illustration of the contribution of different genetic backgrounds to the occurrence of CL/P via different biological pathways. Orofacial clefts are among the most common birth defects with a prevalence of approximately 1 in 700 live births . NonsyndIn an attempt to unravel the genetic architecture of nonsyndromic cleft lip and/or palate (NSCL/P), it can be useful to focus on the phenotype of nonaffected first-degree relatives of these patients since they have a high chance to carry genetic susceptibility loci for NSCL/P. This can result in identifiable characteristics, so-called endophenotypes . By defiThe face harbours a treasure of information. It is not only an indication of physical health, sex, environmental exposures, kinship, and ancestry, but also a valuable source of genetic information , 11. TheWe aimed at studying the facial endophenotypes of first-degree relatives of persons with NSCL/P as compared with persons without CL/P family history, using more precise analysis tools, that is, spatially dense facial analysis. In addition, olfactory function in nonaffected first-degree relatives of patients with NSCL/P was investigated using a validated smell test and the results were again compared to a control group without CL/P family history. It is however not yet described whether the cause of this endophenotype is completely structural or if other factors are involved. Therefore, in addition, the relationship between the facial characteristics  and the smell capacity in nonaffected first-degree relatives of patients with NSCL/P was studied as well. To the best of our knowledge, this study is the first in its kind.104 nonaffected first-degree relatives of patients with NSCL/P were recruited in the Multidisciplinary Cleft Clinic of the University Hospitals Leuven, Belgium, together with 37 control persons with a negative familial history for NSCL/P, recruited at the outpatient clinic of the University Hospitals Leuven. All relatives and control subjects were European in order to exclude ethnicity effects on the facial morphology of these study subjects. Exclusion criteria were based on age below 16 years and a history of structural or inflammatory rhinological disease. 3D images were taken of all subjects. After correcting for acquisition failures (such as persons with a beard or expression during image acquisition) and inaccuracies, analysis was done on pictures of 88 relatives  and 33 controls . To confirm the results, we repeated the analysis in a set of obligate “carriers,” that is, unaffected relatives who, according to their pedigree, are the link between two affected individuals in different generations  .In this study group, 30 relatives  and 23 controls  consented to undergo additional olfactory testing, reducing the number of study subjects where the relation between smell capacity and facial morphology could be investigated.The work was conducted in accordance with the declaration of Helsinki. All participants have given written informed consent. This prospective study was approved by the Ethical Committee of the University Hospitals Leuven and Catholic University Leuven, Belgium, and is known as study ML8636.Data acquisition was done using a two-pod 3dMDface imaging system . This is a commercially available system with a short acquisition time (<1 s) and highly accurate texture and shape outcome. Subjects were asked to have a neutral look on their face and with their mouth closed when photographed. A 3D facial image consists of a spatially dense set of 3D points, connected to each other to form a wireframe that completely represents the 3D facial form . The preOlfactory testing was performed using the extended Sniffin' Sticks test battery , with bilateral presentation of the sticks. Odor threshold for n-butanol (16 dilutions of 4% n-butanol) was done using a triple-forced choice procedure. Threshold was defined as the mean of the last four out of seven staircase reversal points. In the odor discrimination test, triplets of sticks were presented in a randomized order. The subject had to determine the one pen in the triplet that contains a different odor. Odor identification was done by 16 odors. Subjects had to identify the odor out of a list of four possibilities. Combining these three results, a TDI  score was calculated. A subject was considered to be normosmic with a TDI score above 30.5. The cutoff value between hyposmia and anosmia was a TDI score of 16.5. For the correlation between facial morphology and olfactory capacity, the continuous identification score was used instead of the TDI categories. This identification score was corrected for age and sex, through the normative curves, available in the test manual.x-coordinate [The 3D images were exported from the 3dMD Patient software in OBJ format and subsequently imported into an in-house software program developed in MEVISLAB (version 2.6a). The images were purified by removing hair and ears. In the analysis of the facial endophenotype, group membership (relative or control) was coded as a categorical variable in the regression model. In the analysis of the olfactory deficiency and its effect on facial shape, identification scores were used as a continuous variable. An anthropometric mask was nonrigidly mapped onto the original images and their reflections , which wordinate , 23. Theordinate , which wordinate . As an iordinate . This reordinate .Next, the quality of the mapped images was assessed; only images with good enough quality were included in this study (121 of the 141 3D images). The resulting mapped images were exported in OBJ format to MATLAB (version R2012b), where the rest of the analyses were performed.Shape is defined as “all the geometric information that remains when location, scale, and rotational effects are filtered out from an object” . TherefoIn geometric morphometrics, shape regression is a useful technique to investigate the effect of an independent variable of interest/or a certain factor on shape variations. Following previous work dealing with spatially dense shape representations , we usedR2. As such, a localized partial R2 value per quasi-landmark could be obtained [The effect on facial shape of a variable of interest is coded in the partial regression coefficients and the significance thereof is tested following the permutation framework for partial regression coefficients described in . Within obtained . Statistobtained . The locobtained . Subsequobtained . When a 2 test, using the statistical software package GraphPad Prism 5.Results of the olfactory testing were compared by a Chi3D pictures of 88 nonaffected first-degree relatives of patients with NSCL/P and 33 control subjects with a negative familial history for NSCL/P were compared. A significant effect was seen in the upper lip region and at the eyes Figures . This efp = 0.04)  .The relation between olfactory function and facial shape was investigated within the group of nonaffected first-degree relatives. Inclusion of the control group was not done for two reasons: first of all, the control group expressed almost no variation in the smell test outcomes and would therefore dominate the upper scale of smelling values in the olfactory correlation analysis; second, the endophenotypic effect on facial features would contaminate the analysis, such that facial characteristics related to variation in smelling cannot be extracted independent thereof. A significant effect was seen in the relatives with hyposmia in the upper nasal area , with a NSCL/P is one of the most frequent congenital conditions, with an etiology that remains incompletely understood. A possible approach to make progress is the identification of endophenotypes. The gene that is responsible for the endophenotype can be causal for the CL/P phenotype or can be in linkage disequilibrium with (one of) the genes responsible for the condition. The endophenotype can thus help to identify candidate loci for disease-specific genes . It is hFacial anthropometrics, which deals with the objective measurement or quantification of facial morphology in humans, can be done in different ways depending on the data carrier (measuring directly on the subject versus indirectly using 2D and 3D images) and the type of subsequent shape analysis  that is used. A common factor in most methods is the identification of facial landmarks, which introduces a perceptual and subjective bias in the choice of landmarks. This in turn can lead to contrasting study outcomes . FurtherFocusing on the results for the facial endophenotype, both midface retrusion and an excess interorbital width or hypertelorism were observed, which are two facial characteristics that have also been identified in related studies . In a stWith the focus on olfactory dysfunction, reduced smell capacity was described in boys with isolated cleft palate  and a hiWe also looked at the correlation between facial shape and olfactory dysfunction in relatives of patients with NSCL/P, and a smaller nasal bridge in relatives with olfactory dysfunction was observed. This coincides with the position of the olfactory bulb and is consistent with the observation that hyposmia and anosmia are associated with hypoplasia of the olfactory bulb –41. To cAlthough future work and bigger shape sample sizes are required to confirm the hypothesis, both facial analyses within this study combined show an interesting aspect. Hypertelorism was found as an endophenotype when comparing controls against first-degree relatives. At the same time, when analyzing facial shape in first-degree relatives only in function of olfactory dysfunction, variation of the extent of hypertelorism is observed. This variation is related to variation in the nasal bridge where the olfactory bulb is located as previously discussed. A subset of relatives who display an olfactory dysfunction show a smaller interorbicular region, compared to relatives with a normal smell capacity and are thus not showing the same degree of hypertelorism. This could indicate a distinct genetic pathway in the genetic etiology of NSCL/P. Indeed, multiple genes are known to play a role in the genetic etiology of NSCL/P. The fact that the subgroup of hyposmic relatives has a different facial phenotype suggests that the biological pathway resulting in a fusion deficit of the facial prominences in their offspring is different. Cleft lip and cleft palate are indeed a genetically heterogeneous disorder. Defining more homogenous subgroups as is done in this study may allow for a better understanding of the genetic etiology in future. Different susceptibility genes may increase the chance of nonfusion of the maxillary and medial nasal prominences during embryogenesis via different biological pathways. It is known that the facial development is indeed prone to many factors and many genes are involved. Further research is therefore necessary to identify the causal genes for the different endophenotypes and the relationships between them.Nonaffected first-degree relatives of patients with NSCL/P show midface retrusion, hypertelorism, and a reduced smell capacity, compared to a control group with a negative familial history for NSCL/P. This work therefore replicates previous identified endophenotypes. Furthermore, a smaller upper nasal region is seen in relatives with olfactory dysfunction, indicating a smaller central olfactory region. This publication is the first to investigate the relationship between the facial and olfactory endophenotypes. Further research is necessary to investigate the central olfactory structures in patients with NSCL/P and their nonaffected first-degree relatives. Large association studies are necessary to identify new susceptibility genes for NSCL/P and to investigate the involvement of different pathways in the genetic etiology of NSCL/P.


Background: Genome-wide association studies (GWAS) found that IGF2BP2 rs4402960 and rs1470579 polymorphisms were associated with type 2 diabetes mellitus (T2DM) risk. Many studies have replicated this association, but yielded inconsistent results. Materials and Methods: A case-control study consisting of 461 T2DM patients and 434 health controls was conducted to detect the genetic susceptibility of IGF2BP2 in a northern Han Chinese population. A meta-analysis was to evaluate the association more precisely in Asians. Results: In the case-control study, the carriers of TT genotype at rs4402960 had a higher T2DM risk than the G carriers (TG + GG) (adjusted odd ratio (AOR) = 1.962, 95% confidence interval (95% CI) = 1.065–3.612, p = 0.031]; CC carriers at rs1470579 were more susceptible to T2DM than A carriers (CA + AA) . The meta-analysis containing 36 studies demonstrated that the two polymorphisms were associated with T2DM under the allele comparison, genetic models of dominant and recessive in Asians (p < 0.05). The rs4402960 polymorphisms were significantly associated with the T2DM risk after stratification by diagnostic criterion, size of sample and average age and BMI of cases, while there’re no consistent results for rs1470579. Conclusions: Our data suggests that IGF2BP2 polymorphisms are associated with T2DM in Asian populations. The rapidly increasing prevalence of type 2 diabetes mellitus (T2DM) is identified as a major international health concern, with a great impact on global morbidity and premature mortality, not to mention the pressure on society and the economy of its chronic complications . In ChinIGF2BP2) and risk of T2DM was founded by the study group of the Wellcome Trust Case Control Consortium (WTCCC), IGF2BP2 has been identified as a notable T2DM candidate gene [T2DM is a complex metabolic syndrome with a strong genetic component, which plays a role in the initiation and development of T2DM ,4. Over ate gene ,7,8.IGF2BP2 is located on chromosome 3q27 [IGF2BP2, highly expressed in pancreatic islets, belongs to a family of the insulin-like growth factor 2 (IGF2) mRNA-binding proteins, which play roles in normal embryonic growth and development [IGF2BP2 has been found to be associated with decreased insulin secretion, which plays a role in T2DM [et al. stated that rs4402960 and rs1470579 of IGF2BP2 gene associated with T2DM susceptibility by a comprehensive genetic association research [et al. reported no association of the single nucleotide polymorphisms (SNPs) with diabetes in a Han Chinese population [elopment . Moreove in T2DM . Duesingresearch . Howeverpulation . Moreovepulation ,14,15,16IGF2BP2 gene polymorphisms and T2DM in a group of northern Han Chinese subjects followed by a meta-analysis in the Asian population.The risk allele frequencies of the T2DM susceptible locus are different among populations, for example distributions of T allele in rs4402960 are 35% in Asians and 30% in Caucasians. In addition, the insufficient power and small effect of the polymorphisms on T2DM risk may explain to some degree the inconclusive results. In an effort to arrive at a more definitive conclusion, we conducted a case-control study to analyze the associations between rs4402960 and rs1470579 of the The present study was conducted in accordance with the Declaration of Helsinki guidelines. Written informed consents were obtained from all the participants. The study was approved by the Ethics Committee of Capital Medical University . In this case-control study, 461 T2DM-diagnosed patients and 434 controls were recruited at the Jidong Oil Field Hospital  from January 2009 to October 2013. The T2DM patients were diagnosed and confirmed by the American Diabetes Association criteria  or had aGenomic DNA was extracted from peripheral white blood cells using blood genome DNA extraction kits according to the manufacturer’s instructions . SNPs were genotyped by matrix assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) using a Mass ARRAY system . The call rates for the genotyping of the SNPs were >95%. In order to verify whether there was genotyping error, we randomly selected 40 samples for each SNP, and verified the genotype using Sanger sequencing.2).Data were collected by a comprehensive review of hospital records, including fasting plasma glucose (FPG), triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), systolic blood pressure (SBP), diastolic blood pressure (DBP) and uric acid (UA), which were all tested through standard ways in the clinical laboratory of the Jidong Oil Field Hospital . Weight t test was used to test between-group differences for continuous variables. Chi-square test was applied for categorical variables. Gene-disease associations were measured using odds ratios (ORs), 95% confidence interval (95% CI) and p value derived from unconditional logistic regression (ULR) analyses adjusted for age, sex and BMI. Individuals homozygous for the risk allele (R/R), heterozygous (R/r) and homozygous for the non-risk allele (r/r) were assigned a categorical variable according to genotypes. The dominant model was defined as R/R + R/r versus r/r, and the recessive model as R/R versus R/r + r/r.Analyses were conducted with SPSS Software V.18.0 . Continuous variables were presented as mean ± standard deviation (SD). Categorical variables were presented as numbers and percentages. Student’s p < 0.05 (two-tailed).The Haploview program 4.2 was used to calculate pairwise linkage disequilibrium (LD) statistics and examine haplotype associations with T2DM. Chi-square test was used to test Hardy-Weinberg equilibrium (HWE) for genotype frequencies. The significance level was set at IGF2BP2”, “T2DM”, “T2D”, rs4402960, rs1470579. Eligible studies had to meet all of the criteria as follows: (1) in case–control or cohort study design; (2) detailed allele frequencies and genotype data for rs4402960, rs1470579 with T2DM risk in Asian populations. The major exclusive criteria:(1) incomplete or duplicate data; (2) meta-analyses and review articles.Genetic association studies published before the end of December 2015 were identified through a search of PubMed, EMBASE, ISI Web of Science, Wanfang and Chinese National Knowledge Infrastructure (CNKI). The key words of our search included “IGF2BP2 polymorphisms and the risk of T2DM based on the genetic inheritance models described as before. The Z-test was used to test the significance of the pooled OR. Subgroup analyses were performed according to the criterion of diagnostic  or others), sample size (case samples <500 or >500), and mean BMI (<25 kg/m2 or 25–30 kg/m2) and age of cases. Heterogeneity between studies was evaluated with the I2 test and the Q statistic [I2 > 50% or p < 0.10 for Q statistics was considered as significant heterogeneity. Upon the existence of heterogeneity, either the random-effect model or fixed-effect model would be adopted. Sensitivity analyses were performed for the effect of included individual researches and the assessment of the results stability. Funnel plots represented publication bias graphically [p < 0.05 (two-tailed). Analyses were conducted with the Review Manager 5.0 .According to the meta-analysis following Observation Studies in Epidemiology (MOOSE) standards, data were independently extracted from all genetic association studies independently by two authors . Any distatistic . I2 > 50phically . The sigp < 0.05)  patients, and 249 male and 185 female (51.82 ± 12.67 years) controls were included in the final analysis. T2DM patients had significantly higher BMI, FPG, TG, TC, LDL-C, SBP, DBP than health controls ( < 0.05) .In order to verify whether there was genotyping error, PCR and Sanger sequencing were performed for randomly selected 40 samples. The Sanger sequencing data was consisted with MALDI-TOF MS sequencing data .p = 0.088; rs1470579 HW-p = 0.052). The genotype and allele frequencies of the rs4402960 and rs1470579 were similar in T2DM and control groups (p > 0.05). In the recessive model, the carriers of TT at rs4402960 had a higher risk of T2DM compared to the carriers of TG + GG (adjusted odds ratio (AOR) = 1.962, 95% CI = 1.065–3.612, p = 0.031); the carriers of CC at rs1470579 were more susceptible to T2DM than the carriers of CA + AA . There was no statistical significance found in the dominant model of the rs4402960 and rs1470579 (p > 0.05). The two SNPs are in strong LD (D′ = 1 and r2 = 0.9). There was no statistical significant association of haplotype with T2DM . In the stratified analysis by ethnicity, significantly increased risks were found among Chinese and Japanese populations (p < 0.05). However, no significant associations were found in Indian and Korean populations under the recessive model and among other ethnic populations (p > 0.05). In the stratified analysis by diagnostic criterion, sample size and average age and BMI of cases, significant associations were identified for rs4402960 in all genetic models (The significant associations between rs4402960 polymorphism of c models .p = 10−5), with corresponding results under dominant and recessive genetic models of 1.11  and 1.21 , respectively. In the stratified analysis by ethnicity, significantly increased risks were found among Chinese and Japanese populations (p < 0.05). No significant associations were found in the Indian populations (p > 0.05). C allele of rs1470579 was also associated with increased T2DM risk, when studies were stratified for diagnostic criterion, size of sample and average BMI of cases (p < 0.05). However, under the dominant model, no significant association was found in the “others” of diagnostic criterion, case samples <500 and 25 ≤ BMI ≤ 30 subgroups (p > 0.05). Under the recessive model, no significant association was found in the 25 ≤ BMI ≤ 30 subgroup (p > 0.05). Upon the research stratification for average age of cases, significant association was not detected in the age <55 subgroup in all genetic models of rs1470579 (p > 0.05)  .Significant heterogeneity was observed for the rs4402960 polymorphism in allele contrast genetic model and for the rs1470579 polymorphism in dominant and recessive genetic models. Thus, the calculation of the pooled OR was based on a random-effects model. A sensitivity analysis was conducted to explore the sources of heterogeneity, when the number of studies ≥10. There was no single research that affected the pooled OR and CIs in a qualitative way. The funnel plot revealed no obvious publication bias .IGF2BP2 polymorphism and T2DM risk have been well investigated in several studies, while the association remained unclear. In this study, we validated the associations in a northern Han Chinese population. Our case-control study showed that rs4402960 and rs1470579 polymorphism associated with risk of T2DM under the recessive genetic models (p < 0.05), with no statistical significance in other models.The associations between IGF2BP2 and T2DM risk in the Asians. The results of meta-analysis revealed that rs4402960 and rs1470579 was significantly associated with susceptibility of T2DM in Asians. Considering small deviation from different genetic models of IGF2BP2 polymorphism, we investigated the associations of the two SNPs with T2DM risk based on dominant and recessive models and also found a significant result [IGF2BP2 polymorphism and T2DM were only found under the recessive genetic models, which could be caused by the small affected genotypes and insufficient statistical power in some models. In addition, some studies showed an association of the IGF2BP2 variant with T2DM under the recessive model [IGF2BP2 (rs4402960 and rs1470579) and T2DM under various models and different populations.When it comes to the problem of small sample sizes and insufficient statistical power, Meta-analysis was usually performed in terms of genetic association studies of complicated diseases . Therefot result . The sigve model ,40, whilve model ,37,51,56In the stratified analysis by ethnicity, statistically significant associations were found in Chinese and Japanese for the rs4402960 and rs1470579 polymorphisms in all genetic models. However, we observed that association between rs4402960 polymorphism and risk for T2DM susceptibility in Japanese populations (OR = 1.18) was stronger than that in Chinese (OR = 1.15). Such result may be due to ethnic differences, since the frequency of T allele in rs4402960 is 0.239 in Chinese, while 0.298 in Japanese. Similar results were also found in rs1470579 polymorphism. No significant associations found in other ethnic populations could be explained by study design or the limited number of studies which had insufficient statistical power to detect a slight effect. The more researches are needed to examine the effect of this variation on T2DM in different ethnic populations.2 and 25–30 kg/m2 studies, suggesting that rs4402960 is an associated factor for T2DM independent of obesity.As for the subgroup analysis based on diagnostic criterion, size of sample and average and BMI of cases, significant associations between rs4402960 and T2DM were consisted among all genetic models. The large studies usually dominate the meta-analysis, while the effect of studies with small sample is apparently decreased . In our IGF2BP2. The association needs to be verified in more studies with larger sample size and prospective study in the future.For rs1470579, the study showed inconsistent association and significant heterogeneity among the stratified analysis, might resulting from the limited amount of studies available. Older age is risk factor for T2DM . We founIGF2BP2, a significant signaling molecule for growth and insulin, has been found have effect on pancreatic development in animal models [et al. stated that the higher levels of FPG, postprandial serum insulin and TC were founded among T2DM patients who carried the C allele of rs1470579 compared with AA carriers [IGF2BP2 play role in the regulation of pancreatic beta-cell function [IGF2BP2 [DGKG) located closed to IGF2BP2, has been reported associated with metabolic regulation [IGF2BP2 are warranted.l models ,64. Huancarriers . Rs44029carriers . Similarcarriers ,65,66. Tfunction . Since tgulation . TherefoSome limitations still existed in the present analysis. Firstly, the study is based on the design of case-control, which restricted the cause-effect inference. The cohort studies are required for the further consequence confirmation. Secondly, only the sample size and allele frequency were available in some of the included studies. Therefore we exhibited the wt/mutant allele numbers in cases and controls in the pooled data, instead of the genotype information. Thirdly, there was still heterogeneity in the subgroup analysis. The more confounding factors should be considering. Fourthly, numerous environmental, genetic factors and the interactions among these factors contribute to the progression of T2DM. Our meta-analysis results did not adjust any confounding covariant, for example gender, drinking status, smoking habit. A more comprehensive analysis should be conducted when more original information is available and interactions among the risk factors are considered.IGF2BP2 on T2DM under different genetic models, and we confirmed the association between rs4402960 and rs1470579 (IGF2BP2) and T2DM under the recessive model in a northern Han Chinese population. Meta-analysis indicated significant contributions of IGF2BP2 gene rs4402960 and rs1470579 polymorphisms to T2DM in Asian populations.In conclusion, we detected the genetic susceptibility of


MTHFR 677C>T, MTRR 66A>G, and RFC1 80G>A, are likely to act as maternal risk factors for the birth of a child with trisomy 21, revealing also complex gene-nutrient interactions. A large-cohort study also revealed that lack of maternal folic acid supplementation at peri-conception resulted in increased risk for a DS birth due to errors occurred at maternal meiosis II in the aging oocyte, and it was shown that the methylation status of chromosome 21 peri-centromeric regions could favor recombination errors during meiosis leading to its malsegregation. In this regard, two recent case-control studies revealed association of maternal polymorphisms or haplotypes of the DNMT3B gene, coding for an enzyme required for the regulation of DNA methylation at centromeric and peri-centromeric regions of human chromosomes, with risk of having a birth with DS. Furthermore, congenital heart defects (CHD) are found in almost a half of DS births, and increasing evidence points to a possible contribution of lack of folic acid supplementation at peri-conception, maternal polymorphisms of folate pathway genes, and resulting epigenetic modifications of several genes, at the basis of their occurrence. This review summarizes available case-control studies and literature meta-analyses in order to provide a critical and up to date overview of what we currently know in this field.Almost 15 years ago it was hypothesized that polymorphisms of genes encoding enzymes involved in folate metabolism could lead to aberrant methylation of peri-centromeric regions of chromosome 21, favoring its abnormal segregation during maternal meiosis. Subsequently, more than 50 small case-control studies investigated whether or not maternal polymorphisms of folate pathway genes could be risk factors for the birth of a child with Down syndrome (DS), yielding conflicting and inconclusive results. However, recent meta-analyses of those studies suggest that at least three of those polymorphisms, namely  Dietaryt Figure . Therefot Figure . Folic at Figure . An overSLC19A1 gene (commonly known as RFC1 gene)  is the main form of circulating folate in the plasma and can be transported into the cells by means of folate carriers and receptors, one the best characterized being the ubiquitously expressed reduced folate carrier (RFC), coded by the Intracellularly, 5-methylTHF functions as a methyl donor for homocysteine (hcy) remethylation, a reaction catalyzed by the methionine synthase (MTR) enzyme that transfers a methyl group from 5-methylTHF to hcy, forming tetrahydrofolate (THF) and methionine. Cobalamin (vitamin B12) is a cofactor in this reaction and methionine synthase reductase (MTRR) is required for the maintenance of MTR in its active state  by transferring the methyl group to diverse biological acceptors, including proteins and DNA. When the DNA is the final acceptor of the methyl group, the reaction is catalyzed by DNA methyltransferases (DNMTs). SAH is then converted to hcy and adenosine by SAH hydrosylase  . Depending on cellular demands, 5,10-methyleneTHF can be used for thymidylate synthesis, for purine synthesis, or for the production of 5-methylTHF required for hcy remethylation reactions  during fetal development, undergo DNA replication and homologous recombination, and then remain arrested in prophase I (dictyotene stage) for several years until ovulation. Meiosis II (MII) is completed only after fertilization that can occur from almost 13 to more than 40 years after the initiation of meiosis I. Advanced maternal age at conception and impaired chromosome 21 recombination represent the two best-known maternal risk factors for chromosome 21 non-disjunction , resulting in Ala222Val amino acid substitution, is known to reduce enzyme activity. Indeed, MTHFR works as a dimer protein that is stabilized by physiological levels of folate, and the MTHFR 677T allele renders the enzyme thermolabile, particularly in homozygous TT individuals that are prone to dimer destabilization under conditions of reduced folate bioavailability  with respect to control mothers, and that paper opened the way to the study of folate gene polymorphisms as maternal risk factors for the birth of a child with DS , followed by Brazilians (ranging from 33.5 to 33.9%), and lower in Asian populations (ranging from 20.0 to 32.3%) , followed by tropical regions (only CT vs. CC carriers), but no significant effect was observed for those living in northern regions of the globe  to detect aneuploidy , results in a Glu429Ala aminoacidic change and is in linkage disequilibrium with the MTHFR 677C>T one. Particularly, the MTHFR 677T-1298C haplotype is rare, and the double homozygous 677TT-1298CC genotype leads to MTHFR protein instability and inactivity, often resulting in prenatal death , followed by Caucasians (33.0–35.0%) and Brazilians (23.0–25.0%) , resulting in Ile22Met amino acid change, was the second polymorphism of the folate pathway, after the MTHFR 677C>T one, to be associated with the maternal risk of having a birth with DS in North American women  resulting in Ser175Leu replacement, has been linked to the maternal risk of birth of a child with DS , leading to the Asp919Gly substitution, was the third variant of the folate pathway to be associated with the maternal risk of having a birth with DS  concentrations, an indicator of the vitamin B12 status, in Brazilian women , resulting in Arg27His replacement, was suggested to alter folate uptake, and the combined RFC1 80GG/MTHFR 677TT genotype was associated with increased plasma hcy levels /MTHFR 1298AA genotypes  than in Asian ones (36.0–36.5%)  that results in the duplication of a splice site at the intron7/exon 8 junction of the gene , leading to Arg653Gln, reduces enzyme stability and activity and was first investigated as a maternal risk factor for trisomy 21 in Southern Italian women, showing association with DS risk in combination with the RFC1 80G>A polymorphism (the combined MTHFD1 1958AA/RFC1 80GG genotype) , results in Arg232Pro replacement and impairs cobalamin metabolism    leading to Ile23Val substitution, was investigated only in Brazilian women and showed no association with maternal risk for a DS birth  Figure . A commoSHMT, TYMS, and DHFR have been investigated only in one case-control study each , that results in Leu474Phe replacement and impairs SHMT nuclear transport and subsequent thymidilate synthesis  genotyped 105 MDS and 185 control mothers from Brazil for the presence of a 19-bp ins/del polymorphism (rs70991108) that was previously linked to alterations in folate metabolism  leads to Arg239Gln substitution and to a slight reduction in enzyme kinetics, that however do not appear to alter circulating hcy levels  and -579G>T (rs1569686), are in strong linkage disequilibrium, give rise to functional haplotypes that could impair protein expression levels, and have been associated to various kinds of human cancers  which have been linked to the maternal risk for the birth of a child with DS by literature meta-analyses (Table MTHFR 1298A>C and MTRR 524C>T), have been associated with hematochemical markers of one-carbon metabolism  and 149 mothers of a DS child without CHD. The authors observed that MDS carriers of the MTHFR 677CT or TT genotype had an increased risk for DS-CHD in the offspring . However, when MDS were stratified according to folic acid supplementation at peri-conception, the risk for DS-CHD remained significant only in those with MTHFR 677CT or TT genotype that did not take folic acid supplements , but was lost in those MDS that used folic acid supplements at peri-conception . No association with DS-CHD risk was observed for the MTHFR 1298A>C polymorphism  canal compared to control mothers . Collectively those papers are conflicting but four out of five of them (Brandalize et al., Several congenital complications are observed in individuals with DS (for a review see Weijerman and de Winter, MTHFR 677C>T and MTRR 66A>G polymorphisms with CHD risk in the offspring (Wang et al., Despite that a meta-analysis of the few studies of DS-CHD is yet not possible due to their relatively small number Table , a recenIn this regard, Obermann-Borst et al.  performeMTHFR 677C>T, MTRR 66A>G, and RFC1 80G>A, could act as weak independent maternal risk factors for having a child with DS, with slight differences among populations likely due to the existence of complex gene-gene and gene-environment interactions (Table MTHFR 677C>T polymorphism for which data on over 3.000 MDS and almost 5.000 control mothers were available for meta-analysis (Rai et al., Despite that DS occurs in almost 1 on 700 live births, the molecular mechanisms leading to maternal chromosome 21 malsegregation during oogenesis are still not fully understood. Since 1999, it was suggested that maternal polymorphisms in folate pathway genes could contribute to the epigenetic regulation of the chromatin structure in those regions, thus acting as maternal risk factors for the birth of a child with DS (James et al., in utero, impaired growth and, if the birth is reached, to epigenetic changes of several genes likely contributing to the onset of either congenital defects or other diseases in adult-life (Martínez-Frías et al., MTHFR polymorphisms could account also for the occurrence of congenital gastrointestinal disease in DS births observing no association (Table in utero exposure is still unclear.Furthermore, overexpression of folate pathway genes mapping to chromosome 21 in a developing DS embryo could result in a different requirement of dietary folates with respect to a normal embryo and, if not properly provided by the maternal diet, could contribute to death on Table , but theon Table . Similaron Table , but alson Table  or accelon Table , but howin utero or to the occurrence of either congenital or age-related DS comorbidities.In conclusion, the available literature in this field suggests that it is now time for the design of large-scale prospective studies, spanning over at least three different generations, in order to clarify the possible contribution of both maternal and maternal grandmother's diet and genotype to the occurrence of meiotic errors favoring chromosome 21 malsegregation and the birth of a DS child, as well as to other metabolic changes and/or epigenetic modifications leading to death The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.