PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “mendelian randomization study”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

To unveil the causal relationship between immunophenotypes and colorectal cancer using two-sample bidirectional Mendelian randomization and mediation analyses.

Colorectal cancer (CRC) is a leading cause of cancer-related death worldwide. The mechanisms underlying this trend are not yet fully understood. This study aimed to examine the potential role of genetically predicted immunophenotypes in the development of CRC. A two-sample bidirectional Mendelian randomization study was conducted to explore the relationship between 731 genetically predicted immune cells and CRC. Furthermore, a two-step Mendelian randomization approach was employed to assess the possible mediating effect of immune cells on CRC. The inverse-variance weighted method identified 5 immunophenotypes as significantly inversely associated with CRC risk: the odds ratios for CRC risk associated with activated CD4 regulatory T cells (%CD4 regulatory T cells), CD25++ CD45RA- CD4 nonregulatory T cells (%CD4 + T cells), CD25++ CD45RA- CD4 nonregulatory T cells (%T cells), CD25++ CD8 + T cells (%T cells), and CD64 + CD16 + monocytes were 0.925 (95% CI = 0.874-0.978, P = 6.516 × 10-3), 0.935 (95% CI = 0.878-0.995, P = .035), 0.936 (95% CI = 0.889-0.985, P = .011), 0.863 (95% CI = 0.786-0.948, P = 2.142 × 10-3), and 0.636 (95% CI = 0.519-0.778, P = 1.18 × 10-5), respectively. The mediation analysis indicated that the absolute count of CD25++ CD8 + T cells led to a 33.9% decrease in the risk associated with the percentage of activated CD4 regulatory T cells within CD4 regulatory T cells and CRC. Our analysis revealed that 5 immunophenotypes may be risk factors for CRC. Since other complementary methods have yielded inconsistent results, however, further investigation is necessary.

Colorectal Neoplasms↗

Alcohol, ALDH2, and esophageal cancer: a meta-analysis which illustrates the potentials and limitations of a Mendelian randomization approach.

Mendelian randomization, the use of common polymorphisms as surrogates for measuring exposure levels in epidemiologic studies, provides one method of assessing the causal nature of some environmental exposures. This can be illustrated by looking at the association between the ALDH2 polymorphism and esophageal cancer. Alcohol drinking is considered a risk factor for esophageal cancer, and exposure to high levels of acetaldehyde, the principal metabolite of alcohol, may be responsible for the increased cancer risk. The ability to metabolize acetaldehyde is encoded by the ALDH2 gene, which is polymorphic in some populations. The ALDH2*2 allele produces an inactive protein subunit, which is unable to metabolize acetaldehyde. An individual's genotype at this locus may influence their esophageal cancer risk through two mechanisms, first through influencing alcohol intake and second through influencing acetaldehyde levels. We have carried out a meta-analysis of studies looking at the ALDH2 genotype and esophageal cancer and found that risk was reduced among *2*2 homozygotes [odds ratio (OR), 0.36; 95% confidence interval (95% CI), 0.16-0.80] and increased among heterozygotes (OR, 3.19; 95% CI, 1.86-5.47) relative to *1*1 homozygotes. This provides strong evidence that alcohol intake increases the risk of esophageal cancer and individuals whose genotype results in markedly lower intake, because they have an adverse reaction to alcohol are thus protected. This meta-analysis also provides evidence that acetaldehyde plays a carcinogenic role in esophageal cancer. The two different processes operating as a result of the ALDH2 genotype have implications for the interpretation of studies using the Mendelian randomization paradigm.

Acetaldehyde↗

Association of genetically proxied cancer-targeted drugs with cardiovascular diseases through Mendelian randomization analysis.

BACKGROUND: Cancer-targeted therapies are progressively pivotal in oncological care. Observational studies underscore the emergence of cancer therapy-related cardiovascular toxicity (CTR-CVT), impacting patient outcomes. We aimed to investigate the causal relationship between different types of cancer-targeted therapies and cardiovascular disease (CVD) outcomes through a two-sample Mendelian randomization (MR) study. METHODS: This genome-wide association study was conducted using a two-sample Mendelian randomization framework. Genetic instruments for drug target gene expression were extracted from the eQTLGen consortium (31684 individuals, 37 cohorts). Genome-wide association study (GWAS) summary statistics for 19 cardiovascular diseases were derived from the FinnGen database. Primary analysis was carried out using the summary-data-based MR (SMR) method, with sensitivity analysis for validation. Colocalization analysis identifies shared causal variants between exposure eQTLs and CVD-associated single-nucleotide polymorphisms (SNPs). RESULTS: Among the 39 drug target genes, 8 were identified with detectable cis-eQTLs and were subsequently validated through positive control analysis for further investigation. In the SMR and sensitivity analyses, genetically proxied VEGFA inhibition showed significantly strong association with stroke (odds ratio [OR] = 1.17, 95% confidence interval [CI] = 1.09-1.26, p = 1.33 × 10- 5). Additionally, the inhibition of FGFR1, FLT1, and MAP2K2 exhibited suggestive association with corresponding cardiovascular disease outcomes. Nevertheless, only VEGFA expression and stroke shared a causal variant (93.6%), whereas FGFR1, MAP2K2, and FLT1 did not share causal variants with corresponding cardiovascular diseases in the colocalization analysis. CONCLUSIONS: This genetic association study revealed evidence supporting the genetic association between the use of VEGFA inhibitors and increased stroke risk, highlighting the need for enhanced pharmacovigilance. These findings underscore the delicate balance between cardiovascular toxicity risk and the benefits of cancer-targeted therapy.

Humans↗

Association of cancers with the occurrence and 28-day mortality of sepsis: a mendelian randomization and mediator analysis.

Observational studies have indicated an association between cancer and the occurrence of sepsis, with an increased risk of mortality in cancer-related sepsis. However, whether a causal relationship exists between the two remains unknown. Summary statistics of thirteen cancers from the largest available genome-wide association studies (GWAS) of GWAS catalog and FinnGen biobank were extracted for the MR analysis. GWAS data for sepsis and its 28-day mortality were obtained from MRC-IEU. Univariable, multivariable, and reverse MR analyses were employed to explore potential associations between cancers and sepsis and its 28-day mortality. Moreover, a two-step mediation MR analysis was performed to investigate independent positive causal relationships between cancers and sepsis and its 28-day mortality. In univariable Mendelian randomization (MR) analysis, significant causal relationships were found between genetically predicted lung cancer (OR = 1.17, 95% CI = 1.08-1.26, adjusted p = 0.001), squamous cell lung carcinoma (OR = 1.10, 95% CI = 1.02-1.18, adjusted p = 0.042), lung adenocarcinoma (OR = 1.12, 95% CI = 1.03-1.21, adjusted p = 0.032), small cell lung carcinoma (OR = 1.07, 95% CI = 1.02-1.12, adjusted p = 0.031), and sepsis. Subsequent multivariable MR analysis revealed that these three types of lung cancer were independently associated with the risk of sepsis. Additionally, a causal relationship was found between lung cancer and 28-day mortality from sepsis, while no causal link was observed between non-solid tumors and the onset or death of sepsis. Reverse MR analysis did not indicate a potential for sepsis to trigger the onset of cancers. Furthermore, TRAIL was found to have promotive effects on the occurrence and mortality of sepsis. Lung cancer causally correlates with increased sepsis occurrence and 28-day mortality, as evidenced by Mendelian Randomization analysis. Genetic predispositions enhance this risk, underscoring the potential of genetic profiling to guide early, precise sepsis interventions in these patients.

Humans↗

Mendelian randomization and FinnGen analysis of the causal relationship between 473 gut microbiota species and chronic sinusitis.

OBJECTIVE: To investigate the causal associations between Gut Microbiota (GM) and Chronic Sinusitis (CRS) using Mendelian Randomization (MR). METHODS: Genome-Wide Association Study (GWAS) summary statistics for 473&#x2009;GM taxa were obtained from MiBioGen consortium. CRS data (22,099 cases vs. 371,520 controls) were sourced from the FinnGen R12 cohort. Causal effects were estimated via Inverse Variance-Weighted (IVW), MR-Egger, weighted median, and Bayesian-weighted MR methods. Sensitivity analyses (heterogeneity and horizontal pleiotropy tests) were performed to validate robustness. RESULTS: IVW analysis identified 20&#x2009;GM taxa significantly associated with CRS risk (p&#x2009;<&#x2009;0.05). Of these, 7 taxa (e.g., Francisellales, Roseibacillus, Merdibacter massiliensis) exhibited risk-increasing effects, while 13 taxa (e.g., Firmicutes I, Succinivibrionaceae) showed protective effects. Sensitivity analyses confirmed the absence of significant heterogeneity (Cochran's Q p&#x2009;>&#x2009;0.05) or pleiotropy (MR-Egger intercept p&#x2009;>&#x2009;0.05). Bayesian-weighted MR validated 18 causal relationships (posterior probability > 95%), except for RUG420 sp900317985 and UBA7703 (non-significant). CONCLUSIONS: This MR study provides genetic evidence supporting causal roles of specific GM taxa in CRS pathogenesis. These findings highlight the gut-sinus axis as a potential therapeutic target and underscore the utility of large-scale biobanks (e.g., FinnGen) in advancing precision medicine. LEVEL OF EVIDENCE: Level 5. Mendelian Randomized (MR) studies are second only to randomized controlled trials in terms of the level of evidence.

Humans↗

Patient stratification by genetic risk in Alzheimer's disease is only effective in the presence of phenotypic heterogeneity.

Case-only designs in longitudinal cohorts are a valuable resource for identifying disease-relevant genes, pathways, and novel targets influencing disease progression. This is particularly relevant in Alzheimer's disease (AD), where longitudinal cohorts measure disease "progression," defined by rate of cognitive decline. Few of the identified drug targets for AD have been clinically tractable, and phenotypic heterogeneity is an obstacle to both clinical research and basic science. In four cohorts (n = 7241), we performed genome-wide association studies (GWAS) and Mendelian randomization (MR) to discover novel targets associated with progression and assess causal relationships. We tested opportunities for patient stratification by deriving polygenic risk scores (PRS) for AD risk and severity and tested the value of these scores in predicting progression. Genome-wide association studies identified no loci associated with progression at genome-wide significance (&#x3b1; = 5&#xd7;10-8); MR analyses provided no significant evidence of an association between cognitive decline in AD patients and protein levels in brain, cerebrospinal fluid (CSF), and plasma. Polygenic risk scores for AD risk did not reliably stratify fast from slow progressors; however, a deeper investigation found that APOE &#x3b5;4 status predicts amyloid-&#x3b2; and tau positive versus negative patients (odds ratio for an additional APOE &#x3b5;4 allele = 5.78 [95% confidence interval: 3.76-8.89], P<0.001) when restricting to a subset of patients with available CSF biomarker data. These results provided no evidence for large-effect, common-variant loci involved in the rate of memory decline, suggesting that patient stratification based on common genetic risk factors for progression may have limited utility. Where clinically relevant biomarkers suggest diagnostic heterogeneity, there is evidence that a priori identified genetic risk factors may have value in patient stratification. Mendelian randomization was less tractable due to the lack of large-effect loci, and future analyses with increased samples sizes are needed to replicate and validate our results.

Alzheimer Disease↗

Single-cell expression quantitative trait locus Mendelian randomization reveals immune cell-specific causal regulatory networks and actionable targets in polycystic ovary syndrome.

ObjectiveTo systematically investigate whether the pathogenesis of polycystic ovary syndrome (PCOS) is causally related to dysregulated gene expression in specific immune cell subsets, and to evaluate the potential of these causal genes as actionable drug targets.MethodsThis study employed a two-sample Mendelian randomization (MR) framework using publicly available genome-wide association study (GWAS) summary statistics. The participant data included 797 PCOS cases and 140,558 controls (no direct patient recruitment was involved). Instrumental variables were derived from high-resolution immune cell-specific single-cell expression quantitative trait locus (sc-eQTL) data (OneK1K project) across 14 immune cell types. Primary analyses utilized the inverse-variance weighted (IVW) method. Shared causal variants were validated using Bayesian colocalization. Phenome-wide association analysis (PheWAS), external transcriptomic dataset validation (GSE8157), and DrugBank database screening were conducted for pleiotropy assessment and drug repositioning.ResultsMR analysis revealed genome-wide significant causal associations for GLIPR1 in non-classical monocytes (Mono NC) and XBP1 in CD4+ effector memory T cells (CD4 ET) with PCOS risk. Higher GLIPR1 expression was associated with a decreased PCOS risk (OR = 0.669, P = 4.34&#xd7;10-6), whereas higher XBP1 expression was associated with an increased risk (OR = 1.406, P = 9.53&#xd7;10-8). Colocalization analysis confirmed that GLIPR1 shares a causal variant with PCOS (PP.H4 = 96.73%). PheWAS and external validation confirmed the safety profile and significant upregulation (P = 0.03) of GLIPR1. Drug repositioning identified SOT-107, a Phase III protein therapy drug, as a potential interacting agent for GLIPR1.ConclusionsThis sc-eQTL MR study reveals immune cell-specific causal regulatory networks in PCOS. GLIPR1 in non-classical monocytes represents a high-confidence protective target, while XBP1 provides suggestive evidence for immune-mediated pathogenesis. The candidate drug SOT-107 highlights theoretical repositioning opportunities, though rigorous preclinical validation remains required.

Female↗

Integrative Multi-Omics Analysis Identifies Thrombosis-Associated Molecular Features Linked to Germline Susceptibility and Immune Cell Communication in Gastric Cancer.

Emerging evidence indicates that coagulation-related molecular programs are associated with thrombosis, tumor progression, and molecular dysregulation in gastric cancer (GC). However, thrombosis-associated molecular features in GC and their potential links to inherited susceptibility remain insufficiently understood. Integrated analyses of transcriptomic data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets were performed to identify thrombosis-associated genes and establish a machine learning-based prognostic signature. Genome-wide association study (GWAS), expression quantitative trait loci (eQTL), transcriptome-wide association study (TWAS), and Mendelian randomization (MR) analyses were conducted to investigate susceptibility-associated transcriptional programs in GC. Functional assays were used to evaluate candidate genes associated with malignant phenotypes. Single-cell RNA sequencing (scRNA-seq) and cell-cell communication analyses were further performed to characterize cell-type-specific expression patterns and potential intercellular interactions. A total of 22 differentially expressed thrombosis-associated genes were identified, and a prognostic signature comprising 14 genes was established. The signature stratified patients into high- and low-risk groups and showed prognostic performance in both the training and validation cohorts. Integrative GWAS, eQTL, and TWAS analyses identified susceptibility-associated transcriptional programs that were positively correlated with the thrombosis-associated risk score. Silencing ACTN2 and CRYAB significantly reduced GC cell migration and invasion. scRNA-seq analysis revealed relatively high CRYAB expression in neutrophils, and CellChat analysis suggested potential neutrophil-B cell interactions involving COLLAGEN-related signaling. This integrative multi-omics study identified a thrombosis-associated molecular signature linked to prognosis and germline susceptibility-associated transcriptional programs in GC. ACTN2 and CRYAB may represent candidate genes associated with GC cell migration and invasion, while single-cell analysis suggested potential immune-related communication features.

Humans↗

Genetic evidence for a causal relationship between melatonin metabolism and depression.

To investigate the causal relevance of melatonin metabolism, which provides the biological basis for circulating melatonin levels, to specific depression symptom subtypes, we performed a targeted systematic review of melatonin metabolism pathways in the human brain and liver. Using two-sample Mendelian randomization (MR), we assessed the causal effects of metabolism pathways and/or individual genes on major depressive disorder (MDD) and nine symptom subtypes derived from Patient Health Questionnaire-9 (PHQ-9). Instrumental variables (IVs) were expression quantitative trait loci (eQTL) for eight individual genes, one synthesis route, and three degradation routes. Results were assessed using Bayesian colocalization and phenome-wide association analyses. At the pathway-level, the genetically proxied synthesis-route signal was associated with PHQ-9 Assessment 5 (PHQ9A5, OR: 0.89, 95% CI: 0.85-0.93), but sensitivity analyses suggested this association was primarily driven by TPH1 and may reflect serotonin-related biology. In contrast, higher brain melatonin degradation raised the risk of both PHQ9A1 (OR: 1.03, 95% CI: 1.02-1.04) and PHQ9A7 (OR: 1.03, 95% CI: 1.02-1.03). Within degradation, up-regulation of the kynurenine sub-pathway increased the odds of PHQ9A3 (OR: 1.05, 95% CI: 1.02-1.07), PHQ9A4 (OR&#xa0;=&#xa0;1.04, 95% CI: 1.02-1.06) and PHQ9A7 (OR: 1.05, 95% CI: 1.02-1.07). Gene-level analyses were largely concordant, except for SULT1A1, whose higher expression was genetically protective for PHQ9A3 but risk-increased for PHQ9A1 and PHQ9A4. Overall, these results demonstrate that melatonin metabolism exerts symptom-specific and pathway-specific causal effects on depression. A stratified view of melatonin's role may help optimize the application of exogenous melatonin supplementation.

Melatonin↗

Social isolation and 59 common health conditions: insights from observational and genetics analyses.

BACKGROUND: The impacts of social isolation on diverse health conditions and how it contributes to health risks remain unclear. We aimed to investigate the associations of social isolation with 59 health conditions among older adults. METHODS: Participants from the UK Biobank without baseline diagnosis of the included diseases were selected. Social isolation was assessed with three questions. The 59 health conditions included all-cause mortality, 5 cause-specific mortalities, and 53 diseases. We used an instrumental variable from multivariable common factor GWAS in Mendelian randomization (MR) to explore causal links of social isolation with diseases. Omics analyses were conducted to assess the roles of Olink plasma proteins and metabolomics, and PERM was calculated to evaluate the influence of other factors. RESULTS: A total of 489,741 individuals [266,706 (54.5%) women; mean age 56.5&#xa0;years (SD 8.1)] were included. During a median follow-up of 12.5&#xa0;years, social isolation was uncorrelated with the majority of 59 health conditions. Significantly, it was associated with increased risks of all-cause [adjusted HR (aHR) 1.28, 95% CI 1.25-1.32], 5 cause-specific mortalities (aHR range, 1.18-1.38), and 11 specific diseases (aHR range, 1.08-1.17). Living alone was the strongest item of isolation in predicting mortality (aHR range, 1.18-1.45) and selected diseases. MR analyses offered little evidence to support a causal link between social isolation and these diseases. The proteins involved in these associations are predominantly related to "response to stimulus". Proteomic signatures (PERM, 36%-49%), health behaviours (32%-59%), and socioeconomic factors (22%-42%) were the main explanatory factors linking social isolation to 8 health outcomes. CONCLUSIONS: Social isolation is associated with elevated risks of 17 out of the 59 examined adverse health outcomes, predominantly mortality-related conditions; however, MR analyses indicate an absence of evidence supporting causality for these associations.

Humans↗

Causality between noise pollution and Alzheimer disease: A Mendelian randomization analysis.

The role of noise pollution as a risk factor for Alzheimer disease (AD) is unclear, with observational studies yielding conflicting results susceptible to confounding and reverse causality. To clarify this relationship, we performed a 2-sample Mendelian randomization (MR) study using summary statistics from large-scale genome-wide association studies of European populations. Genetically predicted daytime and evening noise exposure was used as an instrumental variable to assess a causal effect on AD risk. The primary analysis was conducted using the inverse-variance weighted method, with weighted median and MR-Egger methods as key sensitivity analyses. We assessed instrument validity and pleiotropy using the Cochran Q test, the MR-Egger intercept, and leave-one-out analysis. Our MR analysis found no evidence of a causal association between genetically predicted daytime noise (odds ratio [95% confidence interval]&#x2005;=&#x2005;0.999 [0.993-1.006], P&#x2005;=&#x2005;.819) or evening noise (odds ratio [95% confidence interval]&#x2005;=&#x2005;0.999 [0.993-1.005], P&#x2005;=&#x2005;.643) and the risk of AD. Sensitivity analyses were consistent, with no evidence of heterogeneity or directional pleiotropy. In conclusion, this study does not support a direct causal link between noise and AD. While our findings mitigate common observational biases, they do not preclude indirect mechanisms whereby noise may influence AD pathogenesis via established risk pathways, such as chronic sleep disruption and cardiovascular stress. Studies are needed to focus on disentangling these potential indirect effects.

Alzheimer Disease↗

The association between GLP-1R expression and cardiovascular-kidney-metabolic-related diseases in non-diabetic and non-obese population: evidence triangulation using Mendelian randomization, observational and polygenic score association analysis.

BACKGROUND: Glucagon-like peptide-1 receptor (GLP-1R) agonists are emerging as promising therapies for cardiovascular-kidney-metabolic (CKM) related diseases in individuals with type 2 diabetes mellitus (T2DM) or obesity. But their effects in non-obese and non-diabetic individuals are unclear. This study triangulates evidence using Mendelian randomization (MR), polygenic scores (PGS) and observational analyses to estimate the associations of GLP-1R expression with chronic kidney disease (CKD), heart failure (HF) and metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: For the MR analysis, instruments mimicking GLP-1R expression were identified using pancreas-specific cis-expression quantitative trait loci from GTEx (N&#x2009;&#x2264;&#x2009;305). MR-Robust method was used as the primary MR approach. PGS and observational analyses were performed both in non-diabetic and non-obese individuals separately. A genome-wide association study (GWAS) for MASLD (14,231 cases and 348,091 controls) was performed in the general population using data from UK Biobank. RESULTS: GLP-1R expression showed robust effects on CKD (odds ratio [OR] 0.96, 95%CI 0.95 to 0.97, q&#x2009;=&#x2009;1.7&#x2009;&#xd7;&#x2009;10-&#x2009;10 ), HF (OR&#x2009;=&#x2009;0.96, 95%CI 0.94 to 0.97, q&#x2009;=&#x2009;2.5&#x2009;&#xd7;&#x2009;10-&#x2009;8) and MASLD (OR&#x2009;=&#x2009;0.96, 95%CI 0.93 to 0.98, q&#x2009;=&#x2009;1.3&#x2009;&#xd7;&#x2009;10-&#x2009;3) in the general population. Consistent results were observed in validation analyses. Furthermore, PGS and observational analyses among non-T2DM and non-obese individuals found little evidence to support its association with CKD, HF or MASLD. GWAS analysis identified eight conditionally independent variants associated with MASLD, in which rs563199662 was a new signal located at TFPI region. CONCLUSIONS: This study provides multilayered evidence for GLP-1R expression in mitigating CKD, HF and MASLD risks in the general population, while de-prioritized its effect on CKM-related diseases in non-obese and non-diabetic individuals. Further clinical trials are needed to validate the effects of GLP-1R agonists in relative health population.

Humans↗

Multi-omics Mendelian Randomization Prioritizes Neutrophil Extracellular Trap-related Genes Associated with Atrial Fibrillation Risk.

BACKGROUND: Neutrophil extracellular traps (NETs) participate in thrombosis, inflammation, and cardiovascular remodeling, yet whether NET-related genes (NRGs) are associated with atrial fibrillation (AF) risk across multiple molecular layers remains unclear. This study used a multiomics Mendelian randomization framework to prioritize NRGs supported by methylation, expression, and protein quantitative trait loci (QTL) data. METHODS: Genome-wide significant cis instruments (P < 5 &#xd7; 10-8) were obtained for 90 methylation QTLs (mQTLs), 100 expression QTLs (eQTLs), and 38 protein QTLs (pQTLs) mapped to 137 literature- curated NRG entries. Summary-data-based Mendelian randomization (SMR) coupled with the heterogeneity in dependent instruments (HEIDI) test was applied using whole-blood mQTL data (n = 1,980), eQTLGen blood eQTL data (n = 31,684), and deCODE plasma pQTL data (n = 35,559). AF outcome data were obtained from a meta-analysis including 60,620 cases and 970,216 controls of European ancestry. RESULTS: At the methylation level, 21 CpG-feature associations across 13 genes remained significant after HEIDI filtering and false discovery rate (FDR) correction. Expression-level analysis identified eight significant gene-AF associations, whereas protein-level analysis identified seven significant features representing five unique proteins. Cross-omics integration prioritized C3, MAPK3, and STAT3 as Tier 1 genes, CTSC, LPAR3, and THBD as Tier 2 genes, and fourteen additional genes as Tier 3 candidates. C3 showed risk-increasing protein-level associations together with multiple significant CpG signals, whereas MAPK3 and STAT3 showed directionally protective expression/protein or methylation/protein patterns. DISCUSSION: The cross-omics convergence on C3, MAPK3, and STAT3 is consistent with complement activation, immune-fibrotic signaling, and cytokine-regulatory pathways implicated in AF biology, but the findings should be interpreted as genetic prioritization rather than definitive intervention-ready causality. CpG-level heterogeneity at the C3 locus and the blood/plasma origin of the QTL resources further support a cautious interpretation. Modest colocalization support and the unresolved possibility of pQTL sample overlap further support this cautious, hypothesis-generating interpretation. CONCLUSION: Multi-omics SMR prioritizes C3, MAPK3, and STAT3 as the most consistently supported NET-related genes associated with AF risk. These findings provide a framework for atrialtissue replication and mechanistic validation of NET-related pathways in AF.

Atrial fibrillation↗

Mendel randomization confirmed gastroesophageal reflux disease may increase the risk of mental disorders.

BACKGROUND: The potential causal relationship between gastroesophageal reflux disease (GERD) and mental disorder was analyzed using the mendelian randomization (MR) method. METHODS: Data are derived from genome-wide association study (GWAS) summary data, using gastroesophageal reflux disease (GERD) as the exposure factor. Single nucleotide polymorphisms (SNPs) significantly associated with GERD were selected as instrumental variables (IVs), and mental disorders (bipolar disorder, major depression, Alzheimer's disease, anorexia nervosa, anxiety, and obsessive-compulsive disorder) were used as outcome variables. The inverse variance weighted (IVW) method is used as the main analysis method, and MR-Egger regression, weighted median (WM) method, simple mode and weighted mode are used as supplementary methods for Mendelian randomization (MR) analysis. Cochran's Q&#xa0;test and P&#xa0;value are used to quantify heterogeneity, MR-Egger regression was used to evaluate the multilevel effect test of SNPs, and leave-one-out method to determine whether there are potential SNPs, and to evaluate the stability of the results. Odds ratio (OR) and 95% confidence interval (CI) were used as effect indicators to evaluate whether there is a&#xa0;causal relationship between GERD and mental disorders. RESULTS: IVW demonstrated a&#xa0;causal relationship between GERD and bipolar disorder (OR&#x202f;=&#x2009;1.70, 95%CI&#x202f;=&#x2009;1.39-2.09, P&#x202f;<&#x2009;0.05) and anorexia nervosa (OR&#x202f;=&#x2009;0.71, 95%CI&#x202f;=&#x2009;0.52-0.99, P&#x202f;<&#x2009;0.05). Furthermore, there is a&#xa0;weak causal relationship between GERD and major depression (OR&#x202f;=&#x2009;1.01, 95%CI&#x202f;=&#x2009;1.01-1.02, P&#x202f;<&#x2009;0.05) and anxiety (OR&#x202f;=&#x2009;1.01, 95%CI&#x202f;=&#x2009;1.01-1.01, P&#x202f;<&#x2009;0.05). Similarly, there is no evidence of a&#xa0;causal relationship between GERD and Alzheimer's disease (OR&#x202f;=&#x2009;0.95, 95%CI&#x202f;=&#x2009;0.87-1.03, P&#x202f;>&#x2009;0.05) or obsessive-compulsive disorder (OR&#x202f;=&#x2009;0.95, 95%CI&#x202f;=&#x2009;0.67-1.36, P&#x202f;>&#x2009;0.05). Cochran's Q&#xa0;test for heterogeneity shows that there is no significant heterogeneity (P&#x202f;>&#x2009;0.05) for bipolar disorder, anxiety, and obsessive-compulsive disorder. However, major depression, Alzheimer's disease, and anorexia nervosa have some degree of heterogeneity (P&#x202f;<&#x2009;0.05). Horizontal pleiotropic analysis showed that the P&#xa0;values for six mental disorders (0.750, 0.296, 0.154, 0.798, 0.893, 0.451) were all greater than 0.05. Leave-one-out analysis and funnel plot showed that MR analysis results can be considered relatively stable. All F are >&#x2009;10, indicating no weak IVs bias. CONCLUSION: GERD can obviously increase the risk of bipolar disorder; the increased risk of anxiety disorder is very slight. There is no clear evidence to support the causal relationship between GERD and four other mental disorders, including major depression, Alzheimer's disease, anorexia nervosa, and obsessive-compulsive disorder.

Humans↗

Role of HLA-DRA-CREB3L4 regulatory axis in the pathogenesis of ovarian endometriosis: Inhibition of CREB3L4 expression by HLA-DRA increases the risk of disease.

BACKGROUND: Ovarian endometriosis is a common gynecological condition characterized by the abnormal growth of endometrial-like tissue in locations outside the uterus, and its development remains poorly understood. This study aims to investigate potential protein regulatory networks and assess their impact on disease risk using both protein quantitative trait locus (pQTL) analysis and Mendelian randomization (MR) techniques. METHODS: This study systematically integrates two major genome-wide pQTL databases, UKB-PPP and deCODE, to identify pQTL signals associated with ovarian endometriosis. Additionally, we utilized the GEO database to validate differences in protein expression. We conducted a Mendelian randomization analysis to further explore the regulatory relationships between proteins and their roles in disease development. RESULTS: After the Bonferroni correction, we identified 33 pQTL signals from UKB-PPP and 19 pQTL signals from deCODE. Among these, 8 signals from UKB-PPP and 3 signals from deCODE were validated based on expression differences. The mediation analysis results indicate that HLA-DRA significantly increases the risk of developing ovarian endometriosis by inhibiting the expression of CREB3L4 (with a mediation proportion of 13.99&#x202f;%), and the direction of the mediation effect is consistent with the total effect. CONCLUSION: This study provides new insights that HLA-DRA downregulates the expression of CREB3L4, which may affect the risk of developing endometriosis. The results provide new evidence for understanding the genetic and molecular basis of ovarian endometriosis and establish a theoretical foundation for the development of future diagnostic markers and targeted treatment strategies.

Humans↗

Causal relationships between oral-gut microbiome and bone neoplasm-related phenotypes: Insights from bidirectional Mendelian randomization.

The human oral and gut microbiota are the 4 largest microbial communities in the body and play crucial roles in maintaining homeostasis and influencing disease. Observational studies have suggested links between these microbiota and bone neoplasm-related phenotypes, but establishing causality has been challenging due to confounding factors and reverse causality. We conducted a bidirectional, 2-sample Mendelian randomization (MR) study to investigate evidence consistent with a potential causal association between the saliva and gut microbiota and various bone neoplasm-related phenotypes. Genetic instruments for saliva and gut microbiota were sourced from large genome-wide association studies. Inverse variance weighted was the primary MR method, supplemented by 4 other MR techniques. Sensitivity analyses, including MR-Egger regression, were performed to assess pleiotropy and heterogeneity. In the forward MR analysis, Veillonella parvula from the saliva microbiota was associated with a decreased risk of bone and connective tissue neoplasms (&#x3b2;: -0.236, 95% CI: [-0.275, -0.197], P&#x2005;=&#x2005;8.20E-33). MR analyses identified genetically predicted associations between several microbial taxa and bone neoplasm-related phenotypes. Reverse MR analyses showed that genetic liability to bone neoplasm-related phenotypes was associated with variation in the composition of the oral (e.g., Order Bacteroidales, Rothia mucilaginosa) and gut microbiota (e.g., Class Methanobacteria, Genus Eubacterium oxidoreducens group). Sensitivity analyses confirmed the robustness of these findings, as no statistical evidence of substantial heterogeneity or directional horizontal pleiotropy was detected. This study provides genetic evidence supporting a bidirectional causal relationship between specific saliva and gut microbiota and bone neoplasm-related phenotypes. Our findings identify several microbial taxa as potential candidates for future biomarker development and therapeutic investigation in bone neoplasm-related phenotypes. However, these genetically informed associations require further mechanistic, experimental, and prospective clinical validation before clinical application.

Humans↗

A causal relationship between chronic pancreatitis and cardiovascular disease: A two-sample Mendelian randomization analysis.

Current research suggests a link between chronic pancreatitis (CP) and cardiovascular disease (CVD), although the causality remains unclear. The aim of this study was therefore to conduct a 2-sample Mendelian randomization (MR) analysis to determine whether a causal relationship exists between CP and CVD. Summary-level data from publicly available genome-wide association studies of European populations were utilized for the MR analysis. Following quality control measures, independent single-nucleotide polymorphisms associated with CP and CVD were chosen as the genetic instruments. Four complementary MR methods were performed, namely the inverse variance weighted (IVW) method, weighted median, MR-Egger, and leave-one-out sensitivity. The IVW method revealed correlations between alcohol-induced CP and myocardial infarction (odds ratio [OR]&#x2005;=&#x2005;1.001, 95% confidence interval [CI]: 1.000-1.002, P&#x2005;=&#x2005;.0010), as well as with large artery atherosclerosis stroke (OR&#x2005;=&#x2005;1.067, 95% CI: 1.030-1.105, P&#x2005;=&#x2005;.0003). The IVW method also suggested that CP was significantly associated with stroke (OR&#x2005;=&#x2005;1.040, 95% CI: 1.015-1.065, P&#x2005;=&#x2005;.0015) and with ischemic stroke (OR&#x2005;=&#x2005;1.041, 95% CI: 1.005-1.078, P&#x2005;=&#x2005;.0024). These results remained robust and consistent in the sensitivity analysis. This MR study indicates a significant causal relationship between alcohol-induced CP and elevated risks of myocardial infarction and large artery atherosclerosis stroke, and a causal link between CP and stroke as well as ischemic stroke.

Mendelian Randomization Analysis↗

Entertainment activities and the risk of multiple sclerosis: A Mendelian randomization analysis.

Modifying environmental and lifestyle factors may have the potential to prevent and ameliorate multiple sclerosis. Further elucidating the etiology of multiple sclerosis and proposing actionable prevention measures are of significant importance, but establishing causality in epidemiological data can be challenging. This study employed a two-sample Mendelian randomization analysis to evaluate the causal effect of entertainment activity factors on the risk of multiple sclerosis. Publicly accessible summary statistics derived from genome-wide association studies were utilized to assess 14 modifiable forms of entertainment activities. The inverse variance weighted random effects method was used as the primary analytical approach to estimate causal effects. Additionally, MR-Egger, weighted median, and weighted mode methods were applied to assess robustness. Systematic sensitivity analyses and heterogeneity tests were conducted to verify the reliability of our findings. We found that spending time outdoors in the summer may prevent the development of multiple sclerosis (odds ratio = 0.995; 95% confidence interval 0.991-0.999; P&#x2005;=&#x2005;.010). In contrast, the other entertainment activities studied showed no significant causal relationship with multiple sclerosis. Our results suggest that spending time outdoors in the summer may protect against the development of multiple sclerosis, providing implications for preventive measures against the disease.

Humans↗