Associations of insulin receptor and insulin receptor substrates genetic polymorphisms with polycystic ovary syndrome: A systematic review and meta-analysis

Custom exome panel revealed new mutations in MAPK14 and novel mutation in RUNX2 gene in patients with PCOS

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy and is both phenotypically and genotypically heterogeneous. A large number of genetic variants have been found in different genes, so far. Based on the literature, we identified 7 genes and aimed to find new causative variants in these genes. We created a targeted PCOS panel including major genes in the steroidogenezis, WNT, MAPK, and TGFβ pathways and analyzed whole-exome sequencing results. We compared the minor allele frequency (MAF) values of different variants with our results and calculated deleterious scores of newly found variants using various web-based prediction tools and ACMG pathogenicity criteria. We found a novel missense mutation (p.Thr355Ile) in the RUNX2 gene in one patient and heterozygous mutations in the MAPK14 gene (c.306_5delT and c.*8G > T) in another patient with PCOS. Five novel pathogenic moderate (PM2) intronic variants in 4 different genes in total were introduced for the first time. We also decoded 7 genes in patients with PCOS in our cohort. Two more candidate genes (MAPK14 and RUNX2) may be related to PCOS.

Association of Gene Polymorphisms with Polycystic Ovary Syndrome: A Meta-analysis

Objectives

Polycystic ovary syndrome (PCOS) is a prevalent endocrine-metabolic disorder affecting reproductive-aged women. Genetic factors play a significant role in its development. This meta-analysis assesses the associations between specific gene polymorphisms (Vitamin D receptor [VDR] and adiponectin [ADIPOQ]) and PCOS susceptibility.

Materials and Methods

We conducted a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Collecting data from published articles between 2013 to 2013. Eligible studies were selected based on inclusion and exclusion criteria, with quality assessment performed using the Newcastle-Ottawa scale. Data were extracted, and statistical analyses included odds ratios with 95% confidence intervals for gene polymorphisms. Heterogeneity was evaluated using I 2 tests, and publication bias was assessed using Begg's and Egger's tests.

Results

A total of 33 articles involving 5677 cases and 5257 controls were included in the analysis. Significant associations were observed for VDR TaqI rs731236 polymorphism in the dominant and recessive models and VDR BsmI rs1544410 polymorphism in the dominant and recessive models. For ADIPOQ T45G rs2241766, a significant association was found in the heterozygous model. The results did not reveal any significant associations for ADIPOQ G276T rs1501299.

Conclusion

This meta-analysis suggests associations between specific gene polymorphisms (VDR and ADIPOQ) and PCOS susceptibility. Further research is needed to validate these findings and unravel the complex genetic factors contributing to PCOS, potentially leading to improved diagnostic and therapeutic strategies.

The Value IRS-1 rs1801278G > A Polymorphism Testing in Evaluating Infertile Women with Polycystic Ovarian Syndrome: A Case-control Study

Background:

Polycystic ovary syndrome (PCOS) is a leading cause of infertility. Insulin resistance is a key element in pathogenesis. The insulin receptor causes phosphorylation of the insulin receptor substrate (IRS); IRS-1 rs1801278G > A polymorphism variant is the most common genetic variant associated with IR and PCOS.

Objective:

We aimed to examine the frequency of IRS-1 rs1801278G > A polymorphism variant and test its value in evaluating infertile PCOS women.

Methods:

A case-control study recruited 140 age and body-mass-matched participants in the university hospital, subdivided according to Rotterdam criteria into PCOS cases (70/140) and healthy controls (70/140). We collected demographic data, ultrasonic [antral follicles and endometrial thickness], hormonal [FSH, LH, AMH, E2], and genetic data by polymerase chain reaction for analysis.

Result:

Wild GG SNP rs1801278 G was meaningfully higher among controls (58.57%, P<0.0001). Mutant AA SNP rs1801278 was significantly higher in PCOS women (37.14%, P-value =0.0001, an odds ratio of 20.50, 95% CI (9.42-28.63) to develop PCOS. Heterogenous GA gene SNP rs1801278 showed a trend of higher frequency in PCOS patients with 44.29%; OR of 3.91, 95% CI (1.37–7.55); P = 0.422. Upon correlating infertility parameters to SNP rs1801278 G>A polymorphism, statistical differences were found with AFC, LH/FSH ratio, and serum testosterone. As for the AMH, E2, and endometrial thickness, they failed to have a statistical value.

Conclusion:

The significant correlation of genetic polymorphism to infertility parameters among PCOS women opens a new therapeutic and prognostic avenue that helps gynecologists tailor manganate for a better and safer outcome.

Insulin Receptor Substrate 1 Gly972Arg (rs1801278) Polymorphism Is Associated with Obesity and Insulin Resistance in Kashmiri Women with Polycystic Ovary Syndrome

Background: Polycystic ovary syndrome (PCOS) is commonly associated with metabolic abnormalities such as hyperinsulinemia, insulin resistance and obesity. The genetic variants of genes regulating insulin action, expression and regulation are suggested as possible factors involved in development and severity of clinical manifestations in PCOS. Aim: We investigated whether IRS-1Gly972Arg (rs1801278) polymorphism is associated with increased risk of PCOS in Kashmiri women. The correlation of various clinical, metabolic and hormonal markers with rs1801278 single nucleotide polymorphism was analyzed. The genotypic−phenotypic association of clinical manifestations of PCOS with the tested genetic variant was also assessed. Results: There were no significant differences in allele frequency (OR = 0.87, CI = 0.59−1.29, χ2 = 0.456, p = 0.499) or genotypic distribution (χ2 = 3.73, p = 0.15) between PCOS women and controls. No significant association was also found in the dominant (OR = 1.63, χ2 = 0.377, p = 0.53), recessive (OR = 0.79, χ2 = 1.01, p = 0.31) or heterozygote vs. homozygote (OR = 1.34, χ2 = 1.53, p = 0.22) genotype model analysis. The genotype−phenotype correlation analysis showed that the Arg allele was significantly associated with increased central adiposity markers hip circumference (p = 0.012), and body adiposity index BAI (p = 0.002) in the recessive model in PCOS women. The two-hour glucose (p = 0.04) and insulin resistance marker HOMA (p = 0.44) were significantly higher in Arg allele carriers. The androgen excess markers dehydroepiandrosterone sulfate DHEAS (p = 0.02), Ferriman−Gallwey score (p = 0.012), prevalence of acne, alopecia and hirsutism (all p < 0.01) were significantly elevated in the wild-type GG genotype. Conclusions:IRS-1Gly972Arg genetic variant does not increase the risk of PCOS in Kashmiri women. However, this polymorphism is associated with clinical manifestations of insulin resistance, obesity and hyperandrogenism, suggesting its possible role in variable phenotypic manifestations of PCOS.

The Insulin Receptor: An Important Target for the Development of Novel Medicines and Pesticides

The insulin receptor (IR) is a transmembrane protein that is activated by ligands in insulin signaling pathways. The IR has been considered as a novel therapeutic target for clinical intervention, considering the overexpression of its protein and A-isoform in multiple cancers, Alzheimer's disease, and Type 2 diabetes mellitus in humans. Meanwhile, it may also serve as a potential target in pest management due to its multiple physiological influences in insects. In this review, we provide an overview of the structural and molecular biology of the IR, functions of IRs in humans and insects, physiological and nonpeptide small molecule modulators of the IR, and the regulating mechanisms of the IR. Xenobiotic compounds and the corresponding insecticidal chemicals functioning on the IR are also discussed. This review is expected to provide useful information for a better understanding of human IR-related diseases, as well as to facilitate the development of novel small-molecule activators and inhibitors of the IR for use as medicines or pesticides.

Single nucleotide polymorphisms in binding site of miRNA-135a and targeted gene IRS2 are correlated with multiple clinical features of PCOS: A study in Chinese women

BACKGROUND:

The etiology of polycystic ovary syndrome (PCOS) remains unclear with highly heterogeneous clinical manifestations, recently growing evidence revealing genetic variants play a crucial part in its pathogenesis.

OBJECTIVE:

This study aimed to examine the correlation between SNPs in miRNA-135a’s binding site of targeted gene IRS2 and clinical manifestations of PCOS in Chinese females.

METHOD:

A total of 126 Chinese women with PCOS and 109 healthy women were enrolled, divided into 4 groups based on different clinical features of hyperandrogenemia (HA), insulin resistance (IR), polycystic ovary morphology (PCOM) and obesity. We analyzed 2 single nucleotide polymorphisms (SNPs) of the IRS2 gene (rs2289046 and rs1865434) and clinical features’ laboratory measurements such as sex hormone, fasting plasma glucose (FPG), fasting plasma insulin (FINS).

RESULTS:

Located in miRNA-135a binding site of IRS2 gene, the rs2289046’s triple genotypes distribution showed a significant difference between PCOS/control group and PCOM/non-PCOM group (P< 0.05) while the rs1865434’s triple genotype distribution showed a significant difference between obesity/non-obesity group (P< 0.05).

CONCLUSION:

The results revealed the two SNPs as rs2289046 and rs1865434 in the IRS-2 binding region of miRNA-135a have correlations with the clinical features of PCOS in Chinese population.

An update on polycystic ovary syndrome: A review of the current state of knowledge in diagnosis, genetic etiology, and emerging treatment options

Polycystic ovary syndrome is the most common endocrine disorder in women of reproductive age, which is still incurable. However, the symptoms can be successfully managed with proper medication and lifestyle interventions. Despite its prevalence, little is known about its etiology. In this review article, the up-to-date diagnostic features and parameters recommended on the grounds of evidence-based data and different guidelines are explored. The ambiguity and insufficiency of data when diagnosing adolescent women have been put under special focus. We look at some of the most recent research done to establish relationships between different gene polymorphisms with polycystic ovary syndrome in various populations along with the underestimated impact of environmental factors like endocrine-disrupting chemicals on the reproductive health of these women. Furthermore, the article concludes with existing treatments options and the scopes for advancement in the near future. Various therapies have been considered as potential treatment through multiple randomized controlled studies, and clinical trials conducted over the years are described in this article. Standard therapies ranging from metformin to newly found alternatives based on vitamin D and gut microbiota could shine some light and guidance toward a permanent cure for this female reproductive health issue in the future.

Genetic Susceptibility to Joint Occurrence of Polycystic Ovary Syndrome and Hashimoto's Thyroiditis: How Far Is Our Understanding?

Polycystic ovary syndrome (PCOS) and Hashimoto’s thyroiditis (HT) are endocrine disorders that commonly occur among young women. A higher prevalence of HT in women with PCOS, relative to healthy individuals, is observed consistently. Combined occurrence of both diseases is associated with a higher risk of severe metabolic and reproductive complications. Genetic factors strongly impact the pathogenesis of both PCOS and HT and several susceptibility loci associated with a higher risk of both disorders have been identified. Furthermore, some candidate gene polymorphisms are thought to be functionally relevant; however, few genetic variants are proposed to be causally associated with the incidence of both disorders together.

microRNA-103 Contributes to Progression of Polycystic Ovary Syndrome Through Modulating the IRS1/PI3K/AKT Signal Axis

BACKGROUND

Polycystic ovary syndrome (PCOS) is a frequent gynecological endocrine disorder, and the majority of PCOS patients experience different degrees of insulin resistance (IR). Nevertheless, the functions of microRNAs (miRNAs) in IR of PCOS remain unclear. In this study, we desired to elucidate the mechanisms of miR-103 in IR of PCOS.

METHODS

The ovarian pathological morphology of established PCOS rats was detected by HE staining. Following miR-103 expression determination in the ovarian tissues of PCOS rats, the relationship between its expression and IR was studied. A PCOS/IR cell model was established, and the effect of miR-103 on granulosa cells was determined by CCK-8 assay and flow cytometry. Through online website prediction and consulting related literatures, the target gene of miR-103 and the pathway regulated by the target genes were discovered, which was verified by further experiments.

RESULTS

PCOS rats showed polycystic changes in the ovary and a decrease in granulosa cells, and these symptoms were more pronounced in rats showed IR. miR-103 expressed highly in PCOS and was positively related to IR. miR-103 inhibitor led to improved PCOS-related symptoms. In addition, miR-103 directly targeted IRS1, which was poorly expressed in PCOS, and IRS1 silencing promoted PCOS development. Furthermore, miR-103 regulated the PI3K/AKT pathway by targeting IRS1, and PI3K/AKT pathway suppression reduced the therapeutic effect of miR-103 inhibitor.

CONCLUSION

This study indicates that miR-103 disrupts the PI3K/AKT pathway activation by targeting IRS1, thereby aggravating PCOS development. miR-103 inhibition may be a promising molecular target for treatment of PCOS.

The roles of ANRIL polymorphisms in coronary artery disease: a meta-analysis

Background: The relationship between antisense non-coding RNA (ncRNA) in the INK4 locus (ANRIL) polymorphisms and coronary artery disease (CAD) remains inconclusive. Thus, we conducted this meta-analysis to better evaluate the roles of ANRIL polymorphisms in CAD. Methods: Systematic literature search of PubMed, Medline, and Embase was performed to identify potential relevant articles. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the strength of association. Results: Fifteen studies were finally enrolled for analyses. Overall analyses suggested that rs1333040 (dominant model: P<0.0001; recessive model: P<0.0001; allele model: P<0.0001), rs1333049 (dominant model: P=0.02; allele model: P=0.02) and rs2383207 (additive model: P=0.004) polymorphisms were significantly associated with the risk of CAD. Further subgroup analyses showed that rs1333040, rs1333049, and rs2383207 polymorphisms were significantly correlated with the risk of CAD in East Asians, rs2383206 and rs10757274 polymorphisms were significantly correlated with the risk of CAD in West Asians, while rs2383206, rs10757274, and rs10757278 polymorphisms were significantly correlated with the risk of CAD in Caucasians. Conclusion: Our findings indicated that rs1333040, rs1333049, rs2383206, rs2383207, rs10757274, and rs10757278 polymorphisms might serve as genetic biomarkers of CAD in certain ethnicities.

Associations Between Common Polymorphisms of CDKN2B-AS and Susceptibility to ASCVD

This meta-analysis was conducted to estimate associations between CDKN2B antisense (CDKN2B-AS) polymorphisms and susceptibility to atherosclerotic cardio-cerebral vascular diseases (ASCVD). A systematic literature research of PubMed, Medline, Web of Science, Embase, and CNKI was performed to identify eligible studies. Overall, 34 studies were included for meta-analyses. Pooled overall analyses showed that rs1333040, rs1333049, rs2383206, and rs2383207 polymorphisms were associated with susceptibility to ASCVD in the whole population. Further analyses by ethnicity revealed that all investigated polymorphisms were associated with susceptibility to ASCVD in East Asians. Moreover, rs2383206, rs2383207, rs10757274, and rs10757278 polymorphisms were associated with susceptibility to ASCVD in West Asians, while rs2383206, rs10757274, and rs10757278 were associated with susceptibility to ASCVD in Caucasians. When we stratified eligible studies by type of disease, positive results were found for all investigated polymorphisms in patients with coronary artery disease (CAD) or myocardial infarction, whereas positive results were only detected for rs2383206 and rs10757274 polymorphisms in patients with ischemic stroke (IS). Our findings suggest that rs1333040, rs1333049, rs2383206, rs2383207, rs10757274, and rs10757278 polymorphisms might serve as genetic biomarkers of CAD, and rs2383206 and rs10757274 polymorphisms might serve as genetic biomarkers of IS.

Targeting Metabolic Consequences of Insulin Resistance in Polycystic Ovary Syndrome by D-chiro-inositol and Emerging Nutraceuticals: A Focused Review

Polycystic ovary syndrome (PCOS) is a complex disorder associated with ovarian dysfunction, infertility, menstrual irregularity, and hormonal impairments. Over the last decade, several studies have shown that some PCOS women have insulin resistance (InsR) and hyperinsulinemia, apart from being overweight or obese. Therefore, a crucial clinical aspect is that PCOS patients might develop glucose intolerance and type 2 diabetes. Insulin-sensitizing drugs have been used as first-line treatment to improve hyperinsulinemia in women with PCOS. Although reducing PCOS symptoms and signs, several used insulin-sensitizer drugs may induce side effects, which reduces compliance. D-chiro-inositol (DCI), which is a naturally occurring stereoisomer of inositol, has been classified as an insulin-sensitizer and seems to mitigate multiple InsR-related metabolic alterations in PCOS with a safe profile. However, according to a multi-targeted design, the supplementation with DCI can be synergistically integrated by combining other potential insulin-sensitizing drugs and/or nutraceuticals. The literature provides the initial support for using several unexplored nutraceutical interventions that may target relevant metabolic abnormalities associated with InsR in PCOS. With a need to promote interest in clinical research, this review aims to discuss the efficacy of DCI and the role of emerging nutraceuticals for managing InsR in PCOS.

Identification of microRNAs that Regulate the MAPK Pathway in Human Cumulus Cells from PCOS Women with Insulin Resistance

Polycystic ovary syndrome (PCOS) is one of the most common gynaecological endocrine disorders, and more than 60% of PCOS patients have varying degrees of insulin resistance (IR). The regulatory role of microRNAs (miRNAs) at post-transcriptional levels in human cumulus cells relating to IR in PCOS remains unclear. In this case-control study, 26 PCOS patients with IR (PCOS-IR) and 24 patients without IR (PCOS-control) were enrolled. We determined the differentially expressed miRNA and mRNA using next-generation sequencing technology, and these miRNAs and mRNAs were validated by quantitative real-time polymerase chain reaction (PCR). These miRNA regulating pathways (e.g., MAPK pathway) were analysed by bioinformatics analysis, and the Rap1b was demonstrated to be targeted by miR-612 based on quantitative real-time PCR, western blot and luciferase activity assay. A total of 59 known miRNAs and 617 differentially expressed genes were identified that differentially expressed between PCOS-IR and PCOS-control cumulus cells. Moreover, the potential regulating roles of miRNAs and their targeting genes in pathophysiology of IR and PCOS were analysed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation, and several key processes were enriched, such as MAPK activity. Furthermore, Rap1b, a regulator of the MAPK pathway, was demonstrated to be suppressed directly by miR-612 in PCOS-IR cumulus cells based on negative expression correlation validation, dual luciferase activity assay and reduction of Rap1b expression after miR-612 mimics transfection. Our results suggested that miRNAs and their targeted pathways in ovarian cumulus cells may play important roles in the aetiology and pathophysiology of PCOS with IR.

A systematic review and meta-analysis of the associations of vitamin D receptor genetic variants with two types of most common neurodegenerative disorders

BACKGROUND

Whether vitamin D receptor (VDR) genetic variants influence individual susceptibility to neurodegenerative disorders remains controversial.

AIMS

This meta-analysis was conducted to analyze correlations of VDR genetic variants with two types of most common neurodegenerative disorders, Parkinson's disease (PD) and Alzheimer's disease (AD).

METHODS

Systematic literature research of PubMed and Embase was performed to identify eligible articles. Q test and I² statistic were employed to decide whether pooled analyses would be performed with random-effect models (REMs) or fixed-effect models (FEMs). All statistical analyses were conducted with Review Manager.

RESULTS

Totally sixteen studies were enrolled for analyses. Among these eligible studies, ten studies were about PD (2356 cases and 2815 controls) and six studies were about AD (1256 cases and 1205 controls). Pooled overall analyses suggested that VDR rs7975232 (additive model: p = 0.03, OR = 1.19, 95% CI 1.01-1.39) and rs2228570 (recessive model: p < 0.008, OR = 1.26, 95% CI 1.06-1.50; allele model: p < 0.001, OR = 0.80, 95% CI 0.71-0.91) variants were significantly correlated with PD, and VDR rs731236 (dominant model: p = 0.003, OR = 0.70, 95% CI 0.56-0.89; additive model: p = 0.02, OR = 1.32, 95% CI 1.06-1.66; allele model: p = 0.02, OR = 0.82, 95% CI 0.69-0.96) variant was significantly correlated with AD. Further subgroup analyses by ethnicity revealed that the positive results were mainly driven by the Asians, whereas no significant associations were observed in Caucasians.

CONCLUSION

Our meta-analysis suggested that VDR rs7975232 and rs2228570 variants might serve as genetic biomarkers of PD, whereas VDR rs731236 variant might serve as a genetic biomarker of AD.

Effects of ADIPOQ polymorphisms on individual susceptibility to coronary artery disease: a meta-analysis

Whether adiponectin (ADIPOQ) polymorphisms affect individual susceptibility to coronary artery disease (CAD) remains controversial. Therefore, we performed this meta-analysis to better analyse associations between ADIPOQ polymorphisms and CAD. PubMed, Web of Science, Embase and CNKI were searched for eligible studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Totally, 51 studies were eligible for analyses. In overall analyses, significant associations with the susceptibility to CAD were detected for rs266729 (overdominant model: p= 0.03, OR = 1.11, 95% CI 1.01–1.22), rs822395 (recessive model: p= 0.007, OR = 1.21, 95% CI 1.05–1.40) and rs2241766 (dominant model: p= 0.0009, OR = 0.82, 95% CI 0.73–0.92; recessive model: p= 0.04, OR = 1.29, 95% CI 1.02–1.64; allele model: p< 0.0001, OR = 0.80, 95% CI 0.73–0.88) polymorphisms. Further subgroup analyses by ethnicity revealed that rs1501299 polymorphism was significantly associated with the susceptibility to CAD in East Asians, while rs2241766 polymorphism was significantly associated with the susceptibility to CAD in Caucasians, East Asians and South Asians. In summary, our findings indicated that rs266729, rs822395, rs1501299 and rs2241766 polymorphisms were all significantly associated with the susceptibility to CAD in certain populations.

Effects of FSHR polymorphisms on premature ovarian insufficiency in human beings: a meta-analysis

BACKGROUND

Whether follicle-stimulating hormone receptor (FSHR) polymorphisms are implicated in premature ovarian insufficiency (POI) remains controversial. Thus, we performed this study to explore correlation between FSHR polymorphisms and POI in human beings.

METHODS

Literature retrieve was conducted in PubMed, Medline, Embase and CNKI. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

Sixteen studies were enrolled for analyses. No significant relationship with POI was found for rs6165 and rs6166 polymorphisms in overall analyses. Further subgroup analyses revealed that rs6166 polymorphism was significantly associated with the risk of POI in Asians with both FEM and REM. Nevertheless, we failed to detect any significant associations with POI for other ethnicities.

CONCLUSIONS

Our findings indicated that FSHR rs6166 polymorphism may serve as a potential genetic biomarker of POI in Asians, but not in other ethnicities.

The Genetics of Polycystic Ovary Syndrome: An Overview of Candidate Gene Systematic Reviews and Genome-Wide Association Studies

Polycystic Ovary Syndrome (PCOS) is a complex condition with mechanisms likely to involve the interaction between genetics and lifestyle. Familial clustering of PCOS symptoms is well documented, providing evidence for a genetic contribution to the condition. This overview aims firstly to systematically summarise the current literature surrounding genetics and PCOS, and secondly, to assess the methodological quality of current systematic reviews and identify limitations. Four databases were searched to identify candidate gene systematic reviews, and quality was assessed with the AMSTAR tool. Genome-wide association studies (GWAS) were identified by a semi structured literature search. Of the candidate gene systematic reviews, 17 were of high to moderate quality and four were of low quality. A total of 19 gene loci have been associated with risk of PCOS in GWAS, and 11 of these have been replicated across two different ancestries. Gene loci were located in the neuroendocrine, metabolic, and reproductive pathways. Overall, the gene loci with the most robust findings were THADA, FSHR, INS-VNTR, and DENND1A, that now require validation. This overview also identified limitations of the current literature and important methodological considerations for future genetic studies. Much work remains to identify causal variants and functional relevance of genes associated with PCOS.

Associations between vitamin D receptor genetic variants and periodontitis: a meta-analysis

Objective: Numerous studies already investigated potential associations between vitamin D receptor (VDR) genetic variants and periodontitis. However, the results of these studies were not consistent. Previous studies failed to reach a consensus regarding associations between VDR variants and periodontitis partially because of their relatively small sample sizes. Thus, we performed the present meta-analysis to explore the relationship between VDR variants and periodontitis in a larger pooled sample size. Material and methods: Systematic literature research was conducted in PubMed, Web of Science, Embase and CNKI to identify eligible case-control studies on associations between VDR variants and periodontitis. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) to estimate the strength of associations in all possible genetic models, and p values ≤.05 were considered to be statistically significant. Results: Totally 30 studies were enrolled for analyses. Pooled analyses suggested that VDR rs2228570 variant was significantly associated with the susceptibility to periodontitis under dominant genetic model in the overall population (p = .03, OR = 0.82, 95%CI: 0.69-0.98, I² = 0). Further subgroup analyses yielded similar positive results for rs2228570 variant in East Asians and patients with chronic periodontitis. Nevertheless, no any other positive findings were observed in overall and subgroup analyses. Conclusions: Our meta-analysis supported that VDR rs2228570 variant might serve as a genetic biomarker of periodontitis. However, further well-designed studies are still warranted to confirm our findings.

A meta-analysis of the relationship between VEGFR2 polymorphisms and atherosclerotic cardiovascular diseases

BACKGROUND

Some previous studies explored associations between vascular endothelial growth factor receptor 2 (VEGFR2) polymorphisms and atherosclerotic cardiovascular diseases (ASCVD), with conflicting findings.

HYPOTHESIS

We thought that VEGFR2 polymorphisms may influence susceptibility to ASCVD. Here, we aimed to better analyze the relationship between VEGFR2 polymorphisms and ASCVD in a larger combined population by performing a meta-analysis.

METHODS

We searched Pubmed, Embase, and Web of Science for related articles. We calculated odds ratio (OR) and 95% confidence interval (CI) to estimate whether there are genetic associations between VEGFR2 polymorphisms and ASCVD.

RESULTS

Ten studies were included for this meta-analysis (5474 cases and 8584 controls). VEGFR2 rs1870377 (dominant comparison: 0.81 (0.73-0.89), I2 = 56%; recessive comparison: 1.40 (1.25-1.57), I2 = 34%; allele comparison: 0.81 (0.76-0.87), I2 = 0%), rs2071559 (dominant comparison: 0.83 (0.76-0.91), I2 = 0%; recessive comparison: 1.22 (1.07-1.38), I2 = 0%; allele comparison: 0.86 (0.81-0.92), I2 = 0%) and rs2305948 (dominant comparison: 0.79 (0.72-0.87), I2 = 25%; recessive comparison: 1.44 (1.08-1.92), I2 = 60%; allele comparison: 0.79 (0.68-0.92), I2 = 73%) polymorphisms were all found to be significantly associated with susceptibility to ASCVD in general population. Subgroup analyses by type of disease revealed similar significant findings for rs1870377, rs2071559, and rs2305948 polymorphisms in coronary artery disease (CAD) subgroup. Besides, positive results were also found for rs1870377 polymorphism in ischemic stroke (IS) subgroup.

CONCLUSIONS

In summary, this meta-analysis proved that these VEGFR2 polymorphisms could be used to identify individual with elevated susceptibility to ASCVD.

LOC643714 Polymorphisms Contribute to an Elevated Susceptibility to Breast Cancer: A Meta-analysis of 231,191 Subjects

BACKGROUND

Several recent genome-wide association studies tried to explore associations between LOC643714 polymorphisms and breast cancer (BC). However, the results of these studies were inconsistent. The purpose of this meta-analysis was to better analyze the effects of LOC643714 polymorphisms on individual susceptibility to BC in a larger pooled population.

MATERIALS AND METHODS

PubMed, Web of Science, and Embase were searched for eligible studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the strength of associations.

RESULTS

In total, 42 studies with 231,191 subjects were analyzed. Significant associations with BC were observed for rs3803662 (dominant comparison: OR, 0.89; 95% CI, 0.84-0.95; P = .0008; recessive comparison: OR, 1.17; 95% CI, 1.07-1.28; P = .0004; over-dominant comparison: OR, 1.07; 95% CI, 1.02-1.11; P = .002; allele comparison: OR, 0.90; 95% CI, 0.86-0.95; P = .0002), rs8051542 (dominant comparison: OR, 0.87; 95% CI, 0.83-0.91; P < .0001; recessive comparison: OR, 1.19; 95% CI, 1.11-1.28; P < .0001; over-dominant comparison: OR, 1.07; 95% CI, 1.02-1.11; P = .004; allele comparison: OR, 0.89; 95% CI, 0.86-0.91; P < .0001), and rs12922061 (dominant comparison: OR, 0.83; 95% CI, 0.73-0.93; P = .002; over-dominant comparison: OR, 1.43; 95% CI, 1.27-1.61; P < .0001) polymorphisms in the overall population. Further subgroup analyses yielded similar positive results for rs3803662 and rs8051542 polymorphisms in Asians, Caucasians, and Africans, for rs12443621 polymorphism in Caucasians, and for rs12922061 polymorphism in Asians.

CONCLUSIONS

Our findings suggested that LOC643714 rs3803662, rs8051542, rs12443621, and rs12922061 polymorphisms were all significantly associated with BC in certain populations.

Correlation Between MTHFR Polymorphisms and Hepatocellular Carcinoma: A Meta-analysis

The correlation between methylenetetrahydrofolate reductase (MTHFR) polymorphisms and hepatocellular carcinoma (HCC) remains controversial. Therefore, we performed this study to better assess the relationship between MTHFR polymorphisms and the likelihood of HCC. A systematic research of PubMed, Medline, and Embase was performed to retrieve relevant articles. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. A total of 15 studies with 8,378 participants were analyzed. In overall analyses, a significant association with the likelihood of HCC was detected for the rs1801131 polymorphism with fixed-effect models in recessive comparison (P = 0.002, OR = 0.62, 95% CI 0.43-0.82). However, no positive results were detected for the rs1801133 polymorphism in any comparison. Further subgroup analyses revealed that the rs1801131 polymorphism was significantly associated with the likelihood of HCC in Asians with both FEMs (recessive model: P < 0.0001, OR = 0.42, 95% CI 0.29-0.62; allele model: P = 0.004, OR =1.20, 95% CI 1.06-1.35) and random-effect models (recessive model: P = 0.002, OR = 0.47, 95% CI 0.29-0.75). Nevertheless, we failed to detect any significant correlation between the rs1801133 polymorphism and HCC. In conclusion, our findings indicated that the rs1801131 polymorphism may serve as a genetic biomarker of HCC in Asians.

Associations of leptin and leptin receptor genetic variants with coronary artery disease: a meta-analysis

Background: Some pilot studies already tried to investigate potential associations of leptin (LEP) and LEP receptor (LEPR) variants with coronary artery disease (CAD). However, the results of these studies were not consistent. Thus, we performed the present meta-analysis to explore associations between LEP/LEPR variants and CAD in a larger pooled population.

Methods: Systematic literature research of PubMed, Web of Science, Embase and CNKI was performed to identify eligible case–control studies on associations between LEP/LEPR variants and CAD. The initial search was conducted in September 2018 and the latest update was performed in December 2018. Q test and I² statistic were employed to assess between-study heterogeneities. If probability value(P-value) of Q test was less than 0.1 or I² was greater than 50%, random-effect models (REMs) would be used to pool the data. Otherwise, fixed-effect models (FEMs) would be applied for synthetic analyses.

Results: A total of ten studies published between 2006 and 2018 were eligible for analyses (1989 cases and 2601 controls). Pooled analyses suggested that LEP rs7799039 variant was significantly associated with CAD under over-dominant model (P=0.0007, odds ratio (OR) = 1.36, 95% confidence interval (CI): 1.14–1.63, I² = 41%, FEM) in overall population, and this significant finding was further confirmed in East Asians in subsequent subgroup analyses. However, no positive findings were observed for LEPR rs1137100 and rs1137101 variants in overall and subgroup analyses.

Conclusions: Our meta-analysis suggested that LEP rs7799039 variant might affect individual susceptibility to CAD.

The rs498872 polymorphism is associated with an elevated susceptibility to glioma: a meta-analysis of 36,264 subjects

Several genome-wide association studies have already explored the associations between rs498872 polymorphism and glioma, but the results of these studies were not consistent. Consequently, we conducted a meta-analysis of relevant studies to better analyze the effects of rs498872 polymorphism on individual susceptibility to glioma. PubMed, Web of Science and Embase were searched for eligible studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Totally, 12 studies with 36,264 subjects were analyzed. A significant association with glioma was observed for the rs498872 polymorphism in CC versus CT + TT (dominant comparison, p < 0.0001, OR = 0.81, 95% CI 0.76-0.85), TT versus CC + CT (recessive comparison, p < 0.0001, OR = 1.23, 95% CI 1.13-1.34), CT versus CC + TT (overdominant comparison, p < 0.0001, OR = 1.15, 95% CI 1.09-1.21) and C versus T (allele comparison, p < 0.0001, OR = 0.86, 95% CI 0.84-0.90). Further subgroup analyses yielded similar positive results in both Asians and Caucasians. Our findings suggested that the rs498872 polymorphism may serve as a potential genetic biomarker of glioma in both Asians and Caucasians.

Associations of intercellular adhesion molecule‐1 rs5498 polymorphism with ischemic stroke: A meta‐analysis

Background

Recently, associations between intercellular adhesion molecule‐1 (ICAM‐1) rs5498 polymorphism and ischemic stroke (IS) were investigated by several pilot studies, but with inconsistent results. In this study, a meta‐analysis was performed to better assess the relationship between ICAM‐1rs5498 polymorphism and IS.

Methods

PubMed, Medline, Embase, and CNKI were searched for eligible studies. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) to evaluate associations between ICAM‐1 rs5498 polymorphism and IS.

Results

Totally 16 studies with 2,596 cases and 11,800 controls were analyzed. A significant association with IS was observed for rs5498 polymorphism in GG versus AA + AG (recessive model, p = 0.009, OR = 1.62, 95% CI 1.13–2.32, I² = 76%) in overall population. Further subgroup analyses showed that rs5498 polymorphism was significantly associated with IS in Caucasians in AA versus AG + GG (dominant model, p = 0.03, OR = 0.52, 95% CI 0.29–0.95, I² = 72%), GG versus AA + AG (recessive model, p < 0.0001, OR = 2.98, 95% CI 2.05–4.31, I² = 19%), and A versus G (allele model, p = 0.005, OR = 0.50, 95% CI 0.31–0.81, I² = 81%). However, no any positive findings were detected for Asians.

Conclusions

Our findings indicated that rs5498 polymorphism was significantly associated with individual susceptibility to IS in Caucasians, but not in Asians.

Effects of ANRIL variants on the risk of ischemic stroke: a meta-analysis

Background: Several studies investigated the relationship between antisense non-coding RNA in the INK4 locus (ANRIL) variants and the risk of ischemic stroke (IS), yet whether ANRIL variants are associated with IS remain controversial. Therefore, we performed the present study to obtain a more conclusive result. Methods: Literature retrieval was conducted in PubMed, Medline and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Results: Eighteen studies were enrolled for analyses. Pooled overall analyses showed that rs2383206 (recessive model: P=0.002, OR = 1.22, 95%CI 1.08–1.38; allele model: P=0.003, OR = 0.90, 95%CI 0.84–0.96) and rs10757274 (allele model: P=0.006, OR = 0.91, 95%CI 0.86–0.97) variants were significantly associated with an increased risk of IS. Further subgroup analyses by ethnicity revealed that rs2383206, rs10757274 and rs10757278 variants were all significantly correlated with an increased risk of IS in Asians. Additionally, rs10757278 polymorphism was also significantly correlated with an increased risk of IS in Caucasians. Conclusions: Our findings indicated that rs2383206, rs10757274 and rs10757278 variants may impact individual susceptibility to IS in Asians. Moreover, rs10757278 polymorphism may also impact individual susceptibility to IS in Caucasians.

Associations between cytotoxic T-lymphocyte-associated antigen 4 gene polymorphisms and diabetes mellitus: a meta-analysis of 76 case-control studies

Background: Several genetic association studies already investigated potential roles of cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) gene polymorphisms in diabetes mellitus (DM), with inconsistent results. Therefore, we performed this meta-analysis to better assess the relationship between CTLA-4 gene polymorphisms and DM in a larger pooled population.

Methods: PubMed, Embase, Web of Science, and CNKI were systematically searched for eligible studies. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate the strength of associations between CTLA-4 gene polymorphisms and DM in all possible genetic models.

Results: A total of 76 studies were finally included in our analyses. Significant associations with susceptibility to type 1 diabetes mellitus (T1DM) were detected for rs231775 (dominant model: P=0.008, OR = 0.83, 95%CI 0.73–0.95; recessive model: P=0.003, OR = 1.27, 95%CI 1.09–1.50; allele model: P=0.004, OR = 0.85, 95%CI 0.77–0.95) and rs5742909 (recessive model: P=0.02, OR = 1.50, 95%CI 1.05–2.13) polymorphisms in overall population. Further subgroup analyses revealed that rs231775 polymorphism was significantly associated with susceptibility to T1DM in Caucasians and South Asians, and rs5742909 polymorphism was significantly associated with susceptibility to T1DM in South Asians. Moreover, rs231775 polymorphism was also found to be significantly associated with susceptibility to type 2 diabetes mellitus (T2DM) in East Asians and South Asians.

Conclusions: Our findings indicated that rs231775 and rs5742909 polymorphisms may serve as genetic biomarkers of T1DM, and rs231775 polymorphism may also serve as a genetic biomarker of T2DM.

Vascular endothelial growth factor gene polymorphisms and hypertensive disorder of pregnancy: A meta-analysis

BACKGROUND

Whether vascular endothelial growth factor (VEGF) polymorphisms affect individual susceptibility to hypertensive disorder of pregnancy remain controversial. Therefore, we performed this meta-analysis to better evaluate associations between VEGF polymorphisms and hypertensive disorder of pregnancy in a larger pooled population.

METHODS

Pubmed, Web of Science, Embase and CNKI were searched for eligible studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

Totally 24 studies were eligible for analyses. In overall analyses, a significant association with hypertensive disorder of pregnancy was observed for rs3025039 polymorphism in dominant (p = 0.01, OR = 0.66, 95%CI 0.48-0.91), recessive (p = 0.002, OR = 1.79, 95%CI 1.25-2.58), overdominant (p = 0.04, OR = 1.35, 95%CI 1.01-1.80) and allele (p = 0.01, OR = 0.72, 95%CI 0.56-0.93) comparisons. But we did not observe any significant associations with hypertensive disorder of pregnancy for other VEGF polymorphisms in overall analyses. Further subgroup analyses by ethnicity showed that rs2010963 polymorphism was significantly associated with hypertensive disorder of pregnancy in Caucasians (dominant and recessive models) and Africans (allele model), whereas rs3025039 polymorphism was significantly associated with hypertensive disorder of pregnancy in Asians (recessive model).

CONCLUSIONS

In summary, our findings indicated that rs2010963 and rs3025039 polymorphisms were both significantly associated with the susceptibility to hypertensive disorder of pregnancy in certain populations.

Effects of GST variants on the risk odds of hematological malignancy: A meta-analysis

BACKGROUND

Whether glutathione S-transferases (GST) polymorphisms influence the risk odds of hematological malignancy remains controversial. Therefore, we performed this meta-analysis to better analyze correlations between GST polymorphisms and hematological malignancy.

METHODS

Literature retrieve was conducted in PubMed, MEDLINE, and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

Sixty-two studies were enrolled for analyses. Significant associations with hematological malignancy were observed for GSTM1 (P < 0.0001, OR = 1.25, 95% CI, 1.14-1.38), GSTP1 (P = 0.002, OR = 1.20, 95% CI, 1.07-1.34), and GSTT1 (P < 0.0001, OR = 1.57, 95% CI, 1.39-1.76) polymorphisms in overall analyses. Further subgroup analyses by ethnicity revealed that GSTM1 and GSTT1 polymorphisms were both significantly correlated with hematological malignancy in Caucasians, East Asians, and West Asians, whereas GSTP1 polymorphism was only significantly correlated with hematological malignancy in Caucasians and West Asians. When we stratified data according to type of disease, positive results were found for all investigated polymorphisms in patients with certain types of acute leukemia. Moreover, GSTP1 polymorphism was also found to be significantly associated with chronic leukemia and lymphoma.

CONCLUSIONS

Our findings indicated that GSTM1, GSTT1, and GSTP1 polymorphisms may serve as potential genetic biomarkers of hematological malignancy in certain ethnicities.

Associations between vitamin D receptor genetic variants and tuberculosis: a meta-analysis

We performed a meta-analysis to evaluate potential associations between vitamin D receptor (VDR) genetic variants and tuberculosis (TB). Systematic literature research was conducted in PubMed, Web of Science, and Embase. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) to estimate strength of associations in all possible genetic models, and P values ≤ 0.05 were considered to be statistically significant. In total, 42 studies were enrolled for analyses. Pooled overall analyses suggested that VDR rs1544410 (dominant model: P = 0.02; allele model: P = 0.03) and rs731236 (dominant model: P = 0.04; recessive model: P = 0.02; allele model: P = 0.01) variants were significantly associated with TB. Further subgroup analyses by ethnicity revealed that rs1544410 (dominant and allele models) and rs731236 (dominant, recessive, and allele models) variants were both significantly associated with TB in South Asians. When we stratified data by type of disease, positive results were detected for rs7975232 variant in EPTB (dominant, recessive, over-dominant, and allele models) subgroup, and for rs2228570 variant in PTB (dominant, recessive, and allele models) and EPTB (dominant, recessive, over-dominant, and allele models) subgroups. Our meta-analysis supported that rs7975232, rs1544410, rs2228570, and rs731236 variants might serve as genetic biomarkers of certain types of TB.

Associations between FCGR polymorphisms and immune thrombocytopenia: A meta-analysis

Several studies already explored associations between Fc gamma receptor (FCGR) polymorphisms and immune thrombocytopenia (ITP), but the results of these studies were not consistent. Consequently, we conducted a meta-analysis of relevant studies to better analyse the effects of FCGR polymorphisms on individual susceptibility to ITP. PubMed, Web of Science, Embase and CNKI were searched for eligible studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Totally 17 studies were eligible for analyses (1200 cases and 1723 controls). Significant associations with ITP were observed for FCGR3A F158V polymorphism in dominant (P < 0.0001, OR = 0.47, 95% CI 0.39-0.57), recessive (P < 0.0001, OR = 2.03, 95% CI 1.58-2.61), overdominant (P < 0.0001, OR = 1.42, 95% CI 1.19-1.69) and allele (P < 0.0001, OR = 0.58, 95% CI 0.51-0.65) models in overall analyses. But we did not observe any significant associations with ITP for FCGR2A H131R and FCGR2B I232T polymorphisms in overall analyses. Subgroup analyses by ethnicity yielded similar positive results for FCGR3A F158V polymorphism in both Asians and Caucasians. Furthermore, subgroup analyses by type of disease revealed that FCGR2A H131R polymorphism was significantly associated with childhood-onset ITP, and FCGR3A F158V polymorphism was significantly associated with both childhood-onset and adult-onset ITP. In summary, our findings suggested that FCGR2A H131R polymorphism may serve as a potential genetic biomarker of childhood-onset ITP, while FCGR3A F158V polymorphism may serve as a potential genetic biomarker of both childhood-onset and adult-onset ITP.

Associations between ADIPOQ polymorphisms and coronary artery disease: a meta-analysis

Background

Whether adiponectin (ADIPOQ) polymorphisms are associated with coronary artery disease (CAD) remain controversial. Therefore, we performed this meta-analysis to better explore potential roles of ADIPOQ polymorphisms in CAD.

Methods

PubMed, Web of Science, Embase and CNKI were searched for eligible studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

Totally 45 studies were included for pooled analyses. A significant association with the susceptibility to CAD was detected for rs2241766 (dominant model: p = 0.0009, OR = 0.82, 95%CI 0.73–0.92; recessive model: p = 0.04, OR = 1.29, 95%CI 1.02–1.64; allele model: p < 0.0001, OR = 0.80, 95%CI 0.73–0.88) polymorphism in overall population. Further subgroup analyses by ethnicity showed that rs1501299 polymorphism was significantly associated with the susceptibility to CAD in East Asians, whereas rs2241766 polymorphism was significantly associated with the susceptibility to CAD in Caucasians, East Asians and South Asians.

Conclusions

Our findings indicated that rs1501299 and rs2241766 polymorphisms both affect the susceptibility to CAD in certain populations.

Correlation between PNPLA3 rs738409 polymorphism and hepatocellular carcinoma: a meta-analysis of 10,330 subjects

PURPOSE

The correlation between patatin-like phospholipase domain-containing protein 3 (PNPLA3) rs738409 polymorphism and hepatocellular carcinoma was investigated by several pilot studies, but the results of these studies were controversial. Therefore, we performed this study to better assess the relationship between PNPLA3 rs738409 polymorphism and the likelihood of hepatocellular carcinoma.

METHODS

Eligible studies were searched in PubMed, Medline, EMBASE, and Web of Science. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the relationship between PNPLA3 rs738409 polymorphism and hepatocellular carcinoma.

RESULTS

A total of 17 studies with 10,330 participants were analyzed. A significant association with the likelihood of hepatocellular carcinoma was detected for the PNPLA3 rs738409 polymorphism in dominant (P = 0.0001; OR 0.66; 95% CI 0.53, 0.82), recessive (P < 0.0001; OR 2.32; 95% CI 1.76, 3.06) and allele (P < 0.0001; OR 0.64; 95% CI 0.53, 0.77) comparisons. Further subgroup analyses revealed that the PNPLA3 rs738409 polymorphism was significantly associated with the likelihood of hepatocellular carcinoma in Caucasians (dominant model: P < 0.0001, OR 0.57, 95% CI 0.45, 0.71; recessive model: P < 0.0001, OR 2.74, 95% CI 2.02, 3.71; allele model: P < 0.0001, OR 0.56, 95% CI 0.46, 0.67). However, no positive results were detected in Asians.

CONCLUSIONS

Our findings indicated that the PNPLA3 rs738409 polymorphism may serve as a potential biological marker of hepatocellular carcinoma in Caucasians.

Correlation between MTHFR polymorphisms and glaucoma: A meta-analysis

Background

Whether methylenetetrahydrofolate reductase (MTHFR) polymorphisms are implicated in glaucoma remains controversial. Therefore, we performed this study to better assess the relationship between MTHFR polymorphisms and the likelihood of glaucoma.

Methods

A systematic research of PubMed, Medline, and Embase was performed to retrieve relevant articles. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

A total of 18 studies with 7,168 participants were analyzed. In overall analyses, a significant association with the likelihood of glaucoma was detected for the rs1801133 polymorphism in dominant (p = 0.04, OR = 0.90, 95%CI 0.81–1.00) and allele (p = 0.02, OR = 0.91, 95%CI 0.84–0.98) comparisons. Further, subgroup analyses by ethnicity revealed that both rs1801131 and rs1801133 polymorphisms were significantly associated with the likelihood of glaucoma in West Asians. However, no positive results were detected for two investigated polymorphisms in East Asians and Caucasians.

Conclusion

Our findings indicated that rs1801131 and rs1801133 polymorphisms may serve as genetic biomarkers of glaucoma in West Asians.

Effects of eNOS gene polymorphisms on individual susceptibility to cancer: A meta-analysis

BACKGROUND

Whether endothelial nitric oxide synthase (eNOS) polymorphisms are implicated in cancer development remains controversial. Therefore, we performed this study to obtain a more conclusive result on associations between eNOS polymorphisms and cancer.

METHODS

Literature retrieve was conducted in PubMed, Medline and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

Forty-one studies were enrolled for analyses. Pooled overall analyses showed that rs1799983 (dominant model: p = 0.01; recessive model: p = 0.007; allele model: p = 0.005), rs2070744 (recessive model: p = 0.004) and rs869109213 (recessive model: p < 0.0001; allele model: p = 0.02) polymorphisms were all significantly associated with individual susceptibility to cancer. Further subgroup analyses revealed that rs2070744 and rs869109213 polymorphisms were only significantly associated with individual susceptibility to cancer in Caucasians, whereas the rs1799983 polymorphism was significantly associated with individual susceptibility to cancer in both Caucasians and Asians.

CONCLUSIONS

Our findings indicated that rs1799983, rs2070744 and rs869109213 polymorphisms may serve as genetic biomarkers of cancer in certain ethnicities.

Effects of MTNR1B genetic variants on the risk of type 2 diabetes mellitus: A meta-analysis

Background

Whether melatonin receptor 1B (MTNR1B) variants are associated with type 2 diabetes mellitus (T2DM) remains unclear. Therefore, we performed this meta‐analysis to better explore correlations between MTNR1B variants and T2DM.

Methods

Literature research was performed in PubMed, Medline, and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

Totally 21 studies were enrolled to analyses. Pooled overall analyses showed that MTNR1B rs10830963 variant was significantly correlated with the susceptibility to T2DM (allele model: p = 0.02, OR = 0.97, 95% CI 0.95–1.00). Further subgroup analyses by ethnicity of participants revealed that rs10830963 variant was significantly correlated with the susceptibility to T2DM in South Asians, but not in Caucasians or East Asians. No any other positive results were found in overall and subgroup analyses.

Conclusions

Our findings indicated that MTNR1B rs10830963 variant might serve as a genetic biomarker of T2DM, especially in South Asians.

A meta-analysis on associations between vitamin D receptor genetic variants and tuberculosis

OBJECTIVES

We aimed to analyze potential associations between vitamin D receptor (VDR) genetic variants and tuberculosis (TB) through a meta-analysis.

METHODS

Systematic literature research of PubMed, Web of Science, Embase and CNKI was performed to identify eligible articles. Statistical analyses were conducted by using Review Manager.

RESULTS

Totally 54 studies were enrolled for analyses. Pooled overall analyses suggested that VDR rs1544410 (dominant model: p = 0.02; allele model: p = 0.04), rs2228570 (recessive model: p = 0.01; allele model: p = 0.03) and rs731236 (recessive model: p = 0.02; allele model: p = 0.02) variants were significantly associated with TB. Further subgroup analyses by ethnicity revealed that rs1544410 variant was significantly associated with TB in South Asians (dominant and allele models) and Caucasians (dominant, recessive and allele models), rs2228570 variant was significantly associated with TB in East Asians (recessive model), and rs731236 variant was significantly associated with TB in South Asians (dominant, recessive and allele models).

CONCLUSIONS

Our meta-analysis suggested that VDR rs1544410, rs2228570 and rs731236 variants might serve as genetic biomarkers of TB in certain populations.

Correlation between PLCE1 rs2274223 variant and digestive tract cancer: A meta-analysis

Background

The relationship between phospholipase C ε‐1 (PLCE1) rs2274223 variant and digestive tract cancer remains inconclusive despite extensive investigations. Therefore, we performed this meta‐analysis to obtain a more credible conclusion.

Methods

PubMed, Medline, and Embase were systematic searched. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

A total of 27 studies were finally included. Pooled analyses suggested that PLCE1 rs2274223 variant was significantly correlated with the likelihood of esophageal cancer (dominant model: p < 0.001, OR = 0.77, 95% CI 0.72–0.83; recessive model: p < 0.001, OR = 1.28, 95% CI 1.12–1.45; additive model: p < 0.001, OR = 1.20, 95% CI 1.11–1.29; allele model: p < 0.001, OR = 0.80, 95% CI 0.74–0.88) and gastric cancer (recessive model: p = 0.001, OR = 1.27, 95% CI 1.10–1.47; allele model: p = 0.03, OR = 0.88, 95% CI 0.78–0.98) in overall population. Further subgroup analyses showed that the positive results were mainly driven by the East Asians. However, no positive results were detected in Caucasians and West Asians.

Conclusion

Our findings indicated that the PLCE1 rs2274223 variant might serve as a promising genetic biomarker of esophageal and gastric cancer in East Asians.

The 6q25.1 rs2046210 polymorphism is associated with an elevated susceptibility to breast cancer: A meta-analysis of 261,703 subjects

BACKGROUND

Several genome-wide association studies already explored the associations between 6q25.1 rs2046210 polymorphism and breast cancer (BC), but the results of these studies were not consistent. Thus, we conducted a meta-analysis of relevant studies to better analyze the effects of rs2046210 polymorphism on individual susceptibility to BC.

METHODS

PubMed, Web of Science, and Embase were searched for eligible studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

Totally 21 studies with 261,703 subjects were analyzed. A significant association with BC was observed for the rs2046210 polymorphism in GG versus GA +AA (dominant comparison, p < 0.0001, OR = 0.78, 95% CI 0.73-0.83), AA versus GG + GA (recessive comparison, p < 0.0001, OR = 1.21, 95% CI 1.18-1.24), GA versus GG + AA (overdominant comparison, p < 0.0001, OR = 1.12, 95% CI 1.08-1.16), and G versus A (allele comparison, p < 0.0001, OR = 0.86, 95% CI 0.82-0.89). Further subgroup analyses yielded similar positive results in both Asians and Caucasians.

CONCLUSION

In summary, our findings suggested that the rs2046210 polymorphism may serve as a potential genetic biomarker of BC in both Asians and Caucasians.

Effects of GST null genotypes on individual susceptibility to leukemia: A meta-analysis

BACKGROUND

Whether glutathione S-transferases (GST) null genotypes influence individual susceptibility to leukemia remains controversial. Thus, we performed this meta-analysis to better analyze potential influences of GST null genotypes on individual susceptibility to leukemia.

METHODS

Literature retrieve was conducted in PubMed, Web of Science and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

Totally fifty-one studies were enrolled for analyses. Significant associations with elevated individual susceptibility to leukemia were detected for GSTM1 (p < .0001, OR = 1.28, 95%CI 1.16-1.41), GSTP1 (p = .003, OR = 1.22, 95%CI 1.07-1.40) and GSTT1 (p < .0001, OR = 1.53, 95%CI 1.35-1.74) null genotypes in overall analyses. Further subgroup analyses by type of disease revealed that GSTM1, GSTP1 and GSTT1 null genotypes were all significantly associated with elevated individual susceptibility to acute lymphoblastic leukemia, GSTM1 and GSTT1 null genotypes were significantly associated with elevated individual susceptibility to acute myeloid leukemia, and GSTT1 null genotype was also significantly associated with elevated individual susceptibility to chronic leukemia. When we stratified data according to ethnicity of participants, positive results were found for all investigated variants in Caucasians and West Asians. Additionally, GSTM1 null genotype was also significantly correlated with elevated individual susceptibility to leukemia in East Asians.

CONCLUSIONS

Our findings indicated that GSTM1, GSTT1 and GSTP1 null genotypes might serve as potential genetic biomarkers of leukemia in certain ethnicities.

A meta-analysis on correlations of OX40L variants with atherosclerotic disorders

BACKGROUND

This meta-analysis was conducted to analyze the correlations of OX40 ligand (OX40L) variants with atherosclerotic cardio-cerebral vascular diseases (ASCVD).

METHODS

Systematic literature research was conducted in PubMed, Medline, and Embase. All statistical analyses were conducted with Review Manager.

RESULTS

Totally eighteen studies were enrolled for analyses. Although no any significant correlations between OX40L variants and ASCVD were detected in overall analyses. Further subgroup analyses by ethnicity revealed that rs1234314 variant was significantly associated with ASCVD in East Asians (dominant model: P = 0.03, odds ratios [OR] = 1.15, 95% confidence interval [CI], 1.01-1.31; allele model: P = 0.04, OR = 1.10, 95%CI, 1.00-1.20). When we stratified eligible studies by type of disease, positive results were observed for rs17568 variant in subjects with acute coronary syndrome (ACS) (allele model: P = 0.04, OR = 0.81, 95%CI, 0.65-0.99), for rs1234314 variant in subjects with coronary artery disease (CAD) (dominant model: P = 0.04, OR = 1.16, 95%CI, 1.00-1.35), for rs3850641 variant in subjects with CAD (recessive model: P = 0.02, OR = 1.42, 95%CI, 1.05-1.90) and myocardial infarction (MI) (recessive model: P = 0.03, OR = 1.49, 95%CI, 1.05-2.11).

CONCLUSIONS

Our findings suggested that rs17568, rs1234314, and rs3850641 variants might serve as genetic biomarkers of certain types of CAD.

Genetic associations between Transcription Factor 7 Like 2 rs7903146 polymorphism and type 2 diabetes mellitus: a meta-analysis of 115,809 subjects

BACKGROUND

Some genetic association studies tried to investigate potential associations of Transcription Factor 7 Like 2 (TCF7L2) rs7903146 polymorphism with type 2 diabetes mellitus (T2DM). However, the results of these studies were not consistent. Thus, we performed the present meta-analysis to explore associations between TCF7L2 rs7903146 polymorphism and T2DM in a larger pooled population.

METHODS

Systematic literature research of PubMed, Web of Science and Embase was performed to identify eligible studies for pooled analyses. I² statistics were employed to assess between-study heterogeneities. If I² was greater than 50%, random-effect models (REMs) would be used to pool the data. Otherwise, fixed-effect models (FEMs) would be applied for synthetic analyses.

RESULTS

Totally 68 studies with 115,809 subjects were included for analyses. The pooled analyses showed that TCF7L2 rs7903146 (dominant model: p < 0.0001; recessive model: p < 0.0001; over-dominant model: p < 0.0001; allele model: p < 0.0001) polymorphism was significantly associated with susceptibility to T2DM in overall population. Further subgroup analyses revealed similar significant findings in both Asians and Caucasians.

CONCLUSIONS

In conclusion, our findings supported that TCF7L2 rs7903146 polymorphism could be used to identify individuals at high risk of developing T2DM in Asians and Caucasians.

WITHDRAWN: A meta-analysis on associations of CDKN2B-AS variants with atherosclerotic cardio-cerebral vascular diseases

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Association between α-adducin rs4961 polymorphism and hypertension: A meta-analysis based on 40 432 subjects

BACKGROUND

Recently, the role of α-adducin rs4961 polymorphism in hypertension (HTN) was intensively analyzed, but the results of these studies were inconsistent. Therefore, we performed this study to better assess the relationship between α-adducin rs4961 polymorphism and the likelihood of HTN.

METHODS

Eligible studies were searched in PubMed, Medline, Embase, and Web of Science. Odds ratios with 95% confidence intervals were used to assess the relationship between α-adducin rs4961 polymorphism and HTN.

RESULTS

A total of 33 studies with 40 432 participants were analyzed. Significant associations with the likelihood of HTN were detected for the α-adducin rs4961 polymorphism with fixed effect models (FEM) (dominant model: P = 0.003; allele model: P = 0.003), but not with random effect models (REM). Further subgroup analysis according to ethnicity of participants revealed that the α-adducin rs4961 polymorphism was significantly associated with the likelihood of HTN in Asians (7721 cases and 8299 controls) with both FEMs (dominant model: P < 0.0001; additive model: P = 0.01; allele model: P < 0.0001) and REMs (dominant model: P = 0.0005; additive model: P = 0.03; allele model: P = 0.0006).

CONCLUSIONS

Our findings indicate that the α-adducin rs4961 polymorphism may serve as a genetic biomarker of HTN in Asians.

Effects of ADIPOQ polymorphisms on PCOS risk: a meta-analysis

BACKGROUND

Whether adiponectin (ADIPOQ) polymorphisms are associated with the risk of polycystic ovary syndrome (PCOS) remain controversial. Therefore, we performed this study to better explore correlations between ADIPOQ polymorphisms and PCOS risk.

METHODS

Literature retrieve was conducted in PubMed, Medline and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

Eighteen studies were enrolled for analyses. Pooled overall analyses showed that rs1501299 polymorphism was significantly associated with PCOS risk (recessive model: p = 0.02, OR = 0.77, 95%CI 0.62-0.95; allele model: p = 0.001, OR = 1.15, 95%CI 1.06-1.26). Further subgroup analyses according to ethnicity of participants revealed that rs1501299 and rs2241766 polymorphisms were both significantly correlated with PCOS risk in Caucasians. In addition, rs1501299 polymorphism was also significantly correlated with PCOS risk in East Asians.

CONCLUSIONS

Our findings indicated that rs1501299 and rs2241766 polymorphisms might serve as genetic biomarkers of PCOS in certain ethnicities.

Associations of β-Fibrinogen Polymorphisms with the Risk of Ischemic Stroke: A Meta-analysis

BACKGROUND

Recently, the roles of β-fibrinogen (FGβ) polymorphisms in ischemic stroke (IS) were intensively analyzed, but the results of these studies were inconsistent. Thus, we performed this study to better assess potential relationship between FGβ polymorphisms and the risk of IS.

METHODS

Eligible studies were searched in PubMed, Medline, Embase, and CNKI. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate correlations between FGβ polymorphisms and IS.

RESULTS

A total of 49 studies were included for analyses. Significant associations with the risk of IS were detected for FGβ -148 C/T and -455 G/A polymorphisms in overall analyses. Further subgroup analyses according to ethnicities of participants revealed that the -148 C/T polymorphism was significantly correlated with the risk of IS in both Asians and Caucasians, while the -455 G/A polymorphism was only significantly correlated with the risk of IS in Asians. When we stratified available data according to types of disease, we found that both FGβ -148 C/T and -455 G/A polymorphisms were significantly correlated with the risk of cerebral infarction.

CONCLUSIONS

Our findings indicated that FGβ -148 C/T and -455 G/A polymorphisms may serve as potential biological markers for IS in Asians. Moreover, the FGβ -148 C/T polymorphism may also serve as a potential biological marker for IS in Caucasians.

A comprehensive meta-analysis on relationship between CYP11B2 rs1799998 polymorphism and atrial fibrillation

BACKGROUND

The correlation between CYP11B2 rs1799998 polymorphism and atrial fibrillation (AF) was analyzed by several studies, but the results of these studies were inconsistent. Thus, we performed this study to obtain a more conclusive result on relationship between CYP11B2 rs1799998 polymorphism and AF.

METHODS

Eligible studies were searched in PubMed, Medline and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the strength of correlation.

RESULTS

A total of 12 studies with 5466 participants were analyzed. We found that CYP11B2 rs1799998 polymorphism was significantly associated with AF in overall population under recessive genetic model with FEM (P = 0.005, OR = 1.29, 95%CI 1.08-1.54), but no positive results were detected in overall analyses with REMs. Further subgroup analyses revealed that CYP11B2 rs1799998 polymorphism was significantly correlated with AF in East Asians, but not in West Asians. Furthermore, significant associations between rs1799998 polymorphism and AF were observed in subjects with essential hypertension (EH) and heart failure (HF). No any other positive results were found in overall and subgroup analyses.

CONCLUSIONS

Overall, our meta-analysis suggested that rs1799998 polymorphism may serve as a potential biological marker of AF in East Asians and subjects with EH or HF.

Effects of ANRIL polymorphisms on the likelihood of coronary artery disease: A meta-analysis

BACKGROUND

Whether antisense noncoding RNA in the INK4 locus (ANRIL) polymorphisms are associated with the likelihood of coronary artery disease (CAD) remains controversial. Therefore, we performed this study to explore correlation between ANRIL polymorphisms and CAD.

METHODS

Literature retrieve was conducted in PubMed, Medline and Embase. Odds ratios and 95% confidence intervals were calculated.

RESULTS

Nineteen studies were enrolled for analyses. Pooled overall analyses showed that rs1333040 (dominant model: P < 0.0001; recessive model: P < 0.0001; allele model: P < 0.0001), rs1333049 (dominant model: P = 0.02; allele model: P = 0.02) and rs2383207 (additive model: P = 0.004; allele model: P = 0.03) polymorphisms were significantly associated with the likelihood of CAD. Further subgroup analyses revealed that rs1333040, rs1333049, rs2383206, rs2383207, rs10757274, and rs10757278 polymorphisms were all significantly correlated with the likelihood of CAD in East Asians. Additionally, rs2383206, rs10757274, and rs10757278 polymorphisms were also significantly correlated with the likelihood of CAD in Caucasians and West Asians.

CONCLUSIONS

Our findings indicated that rs1333040, rs1333049, rs2383206, rs2383207, rs10757274, and rs10757278 polymorphisms may serve as genetic biomarkers of CAD in East Asians. Moreover, rs2383206, rs10757274, and rs10757278 polymorphisms may also serve as genetic biomarkers of CAD in Caucasians and West Asians.

Potential genetic polymorphisms predicting polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a heterogenous endocrine disorder with typical symptoms of oligomenorrhoea, hyperandrogenism, hirsutism, obesity, insulin resistance and increased risk of type 2 diabetes mellitus. Extensive evidence indicates that PCOS is a genetic disease and numerous biochemical pathways have been linked with its pathogenesis. A number of genes from these pathways have been investigated, which include those involved with steroid hormone biosynthesis and metabolism, action of gonadotropin and gonadal hormones, folliculogenesis, obesity and energy regulation, insulin secretion and action and many others. In this review, we summarize the historical and recent findings in genetic polymorphisms of PCOS from the relevant publications and outline some genetic polymorphisms that are potentially associated with the risk of PCOS. This information could uncover candidate genes associating with PCOS, which will be valuable for the development of novel diagnostic and treatment platforms for PCOS patients.