1
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Mishra A, Jajodia A, Weston E, Jayavelu ND, Garcia M, Hossack D, Hawkins RD. Identification of functional enhancer variants associated with type I diabetes in CD4+ T cells. Front Immunol 2024; 15:1387253. [PMID: 38947339 PMCID: PMC11211866 DOI: 10.3389/fimmu.2024.1387253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Accepted: 04/09/2024] [Indexed: 07/02/2024] Open
Abstract
Type I diabetes is an autoimmune disease mediated by T-cell destruction of β cells in pancreatic islets. Currently, there is no known cure, and treatment consists of daily insulin injections. Genome-wide association studies and twin studies have indicated a strong genetic heritability for type I diabetes and implicated several genes. As most strongly associated variants are noncoding, there is still a lack of identification of functional and, therefore, likely causal variants. Given that many of these genetic variants reside in enhancer elements, we have tested 121 CD4+ T-cell enhancer variants associated with T1D. We found four to be functional through massively parallel reporter assays. Three of the enhancer variants weaken activity, while the fourth strengthens activity. We link these to their cognate genes using 3D genome architecture or eQTL data and validate them using CRISPR editing. Validated target genes include CLEC16A and SOCS1. While these genes have been previously implicated in type 1 diabetes and other autoimmune diseases, we show that enhancers controlling their expression harbor functional variants. These variants, therefore, may act as causal type 1 diabetic variants.
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Affiliation(s)
- Arpit Mishra
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States
| | - Ajay Jajodia
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States
| | - Eryn Weston
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States
| | - Naresh Doni Jayavelu
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States
| | - Mariana Garcia
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States
| | - Daniel Hossack
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States
| | - R. David Hawkins
- Division of Medical Genetics, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States
- Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine, Seattle, WA, United States
- Benaroya Research Institute at Virginia Mason, Seattle, WA, United States
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2
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Stankey CT, Bourges C, Haag LM, Turner-Stokes T, Piedade AP, Palmer-Jones C, Papa I, Silva Dos Santos M, Zhang Q, Cameron AJ, Legrini A, Zhang T, Wood CS, New FN, Randzavola LO, Speidel L, Brown AC, Hall A, Saffioti F, Parkes EC, Edwards W, Direskeneli H, Grayson PC, Jiang L, Merkel PA, Saruhan-Direskeneli G, Sawalha AH, Tombetti E, Quaglia A, Thorburn D, Knight JC, Rochford AP, Murray CD, Divakar P, Green M, Nye E, MacRae JI, Jamieson NB, Skoglund P, Cader MZ, Wallace C, Thomas DC, Lee JC. A disease-associated gene desert directs macrophage inflammation through ETS2. Nature 2024; 630:447-456. [PMID: 38839969 PMCID: PMC11168933 DOI: 10.1038/s41586-024-07501-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 05/01/2024] [Indexed: 06/07/2024]
Abstract
Increasing rates of autoimmune and inflammatory disease present a burgeoning threat to human health1. This is compounded by the limited efficacy of available treatments1 and high failure rates during drug development2, highlighting an urgent need to better understand disease mechanisms. Here we show how functional genomics could address this challenge. By investigating an intergenic haplotype on chr21q22-which has been independently linked to inflammatory bowel disease, ankylosing spondylitis, primary sclerosing cholangitis and Takayasu's arteritis3-6-we identify that the causal gene, ETS2, is a central regulator of human inflammatory macrophages and delineate the shared disease mechanism that amplifies ETS2 expression. Genes regulated by ETS2 were prominently expressed in diseased tissues and more enriched for inflammatory bowel disease GWAS hits than most previously described pathways. Overexpressing ETS2 in resting macrophages reproduced the inflammatory state observed in chr21q22-associated diseases, with upregulation of multiple drug targets, including TNF and IL-23. Using a database of cellular signatures7, we identified drugs that might modulate this pathway and validated the potent anti-inflammatory activity of one class of small molecules in vitro and ex vivo. Together, this illustrates the power of functional genomics, applied directly in primary human cells, to identify immune-mediated disease mechanisms and potential therapeutic opportunities.
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Affiliation(s)
- C T Stankey
- Genetic Mechanisms of Disease Laboratory, The Francis Crick Institute, London, UK
- Department of Immunology and Inflammation, Imperial College London, London, UK
- Washington University School of Medicine, St Louis, MO, USA
| | - C Bourges
- Genetic Mechanisms of Disease Laboratory, The Francis Crick Institute, London, UK
| | - L M Haag
- Division of Gastroenterology, Infectious Diseases and Rheumatology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - T Turner-Stokes
- Genetic Mechanisms of Disease Laboratory, The Francis Crick Institute, London, UK
- Department of Immunology and Inflammation, Imperial College London, London, UK
| | - A P Piedade
- Genetic Mechanisms of Disease Laboratory, The Francis Crick Institute, London, UK
| | - C Palmer-Jones
- Department of Gastroenterology, Royal Free Hospital, London, UK
- Institute for Liver and Digestive Health, Division of Medicine, University College London, London, UK
| | - I Papa
- Genetic Mechanisms of Disease Laboratory, The Francis Crick Institute, London, UK
| | | | - Q Zhang
- Genomics of Inflammation and Immunity Group, Human Genetics Programme, Wellcome Sanger Institute, Hinxton, UK
| | - A J Cameron
- Wolfson Wohl Cancer Centre, School of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - A Legrini
- Wolfson Wohl Cancer Centre, School of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - T Zhang
- Wolfson Wohl Cancer Centre, School of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - C S Wood
- Wolfson Wohl Cancer Centre, School of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - F N New
- NanoString Technologies, Seattle, WA, USA
| | - L O Randzavola
- Department of Immunology and Inflammation, Imperial College London, London, UK
| | - L Speidel
- Ancient Genomics Laboratory, The Francis Crick Institute, London, UK
- Genetics Institute, University College London, London, UK
| | - A C Brown
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - A Hall
- The Sheila Sherlock Liver Centre, Royal Free Hospital, London, UK
- Department of Cellular Pathology, Royal Free Hospital, London, UK
| | - F Saffioti
- Institute for Liver and Digestive Health, Division of Medicine, University College London, London, UK
- The Sheila Sherlock Liver Centre, Royal Free Hospital, London, UK
| | - E C Parkes
- Genetic Mechanisms of Disease Laboratory, The Francis Crick Institute, London, UK
| | - W Edwards
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge, Cambridge, UK
| | - H Direskeneli
- Department of Internal Medicine, Division of Rheumatology, Marmara University, Istanbul, Turkey
| | - P C Grayson
- Systemic Autoimmunity Branch, NIAMS, National Institutes of Health, Bethesda, MD, USA
| | - L Jiang
- Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - P A Merkel
- Division of Rheumatology, Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Epidemiology, Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, PA, USA
| | - G Saruhan-Direskeneli
- Department of Physiology, Istanbul University, Istanbul Faculty of Medicine, Istanbul, Turkey
| | - A H Sawalha
- Division of Rheumatology, Department of Pediatrics, University of Pittsburgh, Pittsburgh, PA, USA
- Division of Rheumatology and Clinical Immunology, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Lupus Center of Excellence, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - E Tombetti
- Department of Biomedical and Clinical Sciences, Milan University, Milan, Italy
- Internal Medicine and Rheumatology, ASST FBF-Sacco, Milan, Italy
| | - A Quaglia
- Department of Cellular Pathology, Royal Free Hospital, London, UK
- UCL Cancer Institute, London, UK
| | - D Thorburn
- Institute for Liver and Digestive Health, Division of Medicine, University College London, London, UK
- The Sheila Sherlock Liver Centre, Royal Free Hospital, London, UK
| | - J C Knight
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
- Chinese Academy of Medical Sciences Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- NIHR Comprehensive Biomedical Research Centre, Oxford, UK
| | - A P Rochford
- Department of Gastroenterology, Royal Free Hospital, London, UK
- Institute for Liver and Digestive Health, Division of Medicine, University College London, London, UK
| | - C D Murray
- Department of Gastroenterology, Royal Free Hospital, London, UK
- Institute for Liver and Digestive Health, Division of Medicine, University College London, London, UK
| | - P Divakar
- NanoString Technologies, Seattle, WA, USA
| | - M Green
- Experimental Histopathology STP, The Francis Crick Institute, London, UK
| | - E Nye
- Experimental Histopathology STP, The Francis Crick Institute, London, UK
| | - J I MacRae
- Metabolomics STP, The Francis Crick Institute, London, UK
| | - N B Jamieson
- Wolfson Wohl Cancer Centre, School of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - P Skoglund
- Ancient Genomics Laboratory, The Francis Crick Institute, London, UK
| | - M Z Cader
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - C Wallace
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge, Cambridge, UK
- MRC Biostatistics Unit, Cambridge Institute of Public Health, Cambridge, UK
| | - D C Thomas
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - J C Lee
- Genetic Mechanisms of Disease Laboratory, The Francis Crick Institute, London, UK.
- Department of Gastroenterology, Royal Free Hospital, London, UK.
- Institute for Liver and Digestive Health, Division of Medicine, University College London, London, UK.
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Oliveros W, Delfosse K, Lato DF, Kiriakopulos K, Mokhtaridoost M, Said A, McMurray BJ, Browning JW, Mattioli K, Meng G, Ellis J, Mital S, Melé M, Maass PG. Systematic characterization of regulatory variants of blood pressure genes. CELL GENOMICS 2023; 3:100330. [PMID: 37492106 PMCID: PMC10363820 DOI: 10.1016/j.xgen.2023.100330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 03/29/2023] [Accepted: 04/28/2023] [Indexed: 07/27/2023]
Abstract
High blood pressure (BP) is the major risk factor for cardiovascular disease. Genome-wide association studies have identified genetic variants for BP, but functional insights into causality and related molecular mechanisms lag behind. We functionally characterize 4,608 genetic variants in linkage with 135 BP loci in vascular smooth muscle cells and cardiomyocytes by massively parallel reporter assays. High densities of regulatory variants at BP loci (i.e., ULK4, MAP4, CFDP1, PDE5A) indicate that multiple variants drive genetic association. Regulatory variants are enriched in repeats, alter cardiovascular-related transcription factor motifs, and spatially converge with genes controlling specific cardiovascular pathways. Using heuristic scoring, we define likely causal variants, and CRISPR prime editing finally determines causal variants for KCNK9, SFXN2, and PCGF6, which are candidates for developing high BP. Our systems-level approach provides a catalog of functionally relevant variants and their genomic architecture in two trait-relevant cell lines for a better understanding of BP gene regulation.
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Affiliation(s)
- Winona Oliveros
- Life Sciences Department, Barcelona Supercomputing Center, 08034 Barcelona, Catalonia, Spain
| | - Kate Delfosse
- Genetics & Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Daniella F. Lato
- Genetics & Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Katerina Kiriakopulos
- Genetics & Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Milad Mokhtaridoost
- Genetics & Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Abdelrahman Said
- Genetics & Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Brandon J. McMurray
- Genetics & Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Jared W.L. Browning
- Genetics & Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Kaia Mattioli
- Division of Genetics, Department of Medicine, Brigham & Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Guoliang Meng
- Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - James Ellis
- Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Seema Mital
- Genetics & Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
- Ted Rogers Centre for Heart Research, Toronto, ON M5G 1X8, Canada
- Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Marta Melé
- Life Sciences Department, Barcelona Supercomputing Center, 08034 Barcelona, Catalonia, Spain
| | - Philipp G. Maass
- Genetics & Genome Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
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Guga S, Wang Y, Graham DC, Vyse TJ. A review of genetic risk in systemic lupus erythematosus. Expert Rev Clin Immunol 2023; 19:1247-1258. [PMID: 37496418 DOI: 10.1080/1744666x.2023.2240959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 05/10/2023] [Indexed: 07/28/2023]
Abstract
INTRODUCTION Systemic Lupus Erythematosus (SLE) is a complex multisystem autoimmune disease with a wide range of signs and symptoms in affected individuals. The utilization of genome-wide association study (GWAS) technology has led to an explosion in the number of genetic risk factors mapped for autoimmune diseases, including SLE. AREAS COVERED In this review, we summarize the more recent genetic risk loci mapped in SLE, which bring the total number of loci mapped to approximately 200. We review prioritization analyses of the associated variants and experimental validation of the putative causal variants. This includes the implementation of new bioinformatic techniques to align genomic and functional data and the use of transcriptomics with single-cell RNA-sequencing, CRISPR genome editing, and Massive Parallel Reporter Assays to analyze non-coding regulatory genetics. EXPERT OPINION Despite progress in identifying more genetic risk loci and variant-gene pairs for SLE, understanding its pathogenesis and applying findings clinically remains challenging. The polygenic risk score (PRS) has been used as an application of SLE genetics, but with limited performance in non-EUR populations. In the next few years, advancements in proteomics, post-translational modification estimation, and whole-genome sequencing will enhance disease understanding.
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Affiliation(s)
- Suri Guga
- Department of Medical & Molecular Genetics, King's College London, London, UK
| | - Yuxuan Wang
- Department of Medical & Molecular Genetics, King's College London, London, UK
| | | | - Timothy J Vyse
- Department of Medical & Molecular Genetics, King's College London, London, UK
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5
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Qiu Y, Feng D, Jiang W, Zhang T, Lu Q, Zhao M. 3D genome organization and epigenetic regulation in autoimmune diseases. Front Immunol 2023; 14:1196123. [PMID: 37346038 PMCID: PMC10279977 DOI: 10.3389/fimmu.2023.1196123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/17/2023] [Indexed: 06/23/2023] Open
Abstract
Three-dimensional (3D) genomics is an emerging field of research that investigates the relationship between gene regulatory function and the spatial structure of chromatin. Chromatin folding can be studied using chromosome conformation capture (3C) technology and 3C-based derivative sequencing technologies, including chromosome conformation capture-on-chip (4C), chromosome conformation capture carbon copy (5C), and high-throughput chromosome conformation capture (Hi-C), which allow scientists to capture 3D conformations from a single site to the entire genome. A comprehensive analysis of the relationships between various regulatory components and gene function also requires the integration of multi-omics data such as genomics, transcriptomics, and epigenomics. 3D genome folding is involved in immune cell differentiation, activation, and dysfunction and participates in a wide range of diseases, including autoimmune diseases. We describe hierarchical 3D chromatin organization in this review and conclude with characteristics of C-techniques and multi-omics applications of the 3D genome. In addition, we describe the relationship between 3D genome structure and the differentiation and maturation of immune cells and address how changes in chromosome folding contribute to autoimmune diseases.
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Affiliation(s)
- Yueqi Qiu
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
- Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences, Nanjing, China
| | - Delong Feng
- Department of Dermatology, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Wenjuan Jiang
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
- Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences, Nanjing, China
| | - Tingting Zhang
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
- Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences, Nanjing, China
- State Key Laboratory of Natural Medicines, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Qianjin Lu
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
- Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences, Nanjing, China
- Department of Dermatology, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Ming Zhao
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
- Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences, Nanjing, China
- Department of Dermatology, The Second Xiangya Hospital of Central South University, Changsha, China
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6
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Stefan K, Barski A. Cis-regulatory atlas of primary human CD4+ T cells. BMC Genomics 2023; 24:253. [PMID: 37170195 PMCID: PMC10173520 DOI: 10.1186/s12864-023-09288-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 03/31/2023] [Indexed: 05/13/2023] Open
Abstract
Cis-regulatory elements (CRE) are critical for coordinating gene expression programs that dictate cell-specific differentiation and homeostasis. Recently developed self-transcribing active regulatory region sequencing (STARR-Seq) has allowed for genome-wide annotation of functional CREs. Despite this, STARR-Seq assays are only employed in cell lines, in part, due to difficulties in delivering reporter constructs. Herein, we implemented and validated a STARR-Seq-based screen in human CD4+ T cells using a non-integrating lentiviral transduction system. Lenti-STARR-Seq is the first example of a genome-wide assay of CRE function in human primary cells, identifying thousands of functional enhancers and negative regulatory elements (NREs) in human CD4+ T cells. We find an unexpected difference in nucleosome organization between enhancers and NRE: enhancers are located between nucleosomes, whereas NRE are occupied by nucleosomes in their endogenous locations. We also describe chromatin modification, eRNA production, and transcription factor binding at both enhancers and NREs. Our findings support the idea of silencer repurposing as enhancers in alternate cell types. Collectively, these data suggest that Lenti-STARR-Seq is a successful approach for CRE screening in primary human cell types, and provides an atlas of functional CREs in human CD4+ T cells.
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Affiliation(s)
- Kurtis Stefan
- Division of Allergy & Immunology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, MLC 7028, Cincinnati, OH, 45229-3026, USA
- Medical Scientist Training Program (MSTP), University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
| | - Artem Barski
- Division of Allergy & Immunology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, MLC 7028, Cincinnati, OH, 45229-3026, USA.
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229-3026, USA.
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA.
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Richard D, Capellini TD, Diekman BO. Epigenetics as a mediator of genetic risk in osteoarthritis: role during development, homeostasis, aging, and disease progression. Am J Physiol Cell Physiol 2023; 324:C1078-C1088. [PMID: 36971423 PMCID: PMC10191130 DOI: 10.1152/ajpcell.00574.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/16/2023] [Accepted: 03/16/2023] [Indexed: 03/29/2023]
Abstract
The identification of genomic loci that are associated with osteoarthritis (OA) has provided a starting point for understanding how genetic variation activates catabolic processes in the joint. However, genetic variants can only alter gene expression and cellular function when the epigenetic environment is permissive to these effects. In this review, we provide examples of how epigenetic shifts at distinct life stages can alter the risk for OA, which we posit is critical for the proper interpretation of genome-wide association studies (GWAS). During development, intensive work on the growth and differentiation factor 5 (GDF5) locus has revealed the importance of tissue-specific enhancer activity in controlling both joint development and the subsequent risk for OA. During homeostasis in adults, underlying genetic risk factors may help establish beneficial or catabolic "set points" that dictate tissue function, with a strong cumulative effect on OA risk. During aging, methylation changes and the reorganization of chromatin can "unmask" the effects of genetic variants. The destructive function of variants that alter aging would only mediate effects after reproductive competence and thus avoid any evolutionary selection pressure, as consistent with larger frameworks of biological aging and its relationship to disease. A similar "unmasking" may occur during OA progression, which is supported by the finding of distinct expression quantitative trait loci (eQTLs) in chondrocytes depending on the degree of tissue degradation. Finally, we propose that massively parallel reporter assays (MPRAs) will be a valuable tool to test the function of putative OA GWAS variants in chondrocytes from different life stages.
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Affiliation(s)
- Daniel Richard
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States
| | - Terence D Capellini
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States
| | - Brian O Diekman
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, and North Carolina State University, Raleigh, North Carolina, United States
- Thurston Arthritis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States
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8
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Gundry M, Sankaran VG. Hacking hematopoiesis - emerging tools for examining variant effects. Dis Model Mech 2023; 16:288409. [PMID: 36826849 PMCID: PMC9983777 DOI: 10.1242/dmm.049857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
Hematopoiesis is a continuous process of blood and immune cell production. It is orchestrated by thousands of gene products that respond to extracellular signals by guiding cell fate decisions to meet the needs of the organism. Although much of our knowledge of this process comes from work in model systems, we have learned a great deal from studies on human genetic variation. Considerable insight has emerged from studies on presumed monogenic blood disorders, which continue to provide key insights into the mechanisms critical for hematopoiesis. Furthermore, the emergence of large-scale biobanks and cohorts has uncovered thousands of genomic loci associated with blood cell traits and diseases. Some of these blood cell trait-associated loci act as modifiers of what were once thought to be monogenic blood diseases. However, most of these loci await functional validation. Here, we discuss the validation bottleneck and emerging methods to more effectively connect variant to function. In particular, we highlight recent innovations in genome editing, which have paved the path forward for high-throughput functional assessment of loci. Finally, we discuss existing barriers to progress, including challenges in manipulating the genomes of primary hematopoietic cells.
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Affiliation(s)
- Michael Gundry
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Vijay G. Sankaran
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Author for correspondence ()
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9
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Stankey CT, Lee JC. Translating non-coding genetic associations into a better understanding of immune-mediated disease. Dis Model Mech 2023; 16:297044. [PMID: 36897113 PMCID: PMC10040244 DOI: 10.1242/dmm.049790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023] Open
Abstract
Genome-wide association studies have identified hundreds of genetic loci that are associated with immune-mediated diseases. Most disease-associated variants are non-coding, and a large proportion of these variants lie within enhancers. As a result, there is a pressing need to understand how common genetic variation might affect enhancer function and thereby contribute to immune-mediated (and other) diseases. In this Review, we first describe statistical and experimental methods to identify causal genetic variants that modulate gene expression, including statistical fine-mapping and massively parallel reporter assays. We then discuss approaches to characterise the mechanisms by which these variants modulate immune function, such as clustered regularly interspaced short palindromic repeats (CRISPR)-based screens. We highlight examples of studies that, by elucidating the effects of disease variants within enhancers, have provided important insights into immune function and uncovered key pathways of disease.
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Affiliation(s)
- Christina T Stankey
- Genetic Mechanisms of Disease Laboratory, The Francis Crick Institute, London NW1 1AT, UK
- Department of Immunology and Inflammation, Imperial College London, London W12 0NN, UK
| | - James C Lee
- Genetic Mechanisms of Disease Laboratory, The Francis Crick Institute, London NW1 1AT, UK
- Institute of Liver and Digestive Health, Royal Free Hospital, University College London, London NW3 2PF, UK
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10
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Wang S, Sun ST, Zhang XY, Ding HR, Yuan Y, He JJ, Wang MS, Yang B, Li YB. The Evolution of Single-Cell RNA Sequencing Technology and Application: Progress and Perspectives. Int J Mol Sci 2023; 24:ijms24032943. [PMID: 36769267 PMCID: PMC9918030 DOI: 10.3390/ijms24032943] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 01/01/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
As an emerging sequencing technology, single-cell RNA sequencing (scRNA-Seq) has become a powerful tool for describing cell subpopulation classification and cell heterogeneity by achieving high-throughput and multidimensional analysis of individual cells and circumventing the shortcomings of traditional sequencing for detecting the average transcript level of cell populations. It has been applied to life science and medicine research fields such as tracking dynamic cell differentiation, revealing sensitive effector cells, and key molecular events of diseases. This review focuses on the recent technological innovations in scRNA-Seq, highlighting the latest research results with scRNA-Seq as the core technology in frontier research areas such as embryology, histology, oncology, and immunology. In addition, this review outlines the prospects for its innovative application in traditional Chinese medicine (TCM) research and discusses the key issues currently being addressed by scRNA-Seq and its great potential for exploring disease diagnostic targets and uncovering drug therapeutic targets in combination with multiomics technologies.
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Affiliation(s)
| | | | | | | | | | | | | | - Bin Yang
- Correspondence: (B.Y.); (Y.-B.L.)
| | - Yu-Bo Li
- Correspondence: (B.Y.); (Y.-B.L.)
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11
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Stikker BS, Hendriks RW, Stadhouders R. Decoding the genetic and epigenetic basis of asthma. Allergy 2023; 78:940-956. [PMID: 36727912 DOI: 10.1111/all.15666] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/17/2023] [Accepted: 01/30/2023] [Indexed: 02/03/2023]
Abstract
Asthma is a complex and heterogeneous chronic inflammatory disease of the airways. Alongside environmental factors, asthma susceptibility is strongly influenced by genetics. Given its high prevalence and our incomplete understanding of the mechanisms underlying disease susceptibility, asthma is frequently studied in genome-wide association studies (GWAS), which have identified thousands of genetic variants associated with asthma development. Virtually all these genetic variants reside in non-coding genomic regions, which has obscured the functional impact of asthma-associated variants and their translation into disease-relevant mechanisms. Recent advances in genomics technology and epigenetics now offer methods to link genetic variants to gene regulatory elements embedded within non-coding regions, which have started to unravel the molecular mechanisms underlying the complex (epi)genetics of asthma. Here, we provide an integrated overview of (epi)genetic variants associated with asthma, focusing on efforts to link these disease associations to biological insight into asthma pathophysiology using state-of-the-art genomics methodology. Finally, we provide a perspective as to how decoding the genetic and epigenetic basis of asthma has the potential to transform clinical management of asthma and to predict the risk of asthma development.
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Affiliation(s)
- Bernard S Stikker
- Department of Pulmonary Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Ralph Stadhouders
- Department of Pulmonary Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.,Department of Cell Biology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
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12
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Current challenges in understanding the role of enhancers in disease. Nat Struct Mol Biol 2022; 29:1148-1158. [PMID: 36482255 DOI: 10.1038/s41594-022-00896-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/04/2022] [Indexed: 12/13/2022]
Abstract
Enhancers play a central role in the spatiotemporal control of gene expression and tend to work in a cell-type-specific manner. In addition, they are suggested to be major contributors to phenotypic variation, evolution and disease. There is growing evidence that enhancer dysfunction due to genetic, structural or epigenetic mechanisms contributes to a broad range of human diseases referred to as enhanceropathies. Such mechanisms often underlie the susceptibility to common diseases, but can also play a direct causal role in cancer or Mendelian diseases. Despite the recent gain of insights into enhancer biology and function, we still have a limited ability to predict how enhancer dysfunction impacts gene expression. Here we discuss the major challenges that need to be overcome when studying the role of enhancers in disease etiology and highlight opportunities and directions for future studies, aiming to disentangle the molecular basis of enhanceropathies.
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13
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Cuartero S, Stik G, Stadhouders R. Three-dimensional genome organization in immune cell fate and function. Nat Rev Immunol 2022; 23:206-221. [PMID: 36127477 DOI: 10.1038/s41577-022-00774-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2022] [Indexed: 11/09/2022]
Abstract
Immune cell development and activation demand the precise and coordinated control of transcriptional programmes. Three-dimensional (3D) organization of the genome has emerged as an important regulator of chromatin state, transcriptional activity and cell identity by facilitating or impeding long-range genomic interactions among regulatory elements and genes. Chromatin folding thus enables cell type-specific and stimulus-specific transcriptional responses to extracellular signals, which are essential for the control of immune cell fate, for inflammatory responses and for generating a diverse repertoire of antigen receptor specificities. Here, we review recent findings connecting 3D genome organization to the control of immune cell differentiation and function, and discuss how alterations in genome folding may lead to immune dysfunction and malignancy.
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Affiliation(s)
- Sergi Cuartero
- Josep Carreras Leukaemia Research Institute (IJC), Badalona, Spain. .,Germans Trias i Pujol Research Institute (IGTP), Badalona, Spain.
| | - Grégoire Stik
- Centre for Genomic Regulation (CRG), Institute of Science and Technology (BIST), Barcelona, Spain. .,Universitat Pompeu Fabra (UPF), Barcelona, Spain.
| | - Ralph Stadhouders
- Department of Pulmonary Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands. .,Department of Cell Biology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.
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14
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Zhao Y, Vartak SV, Conte A, Wang X, Garcia DA, Stevens E, Kyoung Jung S, Kieffer-Kwon KR, Vian L, Stodola T, Moris F, Chopp L, Preite S, Schwartzberg PL, Kulinski JM, Olivera A, Harly C, Bhandoola A, Heuston EF, Bodine DM, Urrutia R, Upadhyaya A, Weirauch MT, Hager G, Casellas R. "Stripe" transcription factors provide accessibility to co-binding partners in mammalian genomes. Mol Cell 2022; 82:3398-3411.e11. [PMID: 35863348 PMCID: PMC9481673 DOI: 10.1016/j.molcel.2022.06.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 04/06/2022] [Accepted: 06/22/2022] [Indexed: 10/17/2022]
Abstract
Regulatory elements activate promoters by recruiting transcription factors (TFs) to specific motifs. Notably, TF-DNA interactions often depend on cooperativity with colocalized partners, suggesting an underlying cis-regulatory syntax. To explore TF cooperativity in mammals, we analyze ∼500 mouse and human primary cells by combining an atlas of TF motifs, footprints, ChIP-seq, transcriptomes, and accessibility. We uncover two TF groups that colocalize with most expressed factors, forming stripes in hierarchical clustering maps. The first group includes lineage-determining factors that occupy DNA elements broadly, consistent with their key role in tissue-specific transcription. The second one, dubbed universal stripe factors (USFs), comprises ∼30 SP, KLF, EGR, and ZBTB family members that recognize overlapping GC-rich sequences in all tissues analyzed. Knockouts and single-molecule tracking reveal that USFs impart accessibility to colocalized partners and increase their residence time. Mammalian cells have thus evolved a TF superfamily with overlapping DNA binding that facilitate chromatin accessibility.
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Affiliation(s)
- Yongbing Zhao
- The NIH Regulome Project, National Institutes of Health, Bethesda, MD 20892, USA; Lymphocyte Nuclear Biology, NIAMS-NCI, NIH, Bethesda, MD 20892, USA.
| | - Supriya V Vartak
- The NIH Regulome Project, National Institutes of Health, Bethesda, MD 20892, USA; Lymphocyte Nuclear Biology, NIAMS-NCI, NIH, Bethesda, MD 20892, USA
| | - Andrea Conte
- The NIH Regulome Project, National Institutes of Health, Bethesda, MD 20892, USA; Lymphocyte Nuclear Biology, NIAMS-NCI, NIH, Bethesda, MD 20892, USA
| | - Xiang Wang
- The NIH Regulome Project, National Institutes of Health, Bethesda, MD 20892, USA; Lymphocyte Nuclear Biology, NIAMS-NCI, NIH, Bethesda, MD 20892, USA
| | - David A Garcia
- Laboratory of Receptor Biology and Gene Expression, NCI, NIH, Bethesda, MD 20893, USA; Department of Physics, University of Maryland, College Park, MD 20742, USA
| | - Evan Stevens
- Lymphocyte Nuclear Biology, NIAMS-NCI, NIH, Bethesda, MD 20892, USA
| | - Seol Kyoung Jung
- The NIH Regulome Project, National Institutes of Health, Bethesda, MD 20892, USA; Lymphocyte Nuclear Biology, NIAMS-NCI, NIH, Bethesda, MD 20892, USA
| | | | - Laura Vian
- Lymphocyte Nuclear Biology, NIAMS-NCI, NIH, Bethesda, MD 20892, USA
| | - Timothy Stodola
- Genomic Sciences and Precision Medicine Center (GSPMC), Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Francisco Moris
- EntreChem S.L., Vivero Ciencias de la Salud, 33011 Oviedo, Spain
| | - Laura Chopp
- Laboratory of Immune Cell Biology, NCI, NIH, Bethesda, MD 20892, USA
| | - Silvia Preite
- Laboratory of Immune System Biology, NIAID, NIH, Bethesda, MD 20892, USA
| | | | - Joseph M Kulinski
- Mast cell Biology Section, Laboratory of Allergic Diseases, NIAID, NIH, Bethesda, MD 20892, USA
| | - Ana Olivera
- Mast cell Biology Section, Laboratory of Allergic Diseases, NIAID, NIH, Bethesda, MD 20892, USA
| | - Christelle Harly
- Laboratory of Genome Integrity, NCI, NIH, Bethesda, MD 20892, USA
| | | | | | - David M Bodine
- Genetics and Molecular Biology Branch, NHGRI, NIH, Bethesda, MD 20892, USA
| | - Raul Urrutia
- Genomic Sciences and Precision Medicine Center (GSPMC), Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Arpita Upadhyaya
- Department of Physics, University of Maryland, College Park, MD 20742, USA
| | - Matthew T Weirauch
- Divisions of Biomedical Informatics and Developmental Biology, Center for Autoimmune Genomics and Etiology (CAGE), Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Gordon Hager
- Laboratory of Receptor Biology and Gene Expression, NCI, NIH, Bethesda, MD 20893, USA
| | - Rafael Casellas
- The NIH Regulome Project, National Institutes of Health, Bethesda, MD 20892, USA; Lymphocyte Nuclear Biology, NIAMS-NCI, NIH, Bethesda, MD 20892, USA.
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15
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Perez-Sanchez C, Barbera Betancourt A, Lyons PA, Zhang Z, Suo C, Lee JC, McKinney EF, Modis LK, Ellson C, Smith KG. miR-374a-5p regulates inflammatory genes and monocyte function in patients with inflammatory bowel disease. J Exp Med 2022; 219:e20211366. [PMID: 35363256 PMCID: PMC8980842 DOI: 10.1084/jem.20211366] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 12/23/2021] [Accepted: 02/17/2022] [Indexed: 02/02/2023] Open
Abstract
MicroRNAs are critical regulators of gene expression controlling cellular processes including inflammation. We explored their role in the pathogenesis of inflammatory bowel disease (IBD) and identified reduced expression of miR-374a-5p in IBD monocytes that correlated with a module of up-regulated genes related to the inflammatory response. Key proinflammatory module genes, including for example TNFα, IL1A, IL6, and OSM, were inversely correlated with miR-374a-5p and were validated in vitro. In colonic biopsies, miR-374a-5p was again reduced in expression and inversely correlated with the same inflammatory module, and its levels predicted subsequent response to anti-TNF therapy. Increased miR-374a-5p expression was shown to control macrophage-driven inflammation by suppressing proinflammatory mediators and to reduce the capacity of monocytes to migrate and activate T cells. Our findings suggest that miR-374a-5p reduction is a central driver of inflammation in IBD, and its therapeutic supplementation could reduce monocyte-driven inflammation in IBD or other immune-mediated diseases.
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Affiliation(s)
- Carlos Perez-Sanchez
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge, UK
- Rheumatology Service, Reina Sofia University Hospital, Maimonides Biomedical Research Institute of Córdoba, University of Cordoba, Cordoba, Spain
| | - Ariana Barbera Betancourt
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge, UK
| | - Paul A. Lyons
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge, UK
| | - Zinan Zhang
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge, UK
- Molecular Development of the Immune System Section, Laboratory of Immune System Biology and Clinical Genomics Program, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Chenqu Suo
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge, UK
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
- Department of Paediatrics, Cambridge University Hospitals, Cambridge, UK
| | - James C. Lee
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge, UK
| | - Eoin F. McKinney
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge, UK
| | | | | | - Kenneth G.C. Smith
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge, UK
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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16
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Findlay GM. Linking genome variants to disease: scalable approaches to test the functional impact of human mutations. Hum Mol Genet 2021; 30:R187-R197. [PMID: 34338757 PMCID: PMC8490018 DOI: 10.1093/hmg/ddab219] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 07/19/2021] [Accepted: 07/19/2021] [Indexed: 11/13/2022] Open
Abstract
The application of genomics to medicine has accelerated the discovery of mutations underlying disease and has enhanced our knowledge of the molecular underpinnings of diverse pathologies. As the amount of human genetic material queried via sequencing has grown exponentially in recent years, so too has the number of rare variants observed. Despite progress, our ability to distinguish which rare variants have clinical significance remains limited. Over the last decade, however, powerful experimental approaches have emerged to characterize variant effects orders of magnitude faster than before. Fueled by improved DNA synthesis and sequencing and, more recently, by CRISPR/Cas9 genome editing, multiplex functional assays provide a means of generating variant effect data in wide-ranging experimental systems. Here, I review recent applications of multiplex assays that link human variants to disease phenotypes and I describe emerging strategies that will enhance their clinical utility in coming years.
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Affiliation(s)
- Gregory M Findlay
- The Francis Crick Institute, The Genome Function Laboratory, London NW1 1AT, UK
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17
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Functional interrogation of autoimmune disease genetics using CRISPR/Cas9 technologies and massively parallel reporter assays. Semin Immunopathol 2021; 44:137-147. [PMID: 34508276 PMCID: PMC8837574 DOI: 10.1007/s00281-021-00887-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 08/13/2021] [Indexed: 02/07/2023]
Abstract
Genetic studies, including genome-wide association studies, have identified many common variants that are associated with autoimmune diseases. Strikingly, in addition to being frequently observed in healthy individuals, a number of these variants are shared across diseases with diverse clinical presentations. This highlights the potential for improved autoimmune disease understanding which could be achieved by characterising the mechanism by which variants lead to increased risk of disease. Of particular interest is the potential for identifying novel drug targets or of repositioning drugs currently used in other diseases. The majority of autoimmune disease variants do not alter coding regions and it is often difficult to generate a plausible hypothetical mechanism by which variants affect disease-relevant genes and pathways. Given the interest in this area, considerable effort has been invested in developing and applying appropriate methodologies. Two of the most important technologies in this space include both low- and high-throughput genomic perturbation using the CRISPR/Cas9 system and massively parallel reporter assays. In this review, we introduce the field of autoimmune disease functional genomics and use numerous examples to demonstrate the recent and potential future impact of these technologies.
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18
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Torabi Dalivandan S, Plummer J, Gayther SA. Risks and Function of Breast Cancer Susceptibility Alleles. Cancers (Basel) 2021; 13:3953. [PMID: 34439109 PMCID: PMC8393346 DOI: 10.3390/cancers13163953] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 07/30/2021] [Accepted: 07/31/2021] [Indexed: 12/22/2022] Open
Abstract
Family history remains one of the strongest risk factors for breast cancer. It is well established that women with a first-degree relative affected by breast cancer are twice as likely to develop the disease themselves. Twins studies indicate that this is most likely due to shared genetics rather than shared epidemiological/lifestyle risk factors. Linkage and targeted sequencing studies have shown that rare high- and moderate-penetrance germline variants in genes involved in the DNA damage response (DDR) including BRCA1, BRCA2, PALB2, ATM, and TP53 are responsible for a proportion of breast cancer cases. However, breast cancer is a heterogeneous disease, and there is now strong evidence that different risk alleles can predispose to different subtypes of breast cancer. Here, we review the associations between the different genes and subtype-specificity of breast cancer based on the most comprehensive genetic studies published. Genome-wide association studies (GWAS) have also been used to identify an additional hereditary component of breast cancer, and have identified hundreds of common, low-penetrance susceptibility alleles. The combination of these low penetrance risk variants, summed as a polygenic risk score (PRS), can identify individuals across the spectrum of disease risk. However, there remains a substantial bottleneck between the discovery of GWAS-risk variants and their contribution to tumorigenesis mainly because the majority of these variants map to the non-protein coding genome. A range of functional genomic approaches are needed to identify the causal risk variants and target susceptibility genes and establish their underlying role in disease biology. We discuss how the application of these multidisciplinary approaches to understand genetic risk for breast cancer can be used to identify individuals in the population that may benefit from clinical interventions including screening for early detection and prevention, and treatment strategies to reduce breast cancer-related mortalities.
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Affiliation(s)
| | | | - Simon A. Gayther
- Center for Bioinformatics and Functional Genomics, Department of Biomedical Sciences, Cedars Sinai Medical Center, Los Angeles, CA 90048, USA; (S.T.D.); (J.P.)
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19
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Mulvey B, Dougherty JD. Transcriptional-regulatory convergence across functional MDD risk variants identified by massively parallel reporter assays. Transl Psychiatry 2021; 11:403. [PMID: 34294677 PMCID: PMC8298436 DOI: 10.1038/s41398-021-01493-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 06/02/2021] [Accepted: 06/16/2021] [Indexed: 02/07/2023] Open
Abstract
Family and population studies indicate clear heritability of major depressive disorder (MDD), though its underlying biology remains unclear. The majority of single-nucleotide polymorphism (SNP) linkage blocks associated with MDD by genome-wide association studies (GWASes) are believed to alter transcriptional regulators (e.g., enhancers, promoters) based on enrichment of marks correlated with these functions. A key to understanding MDD pathophysiology will be elucidation of which SNPs are functional and how such functional variants biologically converge to elicit the disease. Furthermore, retinoids can elicit MDD in patients and promote depressive-like behaviors in rodent models, acting via a regulatory system of retinoid receptor transcription factors (TFs). We therefore sought to simultaneously identify functional genetic variants and assess retinoid pathway regulation of MDD risk loci. Using Massively Parallel Reporter Assays (MPRAs), we functionally screened over 1000 SNPs prioritized from 39 neuropsychiatric trait/disease GWAS loci, selecting SNPs based on overlap with predicted regulatory features-including expression quantitative trait loci (eQTL) and histone marks-from human brains and cell cultures. We identified >100 SNPs with allelic effects on expression in a retinoid-responsive model system. Functional SNPs were enriched for binding sequences of retinoic acid-receptive transcription factors (TFs), with additional allelic differences unmasked by treatment with all-trans retinoic acid (ATRA). Finally, motifs overrepresented across functional SNPs corresponded to TFs highly specific to serotonergic neurons, suggesting an in vivo site of action. Our application of MPRAs to screen MDD-associated SNPs suggests a shared transcriptional-regulatory program across loci, a component of which is unmasked by retinoids.
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Affiliation(s)
- Bernard Mulvey
- Departments of Genetics and Psychiatry, Washington University in St. Louis, St. Louis, MO, USA
| | - Joseph D Dougherty
- Departments of Genetics and Psychiatry, Washington University in St. Louis, St. Louis, MO, USA.
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20
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Mulvey B, Lagunas T, Dougherty JD. Massively Parallel Reporter Assays: Defining Functional Psychiatric Genetic Variants Across Biological Contexts. Biol Psychiatry 2021; 89:76-89. [PMID: 32843144 PMCID: PMC7938388 DOI: 10.1016/j.biopsych.2020.06.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 06/09/2020] [Accepted: 06/10/2020] [Indexed: 12/18/2022]
Abstract
Neuropsychiatric phenotypes have long been known to be influenced by heritable risk factors, directly confirmed by the past decade of genetic studies that have revealed specific genetic variants enriched in disease cohorts. However, the initial hope that a small set of genes would be responsible for a given disorder proved false. The more complex reality is that a given disorder may be influenced by myriad small-effect noncoding variants and/or by rare but severe coding variants, many de novo. Noncoding genomic sequences-for which molecular functions cannot usually be inferred-harbor a large portion of these variants, creating a substantial barrier to understanding higher-order molecular and biological systems of disease. Fortunately, novel genetic technologies-scalable oligonucleotide synthesis, RNA sequencing, and CRISPR (clustered regularly interspaced short palindromic repeats)-have opened novel avenues to experimentally identify biologically significant variants en masse. Massively parallel reporter assays (MPRAs) are an especially versatile technique resulting from such innovations. MPRAs are powerful molecular genetics tools that can be used to screen thousands of untranscribed or untranslated sequences and their variants for functional effects in a single experiment. This approach, though underutilized in psychiatric genetics, has several useful features for the field. We review methods for assaying putatively functional genetic variants and regions, emphasizing MPRAs and the opportunities they hold for dissection of psychiatric polygenicity. We discuss literature applying functional assays in neurogenetics, highlighting strengths, caveats, and design considerations-especially regarding disease-relevant variables (cell type, neurodevelopment, and sex), and we ultimately propose applications of MPRA to both computational and experimental neurogenetics of polygenic disease risk.
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Affiliation(s)
- Bernard Mulvey
- Division of Biology and Biomedical Sciences, Washington University School of Medicine in St. Louis, St. Louis, Missouri; Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, Missouri; Department of Psychiatry, Washington University School of Medicine in St. Louis, St. Louis, Missouri
| | - Tomás Lagunas
- Division of Biology and Biomedical Sciences, Washington University School of Medicine in St. Louis, St. Louis, Missouri; Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, Missouri; Department of Psychiatry, Washington University School of Medicine in St. Louis, St. Louis, Missouri
| | - Joseph D Dougherty
- Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, Missouri; Department of Psychiatry, Washington University School of Medicine in St. Louis, St. Louis, Missouri.
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21
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González-Serna D, Villanueva-Martin G, Acosta-Herrera M, Márquez A, Martín J. Approaching Shared Pathophysiology in Immune-Mediated Diseases through Functional Genomics. Genes (Basel) 2020; 11:E1482. [PMID: 33317201 PMCID: PMC7762979 DOI: 10.3390/genes11121482] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/01/2020] [Accepted: 12/04/2020] [Indexed: 12/14/2022] Open
Abstract
Immune-mediated diseases (IMDs) are complex pathologies that are strongly influenced by environmental and genetic factors. Associations between genetic loci and susceptibility to these diseases have been widely studied, and hundreds of risk variants have emerged during the last two decades, with researchers observing a shared genetic pattern among them. Nevertheless, the pathological mechanism behind these associations remains a challenge that has just started to be understood thanks to functional genomic approaches. Transcriptomics, regulatory elements, chromatin interactome, as well as the experimental characterization of genomic findings, constitute key elements in the emerging understandings of how genetics affects the etiopathogenesis of IMDs. In this review, we will focus on the latest advances in the field of functional genomics, centering our attention on systemic rheumatic IMDs.
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Affiliation(s)
- David González-Serna
- Institute of Parasitology and Biomedicine López-Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), 18016 Granada, Spain; (D.G.-S.); (G.V.-M.); (M.A.-H.); (A.M.)
| | - Gonzalo Villanueva-Martin
- Institute of Parasitology and Biomedicine López-Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), 18016 Granada, Spain; (D.G.-S.); (G.V.-M.); (M.A.-H.); (A.M.)
| | - Marialbert Acosta-Herrera
- Institute of Parasitology and Biomedicine López-Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), 18016 Granada, Spain; (D.G.-S.); (G.V.-M.); (M.A.-H.); (A.M.)
| | - Ana Márquez
- Institute of Parasitology and Biomedicine López-Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), 18016 Granada, Spain; (D.G.-S.); (G.V.-M.); (M.A.-H.); (A.M.)
- Systemic Autoimmune Disease Unit, Hospital Clínico San Cecilio, Instituto de Investigación Biosanitaria ibs.GRANADA, 18016 Granada, Spain
| | - Javier Martín
- Institute of Parasitology and Biomedicine López-Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), 18016 Granada, Spain; (D.G.-S.); (G.V.-M.); (M.A.-H.); (A.M.)
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Lichou F, Trynka G. Functional studies of GWAS variants are gaining momentum. Nat Commun 2020; 11:6283. [PMID: 33293539 PMCID: PMC7722852 DOI: 10.1038/s41467-020-20188-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 11/16/2020] [Indexed: 11/09/2022] Open
Affiliation(s)
- Florence Lichou
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Gosia Trynka
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK. .,Open Targets, Wellcome Genome Campus, Cambridge, UK.
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23
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Hutchinson A, Asimit J, Wallace C. Fine-mapping genetic associations. Hum Mol Genet 2020; 29:R81-R88. [PMID: 32744321 PMCID: PMC7733401 DOI: 10.1093/hmg/ddaa148] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/04/2020] [Accepted: 07/09/2020] [Indexed: 02/07/2023] Open
Abstract
Whilst thousands of genetic variants have been associated with human traits, identifying the subset of those variants that are causal requires a further 'fine-mapping' step. We review the basic fine-mapping approach, which is computationally fast and requires only summary data, but depends on an assumption of a single causal variant per associated region which is recognized as biologically unrealistic. We discuss different ways that the approach has been built upon to accommodate multiple causal variants in a region and to incorporate additional layers of functional annotation data. We further review methods for simultaneous fine-mapping of multiple datasets, either exploiting different linkage disequilibrium (LD) structures across ancestries or borrowing information between distinct but related traits. Finally, we look to the future and the opportunities that will be offered by increasingly accurate maps of causal variants for a multitude of human traits.
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Affiliation(s)
- Anna Hutchinson
- MRC Biostatistics Unit, Cambridge Biomedical Campus, Cambridge Institute of Public Health, Cambridge CB2 0SR, UK
| | - Jennifer Asimit
- MRC Biostatistics Unit, Cambridge Biomedical Campus, Cambridge Institute of Public Health, Cambridge CB2 0SR, UK
| | - Chris Wallace
- MRC Biostatistics Unit, Cambridge Biomedical Campus, Cambridge Institute of Public Health, Cambridge CB2 0SR, UK
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0AW, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge, CB2 2QQ, UK
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24
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Ding J, Frantzeskos A, Orozco G. Functional genomics in autoimmune diseases. Hum Mol Genet 2020; 29:R59-R65. [PMID: 32420598 PMCID: PMC7530520 DOI: 10.1093/hmg/ddaa097] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 12/11/2022] Open
Abstract
Associations between genetic loci and increased susceptibility to autoimmune disease have been well characterized, however, translating this knowledge into mechanistic insight and patient benefit remains a challenge. While improvements in the precision, completeness and accuracy of our genetic understanding of autoimmune diseases will undoubtedly be helpful, meeting this challenge will require two interlinked problems to be addressed: first which of the highly correlated variants at an individual locus is responsible for increased disease risk, and second what are the downstream effects of this variant. Given that the majority of loci are thought to affect non-coding regulatory elements, the second question is often reframed as what are the target gene(s) and pathways affected by causal variants. Currently, these questions are being addressed using a wide variety of novel techniques and datasets. In many cases, these approaches are complementary and it is likely that the most accurate picture will be generated by consolidating information relating to transcription, regulatory activity, chromatin accessibility, chromatin conformation and readouts from functional experiments, such as genome editing and reporter assays. It is clear that it will be necessary to gather this information from disease relevant cell types and conditions and that by doing so our understanding of disease etiology will be improved. This review is focused on the field of autoimmune disease functional genomics with a particular focus on the most exciting and significant research to be published within the last couple of years.
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Affiliation(s)
- James Ding
- Centre for Genetics and Genomics Versus Arthritis, Division of Musculoskeletal and Dermatological Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9LJ, UK
| | - Antonios Frantzeskos
- Centre for Genetics and Genomics Versus Arthritis, Division of Musculoskeletal and Dermatological Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9LJ, UK
| | - Gisela Orozco
- Centre for Genetics and Genomics Versus Arthritis, Division of Musculoskeletal and Dermatological Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9LJ, UK
- NIHR Manchester Biomedical Research Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester M13 9WL, UK
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25
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Lincoln MR, Axisa PP, Hafler DA. Epigenetic fine-mapping: identification of causal mechanisms for autoimmunity. Curr Opin Immunol 2020; 67:50-56. [PMID: 32977183 DOI: 10.1016/j.coi.2020.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/28/2020] [Accepted: 09/07/2020] [Indexed: 11/25/2022]
Abstract
Genome-wide association studies (GWAS) have identified genetic susceptibility loci for a variety of autoimmune and inflammatory diseases. These studies confirm the fundamental genetic basis of individual autoimmune diseases, and also point to shared etiological mechanisms across the spectrum of autoimmunity. While hundreds of genetic loci have been implicated in autoimmune diseases, the translation of individual susceptibility loci into specific molecular mechanisms for individual diseases remains difficult. This review highlights recent advances in the genetics of autoimmune disease, and the emerging use of epigenetic techniques to identify pathogenic cell types and causal molecular mechanisms of autoimmunity.
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Affiliation(s)
- Matthew R Lincoln
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, USA; Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Pierre-Paul Axisa
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, USA.
| | - David A Hafler
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, USA; Broad Institute of Harvard and MIT, Cambridge, MA, USA
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26
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Nandakumar SK, Liao X, Sankaran VG. In The Blood: Connecting Variant to Function In Human Hematopoiesis. Trends Genet 2020; 36:563-576. [PMID: 32534791 PMCID: PMC7363574 DOI: 10.1016/j.tig.2020.05.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 05/12/2020] [Accepted: 05/13/2020] [Indexed: 02/07/2023]
Abstract
Genome-wide association studies (GWAS) have identified thousands of genetic variants associated with a range of human diseases and traits. However, understanding the mechanisms by which these genetic variants have an impact on associated diseases and traits, often referred to as the variant-to-function (V2F) problem, remains a significant hurdle. Solving the V2F challenge requires us to identify causative genetic variants, relevant cell types/states, target genes, and mechanisms by which variants can cause diseases or alter phenotypic traits. We discuss emerging functional approaches that are being applied to tackle the V2F problem for blood cell traits, illuminating how human genetic variation can impact on key mechanisms in hematopoiesis, as well as highlighting future prospects for this nascent field.
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Affiliation(s)
- Satish K Nandakumar
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of Harvard and Massachusetts Institute of Technology (MIT), Cambridge, MA, USA
| | - Xiaotian Liao
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of Harvard and Massachusetts Institute of Technology (MIT), Cambridge, MA, USA
| | - Vijay G Sankaran
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of Harvard and Massachusetts Institute of Technology (MIT), Cambridge, MA, USA; Harvard Stem Cell Institute, Cambridge, MA, USA.
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27
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Bourges C, Groff AF, Burren OS, Gerhardinger C, Mattioli K, Hutchinson A, Hu T, Anand T, Epping MW, Wallace C, Smith KG, Rinn JL, Lee JC. Resolving mechanisms of immune-mediated disease in primary CD4 T cells. EMBO Mol Med 2020; 12:e12112. [PMID: 32239644 PMCID: PMC7207160 DOI: 10.15252/emmm.202012112] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 03/04/2020] [Accepted: 03/09/2020] [Indexed: 12/11/2022] Open
Abstract
Deriving mechanisms of immune-mediated disease from GWAS data remains a formidable challenge, with attempts to identify causal variants being frequently hampered by strong linkage disequilibrium. To determine whether causal variants could be identified from their functional effects, we adapted a massively parallel reporter assay for use in primary CD4 T cells, the cell type whose regulatory DNA is most enriched for immune-mediated disease SNPs. This enabled the effects of candidate SNPs to be examined in a relevant cellular context and generated testable hypotheses into disease mechanisms. To illustrate the power of this approach, we investigated a locus that has been linked to six immune-mediated diseases but cannot be fine-mapped. By studying the lead expression-modulating SNP, we uncovered an NF-κB-driven regulatory circuit which constrains T-cell activation through the dynamic formation of a super-enhancer that upregulates TNFAIP3 (A20), a key NF-κB inhibitor. In activated T cells, this feedback circuit is disrupted-and super-enhancer formation prevented-by the risk variant at the lead SNP, leading to unrestrained T-cell activation via a molecular mechanism that appears to broadly predispose to human autoimmunity.
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Affiliation(s)
- Christophe Bourges
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
| | - Abigail F Groff
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - Oliver S Burren
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
| | - Chiara Gerhardinger
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - Kaia Mattioli
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - Anna Hutchinson
- MRC Biostatistics Unit, Cambridge Institute of Public Health, Cambridge, UK
| | - Theodore Hu
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
| | - Tanmay Anand
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
| | - Madeline W Epping
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
| | - Chris Wallace
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - Kenneth Gc Smith
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
| | - John L Rinn
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
- Department of Biochemistry, BioFrontiers Institute, University of Colorado, Boulder, CO, USA
| | - James C Lee
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
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