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Ihnatovych I, Saddler RA, Sule N, Szigeti K. Translational implications of CHRFAM7A, an elusive human-restricted fusion gene. Mol Psychiatry 2024; 29:1020-1032. [PMID: 38200291 PMCID: PMC11176066 DOI: 10.1038/s41380-023-02389-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 12/08/2023] [Accepted: 12/15/2023] [Indexed: 01/12/2024]
Abstract
Genes restricted to humans may contribute to human-specific traits and provide a different context for diseases. CHRFAM7A is a uniquely human fusion gene and a negative regulator of the α7 nicotinic acetylcholine receptor (α7 nAChR). The α7 nAChR has been a promising target for diseases affecting cognition and higher cortical functions, however, the treatment effect observed in animal models failed to translate into human clinical trials. As CHRFAM7A was not accounted for in preclinical drug screens it may have contributed to the translational gap. Understanding the complex genetic architecture of the locus, deciphering the functional impact of CHRFAM7A on α7 nAChR neurobiology and utilizing human-relevant models may offer novel approaches to explore α7 nAChR as a drug target.
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Affiliation(s)
- Ivanna Ihnatovych
- Department of Neurology, State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Ruth-Ann Saddler
- Department of Neurology, State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Norbert Sule
- Roswell Park Comprehensive Cancer Center, 665 Elm St, Buffalo, NY, 14203, USA
| | - Kinga Szigeti
- Department of Neurology, State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA.
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He J, Li Q, Zhang Q. rvTWAS: identifying gene-trait association using sequences by utilizing transcriptome-directed feature selection. Genetics 2024; 226:iyad204. [PMID: 38001381 DOI: 10.1093/genetics/iyad204] [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: 10/20/2023] [Revised: 11/14/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023] Open
Abstract
Toward the identification of genetic basis of complex traits, transcriptome-wide association study (TWAS) is successful in integrating transcriptome data. However, TWAS is only applicable for common variants, excluding rare variants in exome or whole-genome sequences. This is partly because of the inherent limitation of TWAS protocols that rely on predicting gene expressions. Our previous research has revealed the insight into TWAS: the 2 steps in TWAS, building and applying the expression prediction models, are essentially genetic feature selection and aggregations that do not have to involve predictions. Based on this insight disentangling TWAS, rare variants' inability of predicting expression traits is no longer an obstacle. Herein, we developed "rare variant TWAS," or rvTWAS, that first uses a Bayesian model to conduct expression-directed feature selection and then uses a kernel machine to carry out feature aggregation, forming a model leveraging expressions for association mapping including rare variants. We demonstrated the performance of rvTWAS by thorough simulations and real data analysis in 3 psychiatric disorders, namely schizophrenia, bipolar disorder, and autism spectrum disorder. We confirmed that rvTWAS outperforms existing TWAS protocols and revealed additional genes underlying psychiatric disorders. Particularly, we formed a hypothetical mechanism in which zinc finger genes impact all 3 disorders through transcriptional regulations. rvTWAS will open a door for sequence-based association mappings integrating gene expressions.
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Affiliation(s)
- Jingni He
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary T2N 1N4, Canada
| | - Qing Li
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary T2N 1N4, Canada
| | - Qingrun Zhang
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary T2N 1N4, Canada
- Department of Mathematics and Statistics, University of Calgary, Calgary T2N 1N4, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary T2N 1N4, Canada
- Arnie Charbonneau Cancer Institute, University of Calgary, Calgary T2N 1N4, Canada
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Leonard S, Benfante R. Unanswered questions in the regulation and function of the duplicated α7 nicotinic receptor gene CHRFAM7A. Pharmacol Res 2023; 192:106783. [PMID: 37164281 DOI: 10.1016/j.phrs.2023.106783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/20/2023] [Accepted: 04/30/2023] [Indexed: 05/12/2023]
Abstract
The α7 nicotinic receptor (α7 nAChR) is an important entry point for Ca2+ into the cell, which has broad and important effects on gene expression and function. The gene (CHRNA7), mapping to chromosome (15q14), has been genetically linked to a large number of diseases, many of which involve defects in cognition. While numerous mutations in CHRNA7 are associated with mental illness and inflammation, an important control point may be the function of a recently discovered partial duplication CHRNA7, CHRFAM7A, that negatively regulates the function of the α7 receptor, through the formation of heteropentamers; other functions cannot be excluded. The deregulation of this human specific gene (CHRFAM7A) has been linked to neurodevelopmental, neurodegenerative, and inflammatory disorders and has important copy number variations. Much effort is being made to understand its function and regulation both in healthy and pathological conditions. However, many questions remain to be answered regarding its functional role, its regulation, and its role in the etiogenesis of neurological and inflammatory disorders. Missing knowledge on the pharmacology of the heteroreceptor has limited the discovery of new molecules capable of modulating its activity. Here we review the state of the art on the role of CHRFAM7A, highlighting unanswered questions to be addressed. A possible therapeutic approach based on genome editing protocols is also discussed.
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Affiliation(s)
- Sherry Leonard
- Department of Psychiatry - University of Colorado Anschutz, Aurora, Colorado, USA
| | - Roberta Benfante
- CNR - Institute of Neuroscience, Vedano al Lambro (MB), Italy; Dept. Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy; NeuroMI - Milan Center for Neuroscience, University of Milano Bicocca, Milan, Italy.
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Courties A, Olmer M, Myers K, Ordoukhanian P, Head SR, Natarajan P, Berenbaum F, Sellam J, Lotz MK. Human-specific duplicate CHRFAM7A gene is associated with more severe osteoarthritis and amplifies pain behaviours. Ann Rheum Dis 2023; 82:710-718. [PMID: 36627169 PMCID: PMC10101906 DOI: 10.1136/ard-2022-223470] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 12/28/2022] [Indexed: 01/12/2023]
Abstract
OBJECTIVES CHRFAM7A is a uniquely human fusion gene that functions as a dominant negative regulator of alpha 7 acetylcholine nicotinic receptor (α7nAChR) in vitro. This study determined the impact of CHRFAM7A on α7nAChR agonist responses, osteoarthritis (OA) severity and pain behaviours and investigated mechanisms. METHODS Transgenic CHRFAM7A (TgCHRFAM7A) mice were used to determine the impact of CHRFAM7A on knee OA histology, pain severity in OA and other pain models, response to nAchR agonist and IL-1β. Mouse and human cells were used for mechanistic studies. RESULTS Transgenic (Tg) TgCHRFAM7A mice developed more severe structural damage and increased mechanical allodynia than wild type (WT) mice in the destabilisation of medial meniscus model of OA. This was associated with a decreased suppression of inflammation by α7nAchR agonist. TgCHRFAM7A mice displayed a higher basal sensitivity to pain stimuli and increased pain behaviour in the monoiodoacetate and formalin models. Dorsal root ganglia of TgCHRFAM7A mice showed increased macrophage infiltration and expression of the chemokine fractalkine and also had a compromised antinociceptive response to the α7nAchR agonist nicotine. Both native CHRNA7 and CHRFAM7A subunits were expressed in human joint tissues and the CHRFAM7A/CHRNA7 ratio was increased in OA cartilage. Human chondrocytes with two copies of CHRFAM7A had reduced anti-inflammatory responses to nicotine. CONCLUSION CHRFAM7A is an aggravating factor for OA-associated inflammation and tissue damage and a novel genetic risk factor and therapeutic target for pain.
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Affiliation(s)
- Alice Courties
- Department of Molecular Medicine, Scripps Research, La Jolla, California, USA
- INSERM UMRS 938, Hôpital Saint-Antoine, Service de rhumatologie, AP-HP, Sorbonne Université, Paris, France
| | - Merissa Olmer
- Department of Molecular Medicine, Scripps Research, La Jolla, California, USA
| | - Kevin Myers
- Department of Molecular Medicine, Scripps Research, La Jolla, California, USA
| | - Phillip Ordoukhanian
- Center for Computational Biology & Bioinformatics and Genomics Core, Scripps Research, La Jolla, California, USA
| | - Steven R Head
- Center for Computational Biology & Bioinformatics and Genomics Core, Scripps Research, La Jolla, California, USA
| | - Padmaja Natarajan
- Center for Computational Biology & Bioinformatics and Genomics Core, Scripps Research, La Jolla, California, USA
| | - Francis Berenbaum
- INSERM UMRS 938, Hôpital Saint-Antoine, Service de rhumatologie, AP-HP, Sorbonne Université, Paris, France
| | - Jérémie Sellam
- INSERM UMRS 938, Hôpital Saint-Antoine, Service de rhumatologie, AP-HP, Sorbonne Université, Paris, France
| | - Martin K Lotz
- Department of Molecular Medicine, Scripps Research, La Jolla, California, USA
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Peng W, Mao L, Dang X. The emergence of the uniquely human α7 nicotinic acetylcholine receptor gene and its roles in inflammation. Gene 2022; 842:146777. [PMID: 35952843 DOI: 10.1016/j.gene.2022.146777] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/23/2022] [Accepted: 07/28/2022] [Indexed: 11/16/2022]
Abstract
The uniquely human CHRFAM7A gene is evolved from the fusion of two partially duplicated genes, ULK4 and CHRNA7. Transcription of CHRFAM7A gene produces a 1256-bp open reading frame (ORF) that encodes duplicate α7-nAChR (dup-α7-nAChR), in which a 27-aminoacid peptide derived from ULK4 gene replaces the 146-aminoacid N-terminal extracellular domain of α7-nAChR, and the rest protein domains are exactly the same as those of α7-nAChR. In vitro, dup-α7-nAChR has been shown to form hetero-pentamer with α7-nAChR and dominant-negatively inhibits the channel functions of the latter. α7-nAChR has been shown to participate in many pathophysiological processes such as cognition, memory, neuronal degenerative disease, psychological disease, and inflammatory diseases, among others, and thus has been extensively exploited as potential therapeutic targets for many diseases. Unfortunately, many lead compounds that showed potent therapeutic effect in preclinical animal models failed clinical trials, suggesting the possibility that the contribution of the uniquely human CHRFAM7A gene may not be accounted for in the preclinical research. Here, we review the emergence of CHRFAM7A gene and its transcriptional regulation, the regulatory roles of CHRFAM7A gene in α7-nAChR-mediated cholinergic anti-inflammatory pathway, and the potential implications of CHRFAM7A gene in translational research and drug discovery.
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Affiliation(s)
- Wanling Peng
- The Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, India
| | - Liang Mao
- The Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, India
| | - Xitong Dang
- The Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, India; Department of Cardiovascular Medicine, The 1st Affiliated Hospital of Southwest Medical University, Southwest Medical University, Luzhou 646000, China.
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Di Lascio S, Fornasari D, Benfante R. The Human-Restricted Isoform of the α7 nAChR, CHRFAM7A: A Double-Edged Sword in Neurological and Inflammatory Disorders. Int J Mol Sci 2022; 23:ijms23073463. [PMID: 35408823 PMCID: PMC8998457 DOI: 10.3390/ijms23073463] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/13/2022] [Accepted: 03/21/2022] [Indexed: 12/13/2022] Open
Abstract
CHRFAM7A is a relatively recent and exclusively human gene arising from the partial duplication of exons 5 to 10 of the α7 neuronal nicotinic acetylcholine receptor subunit (α7 nAChR) encoding gene, CHRNA7. CHRNA7 is related to several disorders that involve cognitive deficits, including neuropsychiatric, neurodegenerative, and inflammatory disorders. In extra-neuronal tissues, α7nAChR plays an important role in proliferation, differentiation, migration, adhesion, cell contact, apoptosis, angiogenesis, and tumor progression, as well as in the modulation of the inflammatory response through the “cholinergic anti-inflammatory pathway”. CHRFAM7A translates the dupα7 protein in a multitude of cell lines and heterologous systems, while maintaining processing and trafficking that are very similar to the full-length form. It does not form functional ion channel receptors alone. In the presence of CHRNA7 gene products, dupα7 can assemble and form heteromeric receptors that, in order to be functional, should include at least two α7 subunits to form the agonist binding site. When incorporated into the receptor, in vitro and in vivo data showed that dupα7 negatively modulated α7 activity, probably due to a reduction in the number of ACh binding sites. Very recent data in the literature report that the presence of the duplicated gene may be responsible for the translational gap in several human diseases. Here, we will review the studies that have been conducted on CHRFAM7A in different pathologies, with the intent of providing evidence regarding when and how the expression of this duplicated gene may be beneficial or detrimental in the pathogenesis, and eventually in the therapeutic response, to CHRNA7-related neurological and non-neurological diseases.
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Affiliation(s)
- Simona Di Lascio
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), Università degli Studi di Milano, 20129 Milan, Italy; (S.D.L.); (D.F.)
| | - Diego Fornasari
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), Università degli Studi di Milano, 20129 Milan, Italy; (S.D.L.); (D.F.)
- CNR Institute of Neuroscience, 20845 Vedano al Lambro, Italy
| | - Roberta Benfante
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), Università degli Studi di Milano, 20129 Milan, Italy; (S.D.L.); (D.F.)
- CNR Institute of Neuroscience, 20845 Vedano al Lambro, Italy
- NeuroMi, Milan Center for Neuroscience, University of Milano Bicocca, 20126 Milan, Italy
- Correspondence:
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Lin M, Huang W, Kabbani N, Theiss MM, Hamilton JF, Ecklund JM, Conley YP, Vodovotz Y, Brienza D, Wagner AK, Robbins E, Sowa GA, Lipsky RH. Effect of CHRFAM7A Δ2bp gene variant on secondary inflammation after spinal cord injury. PLoS One 2021; 16:e0251110. [PMID: 33956875 PMCID: PMC8101719 DOI: 10.1371/journal.pone.0251110] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 04/20/2021] [Indexed: 11/18/2022] Open
Abstract
The α7 neuronal nicotinic acetylcholine receptors (α7nAChRs) are essential for anti-inflammatory responses. The human-specific CHRFAM7A gene and its 2bp deletion polymorphism (Δ2bp variant) encodes a structurally-deficient α7nAChRs that may impact the anti-inflammatory function. We studied 45 spinal cord injury (SCI) patients for up to six weeks post SCI to investigate the role of the Δ2bp variant on multiple circulating inflammatory mediators and two outcome measures (neuropathic pain and risk of pressure ulcers). The patient's SCI were classified as either severe or mild. Missing values were imputed. Overall genetic effect was conducted with independent sample t-test and corrected with false discovery rate (FDR). Univariate analysis and regression analysis were applied to evaluate the Δ2bp effects on temporal variation of inflammatory mediators post SCI and their interaction with outcome measures. In severe SCI, the Δ2bp carriers showed higher levels of circulating inflammatory mediators than the Δ2bp non-carriers in TNF-α (FDR = 9.6x10-4), IFN-γ (FDR = 1.3x10-3), IL-13 (FDR = 1.6x10-3), CCL11 (FDR = 2.1x10-3), IL-12p70 (FDR = 2.2x10-3), IL-8 (FDR = 2.2x10-3), CXCL10 (FDR = 3.1x10-3), CCL4 (FDR = 5.7x10-3), IL-12p40 (FDR = 7.1x10-3), IL-1b (FDR = 0.014), IL-15 (FDR = 0.024), and IL-2 (FDR = 0.037). IL-8 and CCL2 were negatively associated with days post injury (DPI) for the Δ2bp carriers (P = 2x10-7 and P = 2x10-8, respectively) and IL-5 was positively associated with DPI for the Δ2bp non-carriers (P = 0.015). Neuropathic pain was marginally positively associated with IL-13 for the Δ2bp carriers (P = 0.056). In mild SCI, the Δ2bp carriers had lower circulating levels of IL-15 (FDR = 0.04) than the Δ2bp non-carriers. Temporal variation of inflammatory mediators post SCI was not associated with the Δ2bp variant. For the mild SCI Δ2bp carriers, risk of pressure ulcers was positively associated with circulating levels of IFN-γ, CXCL10, and CCL4 and negatively associated with circulating levels of IL-12p70. These findings support an important role for the human-specific CHRFAM7A Δ2bp gene variant in modifying anti-inflammatory function of α7nAChRs following SCI.
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Affiliation(s)
- Mingkuan Lin
- School of Systems Biology, George Mason University, Fairfax, Virginia, United States of America
- Inova Neuroscience and Spine Institute, Inova Health System, Falls Church, Virginia, United States of America
- * E-mail:
| | - Wan Huang
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Nadine Kabbani
- School of Systems Biology, George Mason University, Fairfax, Virginia, United States of America
| | - Mark M. Theiss
- Department of Orthopedic Services, Inova Health System, Falls Church, Virginia, United States of America
| | - John F. Hamilton
- Inova Neuroscience and Spine Institute, Inova Health System, Falls Church, Virginia, United States of America
| | - James M. Ecklund
- Inova Neuroscience and Spine Institute, Inova Health System, Falls Church, Virginia, United States of America
| | - Yvette P. Conley
- School of Nursing and Department of Human Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Yoram Vodovotz
- Department of Surgery, Center for Inflammation & Regenerative Modeling in McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - David Brienza
- Rehabilitation Science &Technology, Bioengineering, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Amy K. Wagner
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Emily Robbins
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Gwendolyn A. Sowa
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Robert H. Lipsky
- School of Systems Biology, George Mason University, Fairfax, Virginia, United States of America
- Inova Neuroscience and Spine Institute, Inova Health System, Falls Church, Virginia, United States of America
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Santos JR, Tomaz PRX, Scholz JR, Gaya PV, Abe TO, Krieger JE, Pereira AC, Santos PCJDL. Profile of the Nicotinic Cholinergic Receptor Alpha 7 Subunit Gene Expression is Associated with Response to Varenicline Treatment. Genes (Basel) 2020; 11:E746. [PMID: 32640505 PMCID: PMC7397196 DOI: 10.3390/genes11070746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 06/15/2020] [Accepted: 06/25/2020] [Indexed: 12/11/2022] Open
Abstract
INTRODUCTION Smoking is considered the leading cause of preventable morbidity and mortality worldwide. Studies have sought to identify predictors of response to smoking cessation treatments. The aim of this study was to analyze a possible association of target gene expression for smoking cessation with varenicline. METHODS We included 74 smokers starting treatment with varenicline. Gene expression analysis was performed through the custom RT² Profiler qPCR array assay, including 17 genes. Times for sample collection were before the start of therapy (T0) and two weeks (T2) and four weeks (T4) after the start of treatment. RESULTS For gene expression analysis, we selected 14 patients who had success and 13 patients resistant to varenicline treatment. Success was considered to be when a patient achieved tobacco abstinence until the fourth week of treatment and resistant was when a patient had not stopped smoking as of the fourth week of treatment. We observed a significant difference for CHRNA7 gene expression: in the resistant group, samples from T2 and T4 had lower expression compared with T0 (fold change: 0.38, P = 0.007; fold change: 0.67, P = 0.004; respectively). CONCLUSION This exploratory clinical study, searching for a possible predictor of effectiveness for varenicline, reaffirmed the association of the α7 nAChR subunit for nicotine dependence and smoking therapy effectiveness with varenicline.
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Affiliation(s)
- Juliana Rocha Santos
- Laboratory of Genetics and Molecular Cardiology, Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-904, Brazil; (J.R.S.); (P.R.X.T.); (J.E.K.); (A.C.P.)
| | - Paulo Roberto Xavier Tomaz
- Laboratory of Genetics and Molecular Cardiology, Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-904, Brazil; (J.R.S.); (P.R.X.T.); (J.E.K.); (A.C.P.)
| | - Jaqueline Ribeiro Scholz
- Smoking Cessation Program Department, Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-904, Brazil; (J.R.S.); (P.V.G.); (T.O.A.)
| | - Patrícia Viviane Gaya
- Smoking Cessation Program Department, Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-904, Brazil; (J.R.S.); (P.V.G.); (T.O.A.)
| | - Tânia Ogawa Abe
- Smoking Cessation Program Department, Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-904, Brazil; (J.R.S.); (P.V.G.); (T.O.A.)
| | - José Eduardo Krieger
- Laboratory of Genetics and Molecular Cardiology, Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-904, Brazil; (J.R.S.); (P.R.X.T.); (J.E.K.); (A.C.P.)
| | - Alexandre Costa Pereira
- Laboratory of Genetics and Molecular Cardiology, Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-904, Brazil; (J.R.S.); (P.R.X.T.); (J.E.K.); (A.C.P.)
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Jiang Y, Yuan H, Huang L, Hou X, Zhou R, Dang X. Global proteomic profiling of the uniquely human CHRFAM7A gene in transgenic mouse brain. Gene 2019; 714:143996. [PMID: 31348980 DOI: 10.1016/j.gene.2019.143996] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 07/19/2019] [Accepted: 07/22/2019] [Indexed: 01/08/2023]
Abstract
The uniquely human α7-nAChR gene (CHRFAM7A) is evolved from the fusion of two partially duplicated genes, FAM7 and α7-nAChR gene (CHRNA7), and is inserted on same chromosome 15, 5' end of the CHRNA7 gene. Transcription of CHRFAM7A gene produces a 1256-bp open reading frame encoding dup-α7-nAChR, where a 27-aminoacid residues from FAM7 replaced the 146-aminoacid residues of the N-terminal extracellular ligand binding domain of α7-nAChR. In vitro, dup-α7-nAChR has been shown to form hetero-pentamer with α7-nAChR and dominant-negatively regulates the channel functions of α7-nAChR. However, the contribution of CHRFAM7A gene to the biology of α7-nAChR in the brain in vivo remains largely a matter of conjecture. CHRFAM7A transgenic mouse was created and differentially expressed proteins were profiled from the whole brain using iTRAQ-2D-LC-MS/MS proteomic technology. Proteins with a fold change of ≥1.2 or ≤0.83 and p < 0.05 were considered to be significant. Bioinformatics analysis showed that over-expression of the CHRFAM7A gene significantly modulated the proteins commonly involved in the signaling pathways of α7-nAChR-mediated neuropsychiatric disorders including Parkinson's disease, Alzheimer's disease, Huntington's disease, and alcoholism, suggesting that the CHRFAM7A gene contributes to the pathogenesis of neuropsychiatric disorders mostly likely through fine-tuning the functions of α7-nAChR in the brain.
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Affiliation(s)
- Yu Jiang
- The Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Lab of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan 646000,China
| | - Haiyang Yuan
- The Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Lab of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan 646000,China
| | - Li Huang
- The Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Lab of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan 646000,China
| | - Xiaojie Hou
- Division of Vascular Surgery, The Affiliated Hospital of Southwest Medical University, Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Rui Zhou
- The Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Lab of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan 646000,China
| | - Xitong Dang
- The Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Lab of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan 646000,China; Division of Vascular Surgery, The Affiliated Hospital of Southwest Medical University, Southwest Medical University, Luzhou, Sichuan 646000, China.
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Alsagob M, Salih MA, Hamad MHA, Al-Yafee Y, Al-Zahrani J, Al-Bakheet A, Nester M, Sakati N, Wakil SM, AlOdaib A, Colak D, Kaya N. First report of two successive deletions on chromosome 15q13 cytogenetic bands in a boy and girl: additional data to 15q13.3 syndrome with a report of high IQ patient. Mol Cytogenet 2019; 12:21. [PMID: 31131027 PMCID: PMC6525444 DOI: 10.1186/s13039-019-0432-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 05/01/2019] [Indexed: 11/10/2022] Open
Abstract
15q13.3 syndrome is associated with a wide spectrum of neurological disorders. Among a cohort of 150 neurodevelopmental cases, we identified two patients with two close proximity interstitial hemizygous deletions on chromosome 15q13. Using high-density microarrays, we characterized these deletions and their approximate breakpoints. The second deletion in both patients overlaps in a small area containing CHRNA7 where the gene is partially deleted. The CHRNA7 is considered a strong candidate for the 15q13.3 deletion syndrome's pathogenicity. Patient 1 has cognitive impairment, learning disabilities, hyperactivity and subtle dysmorphic features whereas patient 2 has mild language impairment with speech difficulty, mild dysmorphia, heart defect and interestingly a high IQ that has not been reported in 15q13.3 syndrome patients before. Our study presents first report of such two successive deletions in 15q13.3 syndrome patients and a high IQ in a 15q13.3 syndrome patient. Our study expands the breakpoints and phenotypic features related to 15q13.3 syndrome.
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Affiliation(s)
- Maysoon Alsagob
- 1Department of Genetics, King Faisal Specialist Hospital and Research Centre, MBC: 03, Riyadh, 11211 Kingdom of Saudi Arabia
| | - Mustafa A Salih
- 2Division of Pediatric Neurology, Department of Pediatrics, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Muddathir H A Hamad
- 2Division of Pediatric Neurology, Department of Pediatrics, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Yusra Al-Yafee
- 1Department of Genetics, King Faisal Specialist Hospital and Research Centre, MBC: 03, Riyadh, 11211 Kingdom of Saudi Arabia
| | - Jawaher Al-Zahrani
- 1Department of Genetics, King Faisal Specialist Hospital and Research Centre, MBC: 03, Riyadh, 11211 Kingdom of Saudi Arabia
| | - Albandary Al-Bakheet
- 1Department of Genetics, King Faisal Specialist Hospital and Research Centre, MBC: 03, Riyadh, 11211 Kingdom of Saudi Arabia
| | - Michael Nester
- 3Department of Neurosciences, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Nadia Sakati
- 3Department of Neurosciences, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Salma M Wakil
- 1Department of Genetics, King Faisal Specialist Hospital and Research Centre, MBC: 03, Riyadh, 11211 Kingdom of Saudi Arabia
| | - Ali AlOdaib
- 1Department of Genetics, King Faisal Specialist Hospital and Research Centre, MBC: 03, Riyadh, 11211 Kingdom of Saudi Arabia
| | - Dilek Colak
- 4Department of Biostatistics, Epidemiology, and Scientific Computing, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Namik Kaya
- 1Department of Genetics, King Faisal Specialist Hospital and Research Centre, MBC: 03, Riyadh, 11211 Kingdom of Saudi Arabia.,2Division of Pediatric Neurology, Department of Pediatrics, College of Medicine, King Saud University, Riyadh, Saudi Arabia
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11
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Dougherty ML, Underwood JG, Nelson BJ, Tseng E, Munson KM, Penn O, Nowakowski TJ, Pollen AA, Eichler EE. Transcriptional fates of human-specific segmental duplications in brain. Genome Res 2018; 28:1566-1576. [PMID: 30228200 PMCID: PMC6169893 DOI: 10.1101/gr.237610.118] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 08/07/2018] [Indexed: 01/27/2023]
Abstract
Despite the importance of duplicate genes for evolutionary adaptation, accurate gene annotation is often incomplete, incorrect, or lacking in regions of segmental duplication. We developed an approach combining long-read sequencing and hybridization capture to yield full-length transcript information and confidently distinguish between nearly identical genes/paralogs. We used biotinylated probes to enrich for full-length cDNA from duplicated regions, which were then amplified, size-fractionated, and sequenced using single-molecule, long-read sequencing technology, permitting us to distinguish between highly identical genes by virtue of multiple paralogous sequence variants. We examined 19 gene families as expressed in developing and adult human brain, selected for their high sequence identity (average >99%) and overlap with human-specific segmental duplications (SDs). We characterized the transcriptional differences between related paralogs to better understand the birth-death process of duplicate genes and particularly how the process leads to gene innovation. In 48% of the cases, we find that the expressed duplicates have changed substantially from their ancestral models due to novel sites of transcription initiation, splicing, and polyadenylation, as well as fusion transcripts that connect duplication-derived exons with neighboring genes. We detect unannotated open reading frames in genes currently annotated as pseudogenes, while relegating other duplicates to nonfunctional status. Our method significantly improves gene annotation, specifically defining full-length transcripts, isoforms, and open reading frames for new genes in highly identical SDs. The approach will be more broadly applicable to genes in structurally complex regions of other genomes where the duplication process creates novel genes important for adaptive traits.
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Affiliation(s)
- Max L Dougherty
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195, USA
| | - Jason G Underwood
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195, USA.,Pacific Biosciences (PacBio) of California, Incorporated, Menlo Park, California 94025, USA
| | - Bradley J Nelson
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195, USA
| | - Elizabeth Tseng
- Pacific Biosciences (PacBio) of California, Incorporated, Menlo Park, California 94025, USA
| | - Katherine M Munson
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195, USA
| | - Osnat Penn
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195, USA
| | - Tomasz J Nowakowski
- Department of Anatomy, University of California, San Francisco, San Francisco, California 94158, USA.,Department of Psychiatry, University of California, San Francisco, San Francisco, California 94158, USA
| | - Alex A Pollen
- Department of Neurology, University of California, San Francisco, San Francisco, California 94158, USA
| | - Evan E Eichler
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195, USA.,Howard Hughes Medical Institute, University of Washington, Seattle, Washington 98195, USA
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12
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Genetic variation in CHRNA7 and CHRFAM7A is associated with nicotine dependence and response to varenicline treatment. Eur J Hum Genet 2018; 26:1824-1831. [PMID: 30089821 DOI: 10.1038/s41431-018-0223-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 06/15/2018] [Accepted: 07/03/2018] [Indexed: 12/15/2022] Open
Abstract
The role of nicotinic acetylcholine receptors (nAChR) in nicotine dependence (ND) is well established; CHRNA7, encoding the α7 subunit, has a still uncertain role in ND, although it is implicated in a wide range of neuropsychiatric conditions. CHRFAM7A, a hybrid gene containing a partial duplication of CHRNA7, is possibly involved in modulating α7 nAChR function. The aim of this study was to investigate the role of CHRNA7 and CHRFAM7A genetic variants in ND and to test the hypothesis that α7 nAChR variation may modulate the efficacy of varenicline treatment in smoking cessation. We assessed CHRNA7 and CHRFAM7A copy number, CHRFAM7A exon 6 ∆2 bp polymorphism, and sequence variants in the CHRNA7 proximal promoter in an Italian sample of 408 treatment-seeking smokers. We conducted case-control and quantitative association analyses using two smoking measures (cigarettes per day, CPD, and Fagerström Test for Nicotine Dependence, FTND). Next, driven by the hypothesis that varenicline may exert some of its therapeutic effects through activation of α7 nAChRs, we restricted the analysis to a subgroup of 142 smokers who received varenicline treatment. The CHRNA7 promoter variant rs28531779 showed association with both smoking quantitative measures (FNTD p = 0.026, β = 0.89, 95% CI 0.11-1.67; CPD p = 0.006, β = 4.82 95% CI 1.42-8.22). Moreover, in the varenicline-treated subgroup we observed association of CHRFAM7A copy number with 6 months smoking abstinence (p = 0.035, OR = 3.18, 95% CI = 1.09-9.30). Thus, our study points to a possible role of genetic variation in CHRNA7 and CHRFAM7A in tobacco addiction mechanisms and response to varenicline treatment.
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13
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Mechanistic insights into the genetics of affective psychosis from Prader-Willi syndrome. Lancet Psychiatry 2018; 5:370-378. [PMID: 29352661 DOI: 10.1016/s2215-0366(18)30009-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/19/2017] [Accepted: 10/26/2017] [Indexed: 12/14/2022]
Abstract
Schizophrenia and bipolar disorder are common, severe, and disabling psychotic disorders, which are difficult to research. We argue that the genetically determined neurodevelopmental disorder Prader-Willi syndrome (PWS), which is associated with a high risk of affective psychotic illness, can provide a window into genetic mechanisms and associated neural pathways. People with PWS can all show non-psychotic psychopathology and problem behaviours, but the prevalence of psychotic illness differs markedly by genetic subtype; people with PWS due to chromosome 15 maternal uniparental disomy have higher prevalence of psychotic illness compared with patients with PWS due to 15q11-13 deletions of paternal origin. On the basis of this observation and the neural differences between genetic subtypes, we hypothesise that the combined effects of the absent expression of specific maternally imprinted genes at 15q11-13, and excess maternally imprinted or paternally expressed genes on chromosome 15, affect the γ-aminobutyric acid-glutamatergic pathways and associated neural networks that underpin mood regulation and sensory processing, resulting in psychotic illness. We propose a model of potential mechanisms of psychosis in PWS, which might be relevant in the general population, and should inform future research.
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14
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Calabrò M, Mandelli L, Crisafulli C, Sidoti A, Jun TY, Lee SJ, Han C, Patkar AA, Masand PS, Pae CU, Serretti A. Genes Involved in Neurodevelopment, Neuroplasticity, and Bipolar Disorder: CACNA1C, CHRNA1, and MAPK1. Neuropsychobiology 2018; 74:159-168. [PMID: 28494468 DOI: 10.1159/000468543] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 03/05/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND Bipolar disorder (BPD) is a common and severe mental disorder. The involvement of genetic factors in the pathophysiology of BPD is well known. In the present study, we tested the association of several single-nucleotide polymorphisms (SNPs) within 3 strong candidate genes (CACNA1C, CHRNA7, and MAPK1) with BPD. These genes are involved in monoamine-related pathways, as well as in dendrite development, neuronal survival, synaptic plasticity, and memory/learning. METHODS One hundred and thirty-two subjects diagnosed with BPD and 326 healthy controls of Korean ancestry were genotyped for 40 SNPs within CACNA1C, CHRNA17, and MAPK1. Distribution of alleles and block of haplotypes within each gene were compared in cases and controls. Interactions between variants in different loci were also tested. RESULTS Significant differences in the distribution of alleles between the cases and controls were detected for rs1016388 within CACNA1C, rs1514250, rs2337980, rs6494223, rs3826029 and rs4779565 within CHRNA7, and rs8136867 within MAPK1. Haplotype analyses also confirmed an involvement of variations within these genes in BPD. Finally, exploratory epistatic analyses demonstrated potential interactive effects, especially regarding variations in CACNA1C and CHRNA7. LIMITATIONS Limited sample size and risk of false-positive findings. DISCUSSION Our data suggest a possible role of these 3 genes in BPD. Alterations of 1 or more common brain pathways (e.g., neurodevelopment and neuroplasticity, calcium signaling) may explain the obtained results.
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Affiliation(s)
- Marco Calabrò
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy
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15
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Abstract
Chromosome 15q11q13 is among the least stable regions in the genome due to its highly complex genomic architecture. Low copy repeat elements at 15q13.3 facilitate recurrent copy number variants (CNVs), with deletions established as pathogenic and CHRNA7 implicated as a candidate gene. However, the pathogenicity of duplications of CHRNA7 is unclear, as they are found in affected probands as well as in reportedly healthy parents and unaffected control individuals. We evaluated 18 children with microduplications involving CHRNA7, identified by clinical chromosome microarray analysis (CMA). Comprehensive phenotyping revealed high prevalence of developmental delay/intellectual disability, autism spectrum disorder, and attention deficit/hyperactivity disorder. As CHRNA7 duplications are the most common CNVs identified by clinical CMA, this study provides anticipatory guidance for those involved with care of affected individuals.
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16
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Baird A, Coimbra R, Dang X, Eliceiri BP, Costantini TW. Up-regulation of the human-specific CHRFAM7A gene in inflammatory bowel disease. BBA CLINICAL 2016; 5:66-71. [PMID: 27051591 PMCID: PMC4802402 DOI: 10.1016/j.bbacli.2015.12.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 12/16/2015] [Accepted: 12/17/2015] [Indexed: 12/16/2022]
Abstract
Background: The α7-subunit of the α7-nicotinic acetylcholine receptor (α7-nAChR) is an obligatory intermediate for the anti-inflammatory effects of the vagus nerve. But in humans, there exists a second gene called CHRFAM7A that encodes a dominant negative α7-nAChR inhibitor. Here, we investigated whether their expression was altered in inflammatory bowel disease (IBD) and colon cancer. Methods: Quantitative RT-PCR measured gene expression of human α7-nAChR gene (CHRNA7), CHRFAM7A, TBC3D1, and actin in biopsies of normal large and small intestine, and compared to their expression in biopsies of ulcerative colitis, Crohn's disease, and colon cancer. Results: qRT-PCR showed that CHRFAM7A and CHRNA7 gene expression was significantly (p < .02) up-regulated in IBD (N = 64). Gene expression was unchanged in colon cancer. Further analyses revealed that there were differences in ulcerative colitis and Crohn's Disease. Colon biopsies of ulcerative colitis (N = 33) confirmed increased expression of CHRFAM7A and decreased in CHRNA7 expression (p < 0.001). Biopsies of Crohn's disease (N = 31), however, showed only small changes in CHRFAM7A expression (p < 0.04) and no change in CHRNA7. When segregated by tissue source, both CHRFAM7A up-regulation (p < 0.02) and CHRNA7 down-regulation (p < 0.001) were measured in colon, but not in small intestine. Conclusion: The human-specific CHRFAM7A gene is up-regulated, and its target, CHRNA7, down-regulated, in IBD. Differences between ulcerative colitis and Crohn's disease tie to location of disease. Significance: The appearance of IBD in modern humans may be consequent to the emergence of CHRFAM7A, a human-specific α7-nAChR antagonist. CHRFAM7A could present a new, unrecognized target for development of IBD therapeutics. CHRFAM7A is a pro-inflammatory and human-specific gene not found in other species. CHRFAM7A expression is elevated in certain IBD, but its target CHRNA7 decreased. Changes in CHRFAM7A and CHRNA7 expression are disease- and tissue site specific. Some IBDs may be examples of “off-target disease sequelae” of human evolution. Animal modeling of human disease do not test contributions of human-specific genes.
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Affiliation(s)
- Andrew Baird
- Division of Trauma, Surgical Critical Care, Burns and Acute Care Surgery, Department of Surgery, University of California San Diego, La Jolla, CA, USA
| | - Raul Coimbra
- Division of Trauma, Surgical Critical Care, Burns and Acute Care Surgery, Department of Surgery, University of California San Diego, La Jolla, CA, USA
| | - Xitong Dang
- Division of Trauma, Surgical Critical Care, Burns and Acute Care Surgery, Department of Surgery, University of California San Diego, La Jolla, CA, USA; The Key Laboratory of Medical Electrophysiology, Institute of Cardiovascular Research, Sichuan Medical University, Luzhou, China
| | - Brian P Eliceiri
- Division of Trauma, Surgical Critical Care, Burns and Acute Care Surgery, Department of Surgery, University of California San Diego, La Jolla, CA, USA
| | - Todd W Costantini
- Division of Trauma, Surgical Critical Care, Burns and Acute Care Surgery, Department of Surgery, University of California San Diego, La Jolla, CA, USA
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17
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Damiano JA, Mullen SA, Hildebrand MS, Bellows ST, Lawrence KM, Arsov T, Dibbens L, Major H, Dahl HHM, Mefford HC, Darbro BW, Scheffer IE, Berkovic SF. Evaluation of multiple putative risk alleles within the 15q13.3 region for genetic generalized epilepsy. Epilepsy Res 2015; 117:70-3. [DOI: 10.1016/j.eplepsyres.2015.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/28/2015] [Accepted: 09/07/2015] [Indexed: 12/11/2022]
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18
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Sinkus ML, Graw S, Freedman R, Ross RG, Lester HA, Leonard S. The human CHRNA7 and CHRFAM7A genes: A review of the genetics, regulation, and function. Neuropharmacology 2015; 96:274-88. [PMID: 25701707 PMCID: PMC4486515 DOI: 10.1016/j.neuropharm.2015.02.006] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 02/04/2015] [Accepted: 02/06/2015] [Indexed: 01/16/2023]
Abstract
The human α7 neuronal nicotinic acetylcholine receptor gene (CHRNA7) is ubiquitously expressed in both the central nervous system and in the periphery. CHRNA7 is genetically linked to multiple disorders with cognitive deficits, including schizophrenia, bipolar disorder, ADHD, epilepsy, Alzheimer's disease, and Rett syndrome. The regulation of CHRNA7 is complex; more than a dozen mechanisms are known, one of which is a partial duplication of the parent gene. Exons 5-10 of CHRNA7 on chromosome 15 were duplicated and inserted 1.6 Mb upstream of CHRNA7, interrupting an earlier partial duplication of two other genes. The chimeric CHRFAM7A gene product, dupα7, assembles with α7 subunits, resulting in a dominant negative regulation of function. The duplication is human specific, occurring neither in primates nor in rodents. The duplicated α7 sequence in exons 5-10 of CHRFAM7A is almost identical to CHRNA7, and thus is not completely queried in high throughput genetic studies (GWAS). Further, pre-clinical animal models of the α7nAChR utilized in drug development research do not have CHRFAM7A (dupα7) and cannot fully model human drug responses. The wide expression of CHRNA7, its multiple functions and modes of regulation present challenges for study of this gene in disease. This article is part of the Special Issue entitled 'The Nicotinic Acetylcholine Receptor: From Molecular Biology to Cognition'.
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Affiliation(s)
- Melissa L Sinkus
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA.
| | - Sharon Graw
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA.
| | - Robert Freedman
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA; Veterans Affairs Medical Research Center, Denver, CO 80262, USA.
| | - Randal G Ross
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA.
| | - Henry A Lester
- Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA.
| | - Sherry Leonard
- Department of Psychiatry, University of Colorado Denver, Aurora, CO 80045, USA; Veterans Affairs Medical Research Center, Denver, CO 80262, USA.
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19
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Gillentine MA, Schaaf CP. The human clinical phenotypes of altered CHRNA7 copy number. Biochem Pharmacol 2015; 97:352-362. [PMID: 26095975 DOI: 10.1016/j.bcp.2015.06.012] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 06/10/2015] [Indexed: 01/03/2023]
Abstract
Copy number variants (CNVs) have been implicated in multiple neuropsychiatric conditions, including autism spectrum disorder (ASD), schizophrenia, and intellectual disability (ID). Chromosome 15q13 is a hotspot for such CNVs due to the presence of low copy repeat (LCR) elements, which facilitate non-allelic homologous recombination (NAHR). Several of these CNVs have been overrepresented in individuals with neuropsychiatric disorders; yet variable expressivity and incomplete penetrance are commonly seen. Dosage sensitivity of the CHRNA7 gene, which encodes for the α7 nicotinic acetylcholine receptor in the human brain, has been proposed to have a major contribution to the observed cognitive and behavioral phenotypes, as it represents the smallest region of overlap to all the 15q13.3 deletions and duplications. Individuals with zero to four copies of CHRNA7 have been reported in the literature, and represent a range of clinical severity, with deletions causing generally more severe and more highly penetrant phenotypes. Potential mechanisms to account for the variable expressivity within each group of 15q13.3 CNVs will be discussed.
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Affiliation(s)
- Madelyn A Gillentine
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Christian P Schaaf
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States.
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20
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Chatzidaki A, Fouillet A, Li J, Dage J, Millar NS, Sher E, Ursu D. Pharmacological Characterisation of Nicotinic Acetylcholine Receptors Expressed in Human iPSC-Derived Neurons. PLoS One 2015; 10:e0125116. [PMID: 25906356 PMCID: PMC4408108 DOI: 10.1371/journal.pone.0125116] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 03/20/2015] [Indexed: 01/21/2023] Open
Abstract
Neurons derived from human induced pluripotent stem cells (iPSCs) represent a potentially valuable tool for the characterisation of neuronal receptors and ion channels. Previous studies on iPSC-derived neuronal cells have reported the functional characterisation of a variety of receptors and ion channels, including glutamate receptors, γ-aminobutyric acid (GABA) receptors and several voltage-gated ion channels. In the present study we have examined the expression and functional properties of nicotinic acetylcholine receptors (nAChRs) in human iPSC-derived neurons. Gene expression analysis indicated the presence of transcripts encoding several nAChR subunits, with highest levels detected for α3-α7, β1, β2 and β4 subunits (encoded by CHRNA3-CHRNA7, CHRNB1, CHRNB2 and CHRNB4 genes). In addition, similarly high transcript levels were detected for the truncated dupα7 subunit transcript, encoded by the partially duplicated gene CHRFAM7A, which has been associated with psychiatric disorders such as schizophrenia. The functional properties of these nAChRs have been examined by calcium fluorescence and by patch-clamp recordings. The data obtained suggest that the majority of functional nAChRs expressed in these cells have pharmacological properties typical of α7 receptors. Large responses were induced by a selective α7 agonist (compound B), in the presence of the α7-selective positive allosteric modulator (PAM) PNU-120596, which were blocked by the α7-selective antagonist methyllycaconitine (MLA). In addition, a small proportion of the neurons express nAChRs with properties typical of heteromeric (non-α7 containing) nAChR subtypes. These cells therefore represent a great tool to advance our understanding of the properties of native human nAChRs, α7 in particular.
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Affiliation(s)
- Anna Chatzidaki
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, United Kingdom
| | - Antoine Fouillet
- Lilly Research Centre, Eli Lilly and Company, Windlesham, Surrey, United Kingdom
| | - Jingling Li
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, United States of America
| | - Jeffrey Dage
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, United States of America
| | - Neil S. Millar
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, United Kingdom
| | - Emanuele Sher
- Lilly Research Centre, Eli Lilly and Company, Windlesham, Surrey, United Kingdom
| | - Daniel Ursu
- Lilly Research Centre, Eli Lilly and Company, Windlesham, Surrey, United Kingdom
- * E-mail:
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21
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Dang X, Eliceiri BP, Baird A, Costantini TW. CHRFAM7A: a human-specific α7-nicotinic acetylcholine receptor gene shows differential responsiveness of human intestinal epithelial cells to LPS. FASEB J 2015; 29:2292-302. [PMID: 25681457 DOI: 10.1096/fj.14-268037] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 01/20/2015] [Indexed: 02/06/2023]
Abstract
The human genome contains a unique, distinct, and human-specific α7-nicotinic acetylcholine receptor (α7nAChR) gene [CHRNA7 (gene-encoding α7-nicotinic acetylcholine receptor)] called CHRFAM7A (gene-encoding dup-α7-nicotinic acetylcholine receptor) on a locus of chromosome 15 associated with mental illness, including schizophrenia. Located 5' upstream from the "wild-type" CHRNA7 gene that is found in other vertebrates, we demonstrate CHRFAM7A expression in a broad range of epithelial cells and sequenced the CHRFAM7A transcript found in normal human fetal small intestine epithelial (FHs) cells to prove its identity. We then compared its expression to CHRNA7 in 11 gut epithelial cell lines, showed that there is a differential response to LPS when compared to CHRNA7, and characterized the CHRFAM7A promoter. We report that both CHRFAM7A and CHRNA7 gene expression are widely distributed in human epithelial cell lines but that the levels of CHRFAM7A gene expression vary up to 5000-fold between different gut epithelial cells. A 3-hour treatment of epithelial cells with 100 ng/ml LPS increased CHRFAM7A gene expression by almost 1000-fold but had little effect on CHRNA7 gene expression. Mapping the regulatory elements responsible for CHRFAM7A gene expression identifies a 1 kb sequence in the UTR of the CHRFAM7A gene that is modulated by LPS. Taken together, these data establish the presence, identity, and differential regulation of the human-specific CHRFAM7A gene in human gut epithelial cells. In light of the fact that CHRFAM7A expression is reported to modulate ligand binding to, and alter the activity of, the wild-type α7nAChR ligand-gated pentameric ion channel, the findings point to the existence of a species-specific α7nAChR response that might regulate gut epithelial function in a human-specific fashion.
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Affiliation(s)
- Xitong Dang
- *Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California, USA; and Cardiovascular Research Center, Luzhou Medical College, Luzhou, Sichuan, China
| | - Brian P Eliceiri
- *Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California, USA; and Cardiovascular Research Center, Luzhou Medical College, Luzhou, Sichuan, China
| | - Andrew Baird
- *Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California, USA; and Cardiovascular Research Center, Luzhou Medical College, Luzhou, Sichuan, China
| | - Todd W Costantini
- *Division of Trauma, Surgical Critical Care, Burns, and Acute Care Surgery, Department of Surgery, University of California, San Diego Health Sciences, San Diego, California, USA; and Cardiovascular Research Center, Luzhou Medical College, Luzhou, Sichuan, China
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22
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Costantini TW, Dang X, Coimbra R, Eliceiri BP, Baird A. CHRFAM7A, a human-specific and partially duplicated α7-nicotinic acetylcholine receptor gene with the potential to specify a human-specific inflammatory response to injury. J Leukoc Biol 2014; 97:247-57. [PMID: 25473097 DOI: 10.1189/jlb.4ru0814-381r] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Conventional wisdom presumes that the α7nAChR product of CHRNA7 expression mediates the ability of the vagus nerve to regulate the inflammatory response to injury and infection. Yet, 15 years ago, a 2nd structurally distinct and human-specific α7nAChR gene was discovered that has largely escaped attention of the inflammation research community. The gene, originally called dupα7nAChR but now known as CHRFAM7A, has been studied exhaustively in psychiatric research because of its association with mental illness. However, dupα7nAChR/CHRFAM7A expression is relatively low in human brain but elevated in human leukocytes. Furthermore, α7nAChR research in human tissues has been confounded by cross-reacting antibodies and nonspecific oligonucleotide primers that crossreact in immunoblotting, immunohistochemistry, and RT-PCR. Yet, 3 independent reports show the human-specific CHRFAM7A changes cell responsiveness to the canonical α7nAChR/CHRNA7 ion-gated channel. Because of its potential for the injury research community, its possible significance to human leukocyte biology, and its relevance to human inflammation, we review the discovery and structure of the dupα7nAChR/CHRFAM7A gene, the distribution of its mRNA, and its biologic activities and then discuss its possible role(s) in specifying human inflammation and injury. In light of emerging concepts that point to a role for human-specific genes in complex human disease, the existence of a human-specific α7nAChR regulating inflammatory responses in injury underscores the need for caution in extrapolating findings in the α7nAChR literature to man. To this end, we discuss the translational implications of a uniquely human α7nAChR-like gene on new drug target discovery and therapeutics development for injury, infection, and inflammation.
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Affiliation(s)
- Todd W Costantini
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
| | - Xitong Dang
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
| | - Raul Coimbra
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
| | - Brian P Eliceiri
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
| | - Andrew Baird
- Division of Trauma, Surgical Critical Care, Burn and Acute Critical Care, Department of Surgery, University of California San Diego Health Sciences, San Diego, California, USA
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23
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Wang Y, Xiao C, Indersmitten T, Freedman R, Leonard S, Lester HA. The duplicated α7 subunits assemble and form functional nicotinic receptors with the full-length α7. J Biol Chem 2014; 289:26451-26463. [PMID: 25056953 DOI: 10.1074/jbc.m114.582858] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The α7 nicotinic acetylcholine receptor gene (CHRNA7) is linked to schizophrenia. A partial duplication of CHRNA7 (CHRFAM7A) is found in humans on 15q13-14. Exon 6 of CHRFAM7A harbors a 2-bp deletion polymorphism, CHRFAM7AΔ2bp, which is also associated with schizophrenia. To understand the effects of the duplicated subunits on α7 receptors, we fused α7, dupα7, and dupΔα7 subunits with various fluorescent proteins. The duplicated subunits co-localized with full-length α7 subunits in mouse neuroblastoma cells (Neuro2a) as well as rat hippocampal neurons. We investigated the interaction between the duplicated subunits and full-length α7 by measuring Förster resonance energy transfer using donor recovery after photobleaching and fluorescence lifetime imaging microscopy. The results revealed that the duplicated proteins co-assemble with α7. In electrophysiological studies, Leu at the 9'-position in the M2 membrane-spanning segment was replaced with Cys in dupα7 or dupΔα7, and constructs were co-transfected with full-length α7 in Neuro2a cells. Exposure to ethylammonium methanethiosulfonate inhibited acetylcholine-induced currents, showing that the assembled functional nicotinic acetylcholine receptors (nAChRs) included the duplicated subunit. Incorporation of dupα7 and dupΔα7 subunits modestly changes the sensitivity of receptors to choline and varenicline. Thus, the duplicated proteins are assembled and transported to the cell membrane together with full-length α7 subunits and alter the function of the nAChRs. The characterization of dupα7 and dupΔα7 as well as their influence on α7 nAChRs may help explain the pathophysiology of schizophrenia and may suggest therapeutic strategies.
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Affiliation(s)
- Ying Wang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125 and
| | - Cheng Xiao
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125 and
| | - Tim Indersmitten
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125 and
| | - Robert Freedman
- Department of Psychiatry, University of Colorado at Denver, Denver, Colorado 80045
| | - Sherry Leonard
- Department of Psychiatry, University of Colorado at Denver, Denver, Colorado 80045
| | - Henry A Lester
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125 and.
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24
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Ronai Z, Kovacs-Nagy R, Szantai E, Elek Z, Sasvari-Szekely M, Faludi G, Benkovits J, Rethelyi JM, Szekely A. Glycogen synthase kinase 3 beta gene structural variants as possible risk factors of bipolar depression. Am J Med Genet B Neuropsychiatr Genet 2014; 165B:217-22. [PMID: 24677591 PMCID: PMC3980030 DOI: 10.1002/ajmg.b.32223] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 01/10/2014] [Indexed: 11/07/2022]
Abstract
The glycogen synthase kinase 3B (GSK3B) is an important target protein of several antidepressants, such as lithium, a mood stabilizer. Recent studies associated structural variations of the GSK3B gene to bipolar disorder (BP), although replications were not conclusive. Here we present data on copy number variations (CNVs) of the GSK3B gene probing the 9th exon region in 846 individuals (414 controls, 172 patients with major depressive disorder (MDD) and 260 with BP). A significant accumulation (odds ratio: 5.5, P = 0.00051) of the amplified exon 9 region was found in patients (22 out of 432) compared to controls (4 of 414). Analyzing patient subgroups, GSK3B structural variants were found to be risk factors of BP particularly (P = 0.00001) with an odds ratio of 8.1 while no such effect was shown in the MDD group. The highest odds (19.7 ratio) for bipolar disorder was observed in females with the amplified exon 9 region. A more detailed analysis of the identified GSK3B CNV by a set of probes covering the GSK3B gene and the adjacent NR1I2 and C3orf15 genes showed that the amplified sequences contained 3' (downstream) segments of the GSK3B and NR1I2 genes but none of them involved the C3orf15 gene. Therefore, the copy number variation of the GSK3B gene could be described as a complex set of structural variants involving partial duplications and deletions, simultaneously. In summary, here we confirmed significant association of the GSK3B CNV and bipolar disorder pointing out that the copy number and extension of the CNV varies among individuals.
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Affiliation(s)
- Zsolt Ronai
- Institute of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Reka Kovacs-Nagy
- Institute of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Eszter Szantai
- Institute of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Zsuzsanna Elek
- Institute of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Maria Sasvari-Szekely
- Institute of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Gabor Faludi
- Department of Clinical and Theoretical Mental Health, Kutvolgyi Clinical Center, Semmelweis University, Budapest, Hungary
| | - Judit Benkovits
- Department of Psychiatry and Psychotherapy, Semmelweis University, Budapest, Hungary
| | - Janos M. Rethelyi
- Department of Psychiatry and Psychotherapy, Semmelweis University, Budapest, Hungary
| | - Anna Szekely
- Institute of Psychology, Eotvos Lorand University, Budapest, Hungary,Corresponding author Anna Szekely (associate professor) Institute of Psychology, Eotvos Lorand University, Budapest, Hungary Address: Izabella u. 46, Budapest, Hungary-1064 Tel: (+3620) 466-4554 Fax: (+361) 461-2691
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25
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Masurel-Paulet A, Drumare I, Holder M, Cuisset JM, Vallée L, Defoort S, Bourgois B, Pernes P, Cuvellier JC, Huet F, Chehadeh SE, Thevenon J, Callier P, Thauvin C, Faivre L, Andrieux J. Further delineation of eye manifestations in homozygous 15q13.3 microdeletions including TRPM1: a differential diagnosis of ceroid lipofuscinosis. Am J Med Genet A 2014; 164A:1537-44. [PMID: 24668847 DOI: 10.1002/ajmg.a.36471] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 12/31/2013] [Indexed: 11/11/2022]
Abstract
The 15q13.3 heterozygous microdeletion is a fairly common microdeletion syndrome with marked clinical variability and incomplete penetrance. The average size of the deletion, which comprises six genes including CHRNA7, is 1.5 Mb. CHRNA7 has been identified as the gene responsible for the neurological phenotype in this microdeletion syndrome. Only seven patients with a homozygous microdeletion that includes at least CHRNA7, and is inherited from both parents have been described in the literature. The aim of this study was to further describe the distinctive eye manifestations from the analysis in the three French patients diagnosed with the classical 1.5 Mb homozygous microdeletion. Patients' ages ranged from 30 months to 9 years, and included one sib pair. They all displayed a remarkably severe identifiable clinical phenotype that included congenital blindness and convulsive encephalopathy with inconstant abnormal movements. The ophthalmological examination revealed a lack of eye tracking, optic nerve pallor, an immature response with increased latencies with no response to the checkerboard stimulations at the visual evoked potential examination, and a distinctive retina dystrophy with a negative electroretinogram in which the "b" wave was smaller than the "a" wave after a dark adapted pupil and bright flash in all patients. Clear genotype-phenotype correlations emerged, showing that this eye phenotype was secondary to homozygous deletion of TRPM1, the gene responsible for autosomal recessive congenital stationary night blindness. The main differential diagnosis is ceroid lipofuscinosis.
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Affiliation(s)
- Alice Masurel-Paulet
- Centre de Génétique et Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Hôpital d'Enfants, CHU Dijon, France
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26
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Beggiato S, Tanganelli S, Fuxe K, Antonelli T, Schwarcz R, Ferraro L. Endogenous kynurenic acid regulates extracellular GABA levels in the rat prefrontal cortex. Neuropharmacology 2014; 82:11-8. [PMID: 24607890 DOI: 10.1016/j.neuropharm.2014.02.019] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 02/07/2014] [Accepted: 02/25/2014] [Indexed: 12/17/2022]
Abstract
The tryptophan metabolite kynurenic acid (KYNA) is an endogenous antagonist of the α7 nicotinic acetylcholine receptor (α7nAChR) and, at higher concentrations, inhibits ionotropic glutamate receptors. Increases in KYNA levels are seen in brain and cerebrospinal fluid in individuals with schizophrenia (SZ) and may be causally related to cognitive deficits in SZ and other psychiatric diseases. As dysfunction of circuits involving GABAergic neurons in the prefrontal cortex (PFC) likely plays a role in the cognitive impairments seen in these disorders, we examined the effects of KYNA on extracellular GABA in this brain area. Applied to awake rats for 2 h by reverse dialysis, KYNA concentration-dependently and reversibly reduced extracellular GABA levels, with 300 nM KYNA causing a nadir of ∼45% of baseline concentrations. This effect was not duplicated by reverse dialysis of the selective glycineB receptor antagonist 7-Cl-KYNA (100 nM) or the AMPA/kainate receptor antagonist CNQX (100 μM), and was prevented by co-application of galantamine (5 μM), a positive allosteric modulator of the α7nAChR. Conversely, inhibition of endogenous KYNA formation by reverse dialysis of (S)-4-(ethylsulfonyl)benzoylalanine (ESBA; 5 mM) reversibly increased GABA levels in the PFC, reaching a peak of ∼160% of baseline concentrations. Co-infusion of 30 nM KYNA neutralized this effect. Taken together, these results demonstrate a role for endogenous KYNA in the bi-directional control of GABAergic neurotransmission in the PFC. Pharmacological manipulation of KYNA may therefore be useful in the treatment of GABAergic impairments in SZ and other brain disorders involving the PFC.
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Affiliation(s)
- Sarah Beggiato
- Department of Medical Sciences, University of Ferrara, Italy; Laboratory for the Technology of Advanced Therapies (LTTA Centre), University of Ferrara, Italy.
| | - Sergio Tanganelli
- Department of Medical Sciences, University of Ferrara, Italy; Laboratory for the Technology of Advanced Therapies (LTTA Centre), University of Ferrara, Italy
| | - Kjell Fuxe
- Department of Neuroscience, Karolinska Institute, Stockholm, Sweden
| | - Tiziana Antonelli
- Department of Medical Sciences, University of Ferrara, Italy; Laboratory for the Technology of Advanced Therapies (LTTA Centre), University of Ferrara, Italy
| | - Robert Schwarcz
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Luca Ferraro
- Laboratory for the Technology of Advanced Therapies (LTTA Centre), University of Ferrara, Italy; Department of Life Sciences and Biotechnology, University of Ferrara, Italy
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27
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Szigeti K, Kellermayer B, Lentini JM, Trummer B, Lal D, Doody RS, Yan L, Liu S, Ma C. Ordered subset analysis of copy number variation association with age at onset of Alzheimer's disease. J Alzheimers Dis 2014; 41:1063-71. [PMID: 24787912 PMCID: PMC4866488 DOI: 10.3233/jad-132693] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Genetic heterogeneity is a common problem for genome-wide association studies of complex human diseases. Ordered-subset analysis (OSA) reduces genetic heterogeneity and optimizes the use of phenotypic information, thus improving power under some disease models. We hypothesized that in a genetically heterogeneous disorder such as Alzheimer's disease (AD), utilizing OSA by age at onset (AAO) of AD may increase the power to detect relevant loci. Using this approach, 8 loci were detected, including the chr15 : 30,44 region harboring CHRFAM7A. The association was replicated in the NIA-LOAD Familial Study dataset. CHRFAM7A is a dominant negative regulator of CHRNA7 function, the receptor that facilitates amyloid-β1-42 internalization through endocytosis and has been implicated in AD. OSA, using AAO as a quantitative trait, optimized power and detected replicable signals suggesting that AD is genetically heterogeneous between AAO subsets.
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Affiliation(s)
- Kinga Szigeti
- Department of Neurology, University at Buffalo, SUNY, Buffalo, NY, USA,Correspondence to: Kinga Szigeti, MD, PhD, University of Buffalo SUNY, 100 High Street, Buffalo, NY 14203, USA. Tel.: +1 716 859 3484; Fax: +1 716 859 7833;
| | | | - Jenna M. Lentini
- Department of Neurology, University at Buffalo, SUNY, Buffalo, NY, USA
| | - Brian Trummer
- Department of Neurology, University at Buffalo, SUNY, Buffalo, NY, USA
| | - Deepika Lal
- Department of Neurology, University at Buffalo, SUNY, Buffalo, NY, USA
| | - Rachelle S. Doody
- Alzheimer’s Disease and Memory Disorders Center, Department of Neurology, Baylor College of Medicine, Houston, TX, USA
| | - Li Yan
- Department of Bioinformatics, University at Buffalo, SUNY, Buffalo, NY, USA
| | - Song Liu
- Roswell Park Cancer Institute, Buffalo, NY, USA
| | - Changxing Ma
- Department of Bioinformatics, University at Buffalo, SUNY, Buffalo, NY, USA
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28
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Melchior L, Bertelsen B, Debes NM, Groth C, Skov L, Mikkelsen JD, Brøndum-Nielsen K, Tümer Z. Microduplication of 15q13.3 and Xq21.31 in a family with Tourette syndrome and comorbidities. Am J Med Genet B Neuropsychiatr Genet 2013; 162B:825-31. [PMID: 23894120 DOI: 10.1002/ajmg.b.32186] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 06/26/2013] [Indexed: 12/31/2022]
Abstract
Tourette syndrome (TS) is a childhood onset neurodevelopmental disorder. Although it is widely accepted that genetic factors play a significant role in TS pathogenesis the etiology of this disorder is largely unknown. Identification of rare copy number variations (CNVs) as susceptibility factors in several neuropsychiatric disorders such as attention deficit-hyperactivity disorder (ADHD), autism and schizophrenia, suggests involvement of these rare structural changes also in TS etiology. In a male patient with TS, ADHD, and OCD (obsessive compulsive disorder) we identified two microduplications (at 15q13.3 and Xq21.31) inherited from a mother with subclinical ADHD. The 15q duplication included the CHRNA7 gene; while two genes, PABPC5 and PCDH11X, were within the Xq duplication. The Xq21.31 duplication was present in three brothers with TS including the proband, but not in an unaffected brother, whereas the 15q duplication was present only in the proband and his mother. The structural variations observed in this family may contribute to the observed symptoms, but further studies are necessary to investigate the possible involvement of the described variations in the TS etiology.
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Affiliation(s)
- Linea Melchior
- Applied Human Molecular Genetics, Kennedy Center, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
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29
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Rozycka A, Dorszewska J, Steinborn B, Lianeri M, Winczewska-Wiktor A, Sniezawska A, Wisniewska K, Jagodzinski PP. Association study of the 2-bp deletion polymorphism in exon 6 of the CHRFAM7A gene with idiopathic generalized epilepsy. DNA Cell Biol 2013; 32:640-7. [PMID: 24024466 DOI: 10.1089/dna.2012.1880] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
There is evidence of linkage between the 15q13-q14 locus, containing the gene encoding the α7 subunit (CHRNA7) of the neuronal nicotinic acetylcholine receptor (nAChR) and its partially duplicated isoform (CHRFAM7A), and epilepsy. Additionally, a 2-bp deletion polymorphism (c.497-498delTG; rs67158670) in CHRFAM7A, resulting in a frame shift and truncation of the protein product, is associated with some neurological diseases. This study was designed to explore the possibility of an association of the c.497-498delTG polymorphism of CHRFAM7A with idiopathic generalized epilepsies (IGEs) in Polish children and young patients. The study included 197 IGE patients and 258 unrelated healthy individuals. The frequency of the CHRFAM7A c.497-498delTG polymorphism was determined in each group using heteroduplex analysis. An association between the c.497-498delTG polymorphism of CHRFAM7A and IGE was evidenced. It was demonstrated that the frequency of the CHRFAM7A 2-bp deletion carriers was significantly lower in the IGE patients than in the control group. The observed frequency of 2-bp deletion carriers was high in IGE subjects (64%), but significantly higher in control subjects (76%). Carriers of at least one copy of the -2 bp allele had halved their risk of IGE susceptibility (delTG/delTG and delTG/wild-type versus wild-type/wild-type: odds ratio=0.55; 95% confidence intervals=0.365-0.827; p=0.004). Moreover, it has been demonstrated that this polymorphic variant is associated with the c.524-12_524-11insGTT variation (rs10649395) in intron 7 of CHRFAM7A. Our study substantiates the involvement of the α7 subunit of nAChR in the pathophysiology of IGEs and indicates that the CHRFAM7A c.497-498TG deletion or a nearby polymorphism may play a role in the pathogenesis of IGE. Further work should concentrate on ascertaining the exact mechanism of this polymorphism's effect and its relationship with IGE.
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Affiliation(s)
- Agata Rozycka
- 1 Department of Biochemistry and Molecular Biology, Poznan University of Medical Sciences , Poznan, Poland
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30
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Cabranes JA, Ancín I, Santos JL, Sánchez-Morla E, García-Jiménez MÁ, López-Ibor JJ, Barabash A. No effect of polymorphisms in the non-duplicated region of the CHRNA7 gene on sensory gating P50 ratios in patients with schizophrenia and bipolar disorder. Psychiatry Res 2013; 205:276-8. [PMID: 22981153 DOI: 10.1016/j.psychres.2012.08.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 08/09/2012] [Accepted: 08/16/2012] [Indexed: 11/25/2022]
Abstract
Previous research has reported that bipolar disorder and schizophrenic patients evidence sensory gating deficits. The use of intermediate phenotypes may facilitate genetic studies. Four single nucleotide polymorphisms (SNPs) located on the non-duplicated region of the alpha-7 nicotinic receptor gene (CHRNA7) were genotyped in 95 healthy subjects, 127 bipolar disorder and 153 schizophrenic patients. We evaluated the association of these polymorphisms with P50 evoked potential measures. Our results do not support a role for the candidate gene in this neurophysiological disturbance.
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Affiliation(s)
- José Antonio Cabranes
- Institute of Psychiatry and Mental Health, Hospital Clínico San Carlos, Martín Lagos, S/N 28040, Madrid, Spain
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31
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Perron H, Hamdani N, Faucard R, Lajnef M, Jamain S, Daban-Huard C, Sarrazin S, LeGuen E, Houenou J, Delavest M, Moins-Teiserenc H, Bengoufa D, Yolken R, Madeira A, Garcia-Montojo M, Gehin N, Burgelin I, Ollagnier G, Bernard C, Dumaine A, Henrion A, Gombert A, Le Dudal K, Charron D, Krishnamoorthy R, Tamouza R, Leboyer M, Leboyer M. Molecular characteristics of Human Endogenous Retrovirus type-W in schizophrenia and bipolar disorder. Transl Psychiatry 2012; 2:e201. [PMID: 23212585 PMCID: PMC3565190 DOI: 10.1038/tp.2012.125] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Epidemiological and genome-wide association studies of severe psychiatric disorders such as schizophrenia (SZ) and bipolar disorder (BD), suggest complex interactions between multiple genetic elements and environmental factors. The involvement of genetic elements such as Human Endogenous Retroviruses type 'W' family (HERV-W) has consistently been associated with SZ. HERV-W envelope gene (env) is activated by environmental factors and encodes a protein displaying inflammation and neurotoxicity. The present study addressed the molecular characteristics of HERV-W env in SZ and BD. Hundred and thirty-six patients, 91 with BD, 45 with SZ and 73 healthy controls (HC) were included. HERV-W env transcription was found to be elevated in BD (P<10-4) and in SZ (P=0.012) as compared with HC, but with higher values in BD than in SZ group (P<0.01). The corresponding DNA copy number was paradoxically lower in the genome of patients with BD (P=0.0016) or SZ (P<0.0003) than in HC. Differences in nucleotide sequence of HERV-W env were found between patients with SZ and BD as compared with HC, as well as between SZ and BD. The molecular characteristics of HERV-W env also differ from what was observed in Multiple Sclerosis (MS) and may represent distinct features of the genome of patients with BD and SZ. The seroprevalence for Toxoplasma gondii yielded low but significant association with HERV-W transcriptional level in a subgroup of BD and SZ, suggesting a potential role in particular patients. A global hypothesis of mechanisms inducing such major psychoses is discussed, placing HERV-W at the crossroads between environmental, genetic and immunological factors. Thus, particular infections would act as activators of HERV-W elements in earliest life, resulting in the production of an HERV-W envelope protein, which then stimulates pro-inflammatory and neurotoxic cascades. This hypothesis needs to be further explored as it may yield major changes in our understanding and treatment of severe psychotic disorders.
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Affiliation(s)
- H Perron
- Geneuro, Plan-Les-Ouates, Geneva, Switzerland.
| | - N Hamdani
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France,Université Paris Est Créteil, Faculté de Médecine, Créteil, France
| | - R Faucard
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | - M Lajnef
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France
| | - S Jamain
- Inserm U955, Psychiatrie Génétique, Créteil, France,Fondation Fondamental, Créteil, France
| | - C Daban-Huard
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France
| | - S Sarrazin
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France,CEA Saclay, Neurospin, Gif-Sur-Yvette, France
| | - E LeGuen
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France
| | - J Houenou
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France,CEA Saclay, Neurospin, Gif-Sur-Yvette, France
| | - M Delavest
- Fondation Fondamental, Créteil, France,AP-HP, Université Paris Diderot, Service de Psychiatrie, Hôpital Lariboisiere Fernand Widal, Paris, France
| | - H Moins-Teiserenc
- Jean Dausset Department and INSERM UMRS 940, Hôpital Saint Louis, Paris, France
| | - D Bengoufa
- Jean Dausset Department and INSERM UMRS 940, Hôpital Saint Louis, Paris, France
| | - R Yolken
- Stanley Laboratory of Developmental Neurovirology, Johns Hopkins University Medical Center, Baltimore, MD, USA
| | - A Madeira
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | | | - N Gehin
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | - I Burgelin
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | - G Ollagnier
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | - C Bernard
- Geneuro, Plan-Les-Ouates, Geneva, Switzerland
| | - A Dumaine
- Inserm U955, Psychiatrie Génétique, Créteil, France,Fondation Fondamental, Créteil, France
| | - A Henrion
- Inserm U955, Psychiatrie Génétique, Créteil, France,Fondation Fondamental, Créteil, France
| | - A Gombert
- Inserm U955, Psychiatrie Génétique, Créteil, France,Fondation Fondamental, Créteil, France
| | - K Le Dudal
- Plateforme de Ressources Biologiques AP-HP, Créteil, France,Stanley Research Program, Sheppard Pratt, Baltimore, MD, USA,INSERM-CIC 006, Créteil, France
| | - D Charron
- Jean Dausset Department and INSERM UMRS 940, Hôpital Saint Louis, Paris, France
| | | | - R Tamouza
- Jean Dausset Department and INSERM UMRS 940, Hôpital Saint Louis, Paris, France
| | - M Leboyer
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France,Université Paris Est Créteil, Faculté de Médecine, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, 40, rue de Mesly, 94010 Créteil, France. E-mail:
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Olofsson PS, Rosas-Ballina M, Levine YA, Tracey KJ. Rethinking inflammation: neural circuits in the regulation of immunity. Immunol Rev 2012; 248:188-204. [PMID: 22725962 DOI: 10.1111/j.1600-065x.2012.01138.x] [Citation(s) in RCA: 283] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Neural reflex circuits regulate cytokine release to prevent potentially damaging inflammation and maintain homeostasis. In the inflammatory reflex, sensory input elicited by infection or injury travels through the afferent vagus nerve to integrative regions in the brainstem, and efferent nerves carry outbound signals that terminate in the spleen and other tissues. Neurotransmitters from peripheral autonomic nerves subsequently promote acetylcholine-release from a subset of CD4(+) T cells that relay the neural signal to other immune cells, e.g. through activation of α7 nicotinic acetylcholine receptors on macrophages. Here, we review recent progress in the understanding of the inflammatory reflex and discuss potential therapeutic implications of current findings in this evolving field.
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Affiliation(s)
- Peder S Olofsson
- Laboratory of Biomedical Science, The Feinstein Institute for Medical Research, Manhasset, New York 11030, USA
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Association between the 2-bp deletion polymorphism in the duplicated version of the alpha7 nicotinic receptor gene and P50 sensory gating. Eur J Hum Genet 2012; 21:76-81. [PMID: 22588665 DOI: 10.1038/ejhg.2012.81] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
There is considerable evidence implicating the 15q13.3 region in neuropsychiatric disorders, with the α7 nicotinic receptor gene CHRNA7 the most plausible candidate. This region has multiple duplications and many copy number variants (CNVs). A common CNV involves a partial duplication of CHRNA7 (CHRFAM7A), which occurs in either orientation. We examined the distribution of these alternative genomic arrangements in a large cohort of psychiatric patients, their relatives and controls using the 2-bp deletion polymorphism as a marker for the orientation of CHRFAM7A. We investigated three common alleles for association with psychosis and with the P50 sensory gating deficit, which is strongly associated with psychosis and strongly linked to 15q13.3. We found significant within-family association with P50 (empirical P=0.004), which is robust to population stratification. Most of the effect came from the 2-bp deletion allele, which tags the variant of CHRFAM7A in the same orientation as CHRNA7. This allele is associated with the presence of the P50 sensory gating deficit (empirical P=0.0006). Tests comparing within-family and between-family components of association suggest considerable population stratification in the sample. We found no evidence for association with psychosis, but this may reflect lower power using this phenotype. Four out of six previous association studies found association of different psychiatric phenotypes with the same 2-bp deletion allele.
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34
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Casey JP, Magalhaes T, Conroy JM, Regan R, Shah N, Anney R, Shields DC, Abrahams BS, Almeida J, Bacchelli E, Bailey AJ, Baird G, Battaglia A, Berney T, Bolshakova N, Bolton PF, Bourgeron T, Brennan S, Cali P, Correia C, Corsello C, Coutanche M, Dawson G, de Jonge M, Delorme R, Duketis E, Duque F, Estes A, Farrar P, Fernandez BA, Folstein SE, Foley S, Fombonne E, Freitag CM, Gilbert J, Gillberg C, Glessner JT, Green J, Guter SJ, Hakonarson H, Holt R, Hughes G, Hus V, Igliozzi R, Kim C, Klauck SM, Kolevzon A, Lamb JA, Leboyer M, Le Couteur A, Leventhal BL, Lord C, Lund SC, Maestrini E, Mantoulan C, Marshall CR, McConachie H, McDougle CJ, McGrath J, McMahon WM, Merikangas A, Miller J, Minopoli F, Mirza GK, Munson J, Nelson SF, Nygren G, Oliveira G, Pagnamenta AT, Papanikolaou K, Parr JR, Parrini B, Pickles A, Pinto D, Piven J, Posey DJ, Poustka A, Poustka F, Ragoussis J, Roge B, Rutter ML, Sequeira AF, Soorya L, Sousa I, Sykes N, Stoppioni V, Tancredi R, Tauber M, Thompson AP, Thomson S, Tsiantis J, Van Engeland H, Vincent JB, Volkmar F, Vorstman JAS, Wallace S, Wang K, Wassink TH, White K, Wing K, Wittemeyer K, Yaspan BL, Zwaigenbaum L, Betancur C, Buxbaum JD, Cantor RM, Cook EH, Coon H, Cuccaro ML, Geschwind DH, Haines JL, Hallmayer J, Monaco AP, Nurnberger JI, Pericak-Vance MA, Schellenberg GD, Scherer SW, Sutcliffe JS, Szatmari P, Vieland VJ, Wijsman EM, Green A, Gill M, Gallagher L, Vicente A, Ennis S. A novel approach of homozygous haplotype sharing identifies candidate genes in autism spectrum disorder. Hum Genet 2012; 131:565-79. [PMID: 21996756 PMCID: PMC3303079 DOI: 10.1007/s00439-011-1094-6] [Citation(s) in RCA: 148] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Accepted: 09/15/2011] [Indexed: 01/18/2023]
Abstract
Autism spectrum disorder (ASD) is a highly heritable disorder of complex and heterogeneous aetiology. It is primarily characterized by altered cognitive ability including impaired language and communication skills and fundamental deficits in social reciprocity. Despite some notable successes in neuropsychiatric genetics, overall, the high heritability of ASD (~90%) remains poorly explained by common genetic risk variants. However, recent studies suggest that rare genomic variation, in particular copy number variation, may account for a significant proportion of the genetic basis of ASD. We present a large scale analysis to identify candidate genes which may contain low-frequency recessive variation contributing to ASD while taking into account the potential contribution of population differences to the genetic heterogeneity of ASD. Our strategy, homozygous haplotype (HH) mapping, aims to detect homozygous segments of identical haplotype structure that are shared at a higher frequency amongst ASD patients compared to parental controls. The analysis was performed on 1,402 Autism Genome Project trios genotyped for 1 million single nucleotide polymorphisms (SNPs). We identified 25 known and 1,218 novel ASD candidate genes in the discovery analysis including CADM2, ABHD14A, CHRFAM7A, GRIK2, GRM3, EPHA3, FGF10, KCND2, PDZK1, IMMP2L and FOXP2. Furthermore, 10 of the previously reported ASD genes and 300 of the novel candidates identified in the discovery analysis were replicated in an independent sample of 1,182 trios. Our results demonstrate that regions of HH are significantly enriched for previously reported ASD candidate genes and the observed association is independent of gene size (odds ratio 2.10). Our findings highlight the applicability of HH mapping in complex disorders such as ASD and offer an alternative approach to the analysis of genome-wide association data.
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Affiliation(s)
- Jillian P. Casey
- School of Medicine and Medical Science University College, Dublin 4, Ireland
| | - Tiago Magalhaes
- Instituto Nacional de Saude Dr Ricardo Jorge, Av Padre Cruz 1649-016, Lisbon, Portugal
- BioFIG, Center for Biodiversity, Functional and Integrative Genomics, Campus da FCUL, C2.2.12, Campo Grande, 1749-016 Lisbon, Portugal
- Instituto Gulbenkian de Cîencia, Rua Quinta Grande, 2780-156 Oeiras, Portugal
| | - Judith M. Conroy
- School of Medicine and Medical Science University College, Dublin 4, Ireland
| | - Regina Regan
- School of Medicine and Medical Science University College, Dublin 4, Ireland
| | - Naisha Shah
- School of Medicine and Medical Science University College, Dublin 4, Ireland
| | - Richard Anney
- Autism Genetics Group, Department of Psychiatry, School of Medicine, Trinity College, Dublin 8, Ireland
| | - Denis C. Shields
- School of Medicine and Medical Science University College, Dublin 4, Ireland
| | - Brett S. Abrahams
- Department of Neurology, Center for Autism Research and Treatment, Program in Neurogenetics, Semel Institute, David Geffen School of Medicine at UCLA, Los Angeles, USA
| | - Joana Almeida
- Hospital Pediátrico de Coimbra, 3000–076 Coimbra, Portugal
| | - Elena Bacchelli
- Department of Biology, University of Bologna, 40126 Bologna, Italy
| | - Anthony J. Bailey
- Department of Psychiatry, University of British Columbia, Vancouver, V6T 2A1 Canada
| | | | - Agatino Battaglia
- Stella Maris Institute for Child and Adolescent Neuropsychiatry, 56128 Calambrone, Pisa, Italy
| | - Tom Berney
- Institute of Neuroscience, Newcastle University, Newcastle Upon Tyne, NE1 7RU UK
- Institute of Health and Society, Newcastle University, Newcastle Upon Tyne, NE1 7RU UK
| | - Nadia Bolshakova
- Autism Genetics Group, Department of Psychiatry, School of Medicine, Trinity College, Dublin 8, Ireland
| | - Patrick F. Bolton
- Department of Child and Adolescent Psychiatry, Institute of Psychiatry, London, SE5 8AF UK
| | - Thomas Bourgeron
- Department of Human Genetics and Cognitive Functions, Institut Pasteur, University Paris Diderot-Paris 7, CNRS URA 2182, Fondation FondaMental, 75015 Paris, France
| | - Sean Brennan
- Autism Genetics Group, Department of Psychiatry, School of Medicine, Trinity College, Dublin 8, Ireland
| | - Phil Cali
- Department of Psychiatry, Institute for Juvenile Research, University of Illinois at Chicago, Chicago, IL 60612 USA
| | - Catarina Correia
- Instituto Nacional de Saude Dr Ricardo Jorge, Av Padre Cruz 1649-016, Lisbon, Portugal
- BioFIG, Center for Biodiversity, Functional and Integrative Genomics, Campus da FCUL, C2.2.12, Campo Grande, 1749-016 Lisbon, Portugal
- Instituto Gulbenkian de Cîencia, Rua Quinta Grande, 2780-156 Oeiras, Portugal
| | - Christina Corsello
- Autism and Communicative Disorders Centre, University of Michigan, Ann Arbor, MI 48109-2054 USA
| | - Marc Coutanche
- Department of Psychiatry, University of Oxford, Warneford Hospital, Headington, Oxford, OX3 7JX UK
| | - Geraldine Dawson
- Autism Speaks, New York, 10016 USA
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC 27599-3366 USA
| | - Maretha de Jonge
- Department of Child and Adolescent Psychiatry, University Medical Center, 3508 Utrecht, GA The Netherlands
| | - Richard Delorme
- INSERM U 955, Fondation FondaMental, APHP, Hôpital Robert Debré, Child and Adolescent Psychiatry, 75019 Paris, France
| | - Eftichia Duketis
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, J.W. Goethe University Frankfurt, 60528 Frankfurt, Germany
| | | | - Annette Estes
- Department of Speech and Hearing Sciences, University of Washington, Seattle, WA 98195 USA
| | - Penny Farrar
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Bridget A. Fernandez
- Disciplines of Genetics and Medicine, Memorial University of Newfoundland, St John’s Newfoundland, A1B 3V6 Canada
| | - Susan E. Folstein
- Department of Psychiatry, University of Miami School of Medicine, Miami, FL 33136 USA
| | - Suzanne Foley
- Department of Psychiatry, University of Oxford, Warneford Hospital, Headington, Oxford, OX3 7JX UK
| | - Eric Fombonne
- Division of Psychiatry, McGill University, Montreal, QC H3A 1A1 Canada
| | - Christine M. Freitag
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, J.W. Goethe University Frankfurt, 60528 Frankfurt, Germany
| | - John Gilbert
- The John P. Hussman Institute for Human Genomics, University of Miami School of Medicine, Miami, FL 33136 USA
| | - Christopher Gillberg
- Gillberg Neuropsychiatry Centre, Sahlgrenska Academy, University of Gothenburg, S41345 Gothenburg, Sweden
| | - Joseph T. Glessner
- The Center for Applied Genomics, Division of Human Genetics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
| | - Jonathan Green
- Academic Department of Child Psychiatry, Booth Hall of Children’s Hospital, Blackley, Manchester, M9 7AA UK
| | - Stephen J. Guter
- Department of Psychiatry, Institute for Juvenile Research, University of Illinois at Chicago, Chicago, IL 60612 USA
| | - Hakon Hakonarson
- The Center for Applied Genomics, Division of Human Genetics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
- Department of Pediatrics, Children’s Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA 19104 USA
| | - Richard Holt
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Gillian Hughes
- Autism Genetics Group, Department of Psychiatry, School of Medicine, Trinity College, Dublin 8, Ireland
| | - Vanessa Hus
- Autism and Communicative Disorders Centre, University of Michigan, Ann Arbor, MI 48109-2054 USA
| | - Roberta Igliozzi
- Stella Maris Institute for Child and Adolescent Neuropsychiatry, 56128 Calambrone, Pisa, Italy
| | - Cecilia Kim
- The Center for Applied Genomics, Division of Human Genetics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
| | - Sabine M. Klauck
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Alexander Kolevzon
- Department of Psychiatry, The Seaver Autism Center for Research and Treatment, Mount Sinai School of Medicine, New York, 10029 USA
| | - Janine A. Lamb
- Centre for Integrated Genomic Medical Research, University of Manchester, Manchester, M13 9PT UK
| | - Marion Leboyer
- INSERM U995, Department of Psychiatry, Groupe Hospitalier Henri Mondor-Albert Chenevier, AP-HP, University Paris 12, Fondation FondaMental, 94000 Créteil, France
| | - Ann Le Couteur
- Institute of Neuroscience, Newcastle University, Newcastle Upon Tyne, NE1 7RU UK
- Institute of Health and Society, Newcastle University, Newcastle Upon Tyne, NE1 7RU UK
| | - Bennett L. Leventhal
- Nathan Kline Institute for Psychiatric Research (NKI), 140 Old Orangeburg Road, Orangeburg, NY 10962 USA
- Department of Child and Adolescent Psychiatry, New York University, NYU Child Study Center, 550 First Avenue, New York, NY 10016 USA
| | - Catherine Lord
- Autism and Communicative Disorders Centre, University of Michigan, Ann Arbor, MI 48109-2054 USA
| | - Sabata C. Lund
- Department of Molecular Physiology and Biophysics, Vanderbilt Kennedy Center, Centers for Human Genetics Research and Molecular Neuroscience, Vanderbilt University, Nashville, TN 37232 USA
| | - Elena Maestrini
- Department of Biology, University of Bologna, 40126 Bologna, Italy
| | - Carine Mantoulan
- Octogone/CERPP (Centre d’Eudes et de Recherches en Psychopathologie), University de Toulouse Le Mirail, 31058 Toulouse Cedex, France
| | - Christian R. Marshall
- The Centre for Applied Genomics and Program in Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, ON M5G 1L7 Canada
| | - Helen McConachie
- Institute of Neuroscience, Newcastle University, Newcastle Upon Tyne, NE1 7RU UK
- Institute of Health and Society, Newcastle University, Newcastle Upon Tyne, NE1 7RU UK
| | | | - Jane McGrath
- Autism Genetics Group, Department of Psychiatry, School of Medicine, Trinity College, Dublin 8, Ireland
| | - William M. McMahon
- Psychiatry Department, University of Utah Medical School, Salt Lake City, UT 84108 USA
| | - Alison Merikangas
- Autism Genetics Group, Department of Psychiatry, School of Medicine, Trinity College, Dublin 8, Ireland
| | - Judith Miller
- Psychiatry Department, University of Utah Medical School, Salt Lake City, UT 84108 USA
| | | | - Ghazala K. Mirza
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Jeff Munson
- Department of Psychiatry and Behavioural Sciences, University of Washington, Seattle, WA 98195 USA
| | - Stanley F. Nelson
- Department of Human Genetics, University of California, Los Angeles School of Medicine, Los Angeles, CA 90095 USA
| | - Gudrun Nygren
- Gillberg Neuropsychiatry Centre, Sahlgrenska Academy, University of Gothenburg, S41345 Gothenburg, Sweden
| | | | | | - Katerina Papanikolaou
- University Department of Child Psychiatry, Athens University, Medical School, Agia Sophia Children’s Hospital, 115 27 Athens, Greece
| | - Jeremy R. Parr
- Institute of Neuroscience, Newcastle University, Newcastle Upon Tyne, NE1 7RU UK
- Institute of Health and Society, Newcastle University, Newcastle Upon Tyne, NE1 7RU UK
| | - Barbara Parrini
- Stella Maris Institute for Child and Adolescent Neuropsychiatry, 56128 Calambrone, Pisa, Italy
| | - Andrew Pickles
- Department of Medicine, School of Epidemiology and Health Science, University of Manchester, Manchester, M13 9PT UK
| | - Dalila Pinto
- The Centre for Applied Genomics and Program in Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, ON M5G 1L7 Canada
| | - Joseph Piven
- Carolina Institute for Developmental Disabilities, CB3366, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3366 USA
| | - David J. Posey
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Annemarie Poustka
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Fritz Poustka
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, J.W. Goethe University Frankfurt, 60528 Frankfurt, Germany
| | - Jiannis Ragoussis
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Bernadette Roge
- Octogone/CERPP (Centre d’Eudes et de Recherches en Psychopathologie), University de Toulouse Le Mirail, 31058 Toulouse Cedex, France
| | - Michael L. Rutter
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, London, SE5 8AF UK
| | - Ana F. Sequeira
- Instituto Nacional de Saude Dr Ricardo Jorge, Av Padre Cruz 1649-016, Lisbon, Portugal
- BioFIG, Center for Biodiversity, Functional and Integrative Genomics, Campus da FCUL, C2.2.12, Campo Grande, 1749-016 Lisbon, Portugal
- Instituto Gulbenkian de Cîencia, Rua Quinta Grande, 2780-156 Oeiras, Portugal
| | - Latha Soorya
- Department of Psychiatry, The Seaver Autism Center for Research and Treatment, Mount Sinai School of Medicine, New York, 10029 USA
| | - Inês Sousa
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Nuala Sykes
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Vera Stoppioni
- Neuropsichiatria Infantile, Ospedale Santa Croce, 61032 Fano, Italy
| | - Raffaella Tancredi
- Stella Maris Institute for Child and Adolescent Neuropsychiatry, 56128 Calambrone, Pisa, Italy
| | - Maïté Tauber
- Octogone/CERPP (Centre d’Eudes et de Recherches en Psychopathologie), University de Toulouse Le Mirail, 31058 Toulouse Cedex, France
| | - Ann P. Thompson
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Susanne Thomson
- Department of Molecular Physiology and Biophysics, Vanderbilt Kennedy Center, Centers for Human Genetics Research and Molecular Neuroscience, Vanderbilt University, Nashville, TN 37232 USA
| | - John Tsiantis
- University Department of Child Psychiatry, Athens University, Medical School, Agia Sophia Children’s Hospital, 115 27 Athens, Greece
| | - Herman Van Engeland
- Department of Child and Adolescent Psychiatry, University Medical Center, 3508 Utrecht, GA The Netherlands
| | - John B. Vincent
- Department of Psychiatry, Centre for Addiction and Mental Health, Clarke Institute, University of Toronto, Toronto, ON M5G 1X8 Canada
| | - Fred Volkmar
- Child Study Centre, Yale University, New Haven, CT 06520 USA
| | - Jacob A. S. Vorstman
- Department of Child and Adolescent Psychiatry, University Medical Center, 3508 Utrecht, GA The Netherlands
| | - Simon Wallace
- Department of Psychiatry, University of Oxford, Warneford Hospital, Headington, Oxford, OX3 7JX UK
| | - Kai Wang
- The Center for Applied Genomics, Division of Human Genetics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
| | - Thomas H. Wassink
- Department of Psychiatry, Carver College of Medicine, Iowa City, IA 52242 USA
| | - Kathy White
- Department of Psychiatry, University of Oxford, Warneford Hospital, Headington, Oxford, OX3 7JX UK
| | - Kirsty Wing
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Kerstin Wittemeyer
- Autism Centre for Education and Research, School of Education, University of Birmingham, Birmingham, B15 2TT UK
| | - Brian L. Yaspan
- Department of Molecular Physiology and Biophysics, Vanderbilt Kennedy Center, Centers for Human Genetics Research and Molecular Neuroscience, Vanderbilt University, Nashville, TN 37232 USA
| | - Lonnie Zwaigenbaum
- Department of Pediatrics, University of Alberta, Edmonton, AB T6G 2J3 Canada
| | - Catalina Betancur
- INSERM U952 and CNRS UMR 7224, UPMC Univ Paris 06, Paris, 75005 France
| | - Joseph D. Buxbaum
- Department of Psychiatry, The Seaver Autism Center for Research and Treatment, Mount Sinai School of Medicine, New York, 10029 USA
- Departments of Genetics and Genomic Sciences and Neuroscience, Mount Sinai School of Medicine, New York, 10029 USA
- Department of Neuroscience, Mount Sinai School of Medicine, New York, 10029 USA
| | - Rita M. Cantor
- Department of Human Genetics, University of California, Los Angeles School of Medicine, Los Angeles, CA 90095 USA
| | - Edwin H. Cook
- Department of Psychiatry, Institute for Juvenile Research, University of Illinois at Chicago, Chicago, IL 60612 USA
| | - Hilary Coon
- Psychiatry Department, University of Utah Medical School, Salt Lake City, UT 84108 USA
| | - Michael L. Cuccaro
- The John P. Hussman Institute for Human Genomics, University of Miami School of Medicine, Miami, FL 33136 USA
| | - Daniel H. Geschwind
- Department of Neurology, Center for Autism Research and Treatment, Program in Neurogenetics, Semel Institute, David Geffen School of Medicine at UCLA, Los Angeles, USA
| | - Jonathan L. Haines
- Department of Molecular Physiology and Biophysics, Vanderbilt Kennedy Center, Centers for Human Genetics Research and Molecular Neuroscience, Vanderbilt University, Nashville, TN 37232 USA
| | - Joachim Hallmayer
- Department of Psychiatry, Division of Child and Adolescent Psychiatry and Child Development, Stanford University School of Medicine, Stanford, CA 94304 USA
| | - Anthony P. Monaco
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - John I. Nurnberger
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Margaret A. Pericak-Vance
- The John P. Hussman Institute for Human Genomics, University of Miami School of Medicine, Miami, FL 33136 USA
| | - Gerard D. Schellenberg
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Pennsylvania, 19104 USA
| | - Stephen W. Scherer
- The Centre for Applied Genomics and Program in Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, ON M5G 1L7 Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A1 Canada
| | - James S. Sutcliffe
- Department of Molecular Physiology and Biophysics, Vanderbilt Kennedy Center, Centers for Human Genetics Research and Molecular Neuroscience, Vanderbilt University, Nashville, TN 37232 USA
| | - Peter Szatmari
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Veronica J. Vieland
- Battelle Center for Mathematical Medicine, The Research Institute at Nationwide Children’s Hospital and The Ohio State University, Columbus, OH 43205 USA
| | - Ellen M. Wijsman
- Department of Biostatistics, University of Washington, Seattle, WA 98195 USA
- Department of Medicine, University of Washington, Seattle, WA 98195 USA
| | - Andrew Green
- School of Medicine and Medical Science University College, Dublin 4, Ireland
| | - Michael Gill
- Autism Genetics Group, Department of Psychiatry, School of Medicine, Trinity College, Dublin 8, Ireland
| | - Louise Gallagher
- Autism Genetics Group, Department of Psychiatry, School of Medicine, Trinity College, Dublin 8, Ireland
| | - Astrid Vicente
- Instituto Nacional de Saude Dr Ricardo Jorge, Av Padre Cruz 1649-016, Lisbon, Portugal
- BioFIG, Center for Biodiversity, Functional and Integrative Genomics, Campus da FCUL, C2.2.12, Campo Grande, 1749-016 Lisbon, Portugal
- Instituto Gulbenkian de Cîencia, Rua Quinta Grande, 2780-156 Oeiras, Portugal
| | - Sean Ennis
- School of Medicine and Medical Science University College, Dublin 4, Ireland
- Health Sciences Centre, University College Dublin, Dublin, Ireland
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35
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Graw SL, Swisshelm K, Floyd K, Carstens BJ, Wamboldt MZ, Ross RG, Leonard S. Isochromosome 13 in a patient with childhood-onset schizophrenia, ADHD, and motor tic disorder. Mol Cytogenet 2012; 5:2. [PMID: 22214315 PMCID: PMC3274485 DOI: 10.1186/1755-8166-5-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 01/03/2012] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND A small percentage of all cases of schizophrenia have a childhood onset. The impact on the individual and family can be devastating. We report the results of genetic analyses from a patient with onset of visual hallucinations at 5 years, and a subsequent diagnosis at 9 years of schizophrenia, attention deficit hyperactivity disorder (ADHD) with hyperactivity and impulsivity, and chronic motor tic disorder. RESULTS Karyotypic analysis found 45,XX,i(13)(q10) in all cells examined. Alpha satellite FISH of isochromosome 13 revealed a large unsplit centromeric region, interpreted as two centromeres separated by minimal or undetectable short-arm material or as a single monocentric centromere, indicating that the isochromosome likely formed post-zygotically by a short arm U-type or centromeric exchange. Characterization of chromosome 13 simple tandem repeats and Affymetrix whole-genome 6.0 SNP array hybridization found homozygosity for all markers, and the presence of only a single paternal allele in informative markers, consistent with an isodisomic isochromosome of paternal origin. Analysis of two chromosome 13 schizophrenia candidate genes, D-amino acid oxidase activator (DAOA) and 5-hydroxytryptamine (serotonin) receptor 2A (5-HTR2A), failed to identify non-synonymous coding mutations but did identify homozygous risk polymorphisms. CONCLUSIONS We report a female patient with childhood-onset schizophrenia, ADHD, and motor tic disorder associated with an isodisomic isochromosome 13 of paternal origin and a 45,XX,i(13)(q10q10) karyotype. We examined two potential mechanisms to explain chromosome 13 involvement in the patient's pathology, including reduction to homozygosity of a paternal mutation and reduction to homozygosity of a paternal copy number variation, but were unable to identify any overtly pathogenic abnormality. Future studies may consider whether epigenetic mechanisms resulting from uniparental disomy (UPD) and the lack of chromosome 13 maternal alleles lead to the patient's features.
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Affiliation(s)
- Sharon L Graw
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO, USA
| | - Karen Swisshelm
- Colorado Genetics Laboratory, Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Kirsten Floyd
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO, USA
| | - Billie J Carstens
- Colorado Genetics Laboratory, Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Marianne Z Wamboldt
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO, USA
- Department of Psychiatry and Behavioral Science, Children's Hospital Colorado, Aurora, CO, USA
| | - Randall G Ross
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO, USA
| | - Sherry Leonard
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO, USA
- Research Division, Veterans Affairs Medical Research Service, Denver, CO, USA
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Araud T, Graw S, Berger R, Lee M, Neveu E, Bertrand D, Leonard S. The chimeric gene CHRFAM7A, a partial duplication of the CHRNA7 gene, is a dominant negative regulator of α7*nAChR function. Biochem Pharmacol 2011; 82:904-14. [PMID: 21718690 PMCID: PMC3162115 DOI: 10.1016/j.bcp.2011.06.018] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 06/10/2011] [Accepted: 06/13/2011] [Indexed: 12/11/2022]
Abstract
The human α7 neuronal nicotinic acetylcholine receptor gene (CHRNA7) is a candidate gene for schizophrenia and an important drug target for cognitive deficits in the disorder. Activation of the α7*nAChR, results in opening of the channel and entry of mono- and divalent cations, including Ca(2+), that presynaptically participates to neurotransmitter release and postsynaptically to down-stream changes in gene expression. Schizophrenic patients have low levels of α7*nAChR, as measured by binding of the ligand [(125)I]-α-bungarotoxin (I-BTX). The structure of the gene, CHRNA7, is complex. During evolution, CHRNA7 was partially duplicated as a chimeric gene (CHRFAM7A), which is expressed in the human brain and elsewhere in the body. The association between a 2bp deletion in CHRFAM7A and schizophrenia suggested that this duplicate gene might contribute to cognitive impairment. To examine the putative contribution of CHRFAM7A on receptor function, co-expression of α7 and the duplicate genes was carried out in cell lines and Xenopus oocytes. Expression of the duplicate alone yielded protein expression but no functional receptor and co-expression with α7 caused a significant reduction of the amplitude of the ACh-evoked currents. Reduced current amplitude was not correlated with a reduction of I-BTX binding, suggesting the presence of non-functional (ACh-silent) receptors. This hypothesis is supported by a larger increase of the ACh-evoked current by the allosteric modulator 1-(5-chloro-2,4-dimethoxy-phenyl)-3-(5-methyl-isoxazol-3-yl)-urea (PNU-120596) in cells expressing the duplicate than in the control. These results suggest that CHRFAM7A acts as a dominant negative modulator of CHRNA7 function and is critical for receptor regulation in humans.
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Affiliation(s)
- Tanguy Araud
- Department of Neurosciences Medical Faculty, University of Geneva, Geneva, Switzerland.
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Liao J, DeWard SJ, Madan-Khetarpal S, Surti U, Hu J. A small homozygous microdeletion of 15q13.3 including the CHRNA7 gene in a girl with a spectrum of severe neurodevelopmental features. Am J Med Genet A 2011; 155A:2795-800. [PMID: 21990074 DOI: 10.1002/ajmg.a.34237] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Accepted: 07/10/2011] [Indexed: 11/08/2022]
Abstract
A broad spectrum of neurodevelopmental and psychiatric disorders with variable expressivity has been reported to be associated with 15q13.3 heterozygous microdeletions. Using oligonucleotide-based array-CGH analysis, we identified a small homozygous 15q13.3 deletion in a 6-year-old girl with significant global developmental delay, severe hypotonia, cortical visual impairment, staring spell seizure, and abnormal electroencephalogram. She inherited this deletion from both parents, each of them being a heterozygous carrier. With a minimum size of 410 kb, it is the smallest 15q13.3 homozygous microdeletion reported to date and contains only the CHRNA7 gene. By comparing the phenotype of our patient with that of the other four previously reported cases with larger homozygous or compound heterozygous deletions, we conclude that patients with homozygous deletion of 15q13.3 have consistent clinical features and loss of CHRNA7 gene alone is sufficient to cause the majority of clinical features found in these patients.
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Affiliation(s)
- Jun Liao
- Pittsburgh Cytogenetics Laboratory, Center for Medical Genetics and Genomics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
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Evidence for association of the non-duplicated region of CHRNA7 gene with bipolar disorder but not with Schizophrenia. Psychiatr Genet 2011; 20:289-97. [PMID: 20463630 DOI: 10.1097/ypg.0b013e32833a9b7a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Biological evidence in both human and animal studies suggests α7 neuronal nicotinic acetylcholine receptor subunit gene (CHRNA7) as a suitable functional candidate for genetic studies in psychiatric populations. This gene maps to chromosome 15q13-14, a major linkage hotspot for schizophrenia (SCH) and bipolar disorder (BD). In this study we examine the role of CHRNA7 in influencing the risk of SCH and BD. METHODS In the present investigation four SNPs of the non-duplicated region of CHRNA7 were genotyped: -86C/T variant, located in the 5'-upstream regulatory region; and three intronic polymorphisms (rs883473, rs6494223 and rs904952). Genetic analysis was performed on 510 patients diagnosed with SCH, 245 with BD and on 793 unrelated healthy controls. RESULTS SNP analysis suggested a significant difference in -86C/T allele (P=0.025) and genotype (P=0.03) frequencies between BD and control groups, although significance was lost after correction for multiple testing. Besides, the nucleotide change (T) in rs6494223 had a protective effect against BD [odds ratio (OR)=0.70 (0.57-0.87); P=0.001]. Genotype frequencies also showed significant association (P=0.001) [CT genotype OR=0.71 (0.5-0.96); TT genotype OR=0.47 (0.29-0.77)]. Haplotypic analysis revealed a positive association of the gene with BD (global-stat=24.18, P value=0.007) with a maximum effect in the region that covered introns 3 and 4. In contrast, no evidence of risk variants was found in the analysis of the SCH sample. CONCLUSION Our data support the non-duplicated region of CHRNA7 gene as a susceptibility region for BD but not for SCH. Further genotyping of this region may help to delimit the causal polymorphism.
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Leung KN, Chamberlain SJ, Lalande M, LaSalle JM. Neuronal chromatin dynamics of imprinting in development and disease. J Cell Biochem 2011; 112:365-73. [PMID: 21268055 DOI: 10.1002/jcb.22958] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Epigenetic mechanisms play essential roles in mammalian neurodevelopment and genetic mutations or chromosomal deletions or duplications of epigenetically regulated loci or pathways result in several important human neurodevelopmental disorders. Postnatal mammalian neurons have among the most structured and dynamic nuclear organization of any cell type. Human chromosome 15q11-13 is an imprinted locus required for normal neurodevelopment and is regulated by a plethora of epigenetic mechanisms in neurons, including multiple noncoding RNAs, parentally imprinted transcription and histone modifications, large-scale chromatin decondensation, and homologous pairing in mature neurons of the mammalian brain. Here, we describe the multiple epigenetic layers regulating 15q11-13 gene expression and chromatin dynamics in neurons and propose a model of how noncoding RNAs may influence the unusual neuronal chromatin structure and dynamics at this locus. We also discuss the need for improved neuronal cell culture systems that model human 15q11-13 and other neurodevelopmental disorders with epigenetic bases in order to test the mechanisms of chromatin dynamics and nuclear organization in neurons. Induced pluripotent stem cells and other stem cell technologies hold promise for improved understanding of and therapeutic interventions for multiple human neurodevelopmental disorders.
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Affiliation(s)
- Karen N Leung
- Genome Center and Medical Microbiology and Immunology, School of Medicine, University of California, Davis, California 95616, USA
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Rosenfeld JA, Stephens LE, Coppinger J, Ballif BC, Hoo JJ, French BN, Banks VC, Smith WE, Manchester D, Tsai ACH, Merrion K, Mendoza-Londono R, Dupuis L, Schultz R, Torchia B, Sahoo T, Bejjani B, Weaver DD, Shaffer LG. Deletions flanked by breakpoints 3 and 4 on 15q13 may contribute to abnormal phenotypes. Eur J Hum Genet 2011; 19:547-54. [PMID: 21248749 DOI: 10.1038/ejhg.2010.237] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Non-allelic homologous recombination (NAHR) between segmental duplications in proximal chromosome 15q breakpoint (BP) regions can lead to microdeletions and microduplications. Several individuals with deletions flanked by BP3 and BP4 on 15q13, immediately distal to, and not including the Prader-Willi/Angelman syndrome (PW/AS) critical region and proximal to the BP4-BP5 15q13.3 microdeletion syndrome region, have been reported; however, because the deletion has also been found in normal relatives, the significance of these alterations is unclear. We have identified six individuals with deletions limited to the BP3-BP4 interval and an additional four individuals with deletions of the BP3-BP5 interval from 34 046 samples submitted for clinical testing by microarray-based comparative genomic hybridization (aCGH). Of four individuals with BP3-BP4 deletions for whom parental testing was conducted, two were apparently de novo and two were maternally inherited. A comparison of clinical features, available for five individuals in our study (four with deletions within BP3-BP4 and one with a BP3-BP5 deletion), with those in the literature show common features of short stature and/or failure to thrive, microcephaly, hypotonia, and premature breast development in some individuals. Although the BP3-BP4 deletion does not yet demonstrate statistically significant enrichment in abnormal populations compared with control populations, the presence of common clinical features among probands and the presence of genes with roles in development and nervous system function in the deletion region suggest that this deletion may have a role in abnormal phenotypes in some individuals.
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de Lucas-Cerrillo AM, Maldifassi MC, Arnalich F, Renart J, Atienza G, Serantes R, Cruces J, Sánchez-Pacheco A, Andrés-Mateos E, Montiel C. Function of partially duplicated human α77 nicotinic receptor subunit CHRFAM7A gene: potential implications for the cholinergic anti-inflammatory response. J Biol Chem 2010; 286:594-606. [PMID: 21047781 DOI: 10.1074/jbc.m110.180067] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The neuronal α7 nicotinic receptor subunit gene (CHRNA7) is partially duplicated in the human genome forming a hybrid gene (CHRFAM7A) with the novel FAM7A gene. The hybrid gene transcript, dupα7, has been identified in brain, immune cells, and the HL-60 cell line, although its translation and function are still unknown. In this study, dupα7 cDNA has been cloned and expressed in GH4C1 cells and Xenopus oocytes to study the pattern and functional role of the expressed protein. Our results reveal that dupα7 transcript was natively translated in HL-60 cells and heterologously expressed in GH4C1 cells and oocytes. Injection of dupα7 mRNA into oocytes failed to generate functional receptors, but when co-injected with α7 mRNA at α7/dupα7 ratios of 5:1, 2:1, 1:1, 1:5, and 1:10, it reduced the nicotine-elicited α7 current generated in control oocytes (α7 alone) by 26, 53, 75, 93, and 94%, respectively. This effect is mainly due to a reduction in the number of functional α7 receptors reaching the oocyte membrane, as deduced from α-bungarotoxin binding and fluorescent confocal assays. Two additional findings open the possibility that the dominant negative effect of dupα7 on α7 receptor activity observed in vitro could be extrapolated to in vivo situations. (i) Compared with α7 mRNA, basal dupα7 mRNA levels are substantial in human cerebral cortex and higher in macrophages. (ii) dupα7 mRNA levels in macrophages are down-regulated by IL-1β, LPS, and nicotine. Thus, dupα7 could modulate α7 receptor-mediated synaptic transmission and cholinergic anti-inflammatory response.
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Joo EJ, Lee KY, Kim HS, Kim SH, Ahn YM, Kim YS. Genetic Association Study of the Alpha 7 Nicotinic Receptor (CHRNA7) with the Development of Schizophrenia and Bipolar Disorder in Korean Population. Psychiatry Investig 2010; 7:196-201. [PMID: 20927308 PMCID: PMC2947807 DOI: 10.4306/pi.2010.7.3.196] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 06/06/2010] [Accepted: 07/04/2010] [Indexed: 01/29/2023] Open
Abstract
OBJECTIVE CHRNA7 has been shown to be a strong candidate gene for schizophrenia and bipolar disorder. It is located on chromosome 15q13-q14, which is one of the replicated linkage spots for schizophrenia and bipolar disorder. METHODS We conducted an association study to determine whether previous positive association is replicable in the Korean population. We included 254 patients with schizophrenia, 193 patients with bipolar disorder type I, 38 patients with bipolar disorder type II, 64 schizoaffective disorder patients, and 349 controls. All subjects were ethnically Korean. A total of 898 subjects were included, and genotyping was done for three single nucleotide polymorphisms (SNPs) of CHRNA7. These three intronic SNPs were rs2337506 (A/G), rs6494223 (C/T), and rs12916879 (A/G). RESULTS There was only one marginally significant association; this association was between rs12916879 and bipolar disorder type I in the male subgroup. In both the allele and genotype distributions, we found a weak signal (Chi-squared=3.57, df=1, p=0.06 for allele, Chi-squared=7.50, df=2, p=0.02 for genotype) only. Unphased haplotype analysis could not provide additional support for this finding. No SNP was associated with schizophrenia or any other affected groups in this Korean sample. The associative finding is marginal and inconclusive. CONCLUSION We could not replicate positive association in other ethnic groups previously studied. This suggests possible heterogeneity in the genes associated with schizophrenia and bipolar disorders. Because of structural complexity of the CHRNA7 gene and the limited statistical power of this study, further genetic studies with more SNPs and larger samples covering various populations, along with more fine molecular exploration of the CHRNA7 gene structure, are required.
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Affiliation(s)
- Eun-Jeong Joo
- Department of Neuropsychiatry, Eulji University School of Medicine, Eulji General Hospital, Seoul, Korea
| | - Kyu Young Lee
- Department of Neuropsychiatry, Eulji University School of Medicine, Eulji General Hospital, Seoul, Korea
| | - Hyun Sook Kim
- College of Nursing, Eulji University, Seongnam, Korea
| | - Se Hyun Kim
- Department of Psychiatry and Behavioral Science, Seoul National University College of Medicine, Seoul, Korea
- Institute of Human Behavioral Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Yong Min Ahn
- Department of Psychiatry and Behavioral Science, Seoul National University College of Medicine, Seoul, Korea
| | - Yong Sik Kim
- Department of Psychiatry and Behavioral Science, Seoul National University College of Medicine, Seoul, Korea
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Lepichon JB, Bittel DC, Graf WD, Yu S. A 15q13.3 homozygous microdeletion associated with a severe neurodevelopmental disorder suggests putative functions of the TRPM1, CHRNA7, and other homozygously deleted genes. Am J Med Genet A 2010; 152A:1300-4. [PMID: 20425840 DOI: 10.1002/ajmg.a.33374] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We identified a novel homozygous 15q13.3 microdeletion in a young boy with a complex neurodevelopmental disorder characterized by severe visual impairment, hypotonia, profound intellectual disability, and refractory epilepsy. The homozygous deletion of the genes within this deleted region provides a useful insight into the pathogenesis of the observed clinical phenotype. Absence of the Transient Receptor Potential Cation Channel, Subfamily M, Member 1 (TRPM1) gene product is proposed as a possible mechanism for the severe visual impairment; absence of CHRNA7 (alpha7-nicotinic receptor subunit) as a cause of the refractory seizures and severe cognitive impairment; and deletion of MTMR10 and/or MTMR15 (encoding myotubularin related proteins) alone or combined with other homozygously deleted genes as a cause for the congenital hypotonia with areflexia. The distinctive clinical findings in this patient reveal potential functions of the genes within the deleted region.
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Affiliation(s)
- Jean-Baptiste Lepichon
- Section of Neurology, Children's Mercy Hospitals and Clinics, University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA
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Amar S, Ovadia O, Maier W, Ebstein R, Belmaker RH, Mishmar D, Agam G. Copy number variation of the SELENBP1 gene in schizophrenia. Behav Brain Funct 2010; 6:40. [PMID: 20615253 PMCID: PMC2915948 DOI: 10.1186/1744-9081-6-40] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Accepted: 07/08/2010] [Indexed: 12/12/2022] Open
Abstract
Background Schizophrenia is associated with rare copy-number (CN) mutations. Screening for such alleles genome-wide, though comprehensive, cannot study in-depth the causality of particular loci, therefore cannot provide the functional interpretation for the disease etiology. We hypothesized that CN mutations in the SELENBP1 locus could associate with the disorder and that these mutations could alter the gene product's activity in patients. Methods We analyzed SELENBP1 CN variation (CNV) in blood DNA from 49 schizophrenia patients and 49 controls (cohort A). Since CN of genes may vary among tissues, we investigated SELENBP1 CN in age- sex- and postmortem interval-matched cerebellar DNA samples from 14 patients and 14 controls (cohort B). Since CNV may either be de-novo or inherited we analyzed CNV of the SELENBP1 locus in blood DNA from 26 trios of schizophrenia probands and their healthy parents (cohort C). SELENBP1 mRNA levels were measured by real-time PCR. Results In cohort A reduced CN of the SELENBP1 locus was found in four patients but in none of the controls. In cohort B we found reduced CN of the SELENBP1 locus in two patients but in none of the controls. In cohort C three patients exhibited drastic CN reduction, not present in their parents, indicating de-novo mutation. A reduction in SELENBP1 mRNA levels in the postmortem cerebellar samples of schizophrenia patients was found. Conclusions We report a focused study of CN mutations in the selenium binding-protein1 (SELENBP1) locus previously linked with schizophrenia. We provide evidence for recurrence of decreased CN of the SELENBP1 locus in three unrelated patients' cohorts but not in controls, raising the possibility of functional involvement of these mutations in the etiology of the disease.
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Affiliation(s)
- Shirly Amar
- Psychiatry Research Unit, Faculty of Health Sciences, Ben-Gurion University of the Negev, and Mental Health Center, Beersheva, Israel
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Strong synaptic transmission impact by copy number variations in schizophrenia. Proc Natl Acad Sci U S A 2010; 107:10584-9. [PMID: 20489179 DOI: 10.1073/pnas.1000274107] [Citation(s) in RCA: 166] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Schizophrenia is a psychiatric disorder with onset in late adolescence and unclear etiology characterized by both positive and negative symptoms, as well as cognitive deficits. To identify copy number variations (CNVs) that increase the risk of schizophrenia, we performed a whole-genome CNV analysis on a cohort of 977 schizophrenia cases and 2,000 healthy adults of European ancestry who were genotyped with 1.7 million probes. Positive findings were evaluated in an independent cohort of 758 schizophrenia cases and 1,485 controls. The Gene Ontology synaptic transmission family of genes was notably enriched for CNVs in the cases (P = 1.5 x 10(-7)). Among these, CACNA1B and DOC2A, both calcium-signaling genes responsible for neuronal excitation, were deleted in 16 cases and duplicated in 10 cases, respectively. In addition, RET and RIT2, both ras-related genes important for neural crest development, were significantly affected by CNVs. RET deletion was exclusive to seven cases, and RIT2 deletions were overrepresented common variant CNVs in the schizophrenia cases. Our results suggest that novel variations involving the processes of synaptic transmission contribute to the genetic susceptibility of schizophrenia.
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Ross RG, Stevens KE, Proctor WR, Leonard S, Kisley MA, Hunter SK, Freedman R, Adams CE. Research review: Cholinergic mechanisms, early brain development, and risk for schizophrenia. J Child Psychol Psychiatry 2010; 51:535-49. [PMID: 19925602 PMCID: PMC2862788 DOI: 10.1111/j.1469-7610.2009.02187.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The onset of diagnostic symptomology for neuropsychiatric diseases is often the end result of a decades-long process of aberrant brain development. Identification of novel treatment strategies aimed at normalizing early brain development and preventing mental illness should be a major therapeutic goal. However, there are few models for how this goal might be achieved. This review uses the development of a psychophysiological correlate of attentional deficits in schizophrenia to propose a developmental model with translational primary prevention implications. Review of genetic and neurobiological studies suggests that an early interaction between alpha7 nicotinic receptor density and choline availability may contribute to the development of schizophrenia-associated attentional deficits. Therapeutic implications, including perinatal dietary choline supplementation, are discussed.
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Affiliation(s)
- Randal G Ross
- Department of Psychiatry, University of Colorado Denver, Aurora, CO, USA
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Masurel-Paulet A, Andrieux J, Callier P, Cuisset JM, Le Caignec C, Holder M, Thauvin-Robinet C, Doray B, Flori E, Alex-Cordier MP, Beri M, Boute O, Delobel B, Dieux A, Vallee L, Jaillard S, Odent S, Isidor B, Beneteau C, Vigneron J, Bilan F, Gilbert-Dussardier B, Dubourg C, Labalme A, Bidon C, Gautier A, Pernes P, Pinoit JM, Huet F, Mugneret F, Aral B, Jonveaux P, Sanlaville D, Faivre L. Delineation of 15q13.3 microdeletions. Clin Genet 2010; 78:149-61. [PMID: 20236110 DOI: 10.1111/j.1399-0004.2010.01374.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The increasing use of array-comparative genomic hybridization (array-CGH) to identify copy number variations (CNVs) in patients with developmental delay (DD), mental retardation and/or dysmorphic features has allowed the recent recognition of numerous genomic imbalances, including the 15q13.3 microdeletion. Patients with this microdeletion generally present with relatively consistent breakpoints at BP4 and BP5, which include the CHRNA7 gene. About 100 index cases have been reported since the first publication in 2008. This large number of patients ascertained through highly variable samples has been necessary to describe the full phenotypic spectrum of this microdeletion, ranging from mental retardation with dysmorphic features, epilepsy, neuropsychiatric disturbances with or without cognitive impairment to complete absence of anomalies. Here, we describe a collaborative study reporting a new cohort of 12 index patients and 13 relatives carrying a heterozygous BP4-BP5 microdeletion out of a series of 4625 patients screened by array-CGH for DD. We confirm the clinical expressivity of the disease as well as the incomplete penetrance in seven families. We showed through a review of the literature that males are more likely to be symptomatic. Sequence analysis of CHRNA7 yielded no data to support the unmasking of recessive variants as a cause of phenotypic variability. We also report the first patient carrying a 15q13.3 homozygous microdeletion inherited from both parents. He had severe epileptic encephalopathy with retinopathy, autistic features and choreoathetosis. Besides the classical approximately 1.5 Mb BP4-BP5 microdeletion, we also describe three index patients and two relatives with a smaller 500 kb microdeletion, including the CHRNA7 gene.
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Affiliation(s)
- A Masurel-Paulet
- Centre de Génétique et Centre de Référence Anomalies du développement et syndromes malformatifs, Hôpital d'Enfants, CHU, Dijon
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Patterson JV, Sandman CA, Ring A, Jin Y, Bunney WE. An initial report of a new biological marker for bipolar disorder: P85 evoked brain potential. Bipolar Disord 2009; 11:596-609. [PMID: 19689502 DOI: 10.1111/j.1399-5618.2009.00734.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Progress toward understanding the neurobiological and genetic underpinnings of bipolar disorder has been limited by the scarcity of potential biological markers that predict its occurrence. A measure of the integrity of brain inhibitory function, sensory gating, measured using the amplitude of the evoked potential at 50 ms to the first of two paired clicks divided by the response to the second, has been characterized as a biological marker for schizophrenia. Currently, no such biological marker exists for bipolar disorder. The goal of this research was to determine how gating of an auditory brain potential at 85 ms (P85), not previously examined in sensory gating studies, differentiated control and patient groups. METHODS P50 and P85 auditory evoked potentials were collected from individuals diagnosed with schizoaffective disorder (n = 45), paranoid schizophrenia (n = 66), and bipolar I disorder (n = 42) using DSM-IV criteria and the Structured Clinical Interview for DSM-IV; and from 56 healthy controls. RESULTS The P85 gating ratio was significantly larger in the bipolar disorder group compared to each of the other groups (F(3,204) = 5.47, p = 0.001, and post-hoc tests). The P50 gating ratio was significantly larger for the schizoaffective group than for the control group (F(3,204) = 2.81, p = 0.040), but did not differ from the ratio for the schizophrenia, paranoid type (p = 0.08) and bipolar groups. CONCLUSIONS The previously unstudied P85 gating ratio may provide a new marker specific to bipolar disorder. The findings will promote further studies to investigate the unique contribution of this measure as an endophenotype.
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Affiliation(s)
- Julie V Patterson
- Department of Psychiatry and Human Behavior, University of California at Irvine, Irvine, California 92868, USA.
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Dome P, Lazary J, Kalapos MP, Rihmer Z. Smoking, nicotine and neuropsychiatric disorders. Neurosci Biobehav Rev 2009; 34:295-342. [PMID: 19665479 DOI: 10.1016/j.neubiorev.2009.07.013] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 07/23/2009] [Accepted: 07/30/2009] [Indexed: 12/20/2022]
Abstract
Tobacco smoking is an extremely addictive and harmful form of nicotine (NIC) consumption, but unfortunately also the most prevalent. Although disproportionately high frequencies of smoking and its health consequences among psychiatric patients are widely known, the neurobiological background of this epidemiological association is still obscure. The diverse neuroactive effects of NIC and some other major tobacco smoke constituents in the central nervous system may underlie this association. This present paper summarizes the pharmacology of NIC and its receptors (nAChR) based on a systematic review of the literature. The role of the brain's reward system(s) in NIC addiction and the results of functional and structural neuroimaging studies on smoking-related states and behaviors (i.e. dependence, craving, withdrawal) are also discussed. In addition, the epidemiological, neurobiological, and genetic aspects of smoking in several specific neuropsychiatric disorders are reviewed and the clinical relevance of smoking in these disease states addressed.
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Affiliation(s)
- Peter Dome
- Department of Clinical and Theoretical Mental Health, Kutvolgyi Clinical Center, Semmelweis University, Faculty of Medicine, Kutvolgyi ut 4, 1125 Budapest, Hungary.
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Alaerts M, Del-Favero J. Searching genetic risk factors for schizophrenia and bipolar disorder: learn from the past and back to the future. Hum Mutat 2009; 30:1139-52. [DOI: 10.1002/humu.21042] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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