Identification of Potential Causal Genes for Neurodegenerative Diseases by Mitochondria-Related Genome-Wide Mendelian Randomization.

Current research lacks comprehensive investigations into the potential causal link between mitochondrial-related genes and the risk of neurodegenerative diseases (NDDs). We aimed to identify potential causative genes for five NDDs through an examination of mitochondrial-related gene expression levels. Through the integration of summary statistics from expression quantitative trait loci (eQTL) datasets (human blood and brain tissue), mitochondrial DNA copy number (mtDNA-CN), and genome-wide association studies (GWAS) datasets of five NDDs from European ancestry, we conducted a Mendelian randomization (MR) analysis to explore the potential causal relationship between mitochondrial-related genes and Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Lewy body dementia (LBD). Sensitivity analysis and Bayesian colocalization were employed to validate this causal relationship. Through MR analysis, we have identified potential causal relationships between 12 mitochondria-related genes and AD, PD, ALS, and FTD overlapping with motor neuron disease (FTD_MND) in human blood or brain tissue. Bayesian colocalization analysis further confirms 9 causal genes, including NDUFS2, EARS2, and MRPL41 for AD; NDUFAF2, MALSU1, and METTL8 for PD; MYO19 and MRM1 for ALS; and FASTKD1 for FTD_MND. Importantly, in both human blood and brain tissue, NDUFS2 exhibits a significant pathogenic effect on AD, while NDUFAF2 demonstrates a robust protective effect on PD. Additionally, the mtDNA-CN plays a protected role in LBD (OR = 0.62, p = 0.031). This study presents evidence establishing a causal relationship between mitochondrial dysfunction and NDDs. Furthermore, the identified candidate genes may serve as potential targets for drug development aimed at preventing NDDs.

FGF4 ameliorates the liver inflammation by reducing M1 macrophage polarization in experimental autoimmune hepatitis.

BACKGROUND: The global prevalence of autoimmune hepatitis (AIH) is increasing due in part to the lack of effective pharmacotherapies. Growing evidence suggests that fibroblast growth factor 4 (FGF4) is crucial for diverse aspects of liver pathophysiology. However, its role in AIH remains unknown. Therefore, we investigated whether FGF4 can regulate M1 macrophage and thereby help treat liver inflammation in AIH. METHODS: We obtained transcriptome-sequencing and clinical data for patients with AIH. Mice were injected with concanavalin A to induce experimental autoimmune hepatitis (EAH). The mechanism of action of FGF4 was examined using macrophage cell lines and bone marrow-derived macrophages. RESULTS: We observed higher expression of markers associated with M1 and M2 macrophages in patients with AIH than that in individuals without AIH. EAH mice showed greater M1-macrophage polarization than control mice. The expression of M1-macrophage markers correlated positively with FGF4 expression. The loss of hepatic Fgf4 aggravated hepatic inflammation by increasing the abundance of M1 macrophages. In contrast, the pharmacological administration of FGF4 mitigated hepatic inflammation by reducing M1-macrophage levels. The efficacy of FGF4 treatment was compromised following the in vivo clearance of macrophage populations. Mechanistically, FGF4 treatment activated the phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT)-signal pathway in macrophages, which led to reduced M1 macrophages and hepatic inflammation. CONCLUSION: We identified FGF4 as a novel M1/M2 macrophage-phenotype regulator that acts through the PI3K-AKT-signaling pathway, suggesting that FGF4 may represent a novel target for treating inflammation in patients with AIH.

Systematic druggable genome-wide Mendelian randomization identifies therapeutic targets for sarcopenia.

BACKGROUND: There are no effective pharmacological treatments for sarcopenia. We aim to identify potential therapeutic targets for sarcopenia by integrating various publicly available datasets. METHODS: We integrated druggable genome data, cis-eQTL/cis-pQTL from human blood and skeletal muscle tissue, and GWAS summary data of sarcopenia-related traits to analyse the potential causal relationships between drug target genes and sarcopenia using the Mendelian Randomization (MR) method. Sensitivity analyses and Bayesian colocalization were employed to validate the causal relationships. We also assessed the side effects or additional indications of the identified drug targets using a phenome-wide MR (Phe-MR) approach and investigated actionable drugs for target genes using available databases. RESULTS: MR analysis identified 17 druggable genes with potential causation to sarcopenia in human blood or skeletal muscle tissue. Six of them (HP, HLA-DRA, MAP 3K3, MFGE8, COL15A1, and AURKA) were further confirmed by Bayesian colocalization (PPH4 > 90%). The up-regulation of HP [higher ALM (beta: 0.012, 95% CI: 0.007-0.018, P = 1.2*10-5) and higher grip strength (OR: 0.96, 95% CI: 0.94-0.98, P = 4.2*10-5)], MAP 3K3 [higher ALM (beta: 0.24, 95% CI: 0.21-0.26, P = 1.8*10-94), higher grip strength (OR: 0.82, 95% CI: 0.75-0.90, P = 2.1*10-5), and faster walking pace (beta: 0.03, 95% CI: 0.02-0.05, P = 8.5*10-6)], and MFGE8 [higher ALM (muscle eQTL, beta: 0.09, 95% CI: 0.06-0.11, P = 6.1*10-13; blood pQTL, beta: 0.05, 95% CI: 0.03-0.07, P = 3.8*10-09)], as well as the down-regulation of HLA-DRA [lower ALM (beta: -0.09, 95% CI: -0.11 to -0.08, P = 5.4*10-36) and lower grip strength (OR: 1.13, 95% CI: 1.07-1.20, P = 1.8*10-5)] and COL15A1 [higher ALM (muscle eQTL, beta: -0.07, 95% CI: -0.10 to -0.04, P = 3.4*10-07; blood pQTL, beta: -0.05, 95% CI: -0.06 to -0.03, P = 1.6*10-07)], decreased the risk of sarcopenia. AURKA in blood (beta: -0.16, 95% CI: -0.22 to -0.09, P = 2.1*10-06) and skeletal muscle (beta: 0.03, 95% CI: 0.02 to 0.05, P = 5.3*10-05) tissues showed an inverse relationship with sarcopenia risk. The Phe-MR indicated that the six potential therapeutic targets for sarcopenia had no significant adverse effects. Drug repurposing analysis supported zinc supplementation and collagenase clostridium histolyticum might be potential therapeutics for sarcopenia by activating HP and inhibiting COL15A1, respectively. CONCLUSIONS: Our research indicated MAP 3K3, MFGE8, COL15A1, HP, and HLA-DRA may serve as promising targets for sarcopenia, while the effectiveness of zinc supplementation and collagenase clostridium histolyticum for sarcopenia requires further validation.

Causal association and mediating effect of blood biochemical metabolic traits and brain image-derived endophenotypes on Alzheimer's disease.

Background: Recent genetic evidence supports that circulating biochemical and metabolic traits (BMTs) play a causal role in Alzheimer's disease (AD), which might be mediated by changes in brain structure. Here, we leveraged publicly available genome-wide association study data to investigate the intrinsic causal relationship between blood BMTs, brain image-derived phenotypes (IDPs) and AD. Methods: Utilizing the genetic variants associated with 760 blood BMTs and 172 brain IDPs as the exposure and the latest AD summary statistics as the outcome, we analyzed the causal relationship between blood BMTs and brain IDPs and AD by using a two-sample Mendelian randomization (MR) method. Additionally, we used two-step/mediation MR to study the mediating effect of brain IDPs between blood BMTs and AD. Results: Twenty-five traits for genetic evidence supporting a causal association with AD were identified, including 12 blood BMTs and 13 brain IDPs. For BMTs, glutamine consistently reduced the risk of AD in 3 datasets. For IDPs, specific alterations of cortical thickness (atrophy in frontal pole and insular lobe, and incrassation in superior parietal lobe) and subcortical volume (atrophy in hippocampus and its subgroups, left accumbens and left choroid plexus, and expansion in cerebral white matter) are vulnerable to AD. In the two-step/mediation MR analysis, superior parietal lobe, right hippocampal fissure and left accumbens were identified to play a potential mediating role among three blood BMTs and AD. Conclusions: The results obtained in our study suggest that 12 circulating BMTs and 13 brain IDPs play a causal role in AD. Importantly, a subset of BMTs exhibit shared genetic architecture and potentially causal relationships with brain structure, which may contribute to the alteration of brain IDPs in AD.

Loss of CHCHD2 Stability Coordinates with C1QBP/CHCHD2/CHCHD10 Complex Impairment to Mediate PD-Linked Mitochondrial Dysfunction.

Novel CHCHD2 mutations causing C-terminal truncation and interrupted CHCHD2 protein stability in Parkinson's disease (PD) patients were previously found. However, there is limited understanding of the underlying mechanism and impact of subsequent CHCHD2 loss-of-function on PD pathogenesis. The current study further identified the crucial motif (aa125-133) responsible for diminished CHCHD2 expression and the molecular interplay within the C1QBP/CHCHD2/CHCHD10 complex to regulate mitochondrial functions. Specifically, CHCHD2 deficiency led to decreased neural cell viability and mitochondrial structural and functional impairments, paralleling the upregulation of autophagy under cellular stresses. Meanwhile, as a binding partner of CHCHD2, C1QBP was found to regulate the stability of CHCHD2 and CHCHD10 proteins to maintain the integrity of the C1QBP/CHCHD2/CHCHD10 complex. Moreover, C1QBP-silenced neural cells displayed severe cell death phenotype along with mitochondrial damage that initiated a significant mitophagy process. Taken together, the evidence obtained from our in vitro and in vivo studies emphasized the critical role of CHCHD2 in regulating mitochondria functions via coordination among CHCHD2, CHCHD10, and C1QBP, suggesting the potential mechanism by which CHCHD2 function loss takes part in the progression of neurodegenerative diseases.

TBK1, a prioritized drug repurposing target for amyotrophic lateral sclerosis: evidence from druggable genome Mendelian randomization and pharmacological verification in vitro.

BACKGROUND: There is a lack of effective therapeutic strategies for amyotrophic lateral sclerosis (ALS); therefore, drug repurposing might provide a rapid approach to meet the urgent need for treatment. METHODS: To identify therapeutic targets associated with ALS, we conducted Mendelian randomization (MR) analysis and colocalization analysis using cis-eQTL of druggable gene and ALS GWAS data collections to determine annotated druggable gene targets that exhibited significant associations with ALS. By subsequent repurposing drug discovery coupled with inclusion criteria selection, we identified several drug candidates corresponding to their druggable gene targets that have been genetically validated. The pharmacological assays were then conducted to further assess the efficacy of genetics-supported repurposed drugs for potential ALS therapy in various cellular models. RESULTS: Through MR analysis, we identified potential ALS druggable genes in the blood, including TBK1 [OR 1.30, 95%CI (1.19, 1.42)], TNFSF12 [OR 1.36, 95%CI (1.19, 1.56)], GPX3 [OR 1.28, 95%CI (1.15, 1.43)], TNFSF13 [OR 0.45, 95%CI (0.32, 0.64)], and CD68 [OR 0.38, 95%CI (0.24, 0.58)]. Additionally, we identified potential ALS druggable genes in the brain, including RESP18 [OR 1.11, 95%CI (1.07, 1.16)], GPX3 [OR 0.57, 95%CI (0.48, 0.68)], GDF9 [OR 0.77, 95%CI (0.67, 0.88)], and PTPRN [OR 0.17, 95%CI (0.08, 0.34)]. Among them, TBK1, TNFSF12, RESP18, and GPX3 were confirmed in further colocalization analysis. We identified five drugs with repurposing opportunities targeting TBK1, TNFSF12, and GPX3, namely fostamatinib (R788), amlexanox (AMX), BIIB-023, RG-7212, and glutathione as potential repurposing drugs. R788 and AMX were prioritized due to their genetic supports, safety profiles, and cost-effectiveness evaluation. Further pharmacological analysis revealed that R788 and AMX mitigated neuroinflammation in ALS cell models characterized by overly active cGAS/STING signaling that was induced by MSA-2 or ALS-related toxic proteins (TDP-43 and SOD1), through the inhibition of TBK1 phosphorylation. CONCLUSIONS: Our MR analyses provided genetic evidence supporting TBK1, TNFSF12, RESP18, and GPX3 as druggable genes for ALS treatment. Among the drug candidates targeting the above genes with repurposing opportunities, FDA-approved drug-R788 and AMX served as effective TBK1 inhibitors. The subsequent pharmacological studies validated the potential of R788 and AMX for treating specific ALS subtypes through the inhibition of TBK1 phosphorylation.

Discovery and Exploration of Lipid-Modifying Drug Targets for ALS by Mendelian Randomization.

Observational studies have faced challenges in identifying replicable causes for amyotrophic lateral sclerosis (ALS). To address this, we employed an unbiased and data-driven approach to discover and explore potential causal exposures using two-sample Mendelian randomization (MR) analyses. In the phenotype discovery stage, we assessed 3948 environmental exposures from the UK Biobank and utilized ALS summary statistics (Europeans, 20,806 cases, 59,804 controls) as the outcome within a phenome-wide MR pipeline. Through a range of sensitivity analyses, two medication traits were identified to be protective for ALS. In the target exploration stage, we further conducted drug target MR analyses using the latest and trans-ethnic summary data on lipid-related traits and ALS (Europeans, 27,205 cases, 110,881 controls; East Asians, 1234 cases, 2850 controls). Our aim was to explore potential causal drug targets through six lipid-modifying effects. These comprehensive analyses revealed significant findings. Specifically, "cholesterol-lowering medication" and "atorvastatin" survived predefined criteria in the phenotype discovery stage and exhibited a protective effect on ALS. Further in the target exploration stage, we demonstrated that the therapeutic effect of APOB through LDL-lowering was associated with reduced ALS liability in Europeans (OR = 0.835, P = 5.61E - 5). Additionally, the therapeutic effect of APOA1 and LDLR through TC-lowering was associated with reduced ALS liability in East Asians (APOA1, OR = 0.859, P = 5.38E - 4; LDLR, OR = 0.910, P = 2.73E - 5). Overall, we propose potential protective effects of cholesterol-lowering drugs or statins on ALS risk from thousands of exposures. Our research also suggests APOB, APOA1, and LDLR as novel therapeutic targets for ALS and supports their potential protective mechanisms may be mediated by LDL-lowering or TC-lowering effects.

Expanding causal genes for Parkinson's disease via multi-omics analysis.

Genome­wide association studies (GWASs) have revealed numerous loci associated with Parkinson's disease (PD). However, some potential causal/risk genes were still not revealed and no etiological therapies are available. To find potential causal genes and explore genetically supported drug targets for PD is urgent. By integrating the expression quantitative trait loci (eQTL) and protein quantitative trait loci (pQTL) datasets from multiple tissues (blood, cerebrospinal fluid (CSF) and brain) and PD GWAS summary statistics, a pipeline combing Mendelian randomization (MR), Steiger filtering analysis, Bayesian colocalization, fine mapping, Protein-protein network and enrichment analysis were applied to identify potential causal genes for PD. As a result, GPNMB displayed a robust causal role for PD at the protein level in the blood, CSF and brain, and transcriptional level in the brain, while the protective role of CD38 (in brain pQTL and eQTL) was also identified. We also found inconsistent roles of DGKQ on PD between protein and mRNA levels. Another 9 proteins (CTSB, ARSA, SEC23IP, CD84, ENTPD1, FCGR2B, BAG3, SNCA, FCGR2A) were associated with the risk for PD based on only a single pQTL after multiple corrections. We also identified some proteins' interactions with known PD causative genes and therapeutic targets. In conclusion, this study suggested GPNMB, CD38, and DGKQ may act in the pathogenesis of PD, but whether the other proteins involved in PD needs more evidence. These findings would help to uncover the genes underlying PD and prioritize targets for future therapeutic interventions.

Systematic druggable genome-wide Mendelian randomisation identifies therapeutic targets for Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is the leading cause of dementia. Currently, there are no effective disease-modifying treatments for AD. Mendelian randomisation (MR) has been widely used to repurpose licensed drugs and discover novel therapeutic targets. Thus, we aimed to identify novel therapeutic targets for AD and analyse their pathophysiological mechanisms and potential side effects. METHODS: A two-sample MR integrating the identified druggable genes was performed to estimate the causal effects of blood and brain druggable expression quantitative trait loci (eQTLs) on AD. A repeat study was conducted using different blood and brain eQTL data sources to validate the identified genes. Using AD markers with available genome-wide association studies data, we evaluated the causal relationship between established AD markers to explore possible mechanisms. Finally, the potential side effects of the druggable genes for AD treatment were assessed using a phenome-wide MR. RESULTS: Overall, 5883 unique druggable genes were aggregated; 33 unique potential druggable genes for AD were identified in at least one dataset (brain or blood), and 5 were validated in a different dataset. Among them, three prior druggable genes (epoxide hydrolase 2 (EPHX2), SERPINB1 and SIGLEC11) reached significant levels in both blood and brain tissues. EPHX2 may mediate the pathogenesis of AD by affecting the entire hippocampal volume. Further phenome-wide MR analysis revealed no potential side effects of treatments targeting EPHX2, SERPINB1 or SIGLEC11. CONCLUSIONS: This study provides genetic evidence supporting the potential therapeutic benefits of targeting the three druggable genes for AD treatment, which will be useful for prioritising AD drug development.

Identifying novel genes for amyotrophic lateral sclerosis by integrating human brain proteomes with genome-wide association data.

BACKGROUND: Genome-Wide Association Studies (GWAS) have identified numerous risk genes for Amyotrophic Lateral Sclerosis (ALS); however, the mechanisms by which these loci confer ALS risk are uncertain. This study aims to identify novel causal proteins in the brains of patients with ALS using an integrative analytical pipeline. METHODS: Using the datasets of Protein Quantitative Trait Loci (pQTL) (NpQTL1 = 376, NpQTL2 = 152), expression QTL (eQTL) (N = 452), and the largest ALS GWAS (NALS=27,205, NControls = 110,881), we performed a systematic analytical pipeline including Proteome-Wide Association Study (PWAS), Mendelian Randomization (MR), Bayesian colocalization, and Transcriptome-Wide Association Study (TWAS) to identify novel causal proteins for ALS in the brain. RESULTS: Using PWAS, we found that the altered protein abundance of 12 genes in the brain was associated with ALS. Three genes (SCFD1, SARM1 and CAMLG) were identified as lead causal genes for ALS with solid evidence (False discovery rate < 0.05, in MR analysis; PPH4 > 80% for Bayesian colocalization). Specifically, an increased abundance of SCFD1 and CAMLG led to an increased risk of ALS, whereas a higher abundance of SARM1 led to a decreased risk of developing ALS. TWAS showed that SCFD1 and CAMLG were related to ALS at the transcriptional level. CONCLUSIONS: SCFD1, CAMLG, and SARM1 exhibited robust associations and causality with ALS. The study findings provide novel clues for identifying potential therapeutic targets in ALS. Further studies are required to explore the mechanisms underlying the identified genes.

Risk factors of amyotrophic lateral sclerosis: a global meta-summary.

Background: The etiology of amyotrophic lateral sclerosis (ALS) remains largely unknown. This study aimed to summarize the relationship between ALS and its genetic and non-genetic risk factors. Method: A search of relevant literature from PubMed, Embase, and Cochrane Database from inception to December 2022 was performed. Random-effects or fixed-effects models were performed by Stata MP 15.0 to pool multivariate or adjusted ratios (OR). PROSPERO registration number: CRD42022301549. Results: 230 eligible studies were included, of which 67 involved 22 non-genetic factors, and 163 involved genetic factors. Four aspects of non-genetic factors, including lifestyle, environmental and occupational exposures, pre-existing diseases/comorbidity and medical exposures, and others, were analyzed. Exposure to heavy metals (OR = 1.79), pesticides (OR = 1.46), solvents (OR = 1.37), previous head trauma (OR = 1.37), military service (OR = 1.29), stroke (OR = 1.26), magnetic field (OR = 1.22) and hypertension (OR = 1.04) are significant risk factors, but use of antidiabetics (OR = 0.52), high BMI (OR = 0.60 for obese and overweight vs. normal and underweight), living in urban (OR = 0.70), diabetes mellitus (OR = 0.83), and kidney disease (OR = 0.84) decrease the risk for ALS. In addition, eight common ALS-related genes were evaluated, the mutation frequencies of these genes were ranked from highest to lowest as SOD1 (2.2%), C9orf72 (2.1%), ATXN2 (1.7%), FUS (1.7%), TARDBP (0.8%), VCP (0.6%), UBQLN2(0.6%) and SQSTM1 (0.6%) in all the ALS patients. Conclusions: Our findings suggested that effective intervention for risk exposure and timely modification of lifestyle might prevent the occurrence of ALS. Genetic mutations are important risk factors for ALS and it is essential to detect genetic mutations correctly and scientifically. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=301549, identifier: CRD42022301549.

Protective effect of antihypertensive drugs on the risk of Parkinson's disease lacks causal evidence from mendelian randomization.

Background: Evidence from observational studies concerning the causal role of blood pressure (BP) and antihypertensive medications (AHM) on Parkinson's disease (PD) remains inconclusive. A two-sample Mendelian randomization (MR) study was performed to evaluate the unconfounded association of genetic proxies for BP and first-line AHMs with PD. Methods: Instrumental variables (IV) from the genome-wide association study (GWAS) for BP traits were used to proxy systolic BP (SBP), diastolic BP, and pulse pressure. SBP-associated variants either located within encoding regions or associated with the expression of AHM targets were selected and then scaled to proxy therapeutic inhibition of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, ß-blockers, calcium channel blockers, and thiazides. Positive control analyses on coronary heart disease (CHD) and stroke were conducted to validate the IV selection. Summary data from GWAS for PD risk and PD age at onset (AAO) were used as outcomes. Results: In positive control analyses, genetically determined BP traits and AHMs closely mimicked the observed causal effect on CHD and stroke, confirming the validity of IV selection methodology. In primary analyses, although genetic proxies identified by "encoding region-based method" for ß-blockers were suggestively associated with a delayed PD AAO (Beta: 0.115; 95% CI: 0.021, 0.208; p = 1.63E-2; per 10-mmHg lower), sensitivity analyses failed to support this association. Additionally, MR analyses found little evidence that genetically predicted BP traits, overall AHM, or other AHMs affected PD risk or AAO. Conclusion: Our data suggest that BP and commonly prescribed AHMs may not have a prominent role in PD etiology.

Signature of miRNAs derived from the circulating exosomes of patients with amyotrophic lateral sclerosis.

Background: Amyotrophic lateral sclerosis (ALS) is a progressive, fatal neurodegenerative disorder (NDS) with unclear pathophysiology and few therapeutic options. Mutations in SOD1 and C9orf72 are the most common in Asian and Caucasian patients with ALS, respectively. Aberrant (microRNAs) miRNAs found in patients with gene-mutated ALS may be involved in the pathogenesis of gene-specific ALS and sporadic ALS (SALS). The aim of this study was to screen for differentially expressed miRNAs from exosomes in patients with ALS and healthy controls (HCs) and to construct a miRNA-based diagnostic model to classify patients and HCs. Methods: We compared circulating exosome-derived miRNAs of patients with ALS and HCs using the following two cohorts: a discovery cohort (three patients with SOD1-mutated ALS, three patients with C9orf72-mutated ALS, and three HCs) analyzed by microarray and a validation cohort (16 patients with gene-mutated ALS, 65 patients with SALS, and 61 HCs) confirmed by RT-qPCR. The support vector machine (SVM) model was used to help diagnose ALS using five differentially expressed miRNAs between SALS and HCs. Results: A total of 64 differentially expressed miRNAs in patients with SOD1-mutated ALS and 128 differentially expressed miRNAs in patients with C9orf72-mutated ALS were obtained by microarray compared to HCs. Of these, 11 overlapping dysregulated miRNAs were identified in both groups. Among the 14 top-hit candidate miRNAs validated by RT-qPCR, hsa-miR-34a-3p was specifically downregulated in patients with SOD1-mutated ALS, while hsa-miR-1306-3p was downregulated in ALS patients with both SOD1 and C9orf72 mutations. In addition, hsa-miR-199a-3p and hsa-miR-30b-5p were upregulated significantly in patients with SALS, while hsa-miR-501-3p, hsa-miR-103a-2-5p, and hsa-miR-181d-5p had a trend to be upregulated. The SVM diagnostic model used five miRNAs as features to distinguish ALS from HCs in our cohort with an area under receiver operating characteristic curve (AUC) of 0.80. Conclusion: Our study identified aberrant miRNAs from exosomes of SALS and ALS patients with SOD1/C9orf72 mutations and provided additional evidence that aberrant miRNAs were involved in the pathogenesis of ALS regardless of the presence or absence of the gene mutation. The machine learning algorithm had high accuracy in predicting the diagnosis of ALS, shedding light on the foundation for the clinical application of blood tests in the diagnosis of ALS, and revealing the pathological mechanisms of the disease.

Production of a human iPSC line from an early-onset Parkinson's disease patient with a novel CHCHD2 gene truncated mutation.

CHCHD2 mutations have been reported to cause Parkinson's disease (PD) by a loss of function in mitochondria. Most reported mutations, however, were missense, which was not the perfect model for a study of haploinsufficiency. Here, a truncated mutation, CHCHD2 p.Pro53Alafs*38, was identified in one familial early-onset PD patient. We generated a human-induced pluripotent stem cell (iPSC) line WCHSCUi001-A from this patient. The generated iPSCs resembled human embryonic stem cells, expressed pluripotency markers, exhibited a normal karyotype and could be differentiated into three germ layers in vitro. This line will be valuable for investigating the disease mechanisms and screening candidate drugs.

CASC15 Gene Polymorphisms and Glioma Susceptibility in Chinese Children.

OBJECTIVE: Gliomas are the most common tumors in the central nervous system. The cancer susceptibility candidate 15 (CASC15) gene has been reported to be a susceptibility gene for several types of cancer. No studies have been carried out on the predisposing effect of CASC15 gene single nucleotide polymorphisms (SNPs) on glioma risk. METHODS: In order to determine whether CASC15 gene SNPs are involved in glioma susceptibility, the first association study in a relatively large sample, which consisted of 171 patients and 228 healthy controls recruited from China, was performed. The contribution of SNPs (rs6939340 A>G, rs4712653 T>C and rs9295536 C>A) to the risk of glioma was evaluated by multinomial logistic regression, based on the calculation of the odds ratio (OR) and 95% confidence interval (CI). RESULTS: In the single locus and combined analysis, it was revealed that the genetic risk score had no significant associations between CASC15 gene SNPs and glioma risk. However, in the stratified analysis, a significant decrease in risk of glioma was observed in subjects of <60 months old with the rs4712653 TT genotype, when compared to those with the CC/CT genotype (OR=0.12, 95% CI=0.02-0.91, P=0.041). CONCLUSION: The present study provides referential evidence on the association between the genetic predisposition of the CASC15 gene and glioma risk in Chinese children. However, more well-designed case-control studies and functional experiments are needed to further explore the role of CASC15 gene SNPs.

The mutation spectrum of Parkinson-disease-related genes in early-onset Parkinson's disease in ethnic Chinese.

BACKGROUND AND PURPOSE: Recent genetic progress has shown many causative/risk genes linked to Parkinson's disease (PD), mainly in patients of European ancestry. The study aimed to investigate the PD-related genes and determine the mutational spectrum of early-onset PD in ethnic Chinese. METHODS: In this study, whole-exome sequencing and/or gene dosage analysis were performed in 704 early-onset PD (EOPD) patients (onset age ≤45 years) and 1866 controls. Twenty-six PD-related genes and 20 other genes linked to neurodegenerative and lysosome diseases were analysed. RESULTS: Eighty-two (11.6%, 82/704) EOPD patients carrying rare pathogenic/likely pathogenic variants in PD-related genes were identified. The mutation frequency in autosomal recessive inheritance EOPD (42.9%, 27/63) was much higher than that in autosomal dominant inheritance EOPD (0.9%, 12/110) or sporadic EOPD (8.1%, 43/531). Bi-allelic mutations in PRKN were the most frequent, accounting for 5.1% of EOPD cases. Three common pathogenic variants, p.A53V in SNCA, p.G284R in PRKN and p.P53Afs*38 in CHCHD2, occur exclusively in Asians. The putative damaging variants from GBA, PRKN, DJ1, PLA2G6 and GCH1 contributed to the collective risk for EOPD. Notably, the protein-truncating variants in CHCHD2 were enriched in EOPD, especially for p.P53Afs*38, which was also found in three patients from an independent cohort of patients with late-onset PD (n = 1300). Functional experiments confirmed that truncated CHCHD2 variants cause loss of function and are linked to mitochondrial dysfunction. CONCLUSIONS: Our study reveals that the genetic spectrum of EOPD in Chinese, which may help develop genetic scanning strategies, provided more evidence supporting CHCHD2 in PD.

miRNA-432 and SLC38A1 as Predictors of Hepatocellular Carcinoma Complicated with Alcoholic Steatohepatitis.

Alcoholic steatohepatitis (ASH) is asymptomatic in the early stages and is typically advanced at the time of diagnosis. With the global rise in alcohol abuse, ASH is currently among the most detrimental diseases around the world. Hepatocellular carcinoma (HCC) is one of the final outcomes of numerous liver diseases. However, at present, HCC screening is mostly focused on liver cancer development. Moreover, there is no effective biomarker to predict the prognosis and recurrence of liver cancer. Meanwhile, there are limited studies on the prognosis and recurrence of HCC patients complicated with ASH. In this study, using bioinformatic analysis as well as cellular and animal models, we screened the differentially expressed (DE) miRNA-432 and SLC38A1 gene in ASH. Based on our analysis, miRNA-432 targeted SLC38A1, and the levels of miRNA-432 and SLC38A1 could accurately predict the overall survival (OS) and relapse free survival (RFS) in patients with liver cancer. Hence, these two genetic elements have the potential to synergistically predict the prognosis and recurrence of HCC complicated with ASH.

Genetic factors for survival in amyotrophic lateral sclerosis: an integrated approach combining a systematic review, pairwise and network meta-analysis.

BACKGROUND: The time of survival in patients with amyotrophic lateral sclerosis (ALS) varies greatly, and the genetic factors that contribute to the survival of ALS are not well studied. There is a lack of a comprehensive study to elucidate the role of genetic factors in the survival of ALS. METHODS: The published studies were systematically searched and obtained from PubMed, EMBASE, and the Cochrane Library without any language restrictions from inception to Oct 27, 2021. A network meta-analysis for ALS causative/risk genes and a systematic review and pairwise meta-analysis for other genetic modifiers were conducted. The PROSPERO registration number: CRD42022311646. RESULTS: A total of 29,764 potentially relevant references were identified, and 71 papers were eligible for analysis based on pre-decided criteria, including 35 articles in network meta-analysis for 9 ALS causative/risk genes, 17 articles in pairwise meta-analysis for four genetic modifiers, and 19 articles described in the systematic review. Variants in three genes, including ATXN2 (HR: 3.6), C9orf72 (HR: 1.6), and FUS (HR:1.8), were associated with short survival of ALS, but such association was not identified in SOD1, TARDBP, TBK1, NEK1, UBQLN2, and CCNF. In addition, UNC13A rs12608932 CC genotype and ZNF521B rs2275294 C allele also caused a shorter survival of ALS; however, APOE ε4 allele and KIFAP3 rs1541160 did not be found to have any effect on the survival of ALS. CONCLUSIONS: Our study summarized and contrasted evidence for prognostic genetic factors in ALS and would help to understand ALS pathogenesis and guide clinical trials and drug development.