1
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Smith JA, Yuen BTK, Purtha W, Balolong JM, Phipps JD, Crawford F, Bluestone JA, Kappler JW, Anderson MS. Aire mediates tolerance to insulin through thymic trimming of high-affinity T cell clones. Proc Natl Acad Sci U S A 2024; 121:e2320268121. [PMID: 38709934 PMCID: PMC11098115 DOI: 10.1073/pnas.2320268121] [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: 11/27/2023] [Accepted: 03/16/2024] [Indexed: 05/08/2024] Open
Abstract
Insulin is a central autoantigen in the pathogenesis of T1D, and thymic epithelial cell expression of insulin under the control of the Autoimmune Regulator (Aire) is thought to be a key component of maintaining tolerance to insulin. In spite of this general working model, direct detection of this thymic selection on insulin-specific T cells has been somewhat elusive. Here, we used a combination of highly sensitive T cell receptor transgenic models for detecting thymic selection and sorting and sequencing of Insulin-specific CD4+ T cells from Aire-deficient mice as a strategy to further define their selection. This analysis revealed a number of unique t cell receptor (TCR) clones in Aire-deficient hosts with high affinity for insulin/major histocompatibility complex (MHC) ligands. We then modeled the thymic selection of one of these clones in Aire-deficient versus wild-type hosts and found that this model clone could escape thymic negative selection in the absence of thymic Aire. Together, these results suggest that thymic expression of insulin plays a key role in trimming and removing high-affinity insulin-specific T cells from the repertoire to help promote tolerance.
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Affiliation(s)
- Jennifer A. Smith
- Diabetes Center, University of California San Francisco, San Francisco, CA94143
| | - Benjamin T. K. Yuen
- Diabetes Center, University of California San Francisco, San Francisco, CA94143
| | - Whitney Purtha
- Diabetes Center, University of California San Francisco, San Francisco, CA94143
| | - Jared M. Balolong
- Diabetes Center, University of California San Francisco, San Francisco, CA94143
| | - Jonah D. Phipps
- Diabetes Center, University of California San Francisco, San Francisco, CA94143
| | - Frances Crawford
- Department of Immunology and Genomic Medicine, National Jewish Health, Denver, CO80206
| | - Jeffrey A. Bluestone
- Sean N. Parker Autoimmune Research Laboratory, Diabetes Center, University of California, San Francisco, CA94143
| | - John W. Kappler
- Department of Immunology and Genomic Medicine, National Jewish Health, Denver, CO80206
- Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO80045
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO80045
| | - Mark S. Anderson
- Diabetes Center, University of California San Francisco, San Francisco, CA94143
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2
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Berumen J, Orozco L, Gallardo-Rincón H, Juárez-Torres E, Barrera E, Cruz-López M, Benuto RE, Ramos-Martinez E, Marin-Madina M, Alvarado-Silva A, Valladares-Salgado A, Peralta-Romero JJ, García-Ortiz H, Martinez-Juarez LA, Montoya A, Alvarez-Hernández DA, Alegre-Diaz J, Kuri-Morales P, Tapia-Conyer R. Association of tyrosine hydroxylase 01 (TH01) microsatellite and insulin gene (INS) variable number of tandem repeat (VNTR) with type 2 diabetes and fasting insulin secretion in Mexican population. J Endocrinol Invest 2024; 47:571-583. [PMID: 37624484 PMCID: PMC10904573 DOI: 10.1007/s40618-023-02175-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 08/05/2023] [Indexed: 08/26/2023]
Abstract
PURPOSE A variable number of tandem repeats (VNTR) in the insulin gene (INS) control region may be involved in type 2 diabetes (T2D). The TH01 microsatellite is near INS and may regulate it. We investigated whether the TH01 microsatellite and INS VNTR, assessed via the surrogate marker single nucleotide polymorphism rs689, are associated with T2D and serum insulin levels in a Mexican population. METHODS We analyzed a main case-control study (n = 1986) that used univariate and multivariate logistic regression models to calculate the risk conferred by TH01 and rs689 loci for T2D development; rs689 results were replicated in other case-control (n = 1188) and cross-sectional (n = 1914) studies. RESULTS TH01 alleles 6, 8, 9, and 9.3 and allele A of rs689 were independently associated with T2D, with differences between sex and age at diagnosis. TH01 alleles with ≥ 8 repeats conferred an increased risk for T2D in males compared with ≤ 7 repeats (odds ratio, ≥ 1.46; 95% confidence interval, 1.1-1.95). In females, larger alleles conferred a 1.5-fold higher risk for T2D when diagnosed ≥ 46 years but conferred protection when diagnosed ≤ 45 years. Similarly, rs689 allele A was associated with T2D in these groups. In males, larger TH01 alleles and the rs689 A allele were associated with a significant decrease in median fasting plasma insulin concentration with age in T2D cases; the reverse occurred in controls. CONCLUSION Larger TH01 alleles and rs689 A allele may potentiate insulin synthesis in males without T2D, a process disabled in those with T2D.
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Affiliation(s)
- J Berumen
- Facultad de Medicina, Unidad de Investigación en Medicina Experimental, Universidad Nacional Autónoma de México, 06720, Mexico City, México.
| | - L Orozco
- Laboratorio de Inmunogenómica y Enfermedades Metabólicas, Instituto Nacional de Medicina Genómica, Secretaria de Salud, 14610, Mexico City, México
| | - H Gallardo-Rincón
- Departamento de Soluciones Operativas, Fundación Carlos Slim, 11529, Mexico City, Mexico.
- Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Sierra Mojada 950, 44340, Guadalajara, Jalisco, México.
| | - E Juárez-Torres
- Laboratorio Huella Génica, Unidad de Diabetes, 06600, Mexico City, Mexico
| | - E Barrera
- Facultad de Medicina, Unidad de Investigación en Medicina Experimental, Universidad Nacional Autónoma de México, 06720, Mexico City, México
| | - M Cruz-López
- Unidad de Investigación Médica en Bioquímica, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, 06720, Mexico City, México
| | - R E Benuto
- Laboratorio Huella Génica, Unidad de Diabetes, 06600, Mexico City, Mexico
| | - E Ramos-Martinez
- Facultad de Medicina, Unidad de Investigación en Medicina Experimental, Universidad Nacional Autónoma de México, 06720, Mexico City, México
| | - M Marin-Madina
- Laboratorio Huella Génica, Unidad de Diabetes, 06600, Mexico City, Mexico
| | - A Alvarado-Silva
- Laboratorio Huella Génica, Unidad de Diabetes, 06600, Mexico City, Mexico
| | - A Valladares-Salgado
- Unidad de Investigación Médica en Bioquímica, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, 06720, Mexico City, México
| | - J J Peralta-Romero
- Unidad de Investigación Médica en Bioquímica, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, 06720, Mexico City, México
| | - H García-Ortiz
- Laboratorio de Inmunogenómica y Enfermedades Metabólicas, Instituto Nacional de Medicina Genómica, Secretaria de Salud, 14610, Mexico City, México
| | - L A Martinez-Juarez
- Departamento de Soluciones Operativas, Fundación Carlos Slim, 11529, Mexico City, Mexico
- Center for Humanitarian Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - A Montoya
- Departamento de Soluciones Operativas, Fundación Carlos Slim, 11529, Mexico City, Mexico
| | - D A Alvarez-Hernández
- Departamento de Soluciones Operativas, Fundación Carlos Slim, 11529, Mexico City, Mexico
| | - J Alegre-Diaz
- Facultad de Medicina, Unidad de Investigación en Medicina Experimental, Universidad Nacional Autónoma de México, 06720, Mexico City, México
| | - P Kuri-Morales
- Proyecto OriGen, Instituto Tecnologico y de Estudios Superiores de Monterrey, Monterrey, México
| | - R Tapia-Conyer
- Facultad de Medicina, Universidad Nacional Autónoma de México, Coyoacán, 04510, Mexico City, México
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3
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Senaldi L, Hassan N, Cullen S, Balaji U, Trigg N, Gu J, Finkelstein H, Phillips K, Conine C, Smith-Raska M. Khdc3 Regulates Metabolism Across Generations in a DNA-Independent Manner. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.27.582278. [PMID: 38464133 PMCID: PMC10925209 DOI: 10.1101/2024.02.27.582278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Genetic variants can alter the profile of heritable molecules such as small RNAs in sperm and oocytes, and in this manner ancestral genetic variants can have a significant effect on offspring phenotypes even if they are not themselves inherited. Here we show that wild type female mice descended from ancestors with a mutation in the mammalian germ cell gene Khdc3 have hepatic metabolic defects that persist over multiple generations. We find that genetically wild type females descended from Khdc3 mutants have transcriptional dysregulation of critical hepatic metabolic genes, which persist over multiple generations and pass through both female and male lineages. This was associated with dysregulation of hepatically-metabolized molecules in the blood of these wild type mice with mutational ancestry. The oocytes of Khdc3-null females, as well as their wild type descendants, had dysregulation of multiple small RNAs, suggesting that these epigenetic changes in the gametes transmit the phenotype between generations. Our results demonstrate that ancestral mutation in Khdc3 can produce transgenerational inherited phenotypes, potentially indefinitely.
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Affiliation(s)
- Liana Senaldi
- Division of Neonatology, Department of Pediatrics, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
- Drukier Institute for Children's Health, Weill Cornell Medicine, New York, NY, USA
| | - Nora Hassan
- Division of Neonatology, Department of Pediatrics, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
| | - Sean Cullen
- Division of Neonatology, Department of Pediatrics, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
- Drukier Institute for Children's Health, Weill Cornell Medicine, New York, NY, USA
| | - Uthra Balaji
- Drukier Institute for Children's Health, Weill Cornell Medicine, New York, NY, USA
| | - Natalie Trigg
- Departments of Genetics and Paediatrics, University of Pennsylvania Perelman School of Medicine and Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jinghua Gu
- Drukier Institute for Children's Health, Weill Cornell Medicine, New York, NY, USA
| | - Hailey Finkelstein
- Division of Neonatology, Department of Pediatrics, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
| | - Kathryn Phillips
- Division of Neonatology, Department of Pediatrics, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
| | - Colin Conine
- Departments of Genetics and Paediatrics, University of Pennsylvania Perelman School of Medicine and Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Matthew Smith-Raska
- Division of Neonatology, Department of Pediatrics, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
- Drukier Institute for Children's Health, Weill Cornell Medicine, New York, NY, USA
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4
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Allen LA, Taylor PN, Gillespie KM, Oram RA, Dayan CM. Maternal type 1 diabetes and relative protection against offspring transmission. Lancet Diabetes Endocrinol 2023; 11:755-767. [PMID: 37666263 DOI: 10.1016/s2213-8587(23)00190-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 06/12/2023] [Accepted: 06/16/2023] [Indexed: 09/06/2023]
Abstract
Type 1 diabetes is around twice as common in the offspring of men with type 1 diabetes than in the offspring of women with type 1 diabetes, but the reasons for this difference are unclear. This Review summarises the evidence on the rate of transmission of type 1 diabetes to the offspring of affected fathers compared with affected mothers. The findings of nine major studies are presented, describing the magnitude of the effect observed and the relative strengths and weaknesses of these studies. This Review also explores possible underlying mechanisms for this effect, such as genetic mechanisms (eg, the selective loss of fetuses with high-risk genes in mothers with type 1 diabetes, preferential transmission of susceptibility genes from fathers, and parent-of-origin effects influencing gene expression), environmental exposures (eg, exposure to maternal hyperglycaemia, exogenous insulin exposure, and transplacental antibody transfer), and maternal microchimerism. Understanding why type 1 diabetes is more common in the offspring of men versus women with type 1 diabetes will help in the identification of individuals at high risk of the disease and can pave the way in the development of interventions that mimic the protective elements of maternal type 1 diabetes to reduce the risk of disease in individuals at high risk.
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Affiliation(s)
- Lowri A Allen
- Diabetes Research Group, Cardiff University, University Hospital of Wales, Cardiff, UK.
| | - Peter N Taylor
- Diabetes Research Group, Cardiff University, University Hospital of Wales, Cardiff, UK
| | - Kathleen M Gillespie
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Southmead Hospital, Bristol, UK
| | - Richard A Oram
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Royal Devon and Exeter Hospital, Exeter, UK
| | - Colin M Dayan
- Diabetes Research Group, Cardiff University, University Hospital of Wales, Cardiff, UK
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5
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McHale P, Quinlan AR. trfermikit: a tool to discover VNTR-associated deletions. Bioinformatics 2022; 38:1231-1234. [PMID: 34864893 PMCID: PMC8826174 DOI: 10.1093/bioinformatics/btab805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 10/25/2021] [Accepted: 11/27/2021] [Indexed: 02/04/2023] Open
Abstract
SUMMARY We present trfermikit, a software tool designed to detect deletions larger than 50 bp occurring in Variable Number Tandem Repeats using Illumina DNA sequencing reads. In such regions, it achieves a better tradeoff between sensitivity and false discovery than a state-of-the-art structural variation caller, Manta and complements it by recovering a significant number of deletions that Manta missed. trfermikit is based upon the fermikit pipeline, which performs read assembly, maps the assembly to the reference genome and calls variants from the alignment. AVAILABILITY AND IMPLEMENTATION https://github.com/petermchale/trfermikit. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Peter McHale
- Department of Human Genetics and Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT 84112, USA
| | - Aaron R Quinlan
- Department of Human Genetics and Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT 84112, USA
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6
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Cullen SM, Hassan N, Smith-Raska M. Effects of non-inherited ancestral genotypes on offspring phenotypes. Biol Reprod 2021; 105:747-760. [PMID: 34159361 DOI: 10.1093/biolre/ioab120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 11/13/2022] Open
Abstract
It is well established that environmental exposures can modify the profile of heritable factors in an individual's germ cells, ultimately affecting the inheritance of phenotypes in descendants. Similar to exposures, an ancestor's genotype can also affect the inheritance of phenotypes across generations, sometimes in offspring who do not inherit the genetic aberration. This can occur via a variety of prenatal, in utero, or postnatal mechanisms. In this review, we discuss the evidence for this process in mammals, with a focus on examples that are potentially mediated through the germline, while also considering alternate routes of inheritance. Non-inherited ancestral genotypes may influence descendant's disease risk to a much greater extent than currently appreciated, and focused evaluation of this phenomenon may reveal novel mechanisms of inheritance.
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Affiliation(s)
- Sean M Cullen
- Division of Newborn Medicine, Department of Pediatrics, Weill Cornell Medicine, 413 East 69th Street, Room 1252D, New York, NY 10021
| | - Nora Hassan
- Division of Newborn Medicine, Department of Pediatrics, Weill Cornell Medicine, 413 East 69th Street, Room 1252D, New York, NY 10021
| | - Matthew Smith-Raska
- Division of Newborn Medicine, Department of Pediatrics, Weill Cornell Medicine, 413 East 69th Street, Room 1252D, New York, NY 10021
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7
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Polygenic inheritance, GWAS, polygenic risk scores, and the search for functional variants. Proc Natl Acad Sci U S A 2020; 117:18924-18933. [PMID: 32753378 DOI: 10.1073/pnas.2005634117] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The reconciliation between Mendelian inheritance of discrete traits and the genetically based correlation between relatives for quantitative traits was Fisher's infinitesimal model of a large number of genetic variants, each with very small effects, whose causal effects could not be individually identified. The development of genome-wide genetic association studies (GWAS) raised the hope that it would be possible to identify single polymorphic variants with identifiable functional effects on complex traits. It soon became clear that, with larger and larger GWAS on more and more complex traits, most of the significant associations had such small effects, that identifying their individual functional effects was essentially hopeless. Polygenic risk scores that provide an overall estimate of the genetic propensity to a trait at the individual level have been developed using GWAS data. These provide useful identification of groups of individuals with substantially increased risks, which can lead to recommendations of medical treatments or behavioral modifications to reduce risks. However, each such claim will require extensive investigation to justify its practical application. The challenge now is to use limited genetic association studies to find individually identifiable variants of significant functional effect that can help to understand the molecular basis of complex diseases and traits, and so lead to improved disease prevention and treatment. This can best be achieved by 1) the study of rare variants, often chosen by careful candidate assessment, and 2) the careful choice of phenotypes, often extremes of a quantitative variable, or traits with relatively high heritability.
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8
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Matsumoto M, Tsuneyama K, Morimoto J, Hosomichi K, Matsumoto M, Nishijima H. Tissue-specific autoimmunity controlled by Aire in thymic and peripheral tolerance mechanisms. Int Immunol 2020; 32:117-131. [PMID: 31586207 PMCID: PMC7005526 DOI: 10.1093/intimm/dxz066] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Accepted: 10/02/2019] [Indexed: 01/14/2023] Open
Abstract
Tissue-specific autoimmune diseases are assumed to arise through malfunction of two checkpoints for immune tolerance: defective elimination of autoreactive T cells in the thymus and activation of these T cells by corresponding autoantigens in the periphery. However, evidence for this model and the outcome of such alterations in each or both of the tolerance mechanisms have not been sufficiently investigated. We studied these issues by expressing human AIRE (huAIRE) as a modifier of tolerance function in NOD mice wherein the defects of thymic and peripheral tolerance together cause type I diabetes (T1D). Additive huAIRE expression in the thymic stroma had no major impact on the production of diabetogenic T cells in the thymus. In contrast, huAIRE expression in peripheral antigen-presenting cells (APCs) rendered the mice resistant to T1D, while maintaining other tissue-specific autoimmune responses and antibody production against an exogenous protein antigen, because of the loss of Xcr1+ dendritic cells, an essential component for activating diabetogenic T cells in the periphery. These results contrast with our recent demonstration that huAIRE expression in both the thymic stroma and peripheral APCs resulted in the paradoxical development of muscle-specific autoimmunity. Our results reveal that tissue-specific autoimmunity is differentially controlled by a combination of thymic function and peripheral tolerance, which can be manipulated by expression of huAIRE/Aire in each or both of the tolerance mechanisms.
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Affiliation(s)
- Minoru Matsumoto
- Division of Molecular Immunology, Institute for Enzyme Research, Tokushima University, Tokushima, Japan
- Department of Pathology and Laboratory Medicine, Tokushima University Graduate School, Tokushima, Japan
| | - Koichi Tsuneyama
- Department of Pathology and Laboratory Medicine, Tokushima University Graduate School, Tokushima, Japan
| | - Junko Morimoto
- Division of Molecular Immunology, Institute for Enzyme Research, Tokushima University, Tokushima, Japan
| | - Kazuyoshi Hosomichi
- Department of Bioinformatics and Genomics, Graduate School of Medical Sciences, Kanazawa University, Ishikawa, Japan
| | - Mitsuru Matsumoto
- Division of Molecular Immunology, Institute for Enzyme Research, Tokushima University, Tokushima, Japan
| | - Hitoshi Nishijima
- Division of Molecular Immunology, Institute for Enzyme Research, Tokushima University, Tokushima, Japan
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9
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Martinov T, Fife BT. Type 1 diabetes pathogenesis and the role of inhibitory receptors in islet tolerance. Ann N Y Acad Sci 2020; 1461:73-103. [PMID: 31025378 PMCID: PMC6994200 DOI: 10.1111/nyas.14106] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 03/25/2019] [Accepted: 04/03/2019] [Indexed: 12/15/2022]
Abstract
Type 1 diabetes (T1D) affects over a million Americans, and disease incidence is on the rise. Despite decades of research, there is still no cure for this disease. Exciting beta cell replacement strategies are being developed, but in order for such approaches to work, targeted immunotherapies must be designed. To selectively halt the autoimmune response, researchers must first understand how this response is regulated and which tolerance checkpoints fail during T1D development. Herein, we discuss the current understanding of T1D pathogenesis in humans, genetic and environmental risk factors, presumed roles of CD4+ and CD8+ T cells as well as B cells, and implicated autoantigens. We also highlight studies in non-obese diabetic mice that have demonstrated the requirement for CD4+ and CD8+ T cells and B cells in driving T1D pathology. We present an overview of central and peripheral tolerance mechanisms and comment on existing controversies in the field regarding central tolerance. Finally, we discuss T cell- and B cell-intrinsic tolerance mechanisms, with an emphasis on the roles of inhibitory receptors in maintaining islet tolerance in humans and in diabetes-prone mice, and strategies employed to date to harness inhibitory receptor signaling to prevent or reverse T1D.
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Affiliation(s)
- Tijana Martinov
- Department of Medicine, Center for Immunology, University of Minnesota Medical School, Minneapolis, Minnesota
| | - Brian T Fife
- Department of Medicine, Center for Immunology, University of Minnesota Medical School, Minneapolis, Minnesota
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10
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Kamel AM, Mira MF, Ebid GTA, Kassem SH, Radwan ER, Mamdouh M, Amin M, Badawy N, Bazaraa H, Ibrahim A, Salah N. Association of insulin gene VNTR INS -23/Hph1 A>T (rs689) polymorphism with type 1 diabetes mellitus in Egyptian children. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2019. [DOI: 10.1186/s43042-019-0017-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Type1 diabetes mellitus (T1DM) has a multi-factorial pathogenesis; the interplay between genetic susceptibility and environmental factors is thought to provide the fundamental element for the disease. Apart from HLA, more than 50 genetic variants are associated with T1DM. INS -23/Hph1 A>T (rs689) is one of the effective loci with inconsistent reports in the literature. Accordingly, this study was designed to define the frequencies of INS -23/Hph1 A>T polymorphism and its association with T1DM in Egyptian diabetic children and their non-diabetic family members as compared to healthy controls.
Methods
Using polymerase chain reaction-restriction fragment length polymorphism methodology, analysis of insulin gene VNTR polymorphism was performed for 496 samples (91 patients, 179 parents, 130 siblings, and 96 controls); parents and siblings were apparently healthy.
Results
INS genotypes and allele frequencies were comparable between patients, non-diabetic siblings, and parents (p = 0.97 and 0.77, respectively). However, the TT/AT genotype and T allele were over-presented in the three family groups compared to controls (p = 0.0015 and 0.0029, respectively).
Comparing patients to controls, the T allele is considered a risk factor for the development of TIDM (OR 2.56, 95% CI 1.42–4.62, p = 0.0017).
INS -23/Hph1 A>T polymorphism showed concordance between patients and their mothers (Kappa = 0.446, p = 0.000) but not with their fathers (Kappa = 0.031, p = 0.765).
Conclusions
INS -23/Hph1 A>T gene polymorphism was shown to be a risk factor for the development of TIDM. This is in agreement with some and in disagreement with other reports. Studies of risk susceptibility factors have to be carried out locally in each community; results cannot be extrapolated from one ethnic group to another.
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11
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Yang B, Etheridge T, McCormick J, Schultz A, Khemees TA, Damaschke N, Leverson G, Woo K, Sonn GA, Klein EA, Fumo M, Huang W, Jarrard DF. Validation of an epigenetic field of susceptibility to detect significant prostate cancer from non-tumor biopsies. Clin Epigenetics 2019; 11:168. [PMID: 31779677 PMCID: PMC6883627 DOI: 10.1186/s13148-019-0771-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 10/22/2019] [Indexed: 12/18/2022] Open
Abstract
Background An epigenetic field of cancer susceptibility exists for prostate cancer (PC) that gives rise to multifocal disease in the peripheral prostate. In previous work, genome-wide DNA methylation profiling identified altered regions in the normal prostate tissue of men with PC. In the current multicenter study, we examined the predictive strength of a panel of loci to detect cancer presence and grade in patients with negative biopsy tissue. Results Four centers contributed benign prostate biopsy tissues blocks from 129 subjects that were either tumor associated (TA, Grade Group [GG] ≥ 2, n = 77) or non-tumor associated (NTA, n = 52). Biopsies were analyzed using pyrosequencing for DNA methylation encompassing CpG loci near CAV1, EVX1, FGF1, NCR2, PLA2G16, and SPAG4 and methylation differences were detected within all gene regions (p < 0.05). A multiplex regression model for biomarker performance incorporating a gene combination discriminated TA from NTA tissues (area under the curve [AUC] 0.747, p = 0.004). A multiplex model incorporating all the above genes and clinical information (PSA, age) identified patients with GG ≥ 2 PC (AUC 0.815, p < 0.0001). In patients with cancer, increased variation in gene methylation levels occurs between biopsies across the prostate. Conclusions A widespread epigenetic field defect is utilized to detect GG ≥ 2 PC in patients with histologically negative biopsies. These alterations in non-tumor cells display increased heterogeneity of methylation extent and are spatially distant from tumor foci. These findings have the potential to decrease the need for repeated prostate biopsy.
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Affiliation(s)
- Bing Yang
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Tyler Etheridge
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Johnathon McCormick
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Adam Schultz
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Tariq A Khemees
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA.,Department of Urology, University of Wisconsin, Madison, WI, 53705, USA
| | - Nathan Damaschke
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Glen Leverson
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Kaitlin Woo
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | | | - Eric A Klein
- Cleveland Clinic, Glickman Urological and Kidney Institute, Cleveland, OH, USA
| | - Mike Fumo
- Rockford Urologic, Rockford, IL, USA
| | - Wei Huang
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA.,Carbone Comprehensive Cancer Center, University of Wisconsin, Madison, WI, 53705, USA
| | - David F Jarrard
- University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA. .,Department of Urology, University of Wisconsin, Madison, WI, 53705, USA. .,Carbone Comprehensive Cancer Center, University of Wisconsin, Madison, WI, 53705, USA. .,Molecular and Environmental Toxicology Program, University of Wisconsin, Madison, WI, 53705, USA.
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12
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Frommer L, Kahaly GJ. Autoimmune Polyendocrinopathy. J Clin Endocrinol Metab 2019; 104:4769-4782. [PMID: 31127843 DOI: 10.1210/jc.2019-00602] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 04/22/2019] [Indexed: 02/06/2023]
Abstract
CONTEXT This mini-review offers an update on the rare autoimmune polyendocrinopathy (AP) syndrome with a synopsis of recent developments. DESIGN AND RESULTS Systematic search for studies related to pathogenesis, immunogenetics, screening, diagnosis, clinical spectrum, and epidemiology of AP. AP (orphan code ORPHA 282196) is defined as the autoimmune-induced failure of at least two glands. AP is divided into the rare juvenile type I and the adult types II to IV. The prevalence is 1:100,000 and 1:20,000 for types I and types II to IV, respectively. Whereas type I (ORPHA 3453) is a monogenetic syndrome with an autosomal recessive transmission related to mutations in the autoimmune regulator (AIRE) gene, types II to IV are genetically complex multifactorial syndromes that are strongly associated with certain alleles of HLA genes within the major histocompatibility complex located on chromosome 6, as well as the cytotoxic T lymphocyte antigen 4 and the protein tyrosine phosphatase nonreceptor type 22 genes. Addison disease is the major endocrine component of type II (ORPHA 3143), whereas the coexistence of type 1 diabetes and autoimmune thyroid disease is characteristic for type III (ORPHA 227982). Genetic screening for the AIRE gene is useful in patients with suspected type I, whereas serological screening (i.e., diabetes/adrenal antibodies) is required in patients with monoglandular autoimmunity and suspected AP. If positive, functional endocrine testing of the antibody-positive patients as well as serological screening of their first-degree relatives is recommended. CONCLUSION Timely diagnosis, genetic counseling, and optimal long-term management of AP is best offered in specialized centers.
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Affiliation(s)
- Lara Frommer
- Orphan Disease Center for Autoimmune Polyendocrinopathy, Department of Medicine I, Johannes Gutenberg University Medical Center, Mainz, Germany
| | - George J Kahaly
- Orphan Disease Center for Autoimmune Polyendocrinopathy, Department of Medicine I, Johannes Gutenberg University Medical Center, Mainz, Germany
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13
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Chen J, Sun M, Adeyemo A, Pirie F, Carstensen T, Pomilla C, Doumatey AP, Chen G, Young EH, Sandhu M, Morris AP, Barroso I, McCarthy MI, Mahajan A, Wheeler E, Rotimi CN, Motala AA. Genome-wide association study of type 2 diabetes in Africa. Diabetologia 2019; 62:1204-1211. [PMID: 31049640 PMCID: PMC6560001 DOI: 10.1007/s00125-019-4880-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 03/22/2019] [Indexed: 02/02/2023]
Abstract
AIMS/HYPOTHESIS Genome-wide association studies (GWAS) for type 2 diabetes have uncovered >400 risk loci, primarily in populations of European and Asian ancestry. Here, we aimed to discover additional type 2 diabetes risk loci (including African-specific variants) and fine-map association signals by performing genetic analysis in African populations. METHODS We conducted two type 2 diabetes genome-wide association studies in 4347 Africans from South Africa, Nigeria, Ghana and Kenya and meta-analysed both studies together. Likely causal variants were identified using fine-mapping approaches. RESULTS The most significantly associated variants mapped to the widely replicated type 2 diabetes risk locus near TCF7L2 (p = 5.3 × 10-13). Fine-mapping of the TCF7L2 locus suggested one type 2 diabetes association signal shared between Europeans and Africans (indexed by rs7903146) and a distinct African-specific signal (indexed by rs17746147). We also detected one novel signal, rs73284431, near AGMO (p = 5.2 × 10-9, minor allele frequency [MAF] = 0.095; monomorphic in most non-African populations), distinct from previously reported signals in the region. In analyses focused on 100 published type 2 diabetes risk loci, we identified 21 with shared causal variants in African and non-African populations. CONCLUSIONS/INTERPRETATION These results demonstrate the value of performing GWAS in Africans, provide a resource to larger consortia for further discovery and fine-mapping and indicate that additional large-scale efforts in Africa are warranted to gain further insight in to the genetic architecture of type 2 diabetes.
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Affiliation(s)
- Ji Chen
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - Meng Sun
- Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Adebowale Adeyemo
- Center for Research on Genomics and Global Heath, National Human Genome Research Institute, National Institute of Health, Bethesda, MD, USA
| | - Fraser Pirie
- Department of Diabetes and Endocrinology, University of KwaZulu-Natal, Durban, 4013, South Africa
| | - Tommy Carstensen
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Cristina Pomilla
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Ayo P Doumatey
- Center for Research on Genomics and Global Heath, National Human Genome Research Institute, National Institute of Health, Bethesda, MD, USA
| | - Guanjie Chen
- Center for Research on Genomics and Global Heath, National Human Genome Research Institute, National Institute of Health, Bethesda, MD, USA
| | - Elizabeth H Young
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Manjinder Sandhu
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Andrew P Morris
- Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
- Department of Biostatistics, University of Liverpool, Liverpool, UK
| | - Inês Barroso
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Institute of Metabolic Science, Cambridge Biomedical Campus, Cambridge, CB2 0QQ, UK
| | - Mark I McCarthy
- Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK
- Oxford NIHR Biomedical Research Centre, Oxford, UK
| | - Anubha Mahajan
- Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK.
| | - Eleanor Wheeler
- Wellcome Sanger Institute, Hinxton, Cambridge, UK.
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Institute of Metabolic Science, Cambridge Biomedical Campus, Cambridge, CB2 0QQ, UK.
| | - Charles N Rotimi
- Center for Research on Genomics and Global Heath, National Human Genome Research Institute, National Institute of Health, Bethesda, MD, USA.
| | - Ayesha A Motala
- Department of Diabetes and Endocrinology, University of KwaZulu-Natal, Durban, 4013, South Africa.
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14
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Buzzetti R, Zampetti S, Maddaloni E. Adult-onset autoimmune diabetes: current knowledge and implications for management. Nat Rev Endocrinol 2017; 13:674-686. [PMID: 28885622 DOI: 10.1038/nrendo.2017.99] [Citation(s) in RCA: 155] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Adult-onset autoimmune diabetes is a heterogeneous disease that is characterized by a reduced genetic load, a less intensive autoimmune process and a mild metabolic decompensation at onset compared with young-onset type 1 diabetes mellitus (T1DM). The majority of patients with adult-onset autoimmune diabetes do not require insulin treatment for at least 6 months after diagnosis. Such patients are defined as having latent autoimmune diabetes in adults (LADA), which is distinct from classic adult-onset T1DM. The extensive heterogeneity of adult-onset autoimmune diabetes is apparent beyond the distinction between classic adult-onset T1DM and LADA. LADA is characterized by genetic, phenotypic and humoral heterogeneity, encompassing different degrees of insulin resistance and autoimmunity; this heterogeneity is probably a result of different pathological mechanisms, which have implications for treatment. The existence of heterogeneous phenotypes in LADA makes it difficult to establish an a priori treatment algorithm, and therefore, a personalized medicine approach is required. In this Review, we discuss the current understanding and gaps in knowledge regarding the pathophysiology and clinical features of adult-onset autoimmune diabetes and highlight the similarities and differences with classic T1DM and type 2 diabetes mellitus.
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Affiliation(s)
- Raffaella Buzzetti
- Department of Experimental Medicine, Sapienza University, Viale Regina Elena 324, 00161, Rome, Italy
| | - Simona Zampetti
- Department of Experimental Medicine, Sapienza University, Viale Regina Elena 324, 00161, Rome, Italy
| | - Ernesto Maddaloni
- Department of Medicine, Unit of Endocrinology and Diabetes, University Campus Bio-Medico, Via Álvaro del Portillo 21, 00128, Rome, Italy
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15
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Shang K, Talmage DA, Karl T. Parent-of-origin effects on schizophrenia-relevant behaviours of type III neuregulin 1 mutant mice. Behav Brain Res 2017; 332:250-258. [DOI: 10.1016/j.bbr.2017.05.057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 04/29/2017] [Accepted: 05/24/2017] [Indexed: 12/18/2022]
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16
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Gomes KFB, Santos AS, Semzezem C, Correia MR, Brito LA, Ruiz MO, Fukui RT, Matioli SR, Passos-Bueno MR, Silva MERD. The influence of population stratification on genetic markers associated with type 1 diabetes. Sci Rep 2017; 7:43513. [PMID: 28262800 PMCID: PMC5338024 DOI: 10.1038/srep43513] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 01/26/2017] [Indexed: 12/17/2022] Open
Abstract
Ethnic admixtures may interfere with the definition of type 1 diabetes (T1D) risk determinants. The role of HLA, PTPN22, INS-VNTR, and CTLA4 in T1D predisposition was analyzed in Brazilian T1D patients (n = 915), with 81.7% self-reporting as white and 789 controls (65.6% white). The results were corrected for population stratification by genotyping 93 ancestry informative markers (AIMs) (BeadXpress platform). Ancestry composition and structural association were characterized using Structure 2.3 and STRAT. Ethnic diversity resulted in T1D determinants that were partially discordant from those reported in Caucasians and Africans. The greatest contributor to T1D was the HLA-DR3/DR4 genotype (OR = 16.5) in 23.9% of the patients, followed by -DR3/DR3 (OR = 8.9) in 8.7%, -DR4/DR4 (OR = 4.7) in 6.0% and -DR3/DR9 (OR = 4.9) in 2.6%. Correction by ancestry also confirmed that the DRB1*09-DQB1*0202 haplotype conferred susceptibility, whereas the DRB1*07-DQB1*0202 and DRB1*11-DQB1*0602 haplotypes were protective, which is similar to reports in African-American patients. By contrast, the DRB1*07-DQB1*0201 haplotype was protective in our population and in Europeans, despite conferring susceptibility to Africans. The DRB1*10-DQB1*0501 haplotype was only protective in the Brazilian population. Predisposition to T1D conferred by PTPN22 and INS-VNTR and protection against T1D conferred by the DRB1*16 allele were confirmed. Correcting for population structure is important to clarify the particular genetic variants that confer susceptibility/protection for T1D in populations with ethnic admixtures.
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Affiliation(s)
- Karla Fabiana Brasil Gomes
- Laboratório de Carboidratos e Radioimunoensaio (LIM-18) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av. Dr. Arnaldo, 455, sala 3324, 01246-903, São Paulo, São Paulo, Brazil
| | - Aritânia Sousa Santos
- Laboratório de Carboidratos e Radioimunoensaio (LIM-18) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av. Dr. Arnaldo, 455, sala 3324, 01246-903, São Paulo, São Paulo, Brazil
| | - Cintia Semzezem
- Laboratório de Carboidratos e Radioimunoensaio (LIM-18) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av. Dr. Arnaldo, 455, sala 3324, 01246-903, São Paulo, São Paulo, Brazil
| | - Márcia Regina Correia
- Laboratório de Carboidratos e Radioimunoensaio (LIM-18) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av. Dr. Arnaldo, 455, sala 3324, 01246-903, São Paulo, São Paulo, Brazil
| | - Luciano Abreu Brito
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências da Universidade de São Paulo. Rua do Matão, 277, 05422-970, São Paulo, São Paulo, Brazil
| | - Marcelo Ortega Ruiz
- Laboratório de Imunologia, Rua Claudio Manoel da Costa, 270, Marília, São Paulo, Brazil
| | - Rosa Tsuneshiro Fukui
- Laboratório de Carboidratos e Radioimunoensaio (LIM-18) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av. Dr. Arnaldo, 455, sala 3324, 01246-903, São Paulo, São Paulo, Brazil
| | - Sergio Russo Matioli
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências da Universidade de São Paulo. Rua do Matão, 277, 05422-970, São Paulo, São Paulo, Brazil
| | - Maria Rita Passos-Bueno
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências da Universidade de São Paulo. Rua do Matão, 277, 05422-970, São Paulo, São Paulo, Brazil
| | - Maria Elizabeth Rossi da Silva
- Laboratório de Carboidratos e Radioimunoensaio (LIM-18) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av. Dr. Arnaldo, 455, sala 3324, 01246-903, São Paulo, São Paulo, Brazil
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17
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Michels AW, Landry LG, McDaniel KA, Yu L, Campbell-Thompson M, Kwok WW, Jones KL, Gottlieb PA, Kappler JW, Tang Q, Roep BO, Atkinson MA, Mathews CE, Nakayama M. Islet-Derived CD4 T Cells Targeting Proinsulin in Human Autoimmune Diabetes. Diabetes 2017; 66:722-734. [PMID: 27920090 PMCID: PMC5319719 DOI: 10.2337/db16-1025] [Citation(s) in RCA: 147] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 12/01/2016] [Indexed: 12/16/2022]
Abstract
Type 1 diabetes results from chronic autoimmune destruction of insulin-producing β-cells within pancreatic islets. Although insulin is a critical self-antigen in animal models of autoimmune diabetes, due to extremely limited access to pancreas samples, little is known about human antigenic targets for islet-infiltrating T cells. Here we show that proinsulin peptides are targeted by islet-infiltrating T cells from patients with type 1 diabetes. We identified hundreds of T cells from inflamed pancreatic islets of three young organ donors with type 1 diabetes with a short disease duration with high-risk HLA genes using a direct T-cell receptor (TCR) sequencing approach without long-term cell culture. Among 85 selected CD4 TCRs tested for reactivity to preproinsulin peptides presented by diabetes-susceptible HLA-DQ and HLA-DR molecules, one T cell recognized C-peptide amino acids 19-35, and two clones from separate donors responded to insulin B-chain amino acids 9-23 (B:9-23), which are known to be a critical self-antigen-driving disease progress in animal models of autoimmune diabetes. These B:9-23-specific T cells from islets responded to whole proinsulin and islets, whereas previously identified B:9-23 responsive clones from peripheral blood did not, highlighting the importance of proinsulin-specific T cells in the islet microenvironment.
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Affiliation(s)
- Aaron W Michels
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Laurie G Landry
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Kristen A McDaniel
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Liping Yu
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Martha Campbell-Thompson
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL
| | - William W Kwok
- Benaroya Research Institute at Virginia Mason, Seattle, WA
- Department of Medicine, University of Washington, Seattle, WA
| | - Kenneth L Jones
- Department of Pediatrics, Section of Hematology, Oncology, and Bone Marrow Transplant, University of Colorado School of Medicine, Aurora, CO
| | - Peter A Gottlieb
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - John W Kappler
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
- Howard Hughes Medical Institute, Denver, CO
- Department of Biomedical Research, National Jewish Health, Denver, CO
- Program in Structural Biology and Biochemistry, University of Colorado School of Medicine, Aurora, CO
| | - Qizhi Tang
- Department of Surgery, University of California, San Francisco, San Francisco, CA
- Diabetes Center, University of California, San Francisco, San Francisco, CA
| | - Bart O Roep
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, the Netherlands
- Department of Diabetes Immunology, Diabetes & Metabolism Research Institute, Beckman Research Institute of City of Hope, Duarte, CA
| | - Mark A Atkinson
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL
| | - Maki Nakayama
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
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18
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Thayer TC, Pearson JA, De Leenheer E, Hanna SJ, Boldison J, Davies J, Tsui A, Ahmed S, Easton P, Siew LK, Wen L, Wong FS. Peripheral Proinsulin Expression Controls Low-Avidity Proinsulin-Reactive CD8 T Cells in Type 1 Diabetes. Diabetes 2016; 65:3429-3439. [PMID: 27495224 DOI: 10.2337/db15-1649] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 07/26/2016] [Indexed: 11/13/2022]
Abstract
Low-avidity autoreactive CD8 T cells (CTLs) escape from thymic negative selection, and peripheral tolerance mechanisms are essential for their regulation. We report the role of proinsulin (PI) expression on the development and activation of insulin-specific CTLs in the NOD mouse model of type 1 diabetes. We studied insulin B-chain-specific CTL from different T-cell receptor transgenic mice (G9Cα-/-) expressing normal PI1 and PI2 or altered PI expression levels. In the absence of PI2 (Ins2-/-), CTL in pancreatic lymph nodes (PLNs) were more activated, and male G9Cα-/- mice developed T1D. Furthermore, when the insulin-specific CTLs developed in transgenic mice lacking their specific PI epitope, the CTLs demonstrated increased cytotoxicity and proliferation in vitro and in vivo in the PLNs after adoptive transfer into NOD recipients. Dendritic cell-stimulated proliferation of insulin-specific T cells was reduced in the presence of lymph node stromal cells (LNSCs) from NOD mice but not from mice lacking the PI epitope. Our study shows that LNSCs regulate CTL activation and suggests that exposure to PI in the periphery is very important in maintenance of tolerance of autoreactive T cells. This is relevant for human type 1 diabetes and has implications for the use of antigen-specific therapy in tolerance induction.
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Affiliation(s)
- Terri C Thayer
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - James A Pearson
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - Evy De Leenheer
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - Stephanie J Hanna
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - Joanne Boldison
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - Joanne Davies
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - Adrian Tsui
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - Sartaj Ahmed
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - Peter Easton
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - Lai Khai Siew
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K
| | - Li Wen
- Section of Endocrinology, Yale School of Medicine, New Haven, CT
| | - F Susan Wong
- Diabetes Research Group, Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff University, Cardiff, U.K.
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19
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Fox LA, Mubasher M, Wolfsdorf JI, Buckingham BA, Peters AL, Tamborlane WV, Schatz DA, Maahs DM, Miller KM, Beck RW. Characteristics of youth with type 1 diabetes (T1D) with and without a parent with T1D in the T1D exchange clinic registry. J Diabetes 2016; 8:834-838. [PMID: 26663683 DOI: 10.1111/1753-0407.12363] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 12/02/2015] [Accepted: 12/04/2015] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The aim of the present study was to compare characteristics and diabetes management in children and adolescents with and without at least one parent with type 1 diabetes (T1D). METHODS In all, 12 890 participants aged <18 years at enrollment in the T1D Exchange Registry were included in the present study. Statistical comparisons between those with and without parental T1D were conducted using a univariate generalized linear mixed model. RESULTS Of the study participants, 1056 (8.2%) registrants had at least one parent with T1D. Those with parental T1D were slightly, albeit significantly, younger (6.3 vs 6.9 years; P < 0.001) and less likely to have diabetic ketoacidosis (DKA) at diagnosis (24% vs 41%; P < 0.001) than those without parental T1D. There were no differences between groups in HbA1c, use of continuous glucose monitoring or insulin pump therapy, or the development of severe hypoglycemia or DKA. In addition, there were no differences found when comparing characteristics or diabetes management in those with a mother versus those with a father with T1D. CONCLUSIONS Children and adolescents with parental T1D tend to be diagnosed earlier. Diabetes management, glycemic control, and acute complications are similar in those with and without parental T1D.
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Affiliation(s)
- Larry A Fox
- Nemours Children's Specialty Care, Jacksonville
| | | | | | | | - Anne L Peters
- Keck School of Medicine, University of Southern California, Los Angeles, California
| | | | | | - David M Maahs
- Barbara Davis Center for Childhood Diabetes, Aurora, Colorado, USA
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21
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Yang B, Damaschke N, Yao T, McCormick J, Wagner J, Jarrard D. Pyrosequencing for accurate imprinted allele expression analysis. J Cell Biochem 2016; 116:1165-70. [PMID: 25581900 DOI: 10.1002/jcb.25081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 01/05/2015] [Indexed: 01/14/2023]
Abstract
Genomic imprinting is an epigenetic mechanism that restricts gene expression to one inherited allele. Improper maintenance of imprinting has been implicated in a number of human diseases and developmental syndromes. Assays are needed that can quantify the contribution of each paternal allele to a gene expression profile. We have developed a rapid, sensitive quantitative assay for the measurement of individual allelic ratios termed Pyrosequencing for Imprinted Expression (PIE). Advantages of PIE over other approaches include shorter experimental time, decreased labor, avoiding the need for restriction endonuclease enzymes at polymorphic sites, and prevent heteroduplex formation which is problematic in quantitative PCR-based methods. We demonstrate the improved sensitivity of PIE including the ability to detect differences in allelic expression down to 1%. The assay is capable of measuring genomic heterozygosity as well as imprinting in a single run. PIE is applied to determine the status of Insulin-like Growth Factor-2 (IGF2) imprinting in human and mouse tissues.
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Affiliation(s)
- Bing Yang
- Department of Urology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Nathan Damaschke
- Department of Urology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Tianyu Yao
- Department of Urology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Johnathon McCormick
- Department of Urology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Jennifer Wagner
- Department of Urology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - David Jarrard
- Department of Urology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin.,University of Wisconsin Carbone Comprehensive Cancer Center, Madison, Wisconsin.,Environmental and Molecular Toxicology, University of Wisconsin, Madison, Wisconsin
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22
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Gabriel JM, Hollick JB. Paramutation in maize and related behaviors in metazoans. Semin Cell Dev Biol 2015; 44:11-21. [PMID: 26318741 DOI: 10.1016/j.semcdb.2015.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Accepted: 08/18/2015] [Indexed: 12/31/2022]
Abstract
Paramutation refers to both the process and results of trans-homolog interactions causing heritable changes in both gene regulation and silencing abilities. Originally described in plants, paramutation-like behaviors have now been reported in model metazoans. Here we detail our current understanding of the paramutation mechanism as defined in Zea mays and compare this paradigm to these metazoan examples. Experimental results implicate functional roles of small RNAs in all these model organisms that highlight a diversity of mechanisms by which these molecules specify meiotically heritable regulatory information in the eukarya.
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Affiliation(s)
- Janelle M Gabriel
- Department of Molecular Genetics, Center for RNA Biology, The Ohio State University, Columbus, OH, USA
| | - Jay B Hollick
- Department of Molecular Genetics, Center for RNA Biology, The Ohio State University, Columbus, OH, USA.
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23
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Pilu R. Paramutation phenomena in plants. Semin Cell Dev Biol 2015; 44:2-10. [DOI: 10.1016/j.semcdb.2015.08.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Accepted: 08/26/2015] [Indexed: 02/05/2023]
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24
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Slyvka Y, Zhang Y, Nowak FV. Epigenetic effects of paternal diet on offspring: emphasis on obesity. Endocrine 2015; 48:36-46. [PMID: 24997644 DOI: 10.1007/s12020-014-0328-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 06/05/2014] [Indexed: 12/21/2022]
Abstract
Overnutrition, obesity, and the rise in associated comorbidities are widely recognized as preventable challenges to global health. Behavioral, metabolic, and epigenetic influences that alter the epigenome, when passed on to offspring, can increase their risk of developing an altered metabolic profile. This review is focused on the role of paternal inheritance as demonstrated by clinical, epidemiological, and experimental models. Development of additional experimental models that resemble the specific epigenetic sensitive situations in human studies will be essential to explore paternally induced trans-generational effects that are mediated, primarily, by epigenetic effects. Further elucidation of epigenetic marks will help identify preventive and therapeutic targets, which in combination with healthy lifestyle choices, can diminish the growing tide of obesity, type 2 diabetes, and other related disorders.
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Affiliation(s)
- Yuriy Slyvka
- Department of Biomedical Sciences, HCOM, Ohio University, Athens, OH, 45701, USA
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Geoghegan JL, Spencer HG. The evolutionary potential of paramutation: A population-epigenetic model. Theor Popul Biol 2013; 88:9-19. [DOI: 10.1016/j.tpb.2013.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 05/16/2013] [Indexed: 10/26/2022]
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Abstract
The heritability of specific phenotypical traits relevant for physical performance has been extensively investigated and discussed by experts from various research fields. By deciphering the complete human DNA sequence, the human genome project has provided impressive insights into the genomic landscape. The hope that this information would reveal the origin of phenotypical traits relevant for physical performance or disease risks has proven overly optimistic, and it is still premature to refer to a 'post-genomic' era of biological science. Linking genomic regions with functions, phenotypical traits and variation in disease risk is now a major experimental bottleneck. The recent deluge of genome-wide association studies (GWAS) generates extensive lists of sequence variants and genes potentially linked to phenotypical traits, but functional insight is at best sparse. The focus of this review is on the complex mechanisms that modulate gene expression. A large fraction of these mechanisms is integrated into the field of epigenetics, mainly DNA methylation and histone modifications, which lead to persistent effects on the availability of DNA for transcription. With the exceptions of genomic imprinting and very rare cases of epigenetic inheritance, epigenetic modifications are not inherited transgenerationally. Along with their susceptibility to external influences, epigenetic patterns are highly specific to the individual and may represent pivotal control centers predisposing towards higher or lower physical performance capacities. In that context, we specifically review how epigenetics combined with classical genetics could broaden our knowledge of genotype-phenotype interactions. We discuss some of the shortcomings of GWAS and explain how epigenetic influences can mask the outcome of quantitative genetic studies. We consider epigenetic influences, such as genomic imprinting and epigenetic inheritance, as well as the life-long variability of epigenetic modification patterns and their potential impact on phenotype with special emphasis on traits related to physical performance. We suggest that epigenetic effects may also play a considerable role in the determination of athletic potential and these effects will need to be studied using more sophisticated quantitative genetic models. In the future, epigenetic status and its potential influence on athletic performance will have to be considered, explored and validated using well controlled model systems before we can begin to extrapolate new findings to complex and heterogeneous human populations. A combination of the fields of genomics, epigenomics and transcriptomics along with improved bioinformatics tools and precise phenotyping, as well as a precise classification of the test populations is required for future research to better understand the inter-relations of exercise physiology, performance traits and also susceptibility towards diseases. Only this combined input can provide the overall outlook necessary to decode the molecular foundation of physical performance.
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Affiliation(s)
- Tobias Ehlert
- Johannes Gutenberg-Universität Mainz, Department of Sports Medicine, Disease Prevention and Rehabilitation, Mainz, Germany
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Testa CM. Key issues in essential tremor genetics research: Where are we now and how can we move forward? TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2013; 3. [PMID: 23450143 PMCID: PMC3582856 DOI: 10.7916/d8q23z0z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 12/04/2012] [Indexed: 01/06/2023]
Abstract
Background Genetics research is an avenue towards understanding essential tremor (ET). Advances have been made in genetic linkage and association: there are three reported ET susceptibility loci, and mixed but growing data on risk associations. However, causal mutations have not been forthcoming. This disappointing lack of progress has opened productive discussions on challenges in ET and specifically ET genetics research, including fundamental assumptions in the field. Methods This article reviews the ET genetics literature, results to date, the open questions in ET genetics and the current challenges in addressing them. Results Several inherent ET features complicate genetic linkage and association studies: high potential phenocopy rates, inaccurate tremor self-reporting, and ET misdiagnoses are examples. Increasing use of direct examination data for subjects, family members, and controls is one current response. Smaller moves towards expanding ET phenotype research concepts into non-tremor features, clinically disputed ET subsets, and testing phenotype features instead of clinical diagnosis against genetic data are gradually occurring. The field has already moved to considering complex trait mechanisms requiring detection of combinations of rare genetic variants. Hypotheses may move further to consider novel mechanisms of inheritance, such as epigenetics. Discussion It is an exciting time in ET genetics as investigators start moving past assumptions underlying both phenotype and genetics experimental contributions, overcoming challenges to collaboration, and engaging the ET community. Multicenter collaborative efforts comprising rich longitudinal prospective phenotype data and neuropathologic analysis combined with the latest in genetics experimental design and technology will be the next wave in the field.
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Affiliation(s)
- Claudia M Testa
- Virginia Commonwealth University, Parkinson's and Movement Disorders Center, Richmond Virginia, USA
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Xu Z, Lefevre GM, Felsenfeld G. Chromatin structure, epigenetic mechanisms and long-range interactions in the human insulin locus. Diabetes Obes Metab 2012; 14 Suppl 3:1-11. [PMID: 22928559 PMCID: PMC6398329 DOI: 10.1111/j.1463-1326.2012.01645.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Regulation of gene expression in eukaryotes is largely dependent on variations in chromatin structure. More recently, it has become clear that this may involve not only local chromatin organization but also distant regulatory elements that participate in large-scale chromatin architecture within the nucleus. We describe recent methods that make possible the detection of such structures and apply them to analysis of the human insulin (INS) locus in pancreatic islets. We show that the INS gene is part of an extended 'open' chromatin domain that includes adjacent genes as well. We also find that in islets, the INS promoter is in physical contact with distant sites on the same human chromosome and notably, with the SYT8 gene, located nearly 300 kb away. The strength of the contact between INS and SYT8 is increased by glucose, and this results in stimulation of SYT8 expression. Inhibition of INS transcription decreases SYT8 expression. Furthermore, downregulation of SYT8 results in decreased secretion of insulin. Our results thus establish the existence of a regulatory network between the INS gene and other distant genes through long-range physical interactions, and suggest that such networks may have general importance for insulin biology and diabetes.
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Affiliation(s)
- Z Xu
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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Phenocopies in families with essential tremor and restless legs syndrome challenge Mendelian laws. Epigenetics might provide answers. Parkinsonism Relat Disord 2012; 18:711-6. [PMID: 22521244 DOI: 10.1016/j.parkreldis.2012.03.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 03/13/2012] [Accepted: 03/19/2012] [Indexed: 01/31/2023]
Abstract
Essential Tremor (ET) and Restless Legs Syndrome (RLS) are both highly heritable neurological disorders. The frequent occurrence of multi-incident families suggests the existence of highly penetrant alleles. However, linkage analyses and positional cloning approaches performed within the last 10 years essentially failed to identify responsible mutations. Several loci were found, but their relevance was questioned given the occurrence of suspected phenocopies in many of those families. Remarkably, in some ET and RLS families with an apparent autosomal dominant mode of transmission, the proportion of affected individuals was higher than the expected 50% and therefore suggests a non-mendelian inheritance in some cases. In fact, there is increasing evidence that epigenetic modifications, which refer to changes in gene expression without changes in DNA sequence, can be transmitted to the next generation. Moreover, epigenetic information can be transferred from one allele of a gene to the other allele of the same gene; if then inherited to the next generation, the offspring consequently presents phenotypic properties related to the untransmitted allele. This phenomenon known as paramutation is well documented in plants and has recently been shown to occur also in mammals. Here, I explore the possibility that it is the epigenetic and not only the genetic state which confers disease risk in families. Inheritance of epigenetic mutations along with paramutational events have the potential to explain the non-mendelian features in the genetics of both diseases.
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Pilu R. Paramutation: just a curiosity or fine tuning of gene expression in the next generation? Curr Genomics 2011; 12:298-306. [PMID: 22131875 PMCID: PMC3131737 DOI: 10.2174/138920211795860099] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 04/12/2011] [Accepted: 04/12/2011] [Indexed: 12/31/2022] Open
Abstract
Gene silencing is associated with heritable changes in gene expression which occur without changes in DNA sequence. In eukaryotes these phenomena are common and control important processes, such as development, imprinting, viral and transposon sequence silencing, as well as transgene silencing. Among the epigenetic events, paramutation occurs when a silenced allele (named paramutagenic) is able to silence another allele (paramutable) in trans and this change is heritable. The silenced paramutable allele acquires paramutagenic capacity in the next generations. In the 1950s, Alexander Brink described for the first time the phenomenon of paramutation, occurring in maize at the colored1 (r1) gene, a complex locus (encoding myc-homologous transcription factors) that regulates the anthocyanin biosynthetic pathway. Since then, paramutation and paramutation-like interactions have been discovered in other plants and animals, suggesting that they may underlie important mechanisms for gene expression. The molecular bases of these phenomena are unknown. However in some cases, the event of paramutation has been correlated with changes in DNA methylation, chromatin structure and recently several studies suggest that RNA could play a fundamental role. This last consideration is greatly supported by genetic screening for mutants inhibiting paramutation, which allowed the identification of genes involved in RNA-directed transcriptional silencing, although it is possible that proteins are also required for paramutation.The meaning of paramutation in the life cycle and in evolution remains to be determined even though we might conjecture that this phenomenon could be involved in a fast heritability of favourable epigenetic states across generations in a non-Mendelian way.
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Affiliation(s)
- Roberto Pilu
- Dipartimento di Produzione Vegetale, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy
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El-Ella SSA, Shaltout A, Tawfik MA, Deeb M, EL-Lahony DM, Khatab ES, Barseem NF. Non HLA genetic markers association with type-1 diabetes mellitus. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2011. [DOI: 10.1016/j.ejmhg.2011.02.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Chung HR, Yang SW, Shin CH, Park KS, Lee YA, Kim JH, Lee SH, Kim JH. The association of variable number of tandem repeats of the insulin gene with susceptibility to type 1 diabetes among Korean subjects. Diabetes Metab Res Rev 2010; 26:474-80. [PMID: 20607677 DOI: 10.1002/dmrr.1103] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND There is ethnic variation in the variable number of tandem repeats of the insulin gene (INS VNTR), one of the susceptibility loci for developing type 1 diabetes (T1D). We evaluated the influence of the genotypes and subdivisions of INS VNTR on the development of T1D in Korean subjects. METHODS The study included 352 Korean patients, under the age of 18 years who were diagnosed as having T1D, and 356 control subjects. The insulin - 23HphI A/T single nucleotide polymorphism was used as a marker of class I and III alleles. Surrounding polymorphisms at nucleotide positions + 1127, + 1140, + 2331 and + 2336 were determined as subdivisions of INS VNTR. RESULTS Classes I/I, I/III and III/III were observed at frequencies of 95.8, 4.2 and 0% among all subjects, respectively. Class I/III genotype was significantly less frequent in patients with T1D than in controls (2.56 versus 5.90%; odds ratio 0.419; P = 0.039). In a subdivision analysis, the ID/ID genotype was decreased among patients (P = 0.017, adjusted P = 0.085) and the IC allele tended to increase. The frequency of the class I/III genotype was significantly lower among patients who were diagnosed when younger than 7 years of age than in controls (odds ratio 0.115; P = 0.011). CONCLUSIONS INS VNTR has predominance of class I over class III alleles and is associated with susceptibility to T1D in Koreans. In addition, INS VNTR shows distinctive susceptibility according to the age at the onset of T1D.
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Affiliation(s)
- Hye Rim Chung
- Department of Pediatrics, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
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Thayer TC, Wilson SB, Mathews CE. Use of nonobese diabetic mice to understand human type 1 diabetes. Endocrinol Metab Clin North Am 2010; 39:541-61. [PMID: 20723819 PMCID: PMC2925291 DOI: 10.1016/j.ecl.2010.05.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In 1922, Leonard Thompson received the first injections of insulin prepared from the pancreas of canine test subjects. From pancreatectomized dogs to the more recent development of animal models that spontaneously develop autoimmune syndromes, animal models have played a meaningful role in furthering diabetes research. Of these animals, the nonobese diabetic (NOD) mouse is the most widely used for research in type 1 diabetes (T1D) because the NOD shares several genetic and immunologic traits with the human form of the disease. In this article, the authors discuss the similarities and differences in NOD and human T1D and the potential role of NOD mice in future preclinical studies, aiming to provide a better understanding of the genetic and immune defects that lead to T1D.
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Affiliation(s)
- Terri C Thayer
- Department of Pathology, Immunology, and Laboratory Medicine, The University of Florida College of Medicine, Gainesville, FL 32610, USA
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Raha O, Chowdhury S, Dasgupta S, Raychaudhuri P, Sarkar BN, Raju PV, Rao VR. Approaches in type 1 diabetes research: A status report. Int J Diabetes Dev Ctries 2010; 29:85-101. [PMID: 20142874 PMCID: PMC2812756 DOI: 10.4103/0973-3930.53126] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Accepted: 05/29/2009] [Indexed: 12/18/2022] Open
Abstract
Type 1 diabetes is a multifactorial disease with an early age of onset, in which the insulin producing beta cell of the pancreas are destroyed because of autoimmunity. It is the second most common chronic disease in children and account for 5% to 10% of all diagnosed cases of diabetes. India is having an incidence of 10.6 cases/year/100,000, and recent studies indicate that the prevalence of type 1 diabetes in India is increasing. However in view of poor health care network, there is no monitoring system in the country. Of the 18 genomic intervals implicated for the risk to develop type 1 diabetes, the major histocompatibility complex (MHC) region on chromosome 6p21.31 has been the major contributor estimated to account for 40-50%, followed by 10% frequency of INS-VNTR at 5' flanking region of the insulin gene on chromosome 11p15.5. However, population studies suggest that > 95% of type 1 diabetes have HLA-DR3 or DR4, or both, and in family studies, sibling pairs affected with type 1 diabetes have a non-random distribution of shared HLA haplotypes. As predisposing genetic factors such as HLA alleles are known, immunological interventions to prevent type 1 diabetes are of great interest. In the present study we have reviewed the status of molecular genetics of the disease and the approaches that need to be adopted in terms of developing patient and suitable control cohorts in the country.
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Affiliation(s)
- Oindrila Raha
- Anthropological Survey of India, 27-Jawaharlal Nehru Road, Kolkata, West-Bengal - 700 016, India
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Trang SH, Joyner DE, Damron TA, Aboulafia AJ, Randall RL. Potential for functional redundancy in EGF and TGFalpha signaling in desmoid cells: a cDNA microarray analysis. Growth Factors 2010; 28:10-23. [PMID: 20092031 DOI: 10.3109/08977190903299387] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Genes that replace or duplicate the function of other genes are considered functionally redundant. In this cDNA microarray study, using an Agilent microarray platform and GeneSifter analysis software, we evaluated (1) the degree of downstream transcriptional redundancy and (2) the level of genetic uniqueness apparent in desmoid tumor cells stimulated in vitro for 3 h or for 24 h with 100 ng/ml of exogenous recombinant human EGF (rhEGF) or with recombinant human transforming growth factor alpha (rhTGFalpha). Our intent was to identify genes costimulated, or genes unique to, desmoid cells stimulated in vitro with rhEGF and rhTGFalpha. This experimental approach demonstrated a 55% transcriptional redundancy in the number of desmoid genes significantly upregulated or downregulated following 3 h of stimulation with rhEGF or with rhTGFalpha, and a 65% transcriptional redundancy following 24 h of growth factor stimulation. Approximately 150 genes costimulated by rhEGF and rhTGFalpha were identified. This study suggests that EGF and TGFalpha retain some level of functional redundancy, possibly resulting from their divergence from a common ancestral gene.
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Affiliation(s)
- Sylvia H Trang
- SARC Laboratory, Sarcoma Services, Department of Orthopaedics and Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
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Wallace C, Smyth DJ, Maisuria-Armer M, Walker NM, Todd JA, Clayton DG. The imprinted DLK1-MEG3 gene region on chromosome 14q32.2 alters susceptibility to type 1 diabetes. Nat Genet 2010; 42:68-71. [PMID: 19966805 PMCID: PMC2820243 DOI: 10.1038/ng.493] [Citation(s) in RCA: 244] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2009] [Accepted: 10/08/2009] [Indexed: 12/15/2022]
Abstract
Genome-wide association (GWA) studies to map common disease susceptibility loci have been hugely successful, with over 300 reproducibly associated loci reported to date. However, these studies have not yet provided convincing evidence for any susceptibility locus subject to parent-of-origin effects. Using imputation to extend existing GWA datasets, we have obtained robust evidence at rs941576 for paternally inherited risk of type 1 diabetes (T1D; ratio of allelic effects for paternal versus maternal transmissions = 0.75; 95% confidence interval (CI) = 0.71-0.79). This marker is in the imprinted region of chromosome 14q32.2, which contains the functional candidate gene DLK1. Our meta-analysis also provided support at genome-wide significance for a T1D locus at chromosome 19p13.2. The highest association was at marker rs2304256 (odds ratio (OR) = 0.86; 95%CI = 0.82-0.90) in the TYK2 gene, which has previously been associated with systemic lupus erythematosus and multiple sclerosis.
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Affiliation(s)
- Chris Wallace
- Juvenile Diabetes Research Foundation/Wellcome Trust Diabetes and Inflammation Laboratory, Department of Medical Genetics, Cambridge Institute for Medical Research, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK
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Suter CM, Martin DIK. Paramutation: the tip of an epigenetic iceberg? Trends Genet 2010; 26:9-14. [PMID: 19945764 PMCID: PMC3137459 DOI: 10.1016/j.tig.2009.11.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Revised: 11/04/2009] [Accepted: 11/04/2009] [Indexed: 11/21/2022]
Abstract
Paramutation describes the transfer of an acquired epigenetic state to an unlinked homologous locus, resulting in a meiotically heritable alteration in gene expression. Early investigations of paramutation characterized a mode of change and inheritance distinct from mendelian genetics, catalyzing the concept of the epigenome. Numerous examples of paramutation and paramutation-like phenomena have now emerged, with evidence that implicates small RNAs in the transfer and maintenance of epigenetic states. In animals Piwi-interacting RNA (piRNA)-mediated retrotransposon suppression seems to drive a vast system of epigenetic inheritance with paramutation-like characteristics. The classic examples of paramutation might be merely informative aberrations of pervasive and broadly conserved mechanisms that use RNA to sense homology and target epigenetic modification. When viewed in this context, paramutation is only one aspect of a common and broadly distributed form of inheritance based on epigenetic states.
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Affiliation(s)
- Catherine M Suter
- Victor Chang Cardiac Research Institute, 405 Liverpool St, Darlinghurst, Sydney, NSW 2010, Australia.
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Murine pancreatic beta TC3 cells show greater 2', 5'-oligoadenylate synthetase (2'5'AS) antiviral enzyme activity and apoptosis following IFN-alpha or poly(I:C) treatment than pancreatic alpha TC3 cells. EXPERIMENTAL DIABETES RESEARCH 2009; 2009:631026. [PMID: 19888425 PMCID: PMC2771153 DOI: 10.1155/2009/631026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 06/30/2009] [Accepted: 08/06/2009] [Indexed: 12/15/2022]
Abstract
Type 1 diabetes is caused by autoimmune destruction of pancreatic beta cells, possibly virus initiated. Virus infection induces alpha-interferon (IFN-α), leading to upregulation of genes encoding double-stranded (ds) RNA-dependent antiviral enzymes 2′, 5′-oligoadenylate synthetase (2′5′AS) and PKR (p68). To investigate whether beta cell specificity could be due to antiviral differences between beta and alpha cells, we treated beta and alpha TC3 cell lines with IFN-α and/or poly(I:C) (a synthetic dsRNA). Results showed that, following IFN-α stimulation, increases in 2′5′AS levels and activities were significantly higher in beta than alpha cells (P < .001), whereas increases in PKR level and activity were comparable in the two cell types. Poly(I:C) stimulated 2′5′AS activity in beta but not alpha cells, and co-transfection IFN-α
plus poly(I:C) induced apoptosis in beta but not alpha cells. These findings suggest that the elevated 2′5′AS response of pancreatic beta cells could render them particularly vulnerable to damage and/or apoptosis during virus infection.
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Ferguson LA, Docherty HM, MacKenzie AE, Docherty K. An engineered zinc finger protein reveals a role for the insulin VNTR in the regulation of the insulin and adjacent IGF2 genes. FEBS Lett 2009; 583:3181-6. [PMID: 19733567 DOI: 10.1016/j.febslet.2009.08.041] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 08/05/2009] [Accepted: 08/29/2009] [Indexed: 01/27/2023]
Abstract
An engineered zinc finger protein (eZFP) was isolated from a library based on its ability to activate expression of the endogenous insulin gene in HEK-293 cells. Using a panel of insulin promoter constructs, the eZFP was shown to act through the variable number of tandem repeat (VNTR) region located 365 base pairs upstream of the transcription start site. The eZFP also activated expression of the IGF2 gene that lies close to INS on chromosome 11p15. These results demonstrate that the INSVNTR controls expression of the insulin and IGF2 genes and provide a mechanistic explanation for previous studies that demonstrated an association between INSVNTR genotypes and placental levels of IGF2.
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Affiliation(s)
- Laura A Ferguson
- School of Medical Sciences, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
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Jablonka E, Raz G. Transgenerational epigenetic inheritance: prevalence, mechanisms, and implications for the study of heredity and evolution. QUARTERLY REVIEW OF BIOLOGY 2009; 84:131-76. [PMID: 19606595 DOI: 10.1086/598822] [Citation(s) in RCA: 812] [Impact Index Per Article: 54.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
This review describes new developments in the study of transgenerational epigenetic inheritance, a component of epigenetics. We start by examining the basic concepts of the field and the mechanisms that underlie epigenetic inheritance. We present a comprehensive review of transgenerational cellular epigenetic inheritance among different taxa in the form of a table, and discuss the data contained therein. The analysis of these data shows that epigenetic inheritance is ubiquitous and suggests lines of research that go beyond present approaches to the subject. We conclude by exploring some of the consequences of epigenetic inheritance for the study of evolution, while also pointing to the importance of recognizing and understanding epigenetic inheritance for practical and theoretical issues in biology.
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Affiliation(s)
- Eva Jablonka
- The Cohn Institute for the History and Philosophy of Science and Ideas, Tel-Aviv University, Tel-Aviv 69978, Israel.
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Benedek G, Brautbar C, Vardi P, Sharon N, Weintrob N, Zung A, Israel S. Effect of polymorphism in insulin locus and HLA on type 1 diabetes in four ethnic groups in Israel. ACTA ACUST UNITED AC 2009; 73:33-8. [DOI: 10.1111/j.1399-0039.2008.01153.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Liu H, Huang J, Wang J, Jiang S, Bailey AS, Goldman DC, Welcker M, Bedell V, Slovak ML, Clurman B, Thayer M, Fleming WH, Epner E. Transvection mediated by the translocated cyclin D1 locus in mantle cell lymphoma. ACTA ACUST UNITED AC 2008; 205:1843-58. [PMID: 18625744 PMCID: PMC2525596 DOI: 10.1084/jem.20072102] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In mantle cell lymphoma (MCL) and some cases of multiple myeloma (MM), cyclin D1 expression is deregulated by chromosome translocations involving the immunoglobulin heavy chain (IgH) locus. To evaluate the mechanisms responsible, gene targeting was used to study long-distance gene regulation. Remarkably, these targeted cell lines lost the translocated chromosome (t(11;14)). In these MCL and MM cells, the nonrearranged cyclin D1 (CCND1) locus reverts from CpG hypomethylated to hypermethylated. Reintroduction of the translocated chromosome induced a loss of methylation at the unrearranged CCND1 locus, providing evidence of a transallelic regulatory effect. In these cell lines and primary MCL patient samples, the CCND1 loci are packaged in chromatin-containing CCCTC binding factor (CTCF) and nucleophosmin (NPM) at the nucleolus. We show that CTCF and NPM are bound at the IgH 3′ regulatory elements only in the t(11;14) MCL cell lines. Furthermore, NPM short hairpin RNA produces a specific growth arrest in these cells. Our data demonstrate transvection in human cancer and suggest a functional role for CTCF and NPM.
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Affiliation(s)
- Hui Liu
- Center for Hematologic Malignancies, Oregon Cancer Institute, Portland, OR 97239, USA
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Bonifacio E, Pflüger M, Marienfeld S, Winkler C, Hummel M, Ziegler AG. Maternal type 1 diabetes reduces the risk of islet autoantibodies: relationships with birthweight and maternal HbA(1c). Diabetologia 2008; 51:1245-52. [PMID: 18463843 DOI: 10.1007/s00125-008-1022-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Accepted: 04/04/2008] [Indexed: 01/10/2023]
Abstract
AIMS/HYPOTHESIS The risk of type 1 diabetes is reduced in the children of mothers with type 1 diabetes compared with children of fathers with type 1 diabetes. We asked whether children of mothers with type 1 diabetes also have a decreased risk of developing islet autoantibodies, and which factors associated with maternal diabetes contribute to a reduced islet autoantibody risk in offspring. METHODS Singleton offspring of a mother (n = 1,008) or father with type 1 diabetes (n = 578) from the BABYDIAB study were included. Children were followed from birth for the development of islet autoantibodies defined as two or more autoantibodies to insulin, glutamic acid decarboxylase or insulinoma antigen 2 in two or more blood samples. RESULTS Islet autoantibody risk was lower in children of mothers with type 1 diabetes (5 year risk, 3.2% vs 5.7% in children of fathers with type 1 diabetes; p = 0.04). Among factors that differed between pregnancies from mothers with and without type 1 diabetes, birthweight was associated with islet autoantibody risk. Risk was reduced in children with birthweights in the lower (adjusted HR 0.33; 95% CI 0.14-0.75; p = 0.009) and upper (HR 0.45; 95% CI 0.21-0.97; p = 0.04) tertiles compared with the middle tertile. A sub-analysis of maternal HbA(1c) suggested that moderately elevated third trimester maternal HbA(1c) was also associated with a reduced islet autoantibody risk in children of mothers with type 1 diabetes (5.7-7%; HR 0.38; 95% CI 0.15-0.96; p = 0.04 vs children of mothers with HbA(1c) < 5.7%). CONCLUSIONS/INTERPRETATION The risk of islet autoimmunity is modified by maternally influenced events such as birthweight.
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Affiliation(s)
- E Bonifacio
- Diabetes Research Institute, Kölner Platz 1, D-80804, Munich, Germany
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Abstract
Using the compiled human genome sequence, we systematically cataloged all tandem repeats with periods between 20 and 2000 bp and defined two subsets whose consensus sequences were found at either single-locus tandem repeats (slTRs) or multilocus tandem repeats (mlTRs). Parameters compiled for these subsets provide insights into mechanisms underlying the creation and evolution of tandem repeats. Both subsets of tandem repeats are nonrandomly distributed in the genome, being found at higher frequency at many but not all chromosome ends and internal clusters of mlTRs were also observed. Despite the integral role of recombination in the biology of tandem repeats, recombination hotspots colocalized only with shorter microsatellites and not the longer repeats examined here. An increased frequency of slTRs was observed near imprinted genes, consistent with a functional role, while both slTRs and mlTRs were found more frequently near genes implicated in triplet expansion diseases, suggesting a general instability of these regions. Using our collated parameters, we identified 2230 slTRs as candidates for highly informative molecular markers.
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Rassoulzadegan M, Grandjean V, Gounon P, Cuzin F. Sperm RNA, an "epigenetic rheostat" of gene expression? ACTA ACUST UNITED AC 2008; 53:235-8. [PMID: 18309895 DOI: 10.1080/01485010701569916] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Cuzin F, Grandjean V, Rassoulzadegan M. Inherited variation at the epigenetic level: paramutation from the plant to the mouse. Curr Opin Genet Dev 2008; 18:193-6. [DOI: 10.1016/j.gde.2007.12.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Accepted: 12/19/2007] [Indexed: 10/22/2022]
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Paramutation-Like Effects at the Mouse scapinin (Phactr3) Locus. J Mol Biol 2008; 377:605-8. [DOI: 10.1016/j.jmb.2008.01.062] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Revised: 01/14/2008] [Accepted: 01/16/2008] [Indexed: 10/22/2022]
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Genomic imprinting and human psychology: cognition, behavior and pathology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 626:71-88. [PMID: 18372792 DOI: 10.1007/978-0-387-77576-0_6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Imprinted genes expressed in the brain are numerous and it has become clear that they play an important role in nervous system development and function. The significant influence of genomic imprinting during development sets the stage for structural and physiological variations affecting psychological function and behaviour, as well as other physiological systems mediating health and well-being. However, our understanding of the role of imprinted genes in behaviour lags far behind our understanding of their roles in perinatal growth and development. Knowledge of genomic imprinting remains limited among behavioral scientists and clinicians and research regarding the influence of imprinted genes on normal cognitive processes and the most common forms of neuropathology has been limited to date. In this chapter, we will explore how knowledge of genomic imprinting can be used to inform our study of normal human cognitive and behavioral processes as well as their disruption. Behavioural analyses of rare imprinted disorders, such as Prader-Willi and Angelman syndromes, provide insight regarding the phenotypic impact of imprinted genes in the brain, and can be used to guide the study of normal behaviour as well as more common but etiologically complex disorders such as ADHD and autism. Furthermore, hypotheses regarding the evolutionary development of imprinted genes can be used to derive predictions about their role in normal behavioural variation, such as that observed in food-related and social interactions.
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Liblau R, Cassan C. Tolérance immunitaire vis-à-vis d’auto-antigènes du système nerveux : implications thérapeutiques. Rev Neurol (Paris) 2007. [DOI: 10.1016/s0035-3787(07)92155-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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