Genetic Risk Factors Research Articles

Polygenic Interactions With Environmental Exposures in Blood Pressure Regulation: The HUNT Study.

The essential hypertension phenotype results from an interplay between genetic and environmental factors. The influence of lifestyle exposures such as excess adiposity, alcohol consumption, tobacco use, diet, and activity patterns on blood pressure (BP) is well established. Additionally, polygenic risk scores for BP traits are associated with clinically significant phenotypic variation. However, interactions between genetic and environmental risk factors in hypertension morbidity and mortality are poorly characterized. We used genotype and phenotype data from up to 49 234 participants from the HUNT (Trøndelag Health Study) to model gene-environment interactions between genome-wide polygenic risk scores for systolic BP and diastolic BP and 125 environmental exposures. Among the 125 environmental exposures assessed, 108 and 100 were independently associated with SBP and DBP, respectively. Of these, 12 interactions were identified for genome-wide PRSs for systolic BP and 4 for genome-wide polygenic risk scores for diastolic BP, 2 of which were overlapping (P < 2 × 10-4). We found evidence for gene-dependent influence of lifestyle factors such as cardiorespiratory fitness, dietary patterns, and tobacco exposure, as well as biomarkers such as serum cholesterol, creatinine, and alkaline phosphatase on BP. Individuals that are genetically susceptible to high BP may be more vulnerable to common acquired risk factors for hypertension, but these effects appear to be modifiable. The gene-dependent influence of several common acquired risk factors indicates the potential of genetic data combined with lifestyle assessments in risk stratification, and gene-environment-informed risk modeling in the prevention and management of hypertension.

A cell-autonomous role for border-associated macrophages in ApoE4 neurovascular dysfunction and susceptibility to white matter injury.

Apolipoprotein E4 (ApoE4), the strongest genetic risk factor for sporadic Alzheimer's disease, is also a risk factor for microvascular pathologies leading to cognitive impairment, particularly subcortical white matter injury. These effects have been attributed to alterations in the regulation of the brain blood supply, but the cellular source of ApoE4 and the underlying mechanisms remain unclear. In mice expressing human ApoE3 or ApoE4, we report that border-associated macrophages (BAMs), myeloid cells closely apposed to neocortical microvessels, are both sources and effectors of ApoE4 mediating the neurovascular dysfunction through reactive oxygen species. ApoE4 in BAMs is solely responsible for the increased susceptibility to oligemic white matter damage in ApoE4 mice and is sufficient to enhance damage in ApoE3 mice. The data unveil a new aspect of BAM pathobiology and highlight a previously unrecognized cell-autonomous role of BAM in the neurovascular dysfunction of ApoE4 with potential therapeutic implications.

Advancements in Understanding and Managing Radiation Cystitis: A Comprehensive Review.

This manuscript aims to provide a comprehensive overview of the pathophysiology, risk factors, prevention strategies, and management options for radiation cystitis. Recent studies have shed light on the pathophysiology of radiation cystitis, highlighting the role of inflammation, fibrosis, and vascular damage. Emerging preventive measures like stem cell therapy offer promise, alongside novel treatments such as amniotic bladder therapy and hyperbaric oxygen therapy. This review outlines the latest research on radiation cystitis, covering its pathophysiology, risk factors, prevention, and management. Major findings include insights into the mechanisms of RC development, promising preventive and therapeutic approaches, and the importance of standardized treatment pathways. Future research should focus on identifying genetic risk factors, improving treatment efficacy, and enhancing patient outcomes. This review offers valuable insights for clinicians and researchers, guiding future investigations into radiation cystitis management.

Analysis of Genetic Risk Factors Associated with Charcot Foot Based on the FinnGen Study R9 Data: A Wide-angle Mendelian Randomization Study.

Charcot foot or Charcot neuropathic joint disease (CN) is a rare and complex foot disease with unknown pathogenesis, hindering early identification and intervention. The study aimed to clarify the causal association between all predominant risk factors and CN. Two-sample Mendelian Randomization (MR), Multivariate MR, and Bidirectional MR analyses investigated the causal association between 36 modifiable risk factors and CN. The causal relationship between CN and Inflammatory cytokine and immune cells was also analyzed. Genetic factors associated with obesity and genetic susceptibility to various autoimmune diseases and non-cancerous thyroid diseases increased the risk of CN (P < .05), genetically associated high basal metabolic rate and high total cholesterol decreased the risk of CN (P < .05). In addition, we found a bi-directional causal relationship between CN and diabetes. In further immune cell analysis, we found 8 CN related immune cells, and in inflammatory cytokine analysis, we found 2 CN related inflammatory cytokines. This comprehensive MR Study supports the causal role of Obesity-related factors, diabetes, autoimmune-related factors, and smoking in the development and progression of CN. This study identifies a potential cause of CN that has not been identified in previous studies and provides a new direction for further research.

Schizophrenia is associated with altered DNA methylation variance.

Varying combinations of genetic and environmental risk factors are thought to underpin phenotypic heterogeneity between individuals in psychiatric conditions such as schizophrenia. While epigenome-wide association studies in schizophrenia have identified extensive alteration of mean DNA methylation levels, less is known about the location and impact of DNA methylation variance, which could contribute to phenotypic and treatment response heterogeneity. To explore this question, we conducted the largest meta-analysis of blood DNA methylation variance in schizophrenia to date, leveraging three cohorts comprising 1036 individuals with schizophrenia and 954 non-psychiatric controls. Surprisingly, only a small proportion (0.1%) of the 213 variably methylated positions (VMPs) associated with schizophrenia (Benjamini-Hochberg FDR < 0.05) were shared with differentially methylated positions (DMPs; sites with mean changes between cases and controls). These blood-derived VMPs were found to be overrepresented in genes previously associated with schizophrenia and amongst brain-enriched genes, with evidence of concordant changes at VMPs in the cerebellum, hippocampus, prefrontal cortex, or striatum. Epigenetic covariance was also observed with respect to clinically significant metrics including age of onset, cognitive deficits, and symptom severity. We also uncovered a significant VMP in individuals with first-episode psychosis (n = 644) from additional cohorts and a non-psychiatric comparison group (n = 633). Collectively, these findings suggest schizophrenia is associated with significant changes in DNA methylation variance, which may contribute to individual-to-individual heterogeneity.

Midnolin, a Genetic Risk Factor for Parkinson's Disease, Promotes Neurite Outgrowth Accompanied by Early Growth Response 1 Activation in PC12 Cells.

Parkinson's disease (PD) is an age-related progressive neurodegenerative disease. Previously, we identified midnolin (MIDN) as a genetic risk factor for PD. Although MIDN copy number loss increases the risk of PD, the molecular function of MIDN remains unclear. To investigate the role of MIDN in PD, we established monoclonal Midn knockout (KO) PC12 cell models. Midn KO inhibited neurite outgrowth and neurofilament light chain (Nefl) gene expression. Although MIDN is mainly localized in the nucleus, it does not encode DNA-binding domains. We therefore hypothesized that MIDN might bind to certain transcription factors and regulate gene expression. Of the candidate transcription factors, we focused on early growth response 1 (EGR1) because it is required for neurite outgrowth and its target genes are downregulated by Midn KO. An interaction between MIDN and EGR1 was confirmed by immunoprecipitation. Surprisingly, although EGR1 protein levels were significantly increased in Midn KO cells, the binding of EGR1 to the Nefl promoter and resulting transcriptional activity were downregulated as measured by luciferase assay and chromatin immunoprecipitation quantitative real-time polymerase chain reaction. Overall, we identified the MIDN-dependent regulation of EGR1 function. This mechanism may be an underlying reason for the neurite outgrowth defects of Midn KO PC12 cells.

Consensus Guidance for Genetic Counseling in GBA1 Variants: A Focus on Parkinson's Disease.

Glucocerebrosidase (GBA1) variants constitute numerically the most common known genetic risk factor for Parkinson's disease (PD) and are distributed worldwide. Access to GBA1 genotyping varies across the world and even regionally within countries. Guidelines for GBA1 variant counseling are evolving. We review the current knowledge of the link between GBA1 and PD, and discuss the practicalities of GBA1 testing. Lastly, we provide a consensus for an approach to counseling people with GBA1 variants, notably the communication of PD risk. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Neoself-antigens are the primary target for autoreactive Tcells in human lupus.

Major histocompatibility complex class II (MHC-II) is the most significant genetic risk factor for systemic lupus erythematosus (SLE), but the nature of the self-antigens that trigger autoimmunity remains unclear. Unusual self-antigens, termed neoself-antigens, are presented on MHC-II in the absence of the invariant chain essential for peptide presentation. Here, we demonstrate that neoself-antigens are the primary target for autoreactive Tcells clonally expanded in SLE. When neoself-antigen presentation was induced by deleting the invariant chain in adult mice, neoself-reactive Tcells were clonally expanded, leading to the development of lupus-like disease. Furthermore, we found that neoself-reactive CD4+ Tcells were significantly expanded in SLE patients. A high frequency of Epstein-Barr virus reactivation is a risk factor for SLE. Neoself-reactive lupus Tcells were activated by Epstein-Barr-virus-reactivated cells through downregulation of the invariant chain. Together, our findings imply that neoself-antigen presentation by MHC-II plays a crucial role in the pathogenesis of SLE.

Alcohol Consumption and Cardiovascular Disease: A Narrative Review of Evolving Perspectives and Long-Term Implications

Cardiovascular illnesses remain the primary cause of death, accounting for at least 17.9 million fatalities per year and posing a significant public health problem because of its extensive predominance and effect on healthcare systems. The etiology of cardiovascular disease is complex and involves several environmental and lifestyle factors. Alcohol use is a highly important determinant because of its dual-edged effect on cardiovascular health. Multiple studies indicate that moderate alcohol consumption may have certain advantages, such as slight enhancements in lipid profiles. Conversely, excessive alcohol intake is associated with serious negative consequences, including cardiomyopathy, hypertension, arrhythmias, and even mortality. The aim of this study is to provide a comprehensive analysis of the several effects of alcohol on cardiovascular health and their understanding within the medical field over time. It uses an interpretative narrative review methodology and analyzes studies that focus on genetic risk factors, gender differences, and shifts in paradigms in recent years. This article highlights the need for obtaining a thorough understanding of the effects of alcohol on cardiovascular health to support public health guidelines and clinical practice, and it underscores the significance of including alcohol consumption into the broader context of cardiovascular risk management and identifies important subjects for further study.

Genetics and Epigenetic in Mental Health

Genetics and epigenetics play critical roles in mental health, offering insights into the complex interplay between biological predisposition and environmental influences in the development and progression of mental disorders. Genetic studies have identified numerous risk loci associated with conditions such as schizophrenia, bipolar disorder, and depression, highlighting the polygenic nature of these illnesses. However, the presence of genetic risk factors alone does not fully account for the variability in disease onset, severity, or response to treatment. This gap is increasingly understood through the lens of epigenetics, which involves heritable changes in gene expression that do not alter the DNA sequence itself but are influenced by environmental factors, such as stress, diet, and exposure to toxins. Epigenetic mechanisms, including DNA methylation, histone modification, and non-coding RNAs, can modulate gene activity in response to external stimuli, leading to long-lasting effects on brain function and behavior. These processes are particularly important during critical periods of brain development, where epigenetic modifications can shape neural circuits involved in emotion regulation, cognition, and stress response. Emerging research suggests that the interaction between genetic predisposition and epigenetic changes contributes to the heterogeneity observed in mental health disorders, explaining why individuals with similar genetic risks can have different outcomes. Understanding these intricate genetic and epigenetic networks is essential for developing personalized therapeutic strategies, which could revolutionize the prevention, diagnosis, and treatment of mental health conditions. Advances in this field hold the promise of identifying biomarkers for early intervention and creating targeted interventions that consider an individual’s unique genetic and epigenetic profile, ultimately improving mental health outcomes on a global scale.

Fifty Years of Psychiatric Classification and Epidemiology Interactions: What is a Mental Disorder?

Psychiatric clinical diagnostic formulation has evolved over time. The changes alter our understanding and our ability to provide a public health perspective on the epidemiology of mental disorders in large populations. Epidemiology is an important perspective and set of tools to assess prevalence, treated prevalence, untreated prevalence, individual risks for mental disorders, and possible links to the etiology of disorders by following the trails of environmental exposures, biological measures, interpersonal dynamics, and genetic risk factors. As communities develop health-care services to treat individuals with mental disorders, knowledge about their prevalence and treatment requirements is also important. Since severe mental disorders may require institutional care, the diagnostic criteria used may either protect an individual’s liability for dangerous behavior (i.e. the insanity defense) or be used to control political and social dissidents. The criteria may also be used to determine evidence-based treatment options and eligibility for disability benefits. In this paper, using my vantage points as a physician scientist and public health officer, with leadership positions in national federal and professional mental health organizations, I address the developments in these areas over the past 50 years that have influenced institutional positions in the U.S. National Institute of Mental Health, the World Health Organization, the American Psychiatric Association, and the Center for the Study of Traumatic Stress. These perspectives may aid the next generation of investigators to advance the epidemiological and mental disorder classification scientific fields.

Connecting genomic and proteomic signatures of amyloid burden in the brain.

Alzheimer's disease (AD) has a high heritable component characteristic of complex diseases, yet many of the genetic risk factors remain unknown. We combined genome-wide association studies (GWAS) on amyloid endophenotypes measured in cerebrospinal fluid (CSF) and positron emission tomography (PET) as surrogates of amyloid pathology, which may be helpful to understand the underlying biology of the disease. We performed a meta-analysis of GWAS of CSF Aβ42 and PET measures combining six independent cohorts (n=2,076). Due to the opposite effect direction of Aβ phenotypes in CSF and PET measures, only genetic signals in the opposite direction were considered for analysis (n=376,599). Polygenic risk scores (PRS) were calculated and evaluated for AD status and amyloid endophenotypes. We then searched the CSF proteome signature of brain amyloidosis using SOMAscan proteomic data (Ace cohort, n=1,008) and connected it with GWAS results of loci modulating amyloidosis. Finally, we compared our results with a large meta-analysis using publicly available datasets in CSF (n=13,409) and PET (n=13,116). This combined approach enabled the identification of overlapping genes and proteins associated with amyloid burden and the assessment of their biological significance using enrichment analyses. After filtering the meta-GWAS, we observed genome-wide significance in the rs429358- APOE locus and nine suggestive hits were annotated. We replicated the APOE loci using the large CSF-PET meta-GWAS and identified multiple AD-associated genes as well as the novel GADL1 locus. Additionally, we found a significant association between the AD PRS and amyloid levels, whereas no significant association was found between any Aβ PRS with AD risk. CSF SOMAscan analysis identified 1,387 FDR-significant proteins associated with CSF Aβ42 levels. The overlap among GWAS loci and proteins associated with amyloid burden was very poor (n=35). The enrichment analysis of overlapping hits strongly suggested several signalling pathways connecting amyloidosis with the anchored component of the plasma membrane, synapse physiology and mental disorders that were replicated in the large CSF-PET meta-analysis. The strategy of combining CSF and PET amyloid endophenotypes GWAS with CSF proteome analyses might be effective for identifying signals associated with the AD pathological process and elucidate causative molecular mechanisms behind the amyloid mobilization in AD.

Uncovering novel regulatory variants in carbohydrate metabolism: a comprehensive multi-omics study of glycemic traits in the Indian population.

Clinical biomarkers such as fasting glucose, HbA1c, and fasting insulin, which gauge glycemic status in the body, are highly influenced by diet. Indians are genetically predisposed to type 2 diabetes and their carbohydrate-centric diet further elevates the disease risk. Despite the combined influence of genetic and environmental risk factors, Indians have been inadequately explored in the studies of glycemic traits. Addressing this gap, we investigate the genetic architecture of glycemic traits at genome-wide level in 4927 Indians (without diabetes). Our analysis revealed numerous variants of sub-genome-wide significance, and their credibility was thoroughly assessed by integrating data from various levels. This identified key effector genes, ZNF470, DPP6, GXYLT2, PITPNM3, BEND7, and LORICRIN-PGLYRP3. While these genes were weakly linked with carbohydrate intake or glycemia earlier in other populations, our findings demonstrated a much stronger association in the Indian population. Associated genetic variants within these genes served as expression quantitative trait loci (eQTLs) in various gut tissues essential for digestion. Additionally, majority of these gut eQTLs functioned as methylation quantitative trait loci (meth-QTLs) observed in peripheral blood samples from 223 Indians, elucidating the underlying mechanism of their regulation of target gene expression. Specific co-localized eQTLs-meth-QTLs altered the binding affinity of transcription factors targeting crucial genes involved in glucose metabolism. Our study identifies previously unreported genetic variants that strongly influence the diet-glycemia relationship. These findings set the stage for future research into personalized lifestyle interventions integrating genetic insights with tailored dietary strategies to mitigate disease risk based on individual genetic profiles.

Advantages of Robotic Surgery for Patients of Reproductive Age with Endometrial Cancer

This review presents current knowledge on the surgical treatment of endometrial cancer in young patients. Endometrial cancer is the most common gynecological cancer in Europe. Higher morbidity is correlated with obesity, hypertension and diabetes, which are growing worldwide. However, endometrial cancer at an early age is very rare. The first line of treatment for this cancer is radical hysterectomy, which is controversial in young women. There is an alternative method of fertility-sparing treatment. However, there is a group of young patients for whom surgical treatment is recommended. According to European guidelines, minimally invasive surgery is recommended for endometrial cancer. The aim of the study was to present the advantages of robotic surgery for endometrial cancer detected at a young age. The procedure of radical treatment with robot-assisted laparoscopy is more precise. Better visualization and stabilization of instruments allow a shorter procedure time, a brief hospital stay and fewer complications. Quality of life may be at a similar level. Incisions after trocars are painless and more esthetic than a classical wound. Bilateral adnexectomy in endometrial cancer depends on age, molecular status of the cancer, stage, genetic risk factors and individual decision. Conclusions: Robotic surgery seems to be a better surgical method for endometrial cancer in younger patients.

Genetic regulation of ovulation rate and multiple births.

Ovulation rate in many mammalian species is controlled to regulate the numbers of offspring and maximise reproductive success. Pathways that regulate ovulation rate still respond to genetic and environmental factors and show considerable variation within and between species. Genetic segregation, positional cloning, and association studies have discovered numerous mutations and genetic risk factors that contribute to this variation. Notable among the discoveries has been the role of mutations in bone morphogenetic protein 15 (BMP15 ), growth differentiation factor 9 (GDF9 ) and bone morphogenetic protein receptor type 1B (BMPR1B ) from the intra-ovarian signalling pathway contributing to the evidence that signalling from the oocyte is the key driver in follicle regulation rather than circulating gonadotrophin concentrations. Multiple variants in different domains of BMP15 and GDF9 result in partial or complete loss of function of the proteins providing insights into their functional roles and differential regulation contributing to species differences in ovulation rate. Early success encouraged many more studies in prolific strains of sheep, cattle and goats providing a valuable catalogue of genetic variants of large effect increasing ovulation rate and litter size. More recently, genetic association studies are beginning to identify genetic risk factors with smaller effects. Most genes implicated are from pathways with defined roles in regulation of the ovarian function. However, some genomic regions suggest regulation by novel genes. Continuing genetic and related functional studies will add further to our understanding of the detailed regulation of ovulation rate and litter size with implications for health and animal production systems.

Immunobiology of primary sclerosing cholangitis.

Primary sclerosing cholangitis (PSC) is a chronic inflammatory progressive cholestatic liver disease. Genetic risk factors, presence of autoantibodies, the strong clinical link with inflammatory bowel disease (IBD), and associations with other autoimmune disorders all suggest a pivotal role for the immune system in PSC pathogenesis. In this review, we provide a comprehensive overview of recent immunobiology insights in PSC. A particular emphasis is given to immunological concepts such as tissue-residency and knowledge gained from novel technologies including single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics (ST). This review of the immunobiological landscape of PSC covers major immune cell types known to be enriched in PSC-diseased livers as well as recently described cell types whose biliary localization and contribution to PSC immunopathogenesis remain incompletely described. Finally, we emphasize the importance of time and space in relation to PSC heterogeneity as a key consideration for future studies interrogating the role of the immune system in PSC.

Genetic and environmental risk factors in autistic children

A complex neurodevelopmental disorder known as autism spectrum disorder (ASD) is characterized by difficulties with behavior, socialization, and communication. ASD has a complex etiology, with environmental and genetic variables playing a role in its development. The purpose of this research is to assess our current knowledge of the genetic predispositions and environmental exposures that raise a child's risk of autism spectrum disorder (ASD). To find important risk variables, we examined data from several epidemiological studies, genome-wide association studies (GWAS), and environmental health studies. Our results demonstrate the significant contribution that genetic mutations both inherited and de novo make to the increased risk of ASD. Critical environmental factors that we also discovered were maternal illnesses, prenatal pollution exposure, and dietary deficits. This integrated method emphasizes how important it is to take into account both environmental and genetic elements in order to better understand and maybe lower the risk of ASD.

The Epigenetic Contribution to the Pathogenesis of Psoriasis: Recent Advances.

Psoriasis is defined as a chronic autoimmune disorder of the skin in which abnormal proliferation and differentiation of keratinocytes are blamed as the central culprit of disease etiopathogenesis. A complex interplay between environmental factors and genetic risk factors has been suggested to trigger the disease. However, epigenetic regulation appears to connect external stimuli and genetic abnormalities in the development of psoriasis. The discordance in the prevalence of psoriasis between monozygotic twins and environmental factors that contribute to its onset have caused a paradigm shift regarding the mechanisms underlying the pathogenesis of this disease. Epigenetic dysregulation may be involved in aberrancies of keratinocyte differentiation, T-cell activation, and other plausible cells, leading to the initiation and perpetuation of psoriasis. Epigenetics is characterized by heritable alterations in the transcription of genes without nucleotide change and is commonly considered at three levels, i.e., DNA methylation, histone modifications, and microRNAs. To date, scientific evidence has indicated abnormal DNA methylation, histone modifications, and non-coding RNA transcription in psoriatic patients. In order to reverse aberrant epigenetic changes in psoriasis patients, several compounds and drugs (epi-drugs) have been developed to affect the major enzymes involved in the methylation of DNA, or the acetylation of histones, which aim to correct the aberrant methylation and acetylation patterns. A number of clinical trials have suggested the therapeutic potential of such drugs in the treatment of psoriasis. In the present review, we attempt to clarify recent findings with respect to epigenetic irregularities in psoriasis and discuss future challenges.

232. EPIDEMIOLOGY OF EOSINOPHILIC ESOPHAGITIS IN JAPAN: A POPULATION-BASED STUDY

Abstract Backgrounds Eosinophilic esophagitis (EoE) has been increasingly diagnosed in Western countries whilst there have been few general population-based studies in Asia. In addition, risk factors for EoE have not been examined completely. The aim of the study was to investigate the epidemiology and risk factors of EoE in Japanese general population. Methods We analyzed an employer-based health insurance claim database from January 2005 to September 2022. EoE cases were identified based on the International Classification of Diseases-tenth Revision code, K20.0. We calculated the incidence and prevalence of EoE using Poisson regression and binomial distribution with exact methods respectively. Using 10 times more matched controls for EoE cases, a nested case-control study identified potential risk factors for adult EoE. Results Of 15,200,895 individuals, 1,010 EoE cases were identified. The incidence and prevalence of EoE were 2.82 (95% CI 2.44–3.26) per 100,000 person-years and 10.68 (95% CI 10.01–11.37) per 100,000 people in 2022. Both rates had dramatically increased since 2017. smoking was associated with a 59% risk reduction of EoE whereas constant alcohol consumption was associated with a 63% increase in the risk of EoE. EoE was not associated with either body mass index or health-related diseases such as hypertension, diabetes mellitus, hyperuricemia, and dyslipidemia. Conclusion The incidence and prevalence of EoE in Japan has steadily increased over the past two decades. Nevertheless, EoE remains less common in Japan compared to Western countries. Factors contributing to the epidemiology of EoE on a global basis may improve our understanding of the contribution of genetic and environmental risk factors. In light of potential risk factors, further study is warranted to investigate whether lifestyle intervention can improve the management of EoE.

Comparing GBA1-Parkinson's disease and idiopathic Parkinson's disease: α-Synuclein oligomers and synaptic density as biomarkers in the skin biopsy.

The main genetic risk factors for Parkinson's disease (PD) are presently represented by variants in GBA1 gene encoding for the β-glucocerebrosidase (GCase). Searching for a peripheral biomarker that can be used for selecting and monitoring patients in clinical trials targeting GBA1-associated PD (GBA1-PD) is a current challenge. We previously demonstrated that α-synuclein oligomers expressed as proximity ligation assay (PLA) score in synaptic terminals of skin biopsy are a reliable biomarker for distinguishing idiopathic PD (iPD) from healthy controls (HC). This cross-sectional study investigates an unexplored cohort of GBA1-PD (n = 27) compared to 28 HC, and 36 iPD cases to (i) analyze α-synuclein oligomers and quantify them throughout PLA score, (ii) investigate GCase expression in brain and synaptic terminals targeting the sweat gland, (iii) unravel indicators that could differentiate patients with specific GBA1 mutations. PLA score discriminates GBA1-PD from HC with sensitivity = 88.9% (95% CI 70.84-97.65), specificity = 88.5% (95% CI 69.85-97.55), and PPV = 88.9% (95% CI 73.24-95.90), AUC value = 0.927 (95% CI 0.859-0.996). No difference was found between GBA1-PD patients and iPD, suggesting a common pathological pathway based on α-synuclein oligomers. GCase score did not differ in GBA1-PD, iPD, and HC in the synaptic terminals, whereas a positive correlation was found between PLA score and GCase score. Moreover, a significant increase in synaptic density was observed in GBA1-PD compared to iPD and HC (P < 0.0001). Employing ROC curve to discriminate GBA1-PD from iPD, we found an AUC value for synaptic density = 0.855 (95% CI 0.749-0.961) with sensitivity = 85.2% (95% CI 66.27%-95.81%), specificity = 77.1% (95% CI 59.86%-89.58%), and PPV = 74.19% (60.53%-84.35%). The highest synaptic density values were observed in p.N409S patients. This work points out to the value of both PLA score and synaptic density in distinguishing GBA1-PD from iPD and to their potential to stratify and monitor patients in the context of new pathway-specific therapeutic options.