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Genetic interconnections between personality-related phenotypes and psychiatric disorders.

BACKGROUND: Personality-related phenotypes are genetically correlated with psychiatric disorders, but whether these relationships reflect shared genetic loci and differ across individual phenotypes remains unclear. We investigated their shared genetic architecture at the level of specific phenotype-disorder pairs. METHODS: We analyzed genome-wide association study summary statistics for 13 personality-related phenotypes and eight psychiatric disorders in populations of European ancestry. Genetic correlations were evaluated separately for 104 phenotype-disorder pairs using linkage disequilibrium score regression and high-definition likelihood. For pairs supported by both methods, MTAG and CPASSOC were applied separately to identify pleiotropic signals, followed by linkage disequilibrium clumping, Bayesian colocalization, gene prioritization, functional enrichment and bidirectional two-sample Mendelian randomization analyses. No composite personality or psychiatric-disorder phenotype was constructed. RESULTS: Among the 104 evaluated pairs, 77 showed significant positive genetic correlations in both analyses. Joint screening of MTAG and CPASSOC results identified pleiotropic signals in 61 pairs, comprising 1088 independent lead SNV-pair associations and 776 unique SNVs. Bayesian colocalization supported 351 signals across 42 pairs and 284 unique lead SNVs. MAGMA identified 1293 unique genes, of which 379 were prioritized by PoPS and 151 were further supported by SMR. These genes were enriched in brain tissues and biological processes involving nervous system development, synaptic organization and intercellular connectivity. Inverse-variance weighted Mendelian randomization identified 41 forward and 32 reverse associations after false-discovery-rate correction, including 21 pairs with bidirectional evidence. CONCLUSION: These item-resolved analyses identify widespread but heterogeneous genetic sharing between personality-related phenotypes and psychiatric disorders. The findings provide a pair-specific map of shared loci and prioritized genes, while the Mendelian randomization results should be interpreted cautiously because of residual heterogeneity and potential horizontal pleiotropy. Further validation in diverse populations and functional studies is required.

Colocalization↗

Accelerated Biological Aging Increases the Risk of Head and Neck Cancer: Insights From Genetic Instruments of Epigenetic Clocks.

Epigenetic clocks are robust biomarkers of biological aging and have been associated with cancer susceptibility. However, the relationship between genetically predicted epigenetic age acceleration and head and neck cancer risk remains unclear. Using a large case-control study of 2189 head and neck squamous cell carcinoma (HNSCC) cases and 2189 age- and sex-matched controls, we investigated the associations between polygenic scores (PGSs) for multiple epigenetic clocks and HNSCC risk, and evaluated their potential causal roles using two-sample Mendelian randomization (MR). Genome-wide association study (GWAS)-identified single nucleotide polymorphisms (SNPs) associated with four epigenetic clocks (HannumAge, HorvathAge, GrimAge, and PhenoAge) were used to construct clock-specific PGSs. Logistic regression models were applied to assess associations between PGSs and HNSCC risk, while MR analyses, including inverse-variance weighted (IVW), weighted median, and MR-Egger methods, were used to infer potential causal relationships. Among the 48 epigenetic clock-associated SNPs, 12 showed nominal associations with HNSCC risk, and one variant (rs2275558 in PBX1) remained significant after Bonferroni correction (OR = 0.67, 95% CI: 0.60-0.76). PGSs for all four epigenetic clocks were higher in cases than in controls. In logistic regression analyses, each standard deviation increase in HannumAge PGS was associated with a 25% higher risk of HNSCC (OR = 1.25, 95% CI: 1.10-1.41), whereas HorvathAge, GrimAge, and PhenoAge PGSs showed weaker positive associations (ORs ranging from 1.06 to 1.10). Individuals in the highest PGS quartile for all four epigenetic clocks exhibiting 14%-25% higher risk than those in the lower three quartiles. MR analyses supported potential causal effects of genetically predicted HannumAge (IVW OR = 1.24 per SD increase, 95% CI: 1.09-1.42) and GrimAge (IVW OR = 1.23 per SD increase, 95% CI: 0.98-1.56) on HNSCC risk, with consistent estimates in weighted median analyses. Our results highlight biological aging as a potential etiologic mechanism for HNSCC and suggest that epigenetic clock-related genetic profiles may improve HNSCC risk stratification.

Humans↗

Genetic Basis of Pancreatic Steatosis: A Systematic Review of Comparison between African and Non-African Populations.

This systematic review compared genetic evidence of pancreatic steatosis across African and non-African populations to illuminate ancestry-specific mechanisms and precision-prevention opportunities. Following PRISMA guidelines for reporting, a search was conducted across PubMed, Scopus, Web of Science, and NHGRI-EBI GWAS Catalog for studies spanning 2011 to 31st March 2026. Eligible studies included genome-wide association studies (GWAS), polygenic risk score (PRS), and Mendelian randomization (MR) analyses that reported genetic associations with pancreatic fat phenotypes and had explicit ancestry stratification or comparison. Narrative thematic synthesis was performed due to methodological heterogeneity. Six core genetic studies (N > 120,000 participants) were included. The only multi-ethnic GWAS found a strong protective variant of African ancestry, rs73449607 (near PDX1/PLUTO), which reduced pancreatic fat (&#x3b2; = -0.67, P = 4.50 &#xd7; 10&#x207b;&#x2078;) and explained 14.3% of the variance in African Americans (versus 5.3% overall). UK Biobank race-stratified PRS analyses confirmed the lowest pancreatic fat fraction in Black participants, with the strongest HbA1c PRS-fat association in this group (&#x3c1; = 0.23, P < 0.0001). European-dominant GWAS highlighted risk loci, including FUT2 rs601338 (higher fat and chronic pancreatitis risk, OR 1.26). MR studies demonstrated causal links between genetically predicted intra-pancreatic fat deposition (IPFD) and pancreatic ductal adenocarcinoma (PDAC) (OR 2.46 per SD) but not diabetes. African-ancestry genomes confer substantial protection against pancreatic steatosis, whereas non-African genomes are enriched for risk alleles that amplify the non-alcoholic fatty pancreas disease (NAFPD)-to-PDAC cascade. These ancestry-differentiated mechanisms position NAFPD as a precision medicine target.

Africa↗

[Integration of genetic factors into epidemiological studies].

During the last two decades, genetic epidemiology has been established in parallel to the area of classical epidemiology. This paper presents some essentials of the epidemiology of genetic factors. It begins with a discussion of complex diseases that are characterized by an involvement of several genes. The problems that are attached to modeling gene-gene and gene-environment interactions and their integration into causal pathways are elucidated and the role of genetic factors in the etiology of complex diseases is investigated. Classical and new epidemiological study designs that allow an integration of genetic data are introduced. The introduction of this data is partly motivated by the danger of bias due to genetic heterogeneity (population stratification) in classical designs. The problem of replication of study results is discussed and the concept of Mendelian randomization is presented.

Case-Control Studies↗

Association of gestational diabetes with other lactation-related disorders: A 2-sample Mendelian randomization analysis of causal effects.

Gestational diabetes mellitus (GDM) is associated with adverse metabolic outcomes and may also be related to postpartum breast and lactation disorders. Observational studies are susceptible to confounding and reverse causation. We used a 2-sample Mendelian randomization design to examine the association between genetic liability to GDM and other disorders of the breast and lactation associated with childbirth. Genetic liability to GDM was associated with higher odds of a composite phenotype of breast and lactation disorders associated with childbirth. Replication using independent samples and more specific clinical outcomes is required. Summary statistics for GDM and the FinnGen outcome "other disorders of breast and lactation associated with childbirth" were obtained from the Integrative Epidemiology Unit open genome-wide association study resource. single nucleotide polymorphisms associated with GDM (P&#x2005;<&#x2005;5&#x2009;&#xd7;&#x2009;10-6) were clumped (R2&#x2005;<&#x2005;0.001) within 10,000&#x2009;kb. The inverse-variance weighted method was the primary analysis; Mendelian randomization-Egger, weighted median, simple mode, and weighted mode analyses were complementary methods. Heterogeneity, directional horizontal pleiotropy, leave-one-out, and Steiger directionality analyses were performed. Nineteen single nucleotide polymorphisms were retained; F statistics ranged from 21.08 to 288.04. Genetic liability to GDM was associated with higher odds of the outcome in the inverse-variance weighted analysis (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.08-2.09; P&#x2005;=&#x2005;.0165). The weighted median (OR, 1.76; 95% CI, 1.09-2.84; P&#x2005;=&#x2005;.0216) and weighted mode estimates (OR, 1.98; 95% CI, 1.21-3.26; P&#x2005;=&#x2005;.0148) were directionally consistent. There was no statistical evidence of heterogeneity or directional horizontal pleiotropy. The Steiger test supported the direction from GDM to the outcome (P&#x2005;=&#x2005;1.30&#x2005;&#xd7;&#x2005;10-11).

Diabetes, Gestational↗

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↗

Circulating inflammatory proteins and osteomyelitis: A bidirectional Mendelian randomization and colocalization analysis.

Circulating inflammatory proteins (CIPs) have been implicated in the progression of osteomyelitis (OM); however, whether these proteins play a causal role or are merely a consequence remains unclear. This study aimed to assess the causal relationships between CIPs and OM using a bidirectional 2-sample Mendelian randomization (MR) approach. MR analyses were performed using genome-wide association study summary statistics for 91 inflammation-related proteins (n&#x2005;=&#x2005;14,824) and OM (1881 cases and 3,91,037 controls). The inverse variance weighted method was used as the primary analytical approach, supplemented by MR-Egger, weighted median, simple mode, and weighted mode methods. Sensitivity analyses were conducted to evaluate heterogeneity, horizontal pleiotropy, and robustness. Colocalization analysis was applied to identify shared causal variants, and pathway enrichment analysis was used to explore underlying biological mechanisms. Forward MR analysis revealed that elevated levels of tumor necrosis factor-beta (TNF-&#x3b2;) were significantly associated with increased OM risk (odds ratio [OR]&#x2005;=&#x2005;1.132; 95% confidence interval [CI]: 1.052-1.217; false discovery rate [FDR]&#x2005;=&#x2005;0.027). Conversely, decreased levels of osteoprotegerin (OR&#x2005;=&#x2005;0.772; 95% CI: 0.671-0.889; FDR&#x2005;=&#x2005;0.015) and adenosine deaminase (OR&#x2005;=&#x2005;0.811; 95% CI: 0.736-0.894; FDR&#x2005;<&#x2005;0.001) were associated with increased OM risk. Reverse MR analysis identified increased levels of interleukin-15 receptor alpha, C-X-C motif chemokine ligand 1, fms-related tyrosine kinase 3 ligand, interleukin-20, interleukin-10 (IL10), C-C motif chemokine ligand 19, and CXCL6 as being significantly associated with OM susceptibility (all FDR&#x2005;<&#x2005;0.05). Colocalization analysis provided strong evidence for a shared causal variant between TNF-&#x3b2; and OM (posterior probability for hypothesis 4&#x2005;=&#x2005;0.999). Enrichment analyses indicated involvement of implicated proteins in Toll-like receptor signaling and T-helper 17 cell differentiation pathways. This study identified several CIPs - including TNF-&#x3b2;, osteoprotegerin, and adenosine deaminase - as potentially causal in OM development. These findings highlight promising targets for future immunomodulatory therapies aimed at preventing or mitigating osteomyelitis.

Humans↗

Plasmacytoid dendritic cell-mediated L-glutamate catabolism links gut microbiota to male infertility.

Emerging evidence suggests that gut microbiota composition influences male reproductive health; however, the immunometabolic mechanisms underlying this association remain insufficiently characterized. We investigated whether specific immune cell-mediated metabolic pathways, particularly plasmacytoid dendritic cell (pDC)-driven L-glutamate catabolism via the hydroxyglutarate pathway, contribute to the causal link between gut microbiota and male infertility. We conducted a 2-sample, 2-step Mendelian randomization (MR) analysis using inverse-variance weighting as the primary estimator and Bayesian weighted MR for robustness. Exposure data comprised 412 gut microbial taxa/metabolic pathways and 731 immune cell phenotypes from large European-ancestry genome-wide association studies. Male infertility genome-wide association studies data (1429 cases; 128,710 controls) were obtained from FinnGen R10. Only exposure-mediator-outcome pairs meeting stringent pleiotropy, heterogeneity, and reverse-causality criteria were retained for mediation analysis. Nine microbial taxa/metabolic pathways and 18 immune traits exhibited putative causal associations with male infertility. The L-glutamate degradation V pathway via hydroxyglutarate was linked to reduced infertility risk (inverse-variance weighting odds ratio [OR]&#x2005;=&#x2005;0.68; 95% confidence interval, 0.52-0.89; P&#x2005;=&#x2005;.005). Two-step MR suggested that forward scatter area on pDCs may mediate this association, although the mediation effect was imprecise (effect&#x2005;=&#x2005;0.0277; 95% confidence interval, -0.0348 to 0.0903). This study provides suggestive genetic evidence that pDC-mediated glutamate catabolism may connect gut microbial metabolic activity to male infertility. These findings highlight immunometabolic pathways as testable targets for mechanistic validation and microbiota-directed interventions.

Male↗

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&#x2005;=&#x2005;.04; IL-13: OR: 1.09, 95% CI: 1.01-1.18, P&#x2005;=&#x2005;.023), while CXCL10 was suggestively linked to a lower risk of IBD (CXCL10: OR: 0.90, 95% CI: 0.82-0.99, P&#x2005;=&#x2005;.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&#x2005;=&#x2005;.023; CCL3: OR: 1.22, 95% CI: 1.03-1.45, P&#x2005;=&#x2005;.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↗

Bioavailable testosterone reduces the risk of lung squamous cell carcinoma: a comprehensive data study.

BACKGROUND: The association between testosterone and lung cancer remains unclear. This study investigates the relationship between testosterone levels and lung cancer risk, focusing on bioavailable testosterone levels (BTLs), total testosterone levels (TTLs), and sex hormone-binding globulin (SHBG) in relation to lung cancer subtypes. METHODS: We utilized bidirectional and multivariable Mendelian randomization (MR) analyses based on genome-wide association studies (GWAS) to assess causal links. To validate the findings clinically, immunohistochemical (IHC) staining for androgen receptor (AR) expression and survival analyses were conducted on a cohort of 90 patients with lung squamous cell carcinoma (LUSC). RESULTS: MR analysis demonstrated that higher BTLs were significantly associated with a reduced risk of LUSC (OR&#x2009;=&#x2009;0.365, P&#x2009;=&#x2009;0.001), while no significant associations were observed for TTLs or SHBG. Reverse MR analysis found no causal effect of lung cancer on testosterone levels. Multivariable MR confirmed BTLs as an independent protective factor. In the clinical cohort, AR expression was significantly associated with better prognosis, showing improved median progression-free survival (12.3 vs. 9.0 months, P&#x2009;=&#x2009;0.01) and median overall survival (35.3 vs. 29.4 months, P&#x2009;<&#x2009;0.01). Cox regression identified AR expression as an independent protective factor for patient outcomes. However, study limitations include potential residual confounding, ethnic heterogeneity between European GWAS data and Asian clinical cohorts, and the lack of direct experimental validation. CONCLUSIONS: Our findings suggest that higher BTLs may play a protective role against LUSC. BTLs and AR expression show potential as valuable biomarkers for the diagnosis and prognostic assessment of LUSC.

Humans↗

Bayesian Mendelian randomization reveals a protective effect of later age at first sexual intercourse against erectile dysfunction.

Erectile dysfunction (ED) is a prevalent health condition with significant psychosocial impacts, yet the causal role of age at first sexual intercourse (AFS) remains unclear. This study investigated the causal effect of AFS on the risk of ED using Mendelian randomization (MR) and Bayesian methods. Five traditional 2-sample MR analyses and 5 Bayesian MR analyses were performed using genome-wide association studies summary statistics from European populations. Sensitivity analyses included MR Egger regression, MR-pleiotropy residual sum and outlier, and Cochran Q-test. In mixed-sex cohorts (Groups 1 and 2), inverse variance weighted results demonstrated significant protective effects: odds ratio (OR)&#x2005;=&#x2005;0.626, &#x3b8;&#x2005;=&#x2005;-0.469, P&#x2005;=&#x2005;2.73&#x2005;&#xd7;&#x2005;10-6 for Group 1 and OR&#x2005;=&#x2005;0.617, &#x3b8;&#x2005;=&#x2005;-0.483, P&#x2005;=&#x2005;3.56&#x2005;&#xd7;&#x2005;10-5 for Group 2. The analyses for male-specific cohorts (Groups 3-10) showed weaker but consistent effects. For Group 3, OR&#x2005;=&#x2005;0.643, &#x3b8;&#x2005;=&#x2005;-0.442, P&#x2005;=&#x2005;.010. For Group 4, some instrumental variables associated with confounders were removed. The result became statistically insignificant: OR&#x2005;=&#x2005;0.680, &#x3b8;&#x2005;=&#x2005;-0.385, P&#x2005;=&#x2005;.064. For Group 5, the instrument selection criteria were relaxed and significance was retained: OR&#x2005;=&#x2005;0.695, &#x3b8;&#x2005;=&#x2005;-0.364, P&#x2005;=&#x2005;.016. For Groups 6 to 10, Bayesian MR was used to strengthen the inferences. In particular, for Group 8, which has a strongly informed prior, a posterior mean &#x3b8;&#x2005;=&#x2005;-0.358 and a 95% credible interval (-0.575, -0.136) were obtained. This study provides evidence supporting a causal protective effect of later AFS on ED risk. While traditional MR analyses in male-specific cohorts yielded suggestive results, Bayesian MR analyses, which allow for the integration of prior evidence, provided more precise estimates and strengthened the causal inference. These findings may inform future sexual health policies. Strengths include the use of male-specific cohorts and Bayesian enhancement for weak instruments. Limitations include reliance on European-ancestry data and inability to stratify ED subtypes.

Male↗

Genetic predisposition and mediating pathways in ischemic stroke-induced cardiac arrhythmias: a genome-wide analysis.

INTRODUCTION: The clinical presentation of stroke-heart syndrome (SHS) underscores the interplay between the central nervous system and the cardiovascular system. While cardiac arrhythmia is the prevalent form of cardiac injury in SHS patients, the causal link between ischemic stroke and cardiac arrhythmia is still unclear. METHODS: Mendelian randomization analyses and genome-wide association studies data were used to investigate the causal role of ischemic stroke on cardiac complications. Mediation and colocalization analyses were used to identify potential pathways and shared genetic variants. Single nucleotide polymorphisms (SNPs) associated with arrhythmias and ischemic stroke were used for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Gene expression omnibus (GEO) database from atrial fibrillation patients were used for validation. RESULTS: Mendelian randomization analyses showed a strong correlation between arrhythmias, including ventricular tachyarrhythmias and atrial fibrillation, with ischemic stroke. Diabetic microvascular (nephropathy, retinopathy) and macrovascular (cardiomyopathy, peripheral arterial disease) complications significantly mediated the effect of ischemic stroke on cardiac arrhythmias and atrial fibrillation, explaining 28.69&#xa0;% and 20.48&#xa0;% of the indirect effect, respectively. Colocalization analyses identified a shared causal variant in the Phosphodiesterase 3A (PDE3A) gene (rs11045239), providing genetic evidence for a shared pathogenic pathway between ischemic stroke and cardiac arrhythmias. Moreover, KEGG pathway enrichment analyses identified a role of the cyclic adenosine monophosphate (cAMP) signaling pathway in both ischemic stroke and arrhythmias. Validation using the GEO database confirmed a significant upregulation of the PDE3A gene expression in atrial fibrillation patients. CONCLUSION: This study demonstrated a causal link between ischemic stroke and cardiac arrhythmias, with diabetic complications as one mediating factor. The identification of a shared causal variant in the PDE3A gene and the role of the cAMP signaling pathway have the potential to improve prediction and management of SHS patients.

Humans↗

Maternal COVID-19 infection associated with offspring neurodevelopmental disorders.

Maternal COVID-19 infection increases the incidence of neurodevelopmental disorders (NDDs) in offspring, although the underlying mechanisms have not been elucidated. This study demonstrated that COVID-19 infection during pregnancy disrupted the balance of maternal and fetal immune environments, driving alterations in astrocytes, endothelial cells, and excitatory neurons. A risk score was established using 47 unique genes in the single-cell transcriptome of gestational mothers. The high risk score in CD4 proliferating T cell level served as an indicator for increased risk of offspring NDDs. Summary-based Mendelian randomization and phenome-wide association study analyses were conducted to identify the causal association of the transcriptional changes with the increased risk of offspring NDDs. Additionally, 10 drugs were identified as potential therapeutic candidates. Our findings support a model where the maternal COVID-19 infection changed the levels of CD4 proliferating T cells, leading to the alterations of astrocytes, endothelial cells, and excitatory neurons in offspring, contributing to the increased risk of NDDs in these individuals.

Humans↗

Integrative Analysis Uncover the Effects and Multi-Omics Features of Thigh Muscle Fat Infiltration.

The health impacts and underlying biological pathways of thigh muscle fat infiltration (TMFI) remain incompletely understood. In this study, we analyzed TMFI measured by magnetic resonance imaging in 55,120 UK Biobank participants and found that higher TMFI was significantly associated with all-cause mortality as well as with all major system-specific diseases examined (p values ranged from 2.50&#x2009;&#xd7;&#x2009;10-88 to 9.97&#x2009;&#xd7;&#x2009;10-04). TMFI also mediated the effects of lifestyle factors on health-related outcomes, with mediation proportions ranging from 6.7% to 71.7%. A genome-wide association study (GWAS) identified 79 lead single nucleotide polymorphisms (SNPs) linked to TMFI, and the polygenic risk score for TMFI was significantly associated with mortality and all incident diseases across examined organ systems in an independent subset of UK Biobank participants of European ancestry who were not included in the TMFI GWAS (n&#x2009;=&#x2009;362,286, all p&#x2009;<&#x2009;0.05). Gene-drug interactions identified multiple drugs that could potentially modulate TMFI. Analysis of single-cell transcriptomic data indicated that myogenic cells were strongly linked to TMFI (p&#x2009;=&#x2009;7.08&#x2009;&#xd7;&#x2009;10-08). Summary-data-based Mendelian randomization and Transcriptome-Wide Association Study analyses revealed numerous genes whose expression in specific tissues was associated with TMFI. Proteomic and metabolomic profiling uncovered a broad array of circulating biomarkers associated with TMFI, many of which mediated the effects of modifiable factors and genetic risk on TMFI. Overall, our results highlight the biological relevance of TMFI to human health and provide insights into the multi-omics mechanisms underlying TMFI, identifying potential targets for interventions.

Humans↗

Post-genome-wide association study dissects genetic vulnerability and risk gene expression of Sj&#xf6;gren's disease for cardiovascular disease.

OBJECTIVES: This study aims to clarify the genetic associations between Sj&#xf6;gren's Disease (SD) and cardiovascular disease (CVD) outcomes, and to conduct an in-depth exploration of specific pleiotropic susceptibility genes. METHODS: We performed two-sample and multivariable Mendelian randomization (MR) analysis to investigate the association between SD and the risk of ischemic heart disease (IHD) and stroke. Linkage disequilibrium score regression (LDSC) and Bayesian co-localization analyses were employed to assess the genetic associations between traits. Cross-phenotype analyses were employed to identify shared variants and genes, followed by a Transcriptome-Wide Association Study (TWAS) and Multi-marker Analysis of Genomic Annotation (MAGMA) based on Multi-Trait Analysis of GWAS (MTAG) results. To validate the pleiotropic genes, we further analyzed tissue-specific differentially expressed genes (DEGs) related to SD using RNA sequencing data. RESULTS: The two-sample and multivariable MR analyses revealed that SD confers a genetic vulnerability to IHD and stroke. LDSC and co-localization analyses indicated a strong genetic linkage between SD and CVDs. Cross-phenotype analyses identified 38 and 37 pleiotropic single nucleotide polymorphisms (SNPs) for SD-Stroke and SD-IHD, respectively, primarily located within the MHC class region on 6p21.32:33 loci. Additionally, TWAS and MAGMA analyses identified pleiotropic genes located outside the MHC regions-seven associated with stroke (UHRF1BP1, SNRPC, BLK, FAM167A, ARHGAP27, C8orf12, and PLEKHM1) and two associated with IHD (UHRF1BP1 and SNRPC). Proxy variants within these genes in SD suggested an increased causal risk for stroke or IHD. Co-localization analysis further reinforced that SD and stroke share significant SNPs within the loci of FAM167A, BLK, C8orf12, SNRPC, and UHRF1BP1. DEG analysis revealed a significant up-regulation of the identified genes in SD-specific tissues. CONCLUSIONS: SD appears genetically predisposed to an increased risk of CVDs. Moreover, this research not only identified pleiotropic genes shared between SD and CVDs, but also, for the first time, detected key gene expressions that elevate CVD risk in SD patients-findings that may offer promising therapeutic targets for patient management.

Humans↗

Exploring the shared genetic basis of attention-deficit/hyperactivity disorder and obstructive sleep apnea: A multi-omics analysis.

BACKGROUND: Observational studies have suggested an association between attention-deficit/hyperactivity disorder (ADHD) and obstructive sleep apnea (OSA), but these findings are often inconsistent due to potential biases from medication use, and varying diagnostic criteria. Genetic analyses can help mitigate these confounding factors, providing additional evidence. METHODS: This study evaluated the genetic correlations between ADHD and OSA using Genome-wide association study (GWAS) summary data, applying linkage disequilibrium score regression (LDSC) and SUPER GeNetic cOVariance Analyzer (SUPERGNOVA). Cross-trait association and colocalization analysis identify potential pleiotropic loci. Tissue enrichment analysis and gene-level analysis of shared genes between OSA and ADHD was conducted. Additionally, bidirectional Mendelian randomization was used to assess potential causal relationships. RESULTS: We found significant genetic correlations between ADHD and OSA (rg&#xa0;=&#xa0;0.309, p&#xa0;=&#xa0;3.252E-27), and identified 8 novel pleiotropic loci through cross-trait association analysis. Tissue enrichment analysis showed that these shared genes were primarily concentrated in brain tissues, particularly in deep gray matter regions, and were associated with immune and inflammatory pathways. Forward Mendelian Randomization analysis showed that ADHD was significantly associated with the risk of OSA (OR 1.070, 95&#xa0;% CI 1.013-1.130, p&#xa0;=&#xa0;0.016), and reverse analysis showed that OSA was significantly associated with the risk of ADHD (OR 1.240, 95&#xa0;% CI 1.106-1.390, p&#xa0;=&#xa0;2.213E-4). CONCLUSION: The findings of this study show a significant positive genetic correlation between ADHD and OSA and each is a risk factor for the other. Inflammation in specific brain regions may be the underlying mechanism for their comorbidity.

Humans↗

Association Between Ticagrelor and Glucose Homeostasis Regulation: Insights from Genetic and Transcriptomic Analyses.

Emerging evidence has demonstrated the additional therapeutic benefits of ticagrelor in acute coronary syndrome (ACS) patients with diabetes. However, the underlying mechanisms of this association remain elusive. Mendelian randomization (MR) analysis using genome-wide association study (GWAS) data on ticagrelor, plasma proteomics and type 2 diabetes was employed to identify causal mediator proteins. RNA sequencing (RNA-seq) of ticagrelor-treated HepG2 cells revealed the molecular pathways regulating glucose metabolism. Genetically proxied ticagrelor was significantly associated with a reduced risk of diabetes (OR&#x2009;=&#x2009;0.859, 95% CI: 0.783-0.934, P&#x2009;=&#x2009;7.98E-05), and 24.41% of this effect was mediated by upregulation of BDH2 protein. In vitro experiments confirmed the enhanced effect of ticagrelor on glucose consumption. Transcriptome analysis revealed that mitochondrial respiratory chain transfer and oxidative phosphorylation (OXPHOS) were significantly enriched, and genes related to ATP biosynthesis were significantly upregulated. These findings highlight the non-platelet function of ticagrelor in maintaining glucose homeostasis, providing insights into potential drug repurposing in the future.

Humans↗

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&#x2005;=&#x2005;.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&#x2005;=&#x2005;.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↗