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Lipid-lowering drugs and risk of rapid renal function decline: a mendelian randomization study.

BACKGROUND: Chronic kidney disease (CKD) patients face the risk of rapid kidney function decline leading to adverse outcomes like dialysis and mortality. Lipid metabolism might contribute to acute kidney function decline in CKD patients. Here, we utilized the Mendelian Randomization approach to investigate potential causal relationships between drug target-mediated lipid phenotypes and rapid renal function decline. METHODS: In this study, we utilized two methodologies: summarized data-based Mendelian randomization (SMR) and inverse variance-weighted Mendelian randomization (IVW-MR), to approximate exposure to lipid-lowering drugs. This entailed leveraging expression quantitative trait loci (eQTL) for drug target genes and genetic variants proximal to drug target gene regions, which encode proteins associated with low-density lipoprotein (LDL) cholesterol, as identified in genome-wide association studies. The objective was to investigate causal associations with the progression of rapid kidney function decline. RESULTS: The SMR analysis revealed a potential association between high expression of PCSK9 and rapid kidney function decline (OR = 1.11, 95% CI= [1.001-1.23]; p = 0.044). Similarly, IVW-MR analysis demonstrated a negative association between LDL cholesterol mediated by HMGCR and kidney function decline (OR = 0.74, 95% CI = 0.60-0.90; p = 0.003). CONCLUSION: Genetically predicted inhibition of HMGCR is linked with the progression of kidney function decline, while genetically predicted PCSK9 inhibition is negatively associated with kidney function decline. Future research should incorporate clinical trials to validate the relevance of PCSK9 in preventing kidney function decline.

Mendelian Randomization Analysis↗

Two-sample Mendelian randomization study of gut microbiota and inflammatory proteins: Predictive, preventive, and personalized treatment for migraine.

The human gut microbiota is increasingly recognized as a significant factor in the pathogenesis of migraine, potentially via inflammatory pathways. Identifying specific human gut microbiota components associated with migraines, along with the investigation of particular inflammatory proteins, is essential for advancing primary prediction, targeted prevention, and personalized treatment strategies for migraines. We conducted a two-sample Mendelian randomization study using publicly available summary statistics from genome-wide association studies. Data for 473 human gut microbiota taxa were obtained from the Finnish national health survey conducted by the National Institute for Health and Welfare study (FINRISK, n = 5959 European participants). Genome-wide association study data (https://www.ebi.ac.uk/gwas/) for 91 circulating inflammatory proteins were obtained from 14,824 participants across 11 cohorts using the Olink Target 96 Inflammation panel. Migraine outcome data were obtained from the FinnGen R12 release, with cases defined using ICD-10 code G43. All genome-wide association study analyses were adjusted for sex, age, genotyping batch, and 10 genetic principal components to control population stratification (genomic inflation factors: 1.00–1.05). Inverse variance-weighted Mendelian randomization was the primary analysis method, with Mendelian randomization-Egger, weighted median, and mode-based methods as sensitivity analyses. Two-step Mendelian randomization mediation analysis quantified the proportion of the effects of human gut microbiota on migraine that are mediated through inflammatory proteins. Thirty-seven bacterial genera were found to be associated with migraine using the inverse variance-weighted method. Of these, 18 genera exhibited a negative association, while 19 genera demonstrated a positive association with migraine risk. Additionally, eight inflammatory proteins were found to increase the risk of migraine. Among human gut microbiota, four were observed to reduce inflammatory protein levels, whereas another four were associated with increased inflammatory protein levels. Additionally, five gut microbiota were identified to influence migraine through inflammatory proteins in both Mendelian randomization analyses. Specifically, Actinobacteria, Brachyspiraceae, CAG-269 sp001915995, and Paraglaciecola were found to affect migraine outcomes via inflammatory proteins, with mediation proportions of 12%, 19%, 15.5%, and 6.7%, respectively. Lawsonibacter sp002161175 was identified to influence migraine risk through Oncostatin-M and SLAM, with mediation proportions of 15.6% and 11.3%, respectively. Our study elucidated the role of specific human gut microbiota alterations in the pathogenesis of migraine and highlighted the mediating effects of inflammatory proteins. Targeting these particular human gut microbiota alterations offers a promising strategy for predictive, preventive, and personalized medicine in migraine management, resulting in substantial clinical advancements.

causality↗

Deciphering miRNA-mediated genetic architecture of immune cell subsets in hypertrophic scars and keloids: A 2-step Mendelian randomization study unveiling causal associations.

This study aimed to investigate the potential causal roles of specific circulating microRNAs (miRNAs) and immune cell subsets in the pathogenesis of hypertrophic scars and keloids using a 2-step Mendelian randomization framework. We employed a 2-sample Mendelian randomization approach to evaluate the causal relationships between miRNAs, immune cell genotypes, and scar phenotypes. The analysis integrated miRNA expression quantitative trait loci, immune cell genome-wide association studies, and scar datasets. A 2-step mediation analysis was conducted to assess the indirect effects of miRNAs on scars through immune cell genotypes, using inverse variance weighted methods and complementary sensitivity analyses to ensure robustness. Our analysis identified significant associations between specific miRNAs and scar phenotypes. Notably, miR-6887-5p exhibited a total effect on keloid formation risk (β = 0.324, 95% confidence interval [CI]: 0.073-0.576) and a direct effect (β = 0.283, 95% CI: 0.027, 0.538), with a marginally significant mediation effect through B-cell activating factor receptor on CD20- CD38- B cells (β = 0.042, 95% CI: -0.001, 0.084, P = .047). For hypertrophic scars, miR-345-5p demonstrated a significant total effect (β = -0.501, 95% CI: -0.903, -0.099) and direct effect (β = -0.469, 95% CI: -0.872, -0.066), with a significant mediation effect through CD28+ CD45RA- CD8dim T cell percentage (β = -0.032, 95% CI: -0.062, -0.002, P = .034). miR-4801 showed a significant total effect (β = -0.246, 95% CI: -0.429, -0.064) and direct effect (β = -0.218, 95% CI: -0.402, -0.033), with a marginally significant mediation effect through T cell absolute count (β = -0.028, 95% CI: -0.057, -0.000, P = .043). These findings highlight the interplay between miRNAs and immune cell subsets in scar pathogenesis. This study provides preliminary evidence for the causal roles of specific miRNAs and immune cell subsets in scar formation, emphasizing the potential of miRNA-immune cell axes as therapeutic targets. While the identified associations offer important insights into the molecular mechanisms of scar heterogeneity, further validation through mechanistic studies and clinical trials is necessary to translate these genetic insights into clinical interventions.

Humans↗

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↗

Assessing the causal association between celiac disease and Alzheimer disease and frontotemporal dementia: A bidirectional Mendelian randomization approach.

This study aimed to investigate the bidirectional causal relationship between celiac disease (CD) and the risk of Alzheimer disease (AD) or frontotemporal dementia (FTD) using Mendelian randomization (MR), in order to clarify prior inconsistent findings. We analyzed summary-level genome-wide association study (GWAS) data for CD, AD, and FTD. Single-nucleotide polymorphisms (SNPs) strongly associated with each condition were selected as genetic instruments. MR analysis was conducted in 2 directions: from CD to AD/FTD and from AD/FTD to CD. Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) was used to detect and correct for pleiotropy, and Cochran Q assessed heterogeneity. Leave-one-out and Mendelian Randomization-Egger (MR-Egger) regression sensitivity analyses were performed to evaluate robustness. No evidence of a causal effect was found between CD and either AD or FTD in either direction (P&#x2005;>&#x2005;.05). Similarly, genetic liability to AD or FTD did not increase the risk of CD. Sensitivity analyses supported the robustness of the results, showing no pleiotropy or heterogeneity. Our findings suggest that CD is not causally linked to the development of AD or FTD. While shared genetic factors or comorbidities may exist, the association is likely noncausal, and other mechanisms of cognitive decline in CD patients warrant further study.

Humans↗

Potential mitochondria-associated pathogenic genes in sepsis: a multi-omics Mendelian randomization study.

BACKGROUND: Mitochondrial dysfunction has been implicated in the pathophysiology of sepsis. However, human genetic evidence linking mitochondria-related genes to sepsis susceptibility remains limited. This study aimed to identify mitochondria-related genes associated with sepsis risk using a multi-omics Mendelian randomization framework. METHODS: Summary-data-based Mendelian randomization (SMR) was applied using sepsis genome-wide association study (GWAS) summary statistics from the UK Biobank and FinnGen databases. Expression, methylation, single-cell, and protein quantitative trait loci (QTLs) were used as genetic instruments. Colocalization analyses were conducted to evaluate whether SMR associations were driven by shared genetic variants. Expression of prioritized candidate genes was further examined in clinical septic samples, and correlations with disease severity (SOFA scores) were assessed. RESULTS: SMR analysis prioritized 13 mitochondria-related genes associated with sepsis risk. Immune cell-specific eQTL analysis suggested that genetically predicted SURF1 expression in memory B cells and na&#xef;ve T cells was associated with sepsis risk. Differential expression of 12 candidate genes was confirmed in septic patients by qPCR, and PPOX expression showed a negative correlation with SOFA scores. Integration of mQTL and eQTL data supported a regulatory relationship between methylation at cg06661924 and AK4 expression. Increased genetically predicted AK4 expression was associated with higher sepsis risk (OR&#xa0;=&#xa0;1.21, 95% CI 1.02-1.42). Protein-level analysis identified DUT as a potential sepsis-associated candidate, with consistent evidence across streptococcal and pneumococcal septicemia subtypes. Subtype analyses also suggested heterogeneous genetic signals across different sepsis subtypes. CONCLUSION: This study prioritized several mitochondria-related genes associated with sepsis susceptibility based on human genetic evidence. These findings provide candidate targets for further mechanistic and translational investigation.

Humans↗

The causal relationship between antihypertensive drugs and knee osteoarthritis: A drug target Mendelian randomization study.

Recently studies have revealed a robust association between hypertension and knee osteoarthritis (KOA), with patients likely to suffer from both conditions. We employed Mendelian randomization (MR) analysis to assess the impact of antihypertensive medications on KOA, aiming to offer clinical guidance for concomitant drug therapy and identify potential therapeutic targets for KOA. We obtained exposure instruments (instrumental variables) by locating Single-nucleotide polymorphisms related to systolic blood pressure near drug target genes. We then conducted Mendelian randomization analyses between the exposure data and genome-wide association studies data on KOA to evaluate the impact of antihypertensive drugs on KOA. We observed a significant association between decreased expression of the SLC12A2 target gene and a reduced risk of KOA (odds ratio: 0.915, 95% confidence interval: 0.869-0.964, P&#x2005;<&#x2005;.001). In this study, we find that SLC12A2 inhibitors can have a beneficial effect on KOA, and that the SLC12A2 gene may be a potential therapeutic target for KOA. These findings suggest that when treating patients with both hypertension and KOA, clinicians may consider prioritizing the use of SLC12A2 inhibitors.

Humans↗

Mitochondria-Related Pathogenic Genes in Paediatric Asthma: A Multi-Omics Mendelian Randomization Study.

Mitochondrial dysfunction is implicated in asthma pathogenesis, but causal roles of mitochondrial-related genes in paediatric asthma remain unclear. We performed a multi-omics Mendelian randomization study integrating GWAS data from paediatric asthma cohorts with blood-based methylation quantitative trait loci (mQTLs), expression QTLs (eQTLs) and protein QTLs (pQTLs) datasets. Causal inference was assessed using Summary-data-based Mendelian Randomization (SMR) and HEIDI testing, complemented by colocalization analysis. Findings were validated in independent cohorts and evaluated for tissue specificity using GTEx. Functional enrichment and protein-protein interaction (PPI) network analyses were conducted. SMR analysis identified 80 methylation sites spanning 54 genes, 26 gene expressions, and three proteins significantly associated with paediatric asthma. Colocalization analysis confirmed strong evidence for 10 methylation sites (7 genes), the STX17 eQTL (PP.H4&#x2009;=&#x2009;0.98) and the UNG pQTL (PP.H4&#x2009;=&#x2009;0.84). Tissue-specific eQTL validation replicated the STX17 association. Multi-omics integration associated ALAS1 (cg13241645, cg15698299) and TXNRD1 (cg09884423) with asthma at both methylation and expression levels, with colocalization supporting both ALAS1 associations. Furthermore, integrated mQTL-eQTL analysis suggests that DNA methylation potentially regulates ALAS1 and TXNRD1 expression. Functional enrichment and network analyses revealed that these candidate genes converge on mitochondrial metabolic pathways and identified seven hub genes with potential regulatory significance (SDHB, MFN2, GLDC, PHB2, TXNRD1, ATP5MC1 and PHB). This study provides multi-omics evidence supporting a causal role for mitochondrial-related genes, particularly ALAS1 and TXNRD1, in paediatric asthma, offering new insights into pathogenesis and potential therapeutic targets.

Humans↗

Identifying potential drug targets for physical and cognitive frailty: an integrative analysis of CHARLS cohort, mendelian randomization, and gene colocalization.

With the aging of the population, frailty has become a common syndrome that severely affects the quality of life of older adults. This study aims to analyze the correlation between cognition and frailty, physical activity and frailty, and elucidate the potential pharmacological targets of cognitive frailty and physical frailty.We conducted logistic regression analyses using data from the China Health and Retirement Longitudinal Study (CHARLS) to examine the associations between total cognition and frailty, physical activity and frailty. Furthermore, summary-data-based Mendelian randomization (SMR) and two-sample Mendelian randomization (TSMR) were employed to explore potential pharmacological targets for frailty. Genes associated with physical frailty and cognitive frailty were identified, followed by analysis via colocalization analysis, phenome-wide association studies (PheWAS), and DsigDB drug prediction. Cross-sectional analysis of CHARLs revealed that total cognition(OR 0.93, 95% CI 0.92-0.95) and middle physical activity(OR 0.95, 95% CI 0.92-0.97) were negatively correlated with frailty. SMR identified 41 drug genes associated with frailty, and subsequent TSMR validation and co-localization analysis showed that 11 candidate genes exhibited strong colocalization (PP.H4&#x2009;>&#x2009;0.8). GRPEL 1, PABPC 4, and WBP 2NL were ultimately identified as potential drug targets associated with physical frailty, while LANCL1, LRPPRC, FADS1, and WBP2NL were identified as potential drug targets associated with cognitive frailty. Phenome-wide association analysis(PheWAS) did not reveal any significant associations between these genes and other phenotypes at the genome-wide significance threshold. Laudanosine, 25-hydroxycholesterol, and hexadecanal emerged as the top three candidate compounds for therapeutic intervention. We identified potential drug targets for physical frailty and cognitive frailty through comprehensive analysis and elucidated drugs associated with potentially relevant genetic markers, thereby laying the foundation for a deeper understanding of the mechanisms of frailty.

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↗

New insights into causal relationship between serum lipids, obesity, and asthma: a Mendelian randomization study.

OBJECTIVE: To identify causal risk factors for asthma using a Mendelian randomization (MR) approach. METHODS: Genetic variants associated with the exposures at the genome-wide significance level (p&#x2009;<&#x2009;5&#x2009;&#xd7;&#x2009;10&#x2009;-&#x2009;8) were obtained from corresponding genome-wide association studies. Summary-level statistical data for asthma were obtained from the UK Biobank (UKB) and the FinnGen Consortia. Univariate and multivariate MR analyses were performed to clarify causal relationships among obesity, serum lipids, and asthma. Meta-analyses were performed to combine UKB and FinnGen results using a fixed-effects model. RESULTS: In FinnGen, the odds for asthma increased for every 1-SD increase in body mass index (BMI; odds ratio [OR] 1.292, p&#x2009;=&#x2009;1.34&#x2009;&#xd7;&#x2009;10-7), together with body fat percentage (BF%; OR 1.449, p&#x2009;=&#x2009;4.90&#xd7;10-3), and total cholesterol level (OR = 0.949, p&#x2009;=&#x2009;0.027). However, higher BMI and BF% were found to increase the risk for asthma in the multivariate MR analysis. In the UKB, the BMI results were replicated. Meta-analysis revealed that high-density lipoprotein cholesterol could also increase the risk for asthma, although there were no associations with other risk factors included in this study. CONCLUSION: This MR study found that genetically predicted higher BF% and BMI could increase the risk for asthma and corroborated some risk factors for asthma from previous MR studies. Moreover, the results suggest that higher BMI and BF% could serve as independent risk factors for asthma.

Humans↗

Causal relationships between somatic movement, brain structures, and mental well-being: A multi-stage Mendelian randomization study.

BACKGROUND: While the relationships between somatic movement, mental well-being, and brain health have been well established, the causal nature and underlying mechanisms of such associations remain incompletely understood. METHODS: By applying multi-stage Mendelian randomization to multi-source summary data derived from genome-wide association studies, we examined the causal effects of 4 somatic movement measures on 2 mental well-being indices and 13 types of brain structures, followed by testing the mediating roles of brain structures in accounting for the causal associations between somatic movement and mental well-being. RESULTS: Two-sample Mendelian randomization revealed that more physical activity was causally associated with greater mental well-being (life satisfaction and positive affect), while more sedentary behavior (longer leisure screen time and more sedentary behavior at work) with lower mental well-being. With respect to brain structures, sedentary behavior was causally linked to decreased volume, surface area, and local gyrification index in distributed cortical regions. Remarkably, decreased surface area of the piriform cortex was found to mediate the causal associations between sedentary behavior and lower mental well-being. CONCLUSIONS: Our findings not only complement and extend earlier reports on the associations of somatic movement with mental well-being and brain health by further resolving the causality but also help elucidate the neural mechanisms by which sedentary behavior adversely affects mental well-being.

Humans↗

Refining the link between REM sleep behavior disorder and neurodegeneration: Genetic correlation, Mendelian randomization, and colocalization evidence.

Observational studies have proposed a link between isolated rapid eye movement sleep behavior disorder (iRBD) and several neurodegenerative diseases. We employed genome-wide linkage disequilibrium score regression (LDSC), standard two-sample Mendelian randomization (MR), and colocalization analysis to assess the causal links between iRBD and these neurodegenerative conditions. iRBD demonstrated a positive causal association with Alzheimer disease (odds ratio [OR]&#x2005;=&#x2005;1.02, 95% confidence interval [CI]: 1.00-1.03, P&#x2005;=&#x2005;1.10E-02), Parkinson disease (OR&#x2005;=&#x2005;1.10, 95% CI: 1.03-1.16, P&#x2005;=&#x2005;2.96E-03), and multiple sclerosis (OR&#x2005;=&#x2005;1.09, 95% CI: 1.02-1.17, P&#x2005;=&#x2005;1.61E-02). A strong positive genetic correlation with dementia with Lewy bodies was observed (rg&#x2005;=&#x2005;1.6313, P&#x2005;=&#x2005;.0002), along with a causal association (OR&#x2005;=&#x2005;1.45, 95% CI: 1.03-2.06, P&#x2005;=&#x2005;3.53E-02), further supported by colocalization analysis. No significant causal relationship was identified between iRBD and amyotrophic lateral sclerosis (all P&#x2005;>&#x2005;.05). Additionally, reverse Mendelian randomization analyses did not reveal any causal relationships between the neurodegenerative diseases studied and iRBD. Our findings provide robust genetic evidence supporting a causal relationship between iRBD and the risk of multiple neurodegenerative diseases, highlighting the potential for shared pathophysiological mechanisms.

Humans↗

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&#x2005;+&#x2005;T cells), CD25++ CD45RA- CD4 nonregulatory T cells (%T cells), CD25++ CD8&#x2005;+&#x2005;T cells (%T cells), and CD64&#x2005;+&#x2005;CD16&#x2005;+&#x2005;monocytes were 0.925 (95% CI&#x2005;=&#x2005;0.874-0.978, P&#x2005;=&#x2005;6.516&#x2005;&#xd7;&#x2005;10-3), 0.935 (95% CI&#x2005;=&#x2005;0.878-0.995, P&#x2005;=&#x2005;.035), 0.936 (95% CI&#x2005;=&#x2005;0.889-0.985, P&#x2005;=&#x2005;.011), 0.863 (95% CI&#x2005;=&#x2005;0.786-0.948, P&#x2005;=&#x2005;2.142&#x2005;&#xd7;&#x2005;10-3), and 0.636 (95% CI&#x2005;=&#x2005;0.519-0.778, P&#x2005;=&#x2005;1.18&#x2005;&#xd7;&#x2005;10-5), respectively. The mediation analysis indicated that the absolute count of CD25++ CD8&#x2005;+&#x2005;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↗

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]&#x2009;=&#x2009;1.17, 95% confidence interval [CI]&#x2009;=&#x2009;1.09-1.26, p&#x2009;=&#x2009;1.33&#x2009;&#xd7;&#x2009;10-&#x2009;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↗

DNA Methylation, SERPING1 Expression, and Immune-related Traits in Osteoporosis: A Mendelian Randomization Study And Supportive Ex Vivo Evidence.

INTRODUCTION: Osteoporosis (OP) is a major public health burden; however, the role of SERPIN family proteins remains incompletely understood. This study aimed to investigate genetically inferred associations between SERPINs and OP and to explore potential regulatory relationships. METHODS: Genome-wide association study (GWAS) summary statistics were used to perform two-sample Mendelian randomization (MR) and summary-data-based Mendelian randomization (SMR) analyses. Primary MR estimates were derived using inverse-variance-weighted (IVW), MR-Egger, weighted median, simple mode, and weighted mode methods. Cancellous bone tissue from the greater trochanter of the femur was collected from three patients with OP and three non-osteoporotic controls. qPCR and WB were used to analyze the whole bone homogenate, IHC was used to detect decalcified bone sections, and mediation analysis was used to explore potential regulatory associations. RESULTS: Among the proteins of the SERPIN family, only SERPING1 had an obvious positive correlation with the risk of osteoporosis (OR = 1.06, P = 0.0012). qPCR, WB, and IHC analyses demonstrated increased SERPING1 mRNA and protein expression in bone tissue from OP patients. Mediation analyses suggested that cg15918732 DNA methylation may serve as an upstream regulatory factor for SERPING1 expression. In addition, the downstream associations also consist of the alteration of immune cell conditions, like the decrease in the quantity of natural killer cells and T cells, and the rise in the level of mononuclear cells, and so forth. DISCUSSION: These findings provide genetic evidence for the possible role of SERPING1 in OP, which may be achieved through epigenetic regulation and immune pathways. Due to the corresponding characteristics of genetic inference and the small sample size, these results are hypothetical and generative. CONCLUSION: This study shows that DNA methylation of cg15918732 may be associated with SERPING1 expression in osteoporosis and immune-related traits. These findings provide new insights into potential epigenetic and immunological pathways in osteoporosis, which may contribute to future mechanistic and translational research.

Humans↗

Mitochondrial dysfunction in the pathogenesis of intervertebral disc herniation: a mitochondrial related genome-wide Mendelian randomization analysis.

BACKGROUND: As a degenerative disease, the pathophysiology of intervertebral disc herniation (IDH) closely related to mitochondrial dysfunction. However, the specific molecular mechanisms involved have yet to be precisely established. METHODS: Here, we employed a two-sample, two-step Mendelian Randomization (MR) approach, along with summary-Data-Based MR, genetic colocalization, full phenomenon association analysis, and GO and KEGG enrichment analysis to investigate the genetical effects of mitochondrial dysfunction on IDH. RESULTS: From the intercross between mitochondrial-related genes and eQTLGen genes, we obtained seven genes (DMPK, EHHADH, SLC25A16, ME3, METTL17, TUFM, NDUFA13) with strong causal association with disc herniation. By SMR and genetic colocalization analysis, we further identify five key genes (EHHADH, METTL17, TUFM, NDUFA13, DMPK) as the direct causal tartgeted genes with no heterogeneity and pleiotropy in the SNPs of the genes. Full phenomenon Mendelian randomization was performed to determine possible side effects of the 5 targeting genes. Finally, we validated the expressions of key genes in the degenerative intervertebral discs tissues by qRT-PCR and double-immunofluorescence examinations, and the results were consistent with the MR analysis. CONCLUSIONS: Our study provided genetic support for the relationship between mitochondrial related genes and IDH, implicating potential therapeutic targets for future development. However, more basic experiments need to be finished to validate the role of key genes in the development of IDH.

Intervertebral Disc Displacement↗