SEARCH · PubMed Health

Results for “Mendelian Randomization Analysis”

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 91 records · Page 5Linked to original sources

PubMed2026

Causal Relationships Between Modifiable Risk Factors and Gastroesophageal Reflux Disease: A Two-Sample Mendelian Randomization Study.

INTRODUCTION: Gastroesophageal reflux disease (GERD) is a prevalent digestive disorder, yet the causal roles of modifiable risk factors remain unclear. This study aims to investigate the causal relationships between 28 modifiable risk factors (including obesity traits, mental health disorders, sleep traits, metabolic comorbidities, and serum parameters) and GERD using two-sample Mendelian randomization (MR). Gastroesophageal reflux disease (GERD). Our findings aim to inform targeted prevention and treatment strategies for GERD. METHODS: This study obtained data from extensive genome-wide association studies (GWAS). Pooled data associated with gastroesophageal reflux associations were obtained from the 23andMe Research team's research, which included a total of 129,080 cases of gastroesophageal reflux and 473,524 controls of European ancestry. We conducted a univariable Mendelian randomization (MR) analysis to ascertain whether genetic evidence of exposure demonstrated a statistically significant association with the risk of GERD. Subsequently, a multivariable MR analysis was carried out to estimate the independent effects of the exposures on GERD. RESULTS: Univariable MR analysis utilizing extensive GWAS data suggested that genetic factors such as BMI, Waist circumference, Arm fat mass (left and right), Leg fat mass (left and right), Attention Deficit and Hyperactivity Disorder (ADHD), Major Depressive Disorder (MDD), Schizophrenia, Negative emotions (including nervousness, anxiety, tension, or depression), Insomnia, Sleep apnea syndrome, Sleep duration, and Snoring, as well as Total cholesterol levels and Apolipoprotein B levels, are associated with the development of GERD. Multivariate Mendelian randomization of BMI and Negative emotion as correction factors showed that Waist circumference, Arm fat mass (left and right), Leg fat mass (left and right), ADHD, Insomnia, Sleep apnea syndrome, and Snoring were associated with an increased risk of GERD (p< 0.05). Conversely, longer sleep duration was associated with a reduced risk of GERD (p< 0.05). DISCUSSION: This MR study reveals novel causal mechanisms in GERD pathogenesis: (1) Peripheral adiposity (arm/leg fat mass) exerts independent effects beyond central obesity, indicating site-specific fat distribution significance; (2) ADHD emerges as a distinct psychiatric risk factor independent of mental disorders; (3) Sleep apnea operates through BMI-independent pathways. Collectively, these findings redefine GERD pathophysiology, highlighting fat depot specificity and brain-gut interactions as critical mechanistic drivers. CONCLUSION: Overall, our findings suggest that multiple risk factors are associated with the risk of GERD. These results provide a theoretical basis for controlling body weight and plasticity, improving sleep habits, and preventing and timely seeking medical attention to reduce the occurrence of psychiatric disorders, which will be important strategies to prevent and alleviate GERD.

Humans↗

PubMed2026

Exploring the Genetic Link between Irritable Bowel Syndrome and Polycystic Ovary Syndrome: Bidirectional Mendelian Randomization and Machine Learning Approaches.

BACKGROUND: Research has shown a certain correlation between polycystic ovary syndrome (PCOS) and irritable bowel syndrome (IBS). The study aims to determine the directionality and underlying biological processes influencing the relationship between these two disorders. METHODS: We explored the causal relationship between IBS and PCOS by conducting a comprehensive bidirectional Mendelian randomization (MR) analysis using five different methods and conducted robustness assessments. We extracted differentially expressed genes from the IBS and PCOS datasets for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Additionally, we developed a protein-protein interaction (PPI) network and applied the Least Absolute Shrinkage and Selection Operator (LASSO) and Support Vector Machine (SVM) methodologies to pinpoint key diagnostic markers. Diagnostic efficacy was further assessed through Receiver Operating Characteristic (ROC) curve analysis for selected genes. Finally, single-sample gene set enrichment analysis (ssGSEA) was carried out to examine immune cell infiltration in IBS and PCOS. RESULTS: MR analysis identified a causal effect of PCOS on IBS (IVW, OR = 1.034, 95% CI: 1.003-1.065, P = 0.029). Conversely, no relationship between IBS and PCOS was observed in the reverse analysis. Furthermore, integrative bioinformatics and machine learning analyses identified CD14 and CASP1 as key diagnostic biomarkers for both IBS and PCOS, which were significantly associated with immune cell infiltration. CONCLUSION: MR analysis has demonstrated a significant positive causal relationship between PCOS and IBS, though the reverse causality from IBS to PCOS appeared non-significant. The genes CD14 and CASP1 emerged as potential shared diagnostic markers between these two conditions.

Polycystic Ovary Syndrome↗

PubMed2025

Association between NAFLD and liver cancer: A two-sample Mendelian randomization study.

Observational studies suggest an association between nonalcoholic fatty liver disease (NAFLD) and liver cancer, but its causal nature remains unclear. A 2-sample Mendelian randomization (MR) analysis was performed using NAFLD and liver cancer summary statistics from genome-wide association study databases. Instrumental variables satisfying the 3 core MR assumptions were selected. Causal effects were estimated using inverse-variance weighted, MR-Egger, weighted median, and other methods, followed by sensitivity and power analyses. All 4 MR analyses demonstrated a positive causal association between NAFLD and liver cancer risk [odds ratio > 1, inverse-variance weighted P < .001]. Sensitivity analysis indicated no significant level of multiplicity or heterogeneity in the instrumental variables, and individual single nucleotide polymorphisms had no significant impact on the results. However, statistical power was insufficient. This study provides the first MR evidence demonstrating a genetically predicted causal relationship between NAFLD and liver cancer that is consistent across subtypes. Sensitivity analyses confirmed the absence of horizontal pleiotropy or heterogeneity, strengthening the robustness of the findings. These results offer genetic support for early NAFLD intervention to reduce the risk of liver cancer. However, the limited statistical power highlights the need for larger-scale genome-wide association study to identify more and stronger genetic instruments for a more precise quantification of the causal effect of NAFLD on liver cancer risk.

Humans↗

PubMed2026

Ferroptosis as a mediator of gut microbiota-driven inflammatory bowel disease: Evidence from genetic analyses.

Gut microbiota dysbiosis is increasingly recognized as a contributor to inflammatory bowel disease (IBD), yet causal relationships and underlying mechanisms remain unclear. Ferroptosis, an iron-dependent form of regulated cell death, plays a key role in epithelial barrier damage and inflammation. This study aimed to determine whether specific gut microbial taxa are causally associated with IBD and whether ferroptosis-related genes mediate this association using Mendelian randomization (MR). Two-sample MR and mediation MR analyses were performed using genome-wide association study summary data from the FinnGen consortium (IBD), the genome-wide association study catalog (473 gut microbial taxa), and the deCODE database (ferroptosis-related genes). Instrumental variables were selected with thresholds of P < 1 × 10-6 for microbes and P < 5 × 10-8 for traits, and linkage disequilibrium clumping (r2 < 0.001) was applied. Twenty-three microbial taxa showed significant causal associations with IBD (e.g., Chromatiales, OR = 0.51; Acetobacterales, OR = 2.61). Several ferroptosis-related genes were linked to IBD risk (e.g., GPX4, STAT3, IDO1). Mediation MR revealed that genes such as MUC1, IDO1, and ADAM23 partially mediated microbial effects on IBD, with mediation proportions up to 7.6%. This study provides novel genetic evidence supporting a gut microbiota-ferroptosis-IBD axis. Ferroptosis-related pathways may partially mediate microbial effects on IBD pathogenesis and represent promising targets for future therapeutic interventions.

Ferroptosis↗

PubMed2026

Investigating the causal effects of physical activity and sedentary behavior on hernia risk: A two-sample Mendelian randomization approach.

The global prevalence of hernia is increasing, particularly due to the aging population. Although physical activity and sedentary behavior are known to influence various health outcomes, their specific roles in hernia development remain inadequately investigated. This study aimed to systematically assess the causal relationships between physical activity, sedentary behavior, and the risk of hernia development using Mendelian randomization (MR) analysis. We used genome-wide association study data from the UK Biobank and FinnGen Biobank to explore the causal effects of sedentary behavior on hernia risk via 5 distinct MR approaches. To ensure the reliability of our risk models, we performed sensitivity analyses, including Cochran's Q test, MR-Egger intercept analysis, leave-one-out analysis, and funnel plots. Furthermore, we employed multivariable MR analysis to determine the independent causal effects of both physical activity and sedentary behavior. Our findings indicate that moderate-to-vigorous physical activity (MVPA) was significantly associated with an increased risk of inguinal hernia, with an odds ratio of 1.844 (95% confidence interval, 1.181-2.879; P = .007). Associations between sedentary behavior and diaphragmatic or umbilical hernia were inconsistent across methods and were sensitive to pleiotropy; thus, no robust causal relationship was established. Multivariable MR analysis further confirmed the independent and significant causal relationship between MVPA and inguinal hernia, with an odds ratio of 1.901 (95% confidence interval, 1.098-3.291; P = .022). Our study highlights a significant association between MVPA and an increased risk of inguinal hernia, suggesting that physical activity should be carefully considered in preventive strategies for hernias. However, the relationship between sedentary behavior and hernia development warrants further investigation.

Mendelian Randomization Analysis↗

PubMed2025

Genetic predisposition to systemic inflammatory proteins is causally associated with inflammatory bowel disease: Insights from multi-omics association study and single-cell RNA-sequencing analysis.

Systemic inflammatory proteins have been reported to be related to inflammatory bowel disease (IBD) in previous observational research. However, their causal links remain obscure. Herein, we performed a Mendelian randomization (MR) analysis to analyze the causality between systemic inflammatory proteins and IBD. Genetic variants related to systemic inflammatory proteins were extracted from a meta-analysis of genome-wide association study (GWAS) data of 8293 European participants. Summary statistics of IBD diverse subtypes were obtained from the international IBD genetic consortium (IIBDGC). We conducted multi-omics method and MR study to detect the causal links through integrating GWAS and protein quantity trait loci (pQTL) data. Inverse variance weighted (IVW) approach was utilized as the dominated analysis method. Moreover, complementary approaches such as MR-Egger intercept test, Cochran Q test and leave-one-out analysis were utilized to validate pleiotropy and heterogeneity. Finally, single-cell RNA-sequencing analysis was performed to detect the expression of significant genes. For IBD, IVW estimates suggested that genetically predicted IL-10 and IL-13 were suggestively associated with an elevated risk of IBD (IL-10: OR: 1.12, 95% CI: 1.00-1.24, P = .04; IL-13: OR: 1.09, 95% CI: 1.01-1.18, P = .023), while CXCL10 was suggestively linked to a lower risk of IBD (CXCL10: OR: 0.90, 95% CI: 0.82-0.99, P = .037). For Crohn disease (CD), the IVW approach provided evidence to sustain that genetically determined IL-13 and CCL3 had a suggestive association with a higher risk of CD (IL-13: OR: 1.13, 95% CI: 1.02-1.26, P = .023; CCL3: OR: 1.22, 95% CI: 1.03-1.45, P = .018). Sensitivity analysis did not explore any heterogeneity and pleiotropy. Our findings supported the causal relationships between 4 specific inflammatory proteins (IL-10, IL-13, CXCL10, and CCL3) and the risk of IBD and CD, thereby providing promising biomarkers of various subtypes stratification and new insights for the prevention and therapeutic target of IBD.

Humans↗

PubMed2026

Toxicological effects of propyl 4-hydroxybenzoate on gallstone pathogenesis: An integrated mendelian randomization, network toxicology, and experimental study.

BACKGROUND: Gallstone disease is a prevalent digestive disorder with substantial global socioeconomic burden. Propyl 4-hydroxybenzoate (PP), a widely used paraben preservative, exhibits potential metabolic and hepatic toxicity, yet its role in gallstone pathogenesis remains unclear. This study aimed to explore the causal association between PP exposure and gallstone formation and the underlying mechanism. METHODS: Two-sample Mendelian randomization (MR) was performed using genome-wide association study (GWAS) data. Network toxicology, molecular docking, and molecular dynamics simulation were applied to screen for core targets. In vivo experiments, transcriptome sequencing, Western blot (WB), and ELISA were conducted for mechanistic validation. RESULTS: MR confirmed a causal link between circulating PP levels and an elevated risk of gallstones (P < 0.05), with AKT1 identified as the key target. In mice, PP aggravated gallstone formation by activating the AKT1-NF-κB-CXCL1 pathway, enhancing hepatic inflammation and neutrophil extracellular traps (NETs) formation; these effects were reversed by AKT inhibition. CONCLUSION: PP promotes gallstone formation via the AKT1-NF-κB-CXCL1-NETs axis. Our findings highlight PP as an environmental risk factor for gallstones, providing novel insights into their prevention and targeted therapy.

Animals↗

PubMed2025

Severe traumatic brain injury and risk for osteoporosis: a Mendelian randomization study.

BACKGROUND: The influence of nervous system activity on bone remodeling has been widely reported. Patients with traumatic brain injury (TBI) exhibit a high incidence of osteoporosis (OP). Nevertheless, the relationship between severe TBI (sTBI) and OP remains unclear. We performed Mendelian randomization (MR) analysis to assess the potential causal relationship between sTBI and OP. METHODS: Data on exposure and outcomes were acquired from genome-wide association studies (GWAS). Data on OP was obtained from UK Biobank (5,266 cases of OP and 331,893 controls). Data on sTBI was obtained from FinnGen Consortium (6,687 cases and 370,590 controls). Single nucleotide polymorphisms (SNPs) that underwent strict screening were regarded as instrumental variables. We used the inverse variance weighted (IVW), constrained maximum likelihood and model averaging (CML-MA), MR-Egger, and weighted median methods for causal effect estimation. To test the reliability of the results, sensitivity analysis was performed using Cochran's Q, leave-one-out, MR-Egger intercept, and MR Pleiotropy RESidual Sum and Outlier (MR-PRESSO) tests. RESULTS: The IVW analysis indicates that sTBI and OP have a suggestive association (odds ratio [OR] = 1.004, 95% confidence interval [CI] = 1.001,1.007; p = 0.002), and no heterogeneity (Q = 11.536, p = 0.241) or directional pleiotropy was observed (egger_intercept = 7.368 × 10- 5, p = 0.870). The robustness of the results was validated using a leave-one-out sensitivity test. CONCLUSION: According to the MR analysis, sTBI and OP are likely suggestively related. This finding contributes to the prevention of OP in patients with sTBI and provides genetic evidence supporting the theory that the nervous system regulates bone remodeling.

Humans↗

PubMed2025

The role of the brain-bone axis in skeletal degenerative diseases and psychiatric disorders, A genome-wide pleiotropic analysis.

INTRODUCTION: Skeletal degenerative diseases and psychiatric disorders often coexist clinically. However, the genetic correlations and underlying biological mechanisms between these two types of diseases remain unclear. OBJECTIVES: To investigate the genetic correlations between skeletal degenerative diseases and psychiatric disorders and to identify shared genomic loci, genes, and pathways. METHODS: This comprehensive genome-wide pleiotropic association study utilized summary statistics from publicly available genome-wide association data. Various statistical genetic correlation methods were employed, including LDSC, HDL, PLACO, Coloc, Hyprcoloc, and Mendelian randomization (MR) analysis, along with immune cell colocalization analysis. The study aimed to identify potential shared genetic factors among three skeletal degenerative diseases (osteoarthritis, intervertebral disc degeneration, and osteoporosis) and three psychiatric disorders (schizophrenia, anxiety disorder, and major depressive disorder). RESULTS: Analyses using LDSC, HDL, and Bonferroni corrections revealed significant genetic correlations between intervertebral disc degeneration (IVDD) and anxiety disorder (ANX); fractures, IVDD, and arthritis with major depressive disorder (MDD); and arthritis with schizophrenia (SCZ). Significant genetic correlations were also observed between VDD and ANX, fractures, IVDD, hip osteoarthritis (HipOA), knee osteoarthritis (KneeOA) and MDD, and KneeOA and SCZ. Pleiotropy analysis using PLACO, MAGMA, and multitrait colocalization Hyprcoloc identified 65 pleiotropic loci, 27 shared causal loci, and 9 shared risk loci involving immune cells related to both psychiatric and bone-related diseases. Additionally, tissue-specific enrichment analysis showed that genes mapped to these loci were enriched in brain, cardiovascular, pancreatic, and other tissues. The IVW method demonstrated that MDD increased the risk of IVDD and KneeOA, while IVDD increased the risk of ANX and MDD. Conversely, SCZ was associated with a reduced risk of KneeOA. Multiple sensitivity analyses further supported a positive causal effect of IVDD on MDD. CONCLUSION: These findings suggest significant genetic correlations between skeletal degenerative diseases and psychiatric disorders, highlighting multiple shared comorbid genes and key immune cell types. Importantly, the study supports the role of the brain-bone axis in the regulation of skeletal degenerative diseases and psychiatric disorders, which could provide valuable insights for potential therapeutic targets and interventions for these conditions.

Humans↗

PubMed2025

Alterations of gut microbiome in chronic rhinosinusitis: insights from a mendelian randomization study.

OBJECTIVE: Gut microbiome dysbiosis is associated with various diseases. Causal association between Chronic Rhinosinusitis (CRS) and gut microbiome is yet unknown. This study aimed to investigate the potential causal relationship between CRS and gut microbiome dysbiosis. METHODS: We used Genome-Wide Association Study (GWAS) data from FinnGen database for CRS. The Dutch Microbiome Project study provided data on gut microbiota species. A total of 334,182 individuals were included. Two-sample bidirectional Mendelian Randomization (MR) analysis was used to investigate causal relationship between CRS and gut microbiome. The main methods of evaluation were Inverse Variance Weighting (IVW), weighted median, weighted mode, and MR-Egger regression. Sensitivity analyses were performed to assess heterogeneity and pleiotropy. RESULTS: Forward MR analysis indicated CRS is potentially linked to decreased risk of Haemophilus parainfluenzae (OR = 0.79, 95% CI 0.66‒0.94, p = 0.009) and increased risk of Bilophila's (OR = 1.14, 95% CI 1.02-1.27, p = 0.023) within the gut. Reduced risks in gut microbiota-related pathways like UDP-N-acetyl-d-glucosamine biosynthesis I (OR = 0.85, 95% CI 0.77‒0.94, p = 0.002) and increased risk in pathway NAD biosynthesis I from aspartate (OR = 1.14, 95% CI 1.03-1.27, p = 0.010) were also linked to CRS. Reverse MR analyses, we obtained no positive results (p > 0.05/412). CONCLUSION: This study reveals CRS exerts a causal impact on shifts within the composition of the gut microbiome and also links to the changes of gut microbiota-related metabolic pathways. The risk of changes in gut microbiota should be of greater concern in patients with CRS than in the general population. LEVEL OF EVIDENCE: Mendelian Randomized (MR) studies are second only to randomized controlled trials in terms of the level of evidence.

Humans↗

PubMed2026

Single-Cell Transcriptome-Wide Mendelian Randomization and Colocalization Uncover Potential Immunocytes-Related Therapeutic Targets for Obesity.

Weight-loss treatment is crucial for individuals with obesity to prevent various complications. The role of Immune cells in obesity has been recently recognized, whereas its translation into therapy requires identifying key target genes. We performed Mendelian randomization (MR) analysis to assess causal relationships between expression quantitative trait loci (eQTL) of 14 immune cells and obesity-related traits (obesity, body mass index and body fat percentage), and validated the results in colocalization analysis. For the putative causal genes identified by the MR and colocalization analyses, we conducted pathway enrichment, differential expressed gene (DEG) analysis and search of druggable evidence, and utilized a Tier system to prioritize drug targets for obesity. MR and colocalization evidence was observed for 1630 genes associated with one or more obesity-related traits, mainly expressed in CD4+ naive/central memory T cells and enriched in antigen processing and presentation pathways. Forty-one genes showed causal relationship with all three outcomes, among which 19 genes have not been reported for obesity previously. DEG analysis using single-cell RNA sequencing data of blood or adipose tissue indicated that the differential expression of UBE2Z in monocytes, ZCCHC7 in T cells, and FNBP4 in B cells between lean and obese individuals were consistent with the MR results. By searching drug-gene interaction databases, we found targeted drugs for PYGB and PRUNE1, and PYGB was the top gene ranked in the Tier system. This study provides evidence for the involvement of immune cells in obesity, and the potential cell-specific, immune-related targets for obesity treatment.

Obesity↗

PubMed2025

Psychological Resilience and Mental Wellbeing Mitigate the Risk of Irritable Bowel Syndrome.

INTRODUCTION: Comorbidities between mental disorders and irritable bowel syndrome (IBS) have been widely reported, yet associations between mental wellbeing and IBS, particularly regarding underlying genetic modification and proteomic signatures, remain underexplored. METHODS: This prospective cohort study analyzed 75,842 IBS-free participants aiming to investigate the prospective association between mental wellbeing and the risk of IBS in UK Biobank. Mental wellbeing was assessed through life satisfaction, positive affect, neuroticism, and depressive/anxiety symptoms. Cox models evaluate the hazard ratio (HR) for mental wellbeing and plasma proteome in relation to incident IBS during follow-up. Proteomic profiling identified mental wellbeing-associated proteins, with pathway enrichment analysis revealing biological mechanisms. Mediation and Mendelian randomization analyses further examine intermediate pathways and causality. RESULTS: With a 12.4-year follow-up period, 1,400 cases of incident IBS were documented. Better mental wellbeing mitigated IBS risk dose-dependently (low risk group: HR, 0.37; 95% confidence interval [CI]: 0.31-0.43). Higher life satisfaction (HR, 0.41; 95% CI: 0.30-0.56) and positive affect (HR, 0.50; 95% CI: 0.41-0.62) were inversely associated with IBS risk, whereas neuroticism (HR, 2.35; 95% CI: 1.92-2.88) and depressive/anxiety symptoms (HR, 3.09; 95% CI: 2.17-4.42) increased the risk. Findings remained consistent in across prevalent IBS and IBS subtypes. Mental wellbeing effects were independent of genetic predisposition. Mediation analyses revealed about 27% of protective effect of mental wellbeing were mediated through reduced depression and anxiety. Mendelian randomization supports causal protective effects of positive mental wellbeing on IBS. Proteomic profiling identified mental wellbeing-associated proteins mainly enriched in cytokine-cytokine receptor interactions. Chromogranin A and gastrin emerged as key protein biomarkers, showing significant associations with both mental wellbeing components and IBS risk. DISCUSSION: Our study demonstrates that enhanced mental wellbeing confers substantial protection against IBS development, highlighting psychological interventions as potential primary prevention strategies.

Humans↗

PubMed2026

Genetic Evidence That Stroke Causally Increases Circulating PDGFB Levels: a Two-Sample Mendelian Randomization Study.

Platelet-derived growth factor subunit B (PDGFB) is a key regulator of vascular remodeling, angiogenesis, and blood-brain barrier integrity. Although elevated PDGFB levels have been reported after ischemic injury, whether stroke liability itself causally influences circulating PDGFB levels remains unclear. We performed a two-sample Mendelian randomization (MR) analysis to assess the causal effects of genetically predicted all stroke, ischemic stroke, and cardioembolic stroke on plasma PDGFB concentrations. Genetic instruments were obtained from large-scale GIGASTROKE genome-wide association studies, and outcome data were derived from a proteomics GWAS. Instruments were then filtered by removing variants associated with established cardiovascular risk factors in a phenome-wide screen and outliers identified by RadialMR. The inverse variance-weighted (IVW) method was used as the primary analysis, complemented by weighted median, weighted mode, and MR-Egger approaches. Sensitivity analyses included Cochran's Q statistics, MR-Egger intercept tests, single-SNP analyses, leave-one-out analyses, and MR-PRESSO. IVW analysis demonstrated a significant positive causal association between genetic liability to all stroke and plasma PDGFB levels (β = 0.209, SE = 0.062, 95% CI 0.088 to 0.331, p = 7.3 × 10-4). A similar association was observed for ischemic stroke (β = 0.155, SE = 0.059, 95% CI 0.039 to 0.270, p = 0.009), with directionally consistent results across sensitivity analyses. MR-Egger regression for ischemic stroke initially suggested pleiotropy.After removal of a radial-MR outlier (rs2289252), the intercept was attenuated and no longer statistically significant (- 0.0190, p = 0.282). In contrast, no evidence of a causal association was found between cardioembolic stroke liability and plasma PDGFB levels across all MR methods (β = - 0.078, SE = 0.087, 95% CI - 0.248 to 0.092, p = 0.368). These findings provide genetic evidence that liability to stroke, particularly ischemic stroke, is causally associated with increased circulating PDGFB levels, whereas cardioembolic stroke does not show such an effect. This suggests that elevated PDGFB reflects vascular responses specific to ischemic stroke rather than a general consequence of all stroke subtypes.

Humans↗

PubMed2026

The causal relationships and potential pathways between birth weight and cardiovascular diseases: A human genomics study.

The causal relationships and potential pathways between birth weight (BW) and various cardiovascular diseases (CVDs) remain unclear, particularly when discriminating maternal and fetal contributions of BW to CVDs. Leveraging the genome-wide association studies (GWASs) of BW (N = 321,223) and a range of CVDs (ncases = 43,676-181,522), we performed a 2-sample Mendelian randomization (MR) analysis to estimate the causal effect of BW, fetal-specific BW, and maternal-specific BW on coronary artery disease (CAD), myocardial infarction (MI), heart failure (HF), atrial fibrillation (AF), and stroke. Furthermore, we applied a stepwise MR analysis approach to assess the potential involvement of childhood body mass index (CBMI) and age at menarche (AAM) in the causal pathways from BW to CVDs, while considering adult BMI. Finally, we performed colocalization analyses to justify the different biological mechanisms of maternal-specific and fetal-specific BW. The 2-sample MR analysis revealed that genetically predicted higher BW per standard deviation (SD) was associated with a decreased risk of CAD (odds ratio [OR] = 0.804, 95% confidence interval [CI]: 0.731-0.883), MI (OR = 0.720, 95% CI: 0.638-0.814), and stroke (OR = 0.900, 95% CI: 0.823-0.985), but an increased risk of AF (OR = 1.279, 95% CI: 1.160-1.410). Similar associations were observed for fetal-specific/maternal-specific BW. The stepwise MR analysis indicated that CBMI and AAM could serve as factors linking BW/fetal-specific BW and CVDs, albeit in different roles, by displaying an indirect causal effect through adult BMI. However, for maternal-specific BW, our results failed to support a causal effect on CBMI or AAM. Colocalization analyses supported the distinct biological mechanisms for maternal-specific and fetal-specific BW by showing different causal genes. The study suggested that both fetal genotype and intrauterine environmental exposure contribute to the causal associations. Additionally, AAM and CBMI may play a role in the pathways linking BW and CVDs, though the effect was only observed for fetal-specific BW.

Humans↗

PubMed2024

Causal effect of the age at first birth with depression: a mendelian randomization study.

BACKGROUND: This study aimed to explore the causal relationship between age at first birth (AFB) and depression. METHODS: Using the univariable Mendelian randomization (UVMR) and multivariable Mendelian randomization (MVMR) methods to examine the potential correlation between age at first birth (AFB) and major depressive disorder and postpartum depression. A public database was used to obtain the genome-wide association studies (GWAS) summary data. We put inverse-variance-weighted (IVW) as the primary method in Mendelian randomization (MR) analysis and used sensitivity analysis to confirm the robustness of our result. RESULTS: We found a significant causal association between AFB and major depressive disorder by using the IVW algorithm (odd ratio [OR] 0.826; 95% confidence interval [CI] 0.793 - 0.861; P = 4.51 × 10- 20). MR-Egger, weighted median, simple mode and weighted mode method concluded the same result (P < 0.05). During the sensitivity analysis, the heterogeneity test (Q-value = 55.061, df = 48, P = 2.81 × 10- 01, I2 = 12.82%) and the leave-one-out plot analysis confirmed the stability of the results. The outcomes of the pleiotropy test (MR-Egger intercept = 8.932 × 10- 3. SE = 6.909 × 10- 3. P = 2.02 × 10- 01) and MR_PRESSO global test (P = 2.03 × 10- 01) indicated there is no pleiotropy. CONCLUSION: There is solid evidence that a higher age at first birth is associated with a lower risk of major depressive disorder.

Humans↗

PubMed2026

Subtype-Specific Causal Effects of C16 and C24 Ceramides on Heart Failure: Evidence From Univariable and Multivariable Mendelian Randomization Analyses.

Ceramides (Cer) are bioactive lipids implicated in cardiovascular disease (CVD), yet their subtype-specific causal effects remain unclear. We performed a two-sample Mendelian randomization (MR) analysis using publicly available GWAS summary statistics to investigate the effects of C16:0-ceramide homologs (Cer16:0) and C24:1-ceramide homologs (Cer24:1) on six CVD outcomes. Instrumental variables were rigorously selected, and multiple MR methods were applied to ensure robust inference. Univariable MR identified a significant inverse association between Cer(d18:1/24:1) and heart failure (HF), which remained significant after false discovery rate correction. In contrast, the association for Cer(d17:1/16:0) did not remain significant after correction. No causal associations were observed for other CVD outcomes. When aggregating subtypes, genetically predicted higher total Cer16:0 levels were associated with increased HF risk, while no significant association was found for total Cer24:1. Multivariable MR further demonstrated that the protective effect of Cer(d18:1/24:1) on HF was robust, while estimates for C16 subtypes were attenuated and sensitive to model specification. In conclusion, our findings support a stable protective role of Cer(d18:1/24:1) in HF and highlight the complexity of subtype-specific effects among structurally related ceramides. These results underscore the importance of considering ceramide heterogeneity in cardiovascular research. Further studies are warranted to validate these findings and explore their clinical implications.

Ceramides↗

PubMed2026

Genetically predicted associations between blood cell perturbation responses and bronchiectasis through immune mediation: A Mendelian Randomization study.

BACKGROUND: Bronchiectasis is a chronic airway disease characterized by persistent inflammation and structural damage, with substantial clinical and etiologic heterogeneity. Although previous studies have identified associations between blood cells and bronchiectasis, the causal relationships remain unclear. Moreover, the mechanisms underlying blood cell perturbation responses and their potential mediation by immune cells in disease progression are largely unexplored. METHODS: Two-sample Mendelian randomization (MR) analysis was used to explore genetically predicted associations among immune cell traits, blood cell perturbation response phenotypes, and bronchiectasis, based on genome-wide association study summary data. Mediation MR analysis was further applied to assess whether immune cells mediate these associations. Multiple sensitivity analyses, including tests for heterogeneity and horizontal pleiotropy, were performed to evaluate the validity and robustness. RESULTS: Five blood cell perturbation response phenotypes and twenty-nine immune cell traits showed significant genetically predicted associations with bronchiectasis. Mediation analysis showed that natural killer (NK) cell absolute count partially mediated the causal effect between the eosinophil perturbation response and bronchiectasis, with a mediation proportion of 9.626%. CD38 on transitional B cells mediated the causal effect between the monocyte perturbation response and bronchiectasis, with a mediation proportion of 10.580%. Additionally, CD45 on NK cells played a mediating role in the association between the white blood cell perturbation response and bronchiectasis, with a mediation proportion of 10.651%. CONCLUSION: This study systematically explores genetically predicted associations between blood cell perturbation responses and bronchiectasis and highlights potential immune-mediated pathways. These exploratory findings provide novel genetic insights into the pathogenesis of bronchiectasis and identify potential therapeutic targets for future strategies.

Humans↗

PubMed2026

Causal relationships between psoriasis and coronary artery disease: A two-sample Mendelian randomization study.

Previous studies have revealed a potential association between psoriasis and coronary artery disease (CAD). However, the causal relationship between the 2 remains unclear. This study aims to assess the causal link between psoriasis and CAD, which encompasses coronary heart disease, myocardial infarction, and angina pectoris. After obtaining genome-wide association studies data on psoriasis and CAD, we selected appropriate single nucleotide polymorphisms for Mendelian randomization (MR) analysis. The inverse-variance weighted method was used as the main analytical method. The inverse-variance weighted method indicated that psoriasis was associated with a higher risk of CAD (odds ratio = 11.538, 95% confidence interval = 4.498-29.595, P < .001), and coronary heart disease (odds ratio = 1.080, 95% confidence interval = 1.031-1.132, P = .001). Reverse MR analyses did not show causal effects of CAD on psoriasis. This study shows a significant causal association between psoriasis and incidence of CAD. However, there is no reverse causal association between CAD and psoriasis.

Psoriasis↗