Genes in human obesity loci are causal obesity genes in C. elegans

Obesity and its associated metabolic syndrome are a leading cause of morbidity and mortality in the United States. Given the disease’s heavy burden on patients and the healthcare system, there has been increased interest in identifying pharmacological targets for the treatment and prevention of obesity. Towards this end, genome-wide association studies (GWAS) have identified hundreds of human genetic variants associated with obesity. The next challenge is to experimentally define which of these variants are causally linked to obesity, and could therefore become targets for the treatment or prevention of obesity. Here we employ high-throughput in vivo RNAi screening to test for causality 293 C. elegans orthologs of human obesity-candidate genes reported in GWAS. We RNAi screened these 293 genes in C. elegans subject to two different feeding regimens: (1) regular diet, and (2) high-fructose diet, which we developed and present here as an invertebrate model of diet-induced obesity (DIO). We report 14 genes that promote obesity and 3 genes that prevent DIO when silenced in C. elegans. Further, we show that knock-down of the 3 DIO genes not only prevents excessive fat accumulation in primary and ectopic fat depots but also improves the health and extends the lifespan of C. elegans overconsuming fructose. Importantly, the direction of the association between expression variants in these loci and obesity in mice and humans matches the phenotypic outcome of the loss-of-function of the C. elegans ortholog genes, supporting the notion that some of these genes would be causally linked to obesity across phylogeny. Therefore, in addition to defining causality for several genes so far merely correlated with obesity, this study demonstrates the value of model systems compatible with in vivo high-throughput genetic screening to causally link GWAS gene candidates to human diseases.

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A High-Throughput, Seedling Screen for Plant Immunity

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-10-19-0295-ta ◽

2020 ◽

Vol 33 (3) ◽

pp. 394-401

Author(s):

Alexandre Martel ◽

Timothy Lo ◽

Darrell Desveaux ◽

David S. Guttman

Keyword(s):

Pseudomonas Syringae ◽

High Throughput ◽

Biological Diversity ◽

Association Studies ◽

Plant Immunity ◽

Genome Wide Association Studies ◽

Pathogen Effector ◽

Immunity Genes ◽

Microbe Interactions

An understanding of how biological diversity affects plant–microbe interactions is becoming increasingly important, particularly with respect to components of the pathogen effector arsenal and the plant immune system. Although technological improvements have greatly advanced our ability to examine molecular sequences and interactions, relatively few advances have been made that facilitate high-throughput, in vivo pathology screens. Here, we present a high-throughput, microplate-based, nondestructive seedling pathology assay, and apply it to identify Arabidopsis thaliana effector-triggered immunity (ETI) responses against Pseudomonas syringae type III secreted effectors. The assay was carried out in a 48-well microplate format with spray inoculation, and disease symptoms were quantitatively recorded in a semiautomated manner, thereby greatly reducing both time and costs. The assay requires only slight modifications of common labware and uses no proprietary software. We validated the assay by recapitulating known ETI responses induced by P. syringae in Arabidopsis. We also demonstrated that we can quantitatively differentiate responses from a diversity of plant genotypes grown in the same microplate. Finally, we showed that the results obtained from our assay can be used to perform genome-wide association studies to identify host immunity genes, recapitulating results that have been independently obtained with mature plants.

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Liver and Statins: A Critical Appraisal of the Evidence

Current Medicinal Chemistry ◽

10.2174/0929867325666180327095441 ◽

2019 ◽

Vol 25 (42) ◽

pp. 5835-5846 ◽

Cited By ~ 6

Author(s):

Anna Licata ◽

Antonina Giammanco ◽

Maria Giovanna Minissale ◽

Salvatore Pagano ◽

Salvatore Petta ◽

...

Keyword(s):

Adverse Events ◽

Association Studies ◽

Organic Anion ◽

Genome Wide Association Studies ◽

Drug Induced ◽

Drug Induced Liver Injury ◽

Organic Anion Transporting Polypeptide ◽

Treatment And Prevention ◽

Genome Wide ◽

Underlying Mechanisms

Adverse drug reactions (ADRs) represent an important cause of morbidity and mortality worldwide. Statins are a class of drugs whose main adverse effects are drug-induced liver injury (DILI) and myopathy. Some of these may be predictable, due to their pharmacokinetic and pharmacodynamic properties, while others, unfortunately, are idiosyncratic. Genetic factors may also influence patient susceptibility to DILI and myopathy in the case of statins. This review will first discuss the role of statins in cardiovascular disease treatment and prevention and the underlying mechanisms of action. Furthermore, to explore the susceptibility of statin-induced adverse events such as myopathy and hepatotoxicity, it will then focus on the recent Genome-Wide Association Studies (GWAS) concerning the transporter genes, Cytochrome P450 (CYP), organic anion-transporting polypeptide (OATP) and ABCB1 and ABCC1, which seem to play a role in the development of clinically relevant adverse events. Finally, we appraise the evidence for and against the use of statins in metabolic syndrome and in HCV-infected patients, in terms of their safety and efficacy in cardiovascular events.

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GWAS of serum ALT and AST reveals an association of SLC30A10 Thr95Ile with hypermanganesemia symptoms

Nature Communications ◽

10.1038/s41467-021-24563-1 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Lucas D. Ward ◽

Ho-Chou Tu ◽

Chelsea B. Quenneville ◽

Shira Tsour ◽

Alexander O. Flynn-Carroll ◽

...

Keyword(s):

Bile Duct ◽

Extrahepatic Bile Duct ◽

Association Studies ◽

Missense Variant ◽

Deficiency Anemia ◽

Genome Wide Association Studies ◽

Loss Of Function ◽

Extrahepatic Bile Duct Cancer ◽

Hepatocellular Damage ◽

Increased Risk

AbstractUnderstanding mechanisms of hepatocellular damage may lead to new treatments for liver disease, and genome-wide association studies (GWAS) of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) serum activities have proven useful for investigating liver biology. Here we report 100 loci associating with both enzymes, using GWAS across 411,048 subjects in the UK Biobank. The rare missense variant SLC30A10 Thr95Ile (rs188273166) associates with the largest elevation of both enzymes, and this association replicates in the DiscovEHR study. SLC30A10 excretes manganese from the liver to the bile duct, and rare homozygous loss of function causes the syndrome hypermanganesemia with dystonia-1 (HMNDYT1) which involves cirrhosis. Consistent with hematological symptoms of hypermanganesemia, SLC30A10 Thr95Ile carriers have increased hematocrit and risk of iron deficiency anemia. Carriers also have increased risk of extrahepatic bile duct cancer. These results suggest that genetic variation in SLC30A10 adversely affects more individuals than patients with diagnosed HMNDYT1.

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Genetic architecture of schizophrenia: a review of major advancements

Psychological Medicine ◽

10.1017/s0033291720005334 ◽

2021 ◽

pp. 1-10

Author(s):

Sophie E. Legge ◽

Marcos L. Santoro ◽

Sathish Periyasamy ◽

Adeniran Okewole ◽

Arsalan Arsalan ◽

...

Keyword(s):

Genetic Architecture ◽

Association Studies ◽

Copy Number Variants ◽

Risk Scores ◽

Genome Wide Association Studies ◽

Loss Of Function ◽

Genetic Loci ◽

Significant Enrichment ◽

High Heritability ◽

Coding Variants

Abstract Schizophrenia is a severe psychiatric disorder with high heritability. Consortia efforts and technological advancements have led to a substantial increase in knowledge of the genetic architecture of schizophrenia over the past decade. In this article, we provide an overview of the current understanding of the genetics of schizophrenia, outline remaining challenges, and summarise future directions of research. World-wide collaborations have resulted in genome-wide association studies (GWAS) in over 56 000 schizophrenia cases and 78 000 controls, which identified 176 distinct genetic loci. The latest GWAS from the Psychiatric Genetics Consortium, available as a pre-print, indicates that 270 distinct common genetic loci have now been associated with schizophrenia. Polygenic risk scores can currently explain around 7.7% of the variance in schizophrenia case-control status. Rare variant studies have implicated eight rare copy-number variants, and an increased burden of loss-of-function variants in SETD1A, as increasing the risk of schizophrenia. The latest exome sequencing study, available as a pre-print, implicates a burden of rare coding variants in a further nine genes. Gene-set analyses have demonstrated significant enrichment of both common and rare genetic variants associated with schizophrenia in synaptic pathways. To address current challenges, future genetic studies of schizophrenia need increased sample sizes from more diverse populations. Continued expansion of international collaboration will likely identify new genetic regions, improve fine-mapping to identify causal variants, and increase our understanding of the biology and mechanisms of schizophrenia.

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Cis-Segregation of c.1171C>T Stop Codon (p.R391*) in SERPINC1 Gene and c.1691G>A Transition (p.R506Q) in F5 Gene and Selected GWAS Multilocus Approach in Inherited Thrombophilia

Genes ◽

10.3390/genes12060934 ◽

2021 ◽

Vol 12 (6) ◽

pp. 934

Author(s):

Donato Gemmati ◽

Giovanna Longo ◽

Eugenia Franchini ◽

Juliana Araujo Silva ◽

Ines Gallo ◽

...

Keyword(s):

At Risk ◽

Stop Codon ◽

Association Studies ◽

Premature Stop Codon ◽

Large Family ◽

Genome Wide Association Studies ◽

Loss Of Function ◽

Gene Markers ◽

Inherited Thrombophilia ◽

Fv Leiden

Inherited thrombophilia (e.g., venous thromboembolism, VTE) is due to rare loss-of-function mutations in anticoagulant factors genes (i.e., SERPINC1, PROC, PROS1), common gain-of-function mutations in procoagulant factors genes (i.e., F5, F2), and acquired risk conditions. Genome Wide Association Studies (GWAS) recently recognized several genes associated with VTE though gene defects may unpredictably remain asymptomatic, so calculating the individual genetic predisposition is a challenging task. We investigated a large family with severe, recurrent, early-onset VTE in which two sisters experienced VTE during pregnancies characterized by a perinatal in-utero thrombosis in the newborn and a life-saving pregnancy-interruption because of massive VTE, respectively. A nonsense mutation (CGA > TGA) generating a premature stop-codon (c.1171C>T; p.R391*) in the exon 6 of SERPINC1 gene (1q25.1) causing Antithrombin (AT) deficiency and the common missense mutation (c.1691G>A; p.R506Q) in the exon 10 of F5 gene (1q24.2) (i.e., FV Leiden; rs6025) were coinherited in all the symptomatic members investigated suspecting a cis-segregation further confirmed by STR-linkage-analyses [i.e., SERPINC1 IVS5 (ATT)5–18, F5 IVS2 (AT)6–33 and F5 IVS11 (GT)12–16] and SERPINC1 intragenic variants (i.e., rs5878 and rs677). A multilocus investigation of blood-coagulation balance genes detected the coexistence of FV Leiden (rs6025) in trans with FV HR2-haplotype (p.H1299R; rs1800595) in the aborted fetus, and F11 rs2289252, F12 rs1801020, F13A1 rs5985, and KNG1 rs710446 in the newborn and other members. Common selected gene variants may strongly synergize with less common mutations tuning potential life-threatening conditions when combined with rare severest mutations. Merging classic and newly GWAS-identified gene markers in at risk families is mandatory for VTE risk estimation in the clinical practice, avoiding partial risk score evaluation in unrecognized at risk patients.

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Sequencing of 53,831 diverse genomes from the NHLBI TOPMed Program

Nature ◽

10.1038/s41586-021-03205-y ◽

2021 ◽

Vol 590 (7845) ◽

pp. 290-299 ◽

Cited By ~ 22

Author(s):

Daniel Taliun ◽

◽

Daniel N. Harris ◽

Michael D. Kessler ◽

Jedidiah Carlson ◽

...

Keyword(s):

Rare Variants ◽

Sequence Data ◽

Association Studies ◽

Genotype Imputation ◽

Genome Wide Association Studies ◽

Phenotypic Data ◽

Treatment And Prevention ◽

Genome Wide ◽

Diverse Backgrounds ◽

Unmapped Reads

AbstractThe Trans-Omics for Precision Medicine (TOPMed) programme seeks to elucidate the genetic architecture and biology of heart, lung, blood and sleep disorders, with the ultimate goal of improving diagnosis, treatment and prevention of these diseases. The initial phases of the programme focused on whole-genome sequencing of individuals with rich phenotypic data and diverse backgrounds. Here we describe the TOPMed goals and design as well as the available resources and early insights obtained from the sequence data. The resources include a variant browser, a genotype imputation server, and genomic and phenotypic data that are available through dbGaP (Database of Genotypes and Phenotypes)1. In the first 53,831 TOPMed samples, we detected more than 400 million single-nucleotide and insertion or deletion variants after alignment with the reference genome. Additional previously undescribed variants were detected through assembly of unmapped reads and customized analysis in highly variable loci. Among the more than 400 million detected variants, 97% have frequencies of less than 1% and 46% are singletons that are present in only one individual (53% among unrelated individuals). These rare variants provide insights into mutational processes and recent human evolutionary history. The extensive catalogue of genetic variation in TOPMed studies provides unique opportunities for exploring the contributions of rare and noncoding sequence variants to phenotypic variation. Furthermore, combining TOPMed haplotypes with modern imputation methods improves the power and reach of genome-wide association studies to include variants down to a frequency of approximately 0.01%.

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Sept8/SEPTIN8 involvement in cellular structure and kidney damage is identified by genetic mapping and a novel human tubule hypoxic model

Scientific Reports ◽

10.1038/s41598-021-81550-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Gregory R. Keele ◽

Jeremy W. Prokop ◽

Hong He ◽

Katie Holl ◽

John Littrell ◽

...

Keyword(s):

Complex Traits ◽

Genetic Model ◽

Association Studies ◽

Model Systems ◽

Linear Mixed Effect Model ◽

Genome Wide Association Studies ◽

Tubulointerstitial Injury ◽

Heritable Variation ◽

Mixed Effect

AbstractChronic kidney disease (CKD), which can ultimately progress to kidney failure, is influenced by genetics and the environment. Genes identified in human genome wide association studies (GWAS) explain only a small proportion of the heritable variation and lack functional validation, indicating the need for additional model systems. Outbred heterogeneous stock (HS) rats have been used for genetic fine-mapping of complex traits, but have not previously been used for CKD traits. We performed GWAS for urinary protein excretion (UPE) and CKD related serum biochemistries in 245 male HS rats. Quantitative trait loci (QTL) were identified using a linear mixed effect model that tested for association with imputed genotypes. Candidate genes were identified using bioinformatics tools and targeted RNAseq followed by testing in a novel in vitro model of human tubule, hypoxia-induced damage. We identified two QTL for UPE and five for serum biochemistries. Protein modeling identified a missense variant within Septin 8 (Sept8) as a candidate for UPE. Sept8/SEPTIN8 expression increased in HS rats with elevated UPE and tubulointerstitial injury and in the in vitro hypoxia model. SEPTIN8 is detected within proximal tubule cells in human kidney samples and localizes with acetyl-alpha tubulin in the culture system. After hypoxia, SEPTIN8 staining becomes diffuse and appears to relocalize with actin. These data suggest a role of SEPTIN8 in cellular organization and structure in response to environmental stress. This study demonstrates that integration of a rat genetic model with an environmentally induced tubule damage system identifies Sept8/SEPTIN8 and informs novel aspects of the complex gene by environmental interactions contributing to CKD risk.

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A Variant Noncoding Region Regulates Prrx1 and Predisposes to Atrial Arrhythmias

Circulation Research ◽

10.1161/circresaha.121.319146 ◽

2021 ◽

Author(s):

Fernanda M Bosada ◽

Mathilde R Rivaud ◽

Jae-Sun Uhm ◽

Sander Verheule ◽

Karel van Duijvenboden ◽

...

Keyword(s):

Sodium Current ◽

Association Studies ◽

Noncoding Region ◽

Specific Gene ◽

Genome Wide Association Studies ◽

Enhancer Activity ◽

Atrial Cardiomyocytes ◽

The Impact ◽

Lineage Specific Gene

Rationale: Atrial Fibrillation (AF) is the most common cardiac arrhythmia diagnosed in clinical practice. Genome-wide association studies have identified AF-associated common variants across 100+ genomic loci, but the mechanism underlying the impact of these variant loci on AF susceptibility in vivo has remained largely undefined. One such variant region, highly associated with AF, is found at 1q24, close to PRRX1, encoding the Paired Related Homeobox 1 transcription factor. Objective: To identify the mechanistic link between the variant region at 1q24 and AF predisposition. Methods and Results: The mouse orthologue of the noncoding variant genomic region (R1A) at 1q24 was deleted using CRISPR genome editing. Among the genes sharing the topologically associated domain with the deleted R1A region (Kifap3, Prrx1, Fmo2, Prrc2c), only the broadly expressed gene Prrx1 was downregulated in mutants, and only in cardiomyocytes. Expression and epigenetic profiling revealed that a cardiomyocyte lineage-specific gene program (Mhrt, Myh6, Rbm20, Tnnt2, Ttn, Ckm) was upregulated in R1A-/- atrial cardiomyocytes, and that Mef2 binding motifs were significantly enriched at differentially accessible chromatin sites. Consistently, Prrx1 suppressed Mef2-activated enhancer activity in HL-1 cells. Mice heterozygous or homozygous for the R1A deletion were susceptible to atrial arrhythmia induction, had atrial conduction slowing and more irregular RR intervals. Isolated R1A-/- mouse left atrial cardiomyocytes showed lower action potential upstroke velocities and sodium current, as well as increased systolic and diastolic calcium concentrations compared to controls. Conclusions: The noncoding AF variant region at 1q24 modulates Prrx1 expression in cardiomyocytes. Cardiomyocyte-specific reduction of Prrx1 expression upon deletion of the noncoding region leads to a profound induction of a cardiac lineage-specific gene program and to propensity for AF. These data indicate that AF-associated variants in humans may exert AF predisposition through reduced PRRX1 expression in cardiomyocytes.

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Combined knockout of Lrrk2 and Rab29 does not result in behavioral abnormalities in vivo

10.1101/2020.05.13.093708 ◽

2020 ◽

Cited By ~ 2

Author(s):

Melissa Conti Mazza ◽

Victoria Nguyen ◽

Alexandra Beilina ◽

Jinhui Ding ◽

Mark R. Cookson

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Kinase Activity ◽

Association Studies ◽

Dopamine Neurons ◽

Substantia Nigra Pars Compacta ◽

Genome Wide Association Studies ◽

Double Knockout ◽

Knockout Mouse Model

AbstractCoding mutations in the LRRK2 gene, encoding for a large protein kinase, have been shown to cause familial Parkinson’s disease (PD). The immediate biological consequence of LRRK2 mutations is to increase kinase activity, leading to the suggestion that inhibition of this enzyme might be useful therapeutically to slow disease progression. Genome-wide association studies have identified the chromosomal loci around LRRK2 and one of its proposed substrates, RAB29, as contributors towards the lifetime risk of sporadic PD. Considering the evidence for interactions between LRRK2 and RAB29 on the genetic and protein levels, here we generated a double knockout mouse model and determined whether there are any consequences on brain function with aging. From a battery of motor and non-motor behavioral tests, we noted only that 18-24 month Rab29-/- and double (Lrrk2-/-/Rab29-/-) knockout mice had diminished locomotor behavior in open field compared to wildtype mice. However, no genotype differences were seen in number of substantia nigra pars compacta (SNc) dopamine neurons or in tyrosine hydroxylase levels in the SNc and striatum, which might reflect a PD-like pathology. These results suggest that depletion of both Lrrk2 and Rab29 is tolerated, at least in mice, and support that this pathway might be able to be safely targeted for therapeutics in humans.Significance statementGenetic variation in LRRK2 that result in elevated kinase activity can cause Parkinson’s disease (PD), suggesting LRRK2 inhibition as a therapeutic strategy. RAB29, a substrate of LRRK2, has also been associated with increased PD risk. Evidence exists for an interactive relationship between LRRK2 and RAB29. Mouse models lacking either LRRK2 or RAB29 do not show brain pathologies. We hypothesized that the loss of both targets would result in additive effects across in vivo and post-mortem assessments in aging mice. We found that loss of both LRRK2 and RAB29 did not result in significant behavioral deficits or dopamine neuron loss. This evidence suggests that chronic inhibition of this pathway should be tolerated clinically.

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Gene4PD: A Comprehensive Genetic Database of Parkinson’s Disease

Frontiers in Neuroscience ◽

10.3389/fnins.2021.679568 ◽

2021 ◽

Vol 15 ◽

Author(s):

Bin Li ◽

Guihu Zhao ◽

Qiao Zhou ◽

Yali Xie ◽

Zheng Wang ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Neurodegenerative Disorder ◽

Late Onset ◽

Association Studies ◽

Age At Onset ◽

Genetic Data ◽

Genome Wide Association Studies ◽

Onset Age ◽

Loss Of Function

Parkinson’s disease (PD) is a complex neurodegenerative disorder with a strong genetic component. A growing number of variants and genes have been reported to be associated with PD; however, there is no database that integrate different type of genetic data, and support analyzing of PD-associated genes (PAGs). By systematic review and curation of multiple lines of public studies, we integrate multiple layers of genetic data (rare variants and copy-number variants identified from patients with PD, associated variants identified from genome-wide association studies, differentially expressed genes, and differential DNA methylation genes) and age at onset in PD. We integrated five layers of genetic data (8302 terms) with different levels of evidences from more than 3,000 studies and prioritized 124 PAGs with strong or suggestive evidences. These PAGs were identified to be significantly interacted with each other and formed an interconnected functional network enriched in several functional pathways involved in PD, suggesting these genes may contribute to the pathogenesis of PD. Furthermore, we identified 10 genes were associated with a juvenile-onset (age ≤ 30 years), 11 genes were associated with an early-onset (age of 30–50 years), whereas another 10 genes were associated with a late-onset (age > 50 years). Notably, the AAOs of patients with loss of function variants in five genes were significantly lower than that of patients with deleterious missense variants, while patients with VPS13C (P = 0.01) was opposite. Finally, we developed an online database named Gene4PD (http://genemed.tech/gene4pd) which integrated published genetic data in PD, the PAGs, and 63 popular genomic data sources, as well as an online pipeline for prioritize risk variants in PD. In conclusion, Gene4PD provides researchers and clinicians comprehensive genetic knowledge and analytic platform for PD, and would also improve the understanding of pathogenesis in PD.

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