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Li X, Ma S, Yan W, Wu Y, Kong H, Zhang M, Luo X, Xia J. dbBIP: a comprehensive bipolar disorder database for genetic research. Database (Oxford) 2022; 2022:6627538. [PMID: 35779245 PMCID: PMC9250320 DOI: 10.1093/database/baac049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/28/2022] [Accepted: 06/11/2022] [Indexed: 11/17/2022]
Abstract
Bipolar disorder (BIP) is one of the most common hereditary psychiatric disorders worldwide. Elucidating the genetic basis of BIP will play a pivotal role in mechanistic delineation. Genome-wide association studies (GWAS) have successfully reported multiple susceptibility loci conferring BIP risk, thus providing insight into the effects of its underlying pathobiology. However, difficulties remain in the extrication of important and biologically relevant data from genetic discoveries related to psychiatric disorders such as BIP. There is an urgent need for an integrated and comprehensive online database with unified access to genetic and multi-omics data for in-depth data mining. Here, we developed the dbBIP, a database for BIP genetic research based on published data. The dbBIP consists of several modules, i.e.: (i) single nucleotide polymorphism (SNP) module, containing large-scale GWAS genetic summary statistics and functional annotation information relevant to risk variants; (ii) gene module, containing BIP-related candidate risk genes from various sources and (iii) analysis module, providing a simple and user-friendly interface to analyze one’s own data. We also conducted extensive analyses, including functional SNP annotation, integration (including summary-data-based Mendelian randomization and transcriptome-wide association studies), co-expression, gene expression, tissue expression, protein–protein interaction and brain expression quantitative trait loci analyses, thus shedding light on the genetic causes of BIP. Finally, we developed a graphical browser with powerful search tools to facilitate data navigation and access. The dbBIP provides a comprehensive resource for BIP genetic research as well as an integrated analysis platform for researchers and can be accessed online at http://dbbip.xialab.info. Database URL: http://dbbip.xialab.info
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Affiliation(s)
- Xiaoyan Li
- Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education and Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University , 111 Jiulong Road, Shushan District, Hefei, Anhui 230601, China
| | - Shunshuai Ma
- Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education and Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University , 111 Jiulong Road, Shushan District, Hefei, Anhui 230601, China
| | - Wenhui Yan
- Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education and Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University , 111 Jiulong Road, Shushan District, Hefei, Anhui 230601, China
| | - Yong Wu
- Affiliated Wuhan Mental Health Center, Tongji Medical College, Huazhong University of Science and Technology , 93 Youyi Road, Qiaokou District, Wuhan, Hubei 430030, China
| | - Hui Kong
- Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education and Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University , 111 Jiulong Road, Shushan District, Hefei, Anhui 230601, China
| | - Mingshan Zhang
- Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education and Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University , 111 Jiulong Road, Shushan District, Hefei, Anhui 230601, China
| | - Xiongjian Luo
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences , 32 Jiaochang East Road, Wuhua District, Kunming, Yunnan 650223, China
- Kunming College of Life Science, University of Chinese Academy of Sciences , 19 Qingsong Road, Panlong District, Kunming, Yunnan 650204, China
| | - Junfeng Xia
- Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education and Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University , 111 Jiulong Road, Shushan District, Hefei, Anhui 230601, China
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Majeed A, Xiong J, Teopiz KM, Ng J, Ho R, Rosenblat JD, Phan L, Cao B, McIntyre RS. Efficacy of dextromethorphan for the treatment of depression: a systematic review of preclinical and clinical trials. Expert Opin Emerg Drugs 2021; 26:63-74. [PMID: 33682569 DOI: 10.1080/14728214.2021.1898588] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION The large percentage of adults with major depressive disorder (MDD) insufficiently responding and/or tolerating conventional monoamine-based antidepressants invites the need for mechanistically novel treatments. Convergent evidence implicates glutamatergic signaling as a potential therapeutic target in MDD. AREAS COVERED The synthesis herein of preclinical and clinical studies indicates that dextromethorphan (DXM) is well tolerated and exhibits clinically significant antidepressant effects; DXM combined with bupropion has demonstrated replicated and relatively rapid onset efficacy in adults with MDD. DXM efficacy has been preliminarily reported in adults with bipolar depression. The combination of DXM and bupropion represents a pharmacokinetic and pharmacodynamic synergy which may account for the rapidity of action in MDD. EXPERT OPINION The combination of DXM and bupropion is a safe, well tolerated and efficacious treatment option in adults with MDD. Priority questions are whether DXM/bupropion is uniquely effective across discrete domains of psychopathology (e.g. anhedonia, reward processing, general cognitive systems) and/or whether it is able to significantly improve patient-reported outcomes (e.g. quality of life, psychosocial functioning). The availability of ketamine/esketamine and DXM/bupropion instantiates the relevance of glutamate as a treatment target in MDD. Studies in bipolar depression with DXM/bupropion are warranted as well as in MDD with suicidality.
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Affiliation(s)
- Amna Majeed
- Temerty Faculty of Medicine, University of Toronto, Canada
| | - Jiaqi Xiong
- Department of Pharmacology, University of Toronto, Toronto, Canada
| | - Kayla M Teopiz
- Institute of Medical Science, University of Toronto, Toronto, Canada
| | - Jason Ng
- Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, Canada
| | - Roger Ho
- Institute for Health Innovation and Technology (Ihealthtech), National University of Singapore, Singapore, Singapore.,Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Joshua D Rosenblat
- Department of Pharmacology, University of Toronto, Toronto, Canada.,Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, Canada
| | - Lee Phan
- Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, Canada
| | - Bing Cao
- Key Laboratory of Cognition and Personality, Faculty of Psychology, Ministry of Education, Southwest University (SWU), P. R. China
| | - Roger S McIntyre
- Department of Pharmacology, University of Toronto, Toronto, Canada.,Institute of Medical Science, University of Toronto, Toronto, Canada.,Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, Canada.,Brain and Cognition Discovery Foundation, Toronto, Canada
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Kempisty B, Bober A, Łuczak M, Czerski P, Szczepankiewicz A, Hauser J, Jagodziński PP. Distribution of 1298A > C polymorphism of methylenetetrahydrofolate reductase gene in patients with bipolar disorder and schizophrenia. Eur Psychiatry 2020; 22:39-43. [PMID: 17188847 DOI: 10.1016/j.eurpsy.2006.11.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Revised: 11/02/2006] [Accepted: 11/10/2006] [Indexed: 01/29/2023] Open
Abstract
AbstractWe investigated the genotype frequency of methylenetetrahydrofolate reductase (MTHFR) 1298A > C polymorphism in the group of patients with bipolar disorder type I (BDI) (n = 200) and schizophrenia (n = 200) and in the control group (n = 300). Odds ratio (OR) for patients with BD and schizophrenia in 1298CC homozygous state was 3.768 (95% CI = 1.752–8.104); P = 0.0003; (P = 0.0006 after Bonferroni correction) and 2.694; (95% CI = 1.207–6.013); P = 0.0123 (P = 0.0246 after Bonferroni correction), respectively. The stratification of patients based on gender revealed significant association of 1298CC genotype with female patients only with BDI (OR = 7.293; 95% CI = 2.017–26.363; P = 0.0005).Our results confirm association of BD and schizophrenia with the 1p36.3 MTHFR locus and with the methyl group transfer using folate-dependent one-carbon pathway.
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Affiliation(s)
- Bartosz Kempisty
- Department of Biochemistry and Molecular Biology, University of Medical Sciences, 6 Swiecickiego St., 60-781 Poznan, Poland
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Rao S, Han X, Shi M, Siu CO, Waye MMY, Liu G, Wing YK. Associations of the serotonin transporter promoter polymorphism (5-HTTLPR) with bipolar disorder and treatment response: A systematic review and meta-analysis. Prog Neuropsychopharmacol Biol Psychiatry 2019; 89:214-226. [PMID: 30217771 DOI: 10.1016/j.pnpbp.2018.08.035] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/30/2018] [Accepted: 08/31/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND Associations of the serotonin transporter promoter polymorphism (5-HTTLPR) with bipolar disorder (BPD) and treatment response in bipolar patients were not conclusive. This study not only assessed the association between the 5-HTTLPR and BPD with accumulating relevant studies, but also in the first time evaluated the effect of the 5-HTTLPR on both anti-depressive and anti-manic treatment responses in bipolar patients. METHODS PubMed, Embase, PsycINFO, Cochrane Library and Cochrane Control Trials databases were systematically searched before February 2017. This meta-analysis followed the PRISMA guidelines. RESULTS A total of 32 population-based studies (5567 cases and 6993 controls) and 9 family-based studies (837 trios) were finally screened out and statistically joined into a single meta-analysis that revealed an association between S allele and an increased risk of BPD (OR = 1.06, p = .038). Pooled analysis of the 32 population-based studies indicated an association of S-carrier genotypes with an increased risk of BPD (OR = 1.10, p = .029). Meanwhile, the association remained significant in Caucasians (OR = 1.15, p = .004), which could provide an enough power (88%) to detect a significant association. Regarding the treatment response studies, 6 studies reporting the relationship of the 5-HTTLPR in anti-depressive remission rate (1034 patients) and 7 studies reporting in response rate (1098 patients) were included for pooled analyses. We observed a significant association of S-carrier genotypes with a reduced anti-depressive remission rate (OR = 0.64, p = .006) but not with anti-depressive response rate. The association between the 5-HTTLPR with anti-manic response rate was not observed in the included 6 studies (676 patients). CONCLUSIONS The present study supported the presence of a marginal but detectable effect of the 5-HTTLPR on susceptibility to BPD. Moreover, the detected association in Caucasian was statistically reliable. Besides, the 5-HTTLPR was identified as a useful predictor for anti-depressive remission but not for anti-depressive or anti-manic response.
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Affiliation(s)
- Shitao Rao
- Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, N.T., Hong Kong, SAR, China; The Nethersole School of Nursing, Faculty of Medicine, The Chinese University of Hong Kong, N.T., Hong Kong, SAR, China
| | - Xinyu Han
- The Nethersole School of Nursing, Faculty of Medicine, The Chinese University of Hong Kong, N.T., Hong Kong, SAR, China; College of Food and Biological Engineering, Jimei University, Xiamen, Fujian, China
| | - Mai Shi
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, N.T., Hong Kong, SAR, China
| | - Cynthia O Siu
- COS & Associates Ltd., Central District, Hong Kong, SAR, China
| | - Mary Miu Yee Waye
- The Nethersole School of Nursing, Faculty of Medicine, The Chinese University of Hong Kong, N.T., Hong Kong, SAR, China
| | - Guangming Liu
- College of Food and Biological Engineering, Jimei University, Xiamen, Fujian, China.
| | - Yun Kwok Wing
- Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, N.T., Hong Kong, SAR, China.
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Tencomnao T, Sritharathikhun T, Suttirat S. Influence of demographic factors and serotonin transporter-linked polymorphic region (5-HTTLPR) variants on major depression in a northeastern Thai population. ASIAN BIOMED 2010; 4:893-9. [DOI: 10.2478/abm-2010-0117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Background: Several lines of evidence suggest that the serotonergic system may be involved in the etiology of major depressive disorder (MDD). Objective: Investigate a potential association between the functional polymorphism in the serotonin transporter-linked polymorphic region (5-HTTLPR) and MDD in a northeastern Thai population, and explore the involvement of demographic characteristics in this disorder. Methods: One hundred eighty seven patients with MDD and 207 healthy controls were recruited from the same geographical area into the study. The 5-HTTLPR genotypes were determined using polymerase chain reaction (PCR) and analyzed statically. Results: Significant demographic differences between the two groups were observed, which included age, marital status, occupation, educational background, income, and alcohol use. The allele frequencies of the 5- HTTLPR polymorphism in our studied population were relatively near those of Asian populations, especially Chinese, which was regarded as enormously distinct from those of Caucasians. Nevertheless, our present study found no significant association between this polymorphism and MDD with respect to either genotype distributions or allele frequencies. Conclusion: No involvement of the 5-HTTLPR polymorphism was suggested, but demographic features in MDD were highlighted with respect to this studied population.
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Sigitova E, Fišar Z, Hroudová J, Cikánková T, Raboch J. Biological hypotheses and biomarkers of bipolar disorder. Psychiatry Clin Neurosci 2017; 71:77-103. [PMID: 27800654 DOI: 10.1111/pcn.12476] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 10/04/2016] [Accepted: 10/25/2016] [Indexed: 02/06/2023]
Abstract
The most common mood disorders are major depressive disorders and bipolar disorders (BD). The pathophysiology of BD is complex, multifactorial, and not fully understood. Creation of new hypotheses in the field gives impetus for studies and for finding new biomarkers for BD. Conversely, new biomarkers facilitate not only diagnosis of a disorder and monitoring of biological effects of treatment, but also formulation of new hypotheses about the causes and pathophysiology of the BD. BD is characterized by multiple associations between disturbed brain development, neuroplasticity, and chronobiology, caused by: genetic and environmental factors; defects in apoptotic, immune-inflammatory, neurotransmitter, neurotrophin, and calcium-signaling pathways; oxidative and nitrosative stress; cellular bioenergetics; and membrane or vesicular transport. Current biological hypotheses of BD are summarized, including related pathophysiological processes and key biomarkers, which have been associated with changes in genetics, systems of neurotransmitter and neurotrophic factors, neuroinflammation, autoimmunity, cytokines, stress axis activity, chronobiology, oxidative stress, and mitochondrial dysfunctions. Here we also discuss the therapeutic hypotheses and mechanisms of the switch between depressive and manic state.
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Affiliation(s)
- Ekaterina Sigitova
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Zdeněk Fišar
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Jana Hroudová
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Tereza Cikánková
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Jiří Raboch
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
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Lee SY, Chen SL, Wang TY, Chang YH, Chen PS, Huang SY, Tzeng NS, Wang LJ, Lee IH, Chen KC, Yang YK, Lu RB. The COMT Val158Met Polymorphism Is Associated With Response to Add-on Dextromethorphan Treatment in Bipolar Disorder. J Clin Psychopharmacol 2017; 37:94-8. [PMID: 27930497 DOI: 10.1097/JCP.0000000000000633] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE/BACKGROUND We previously conducted a randomized, double-blind, controlled, 12-week study evaluating the effect of add-on dextromethorphan (DM), a noncompetitive N-methyl-D-aspartate receptor antagonist, on patients with bipolar disorder (BD) treated using valproate (VPA), which showed negative clinical differences. The genetic variation between each individual may be responsible for interindividual differences. The catechol-O-methyltransferase (COMT) gene has been a candidate gene for BD. In the current study, we investigated whether the COMT Val158Met polymorphism predicts treatment response to VPA + add-on DM and to VPA + placebo. METHODS/PROCEDURES Patients with BD (n = 309) undergoing regular VPA treatments were randomly assigned to groups given either add-on DM (30 mg/d) (n = 102), DM (60 mg/d) (n = 101), or placebo (n = 106) for 12 weeks. The Hamilton Depression Rating Scale and Young Mania Rating Scale were used to evaluate clinical response during weeks 0, 1, 2, 4, 8, and 12. The genotypes of the COMT Val158Met polymorphism were determined using polymerase chain reaction plus restriction fragment length polymorphism analysis. To adjust for within-subject dependence over repeated assessments, multiple linear regression with generalized estimating equation methods was used. FINDINGS/RESULTS When stratified by the COMT Val158Met genotypes, significantly greater decreases in Hamilton Depression Rating Scale scores were found in the VPA + DM (30 mg/d) group in patients with the Val/Met genotype (P = 0.008). CONCLUSIONS We conclude that the COMT Val158Met polymorphism may influence responses to DM (30 mg/d) by decreasing depressive symptoms in BD patients.
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Gurbuz O, Altinbas K, Oflezer C, Kurt E, Arslan D. Signs of bruxism and temporomandibular disorders among patients with bipolar disorder. Balkan J Dent Med 2017; 21:152-157. [DOI: 10.1515/bjdm-2017-0026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Background/Aim: There is an abundance of data regarding temporomandibular disorders (TMD) and bruxism specific to patients with bipolar disorder (BD). This study aimed to investigate the prevalence of TMD signs in subjects with and without BD. Material and Methods: The case group included 242 adult patients (103 men and 139 women) with BD and the control group included 187 subjects without BD (89 men and 98 women). The case and control groups were compared for the presence of bruxism and the signs of TMD including muscle and temporomandibular joint (TMJ) tenderness to palpation, limitation of maximum mouth opening, and TMJ sounds. Results: The frequency of at least one sign of TMD was significantly higher in patients with BD (191 ⁄242, 78.9%) than the control group (95 ⁄187, 50.8%) (p<0.001). Statistically significant differences were found between the case and control groups in terms of joint pain on palpation (p<0.05), masseter muscle pain on palpation (p<0.01), joint clicks (p<0.001) and limited mouth opening (p<0.001). Bruxism was significantly higher in patients with BD (49.6%) than the control group (19.8%) (p<0.001). Conclusions: Patients with BD appear to be more prone to having TMD signs and bruxism compared to the control group, but this comorbidity should be better understood by further studies.
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Abstract
Progress in understanding the role of monoamine neurotransmission in pathophysiology of neuropsychiatric disorders was made after the discovery of the mechanisms of action of psychoactive drugs, including monoamine oxidase (MAO) inhibitors. The increase in monoamine neurotransmitter availability, decrease in hydrogen peroxide production, and neuroprotective effects evoked by MAO inhibitors represent an important approach in the development of new drugs for the treatment of mental disorders and neurodegenerative diseases. New drugs are synthesized by acting as multitarget-directed ligands, with MAO, acetylcholinesterase, and iron chelation as targets. Basic information is summarized in this paper about the drug-induced regulation of monoaminergic systems in the brain, with a focus on MAO inhibition. Desirable effects of MAO inhibition include increased availability of monoamine neurotransmitters, decreased oxidative stress, decreased formation of neurotoxins, induction of pro-survival genes and antiapoptotic factors, and improved mitochondrial functions.
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Affiliation(s)
- Zdeněk Fišar
- Department of Psychiatry, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 11, 120 00 Prague 2, Czech Republic.
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Chrcanovic BR, Kisch J, Albrektsson T, Wennerberg A. Bruxism and dental implant treatment complications: a retrospective comparative study of 98 bruxer patients and a matched group. Clin Oral Implants Res 2016; 28:e1-e9. [PMID: 27009853 DOI: 10.1111/clr.12844] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2016] [Indexed: 11/29/2022]
Abstract
OBJECTIVES To analyze the complications of dental implant treatment in a group of patients with bruxism in comparison with a matched group of non-bruxers. MATERIAL AND METHODS Patients being diagnosed as bruxers were identified within a group of patients consecutively treated with implant-supported prostheses at one specialist clinic, based on the most recent listed sign and symptoms of bruxism according to the International Classification of Sleep Disorders. A diagnostic grading system of "possible," "probable," and "definite" sleep or awake bruxism was used, according to a recent published international consensus. A case-control matching model was used to match the bruxers with a group of non-bruxers, based on five variables. Implant-, prosthetic-, and patient-related data were collected, as well as 14 mechanical complications, and compared between groups. RESULTS Ninety-eight of 2670 patients were identified as bruxers. The odds ratio of implant failure in bruxers in relation to non-bruxers was 2.71 (95% CI 1.25, 5.88). Considering the same number of patients with the same total number of implants equally distributed between groups, the bruxers group had a higher prevalence of mechanical complications in comparison with the non-bruxers group. CONCLUSIONS This study suggests that bruxism may significantly increase both the implant failure rate and the rate of mechanical and technical complications of implant-supported restorations. Other risk factors may also have influenced the results.
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Affiliation(s)
| | - Jenö Kisch
- Clinic for Prosthodontics, Centre of Dental Specialist Care, Malmö, Sweden
| | - Tomas Albrektsson
- Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö, Sweden.,Department of Biomaterials, Göteborg University, Göteborg, Sweden
| | - Ann Wennerberg
- Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö, Sweden
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Ghadiri M, Nourmohammadi I, Fasihi Ramandi M, Moazen Zadeh E. Association involving serotonin transporter gene linked polymorphic region and bipolar disorder type 1 in Iranian population. Asia Pac Psychiatry 2016; 8:92-7. [PMID: 25808404 DOI: 10.1111/appy.12179] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 02/03/2015] [Indexed: 01/01/2023]
Abstract
INTRODUCTION Serotonin transporter gene linked polymorphic region, also called 5HTTLPR, is a candidate in the genetics of bipolar disorder; however, the results of previous association studies are inconsistent. Several explanations have been proposed for that inconsistency; among them are the existing differences both in the genetic basis of bipolar disorder subtypes and the genetic backgrounds of the studied populations. We aimed to investigate the association of 5HTTLPR with bipolar disorder type I (BP-1) in Iranian population. METHODS In this case-control study, 146 patients with BP-1 and 165 controls were recruited. The patients were selected through the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, 4th edition. It was required that the patients do not have any present history of general medical conditions, substance abuse, and concurrent major psychiatric disorders. The polymorphism was evaluated by blood sampling and subsequent DNA extraction, polymerase chain reaction, and agarose gel electrophoresis. Chi-square test was used for analyzing allelic and genotype frequencies and two-tailed P values were obtained. RESULTS The S allele was significantly more frequent in the BP-1 patients compared with the controls (P = 0.02, S allele odds ratio = 1.5, confidence interval 95% = 1.06-2.11). DISCUSSION Our statistically significant results suggest that the role of 5HTTLPR in the pathogenesis of BP-1 needs to be clarified by further scrutiny in Iranian population and other populations of Near East.
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Affiliation(s)
- Mohammad Ghadiri
- Iran Psychiatric Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Issa Nourmohammadi
- Department of Biochemistry, Iran University of Medical Sciences, Tehran, Iran
| | - Mahdi Fasihi Ramandi
- Research Center of Molecular Biology, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Ehsan Moazen Zadeh
- Mental Health Research Center, Tehran Psychiatric Institute, Iran University of Medical Sciences, Tehran, Iran
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Wang LJ, Lee SY, Chen SL, Chang YH, Chen PS, Huang SY, Tzeng NS, Chen KC, Lee IH, Wang TY, Yang YK, Lu RB. A potential interaction between COMT and MTHFR genetic variants in Han Chinese patients with bipolar II disorder. Sci Rep 2015; 5:8813. [PMID: 25744938 PMCID: PMC4351536 DOI: 10.1038/srep08813] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 12/23/2014] [Indexed: 11/09/2022] Open
Abstract
Bipolar II disorder (BP-II), characterized by recurrent dysregulation of mood, is a serious and chronic psychiatric illness. However, BP-II is commonly under-recognized, even in psychiatric settings. Because dopaminergic disturbance is thought to be involved in the development of bipolar disorder (BPD), it seems essential to investigate dopamine-related genes like the catechol-O-methyltransferase (COMT) gene, which are involved in dopamine metabolism, and the methylenetetrahydrofolate reductase (MTHFR) gene, which may affect COMT methylation and COMT function. The current study examined the association and interaction of the COMT Val158Met and MTHFR C677T variants with BP-II. Nine hundred seventy-eight participants were recruited: 531 with BP-II and 447 healthy controls. The genotypes of the COMT and MTHFR polymorphisms were determined using a polymerase chain reaction-restriction fragment length polymorphism analysis. Logistic regression analysis showed a significant interaction effect of the COMT Val158Met Val/Val genotype and the MTHFR C677T C/T + T/T genotype (P = 0.039) for the protective effect on the odds of developing BP-II. Our findings support preliminary evidence that the COMT and MTHFR genes interact in BP-II, and they imply the connection of both dopaminergic pathways and methylation pathways in the pathogenesis of BP-II.
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Affiliation(s)
- Liang-Jen Wang
- Department of Child and Adolescent Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Sheng-Yu Lee
- Department of Psychiatry, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- Department of Psychiatry, College of Medicine and Hospital, National Cheng Kung University, Tainan, Taiwan
| | - Shiou-Lan Chen
- Department of Psychiatry, College of Medicine and Hospital, National Cheng Kung University, Tainan, Taiwan
- Department of Neurology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yun-Hsuan Chang
- Institute of Allied Health Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Po See Chen
- Department of Psychiatry, College of Medicine and Hospital, National Cheng Kung University, Tainan, Taiwan
| | - San-Yuan Huang
- Department of Psychiatry, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Nian-Sheng Tzeng
- Department of Psychiatry, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Kao Chin Chen
- Department of Psychiatry, College of Medicine and Hospital, National Cheng Kung University, Tainan, Taiwan
| | - I. Hui Lee
- Department of Psychiatry, College of Medicine and Hospital, National Cheng Kung University, Tainan, Taiwan
| | - Tzu-Yun Wang
- Department of Psychiatry, College of Medicine and Hospital, National Cheng Kung University, Tainan, Taiwan
| | - Yen Kuang Yang
- Department of Psychiatry, College of Medicine and Hospital, National Cheng Kung University, Tainan, Taiwan
| | - Ru-Band Lu
- Department of Psychiatry, College of Medicine and Hospital, National Cheng Kung University, Tainan, Taiwan
- Institute of Allied Health Sciences, National Cheng Kung University, Tainan, Taiwan
- Institute of Behavioral Medicine, college of medicine, National Cheng Kung University, Tainan, Taiwan
- Addiction Research Center, National Cheng Kung University, Tainan, Taiwan
- Center for Neuropsychiatric Research, National Health Research Institute, Miaoli, Taiwan
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Dick DM, Agrawal A, Keller MC, Adkins A, Aliev F, Monroe S, Hewitt JK, Kendler KS, Sher KJ. Candidate gene-environment interaction research: reflections and recommendations. Perspect Psychol Sci 2015; 10:37-59. [PMID: 25620996 PMCID: PMC4302784 DOI: 10.1177/1745691614556682] [Citation(s) in RCA: 218] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Studying how genetic predispositions come together with environmental factors to contribute to complex behavioral outcomes has great potential for advancing the understanding of the development of psychopathology. It represents a clear theoretical advance over studying these factors in isolation. However, research at the intersection of multiple fields creates many challenges. We review several reasons why the rapidly expanding candidate gene-environment interaction (cG×E) literature should be considered with a degree of caution. We discuss lessons learned about candidate gene main effects from the evolving genetics literature and how these inform the study of cG×E. We review the importance of the measurement of the gene and environment of interest in cG×E studies. We discuss statistical concerns with modeling cG×E that are frequently overlooked. Furthermore, we review other challenges that have likely contributed to the cG×E literature being difficult to interpret, including low power and publication bias. Many of these issues are similar to other concerns about research integrity (e.g., high false-positive rates) that have received increasing attention in the social sciences. We provide recommendations for rigorous research practices for cG×E studies that we believe will advance its potential to contribute more robustly to the understanding of complex behavioral phenotypes.
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Affiliation(s)
| | - Arpana Agrawal
- Department of Psychiatry, Washington University in St. Louis
| | - Matthew C Keller
- Institute for Behavioral Genetics, University of Colorado Boulder
| | - Amy Adkins
- Department of Psychiatry, Virginia Commonwealth University
| | - Fazil Aliev
- Department of Psychiatry, Virginia Commonwealth University
| | - Scott Monroe
- Department of Psychology, University of Notre Dame
| | - John K Hewitt
- Department of Psychiatry, Washington University in St. Louis
| | | | - Kenneth J Sher
- Department of Psychological Sciences, University of Missouri
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Hess JL, Glatt SJ. How might ZNF804A variants influence risk for schizophrenia and bipolar disorder? A literature review, synthesis, and bioinformatic analysis. Am J Med Genet B Neuropsychiatr Genet 2014; 165B:28-40. [PMID: 24123948 DOI: 10.1002/ajmg.b.32207] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 09/12/2013] [Indexed: 01/16/2023]
Abstract
The gene that encodes zinc finger protein 804A (ZNF804A) became a candidate risk gene for schizophrenia (SZ) after surpassing genome-wide significance thresholds in replicated genome-wide association scans and meta-analyses. Much remains unknown about this reported gene expression regulator; however, preliminary work has yielded insights into functional and biological effects of ZNF804A by targeting its regulatory activities in vitro and by characterizing allele-specific interactions with its risk-conferring single nucleotide polymorphisms (SNPs). There is now strong epidemiologic evidence for a role of ZNF804A polymorphisms in both SZ and bipolar disorder (BD); however, functional links between implicated variants and susceptible biological states have not been solidified. Here we briefly review the genetic evidence implicating ZNF804A polymorphisms as genetic risk factors for both SZ and BD, and discuss the potential functional consequences of these variants on the regulation of ZNF804A and its downstream targets. Empirical work and predictive bioinformatic analyses of the alternate alleles of the two most strongly implicated ZNF804A polymorphisms suggest they might alter the affinity of the gene sequence for DNA- and/or RNA-binding proteins, which might in turn alter expression levels of the gene or particular ZNF804A isoforms. Future work should focus on clarifying the critical periods and cofactors regulating these genetic influences on ZNF804A expression, as well as the downstream biological consequences of an imbalance in the expression of ZNF804A and its various mRNA isoforms.
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Affiliation(s)
- Jonathan L Hess
- Psychiatric Genetic Epidemiology & Neurobiology Laboratory (PsychGENe Lab), Departments of Psychiatry and Behavioral Sciences and Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, New York
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Kanazawa T, Ikeda M, Glatt SJ, Tsutsumi A, Kikuyama H, Kawamura Y, Nishida N, Miyagawa T, Hashimoto R, Takeda M, Sasaki T, Tokunaga K, Koh J, Iwata N, Yoneda H. Genome-wide association study of atypical psychosis. Am J Med Genet B Neuropsychiatr Genet 2013; 162B:679-86. [PMID: 24132900 DOI: 10.1002/ajmg.b.32164] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 03/20/2013] [Indexed: 01/22/2023]
Abstract
Atypical psychosis with a periodic course of exacerbation and features of major psychiatric disorders [schizophrenia (SZ) and bipolar disorder (BD)] has a long history in clinical psychiatry in Japan. Based upon the new criteria of atypical psychosis, a Genome-Wide Association Study (GWAS) was conducted to identify the risk gene or variants. The relationships between atypical psychosis, SZ and BD were then assessed using independent GWAS data. Forty-seven patients with solid criteria of atypical psychosis and 882 normal controls (NCs) were scanned using an Affymetrics 6.0 chip. GWAS SZ data (560 SZ cases and 548 NCs) and GWAS BD (107 cases with BD type 1 and 107 NCs) were compared using gene-based analysis. The most significant SNPs were detected around the CHN2/CPVL genes (rs245914, P = 1.6 × 10(-7)) , COL21A1 gene (rs12196860, P = 2.45 × 10(-7) ), and PYGL/TRIM9 genes (rs1959536, P = 7.73 × 10(-7) ), although none of the single-nucleotide polymorphisms exhibited genome-wide significance (P = 5 × 10(-8) ). One of the highest peaks was detected on the major histocompatibility complex region, where large SZ GWASs have previously disclosed an association. The gene-based analysis suggested significant enrichment between SZ and atypical psychosis (P = 0.01), but not BD. This study provides clues about the types of patient whose diagnosis lies between SZ and BD. Studies with larger samples are required to determine the causal variant.
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Affiliation(s)
- Tetsufumi Kanazawa
- Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan; Department of Psychiatry, School of Medicine, Fujita Health University, Toyoake, Aichi, Japan
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Hukic DS, Frisén L, Backlund L, Lavebratt C, Landén M, Träskman-Bendz L, Edman G, Schalling M, Ösby U. Cognitive manic symptoms in bipolar disorder associated with polymorphisms in the DAOA and COMT genes. PLoS One 2013; 8:e67450. [PMID: 23861766 PMCID: PMC3702534 DOI: 10.1371/journal.pone.0067450] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 05/17/2013] [Indexed: 12/20/2022] Open
Abstract
INTRODUCTION Bipolar disorder is characterized by severe mood symptoms including major depressive and manic episodes. During manic episodes, many patients show cognitive dysfunction. Dopamine and glutamate are important for cognitive processing, thus the COMT and DAOA genes that modulate the expression of these neurotransmitters are of interest for studies of cognitive function. METHODOLOGY Focusing on the most severe episode of mania, a factor was found with the combined symptoms of talkativeness, distractibility, and thought disorder, considered a cognitive manic symptoms (CMS) factor. 488 patients were genotyped, out of which 373 (76%) had talkativeness, 269 (55%) distractibility, and 372 (76%) thought disorder. 215 (44%) patients were positive for all three symptoms, thus showing CMS (Table 1). As population controls, 1,044 anonymous blood donors (ABD) were used. Case-case and case-control design models were used to investigate genetic associations between cognitive manic symptoms in bipolar 1 disorder and SNPs in the COMT and DAOA genes. [Table: see text]. RESULTS The finding of this study was that cognitive manic symptoms in patients with bipolar 1 disorder was associated with genetic variants in the DAOA and COMT genes. Nominal association for DAOA SNPs and COMT SNPs to cognitive symptoms factor in bipolar 1 disorder was found in both allelic (Table 2) and haplotypic (Table 3) analyses. Genotypic association analyses also supported our findings. However, only one association, when CMS patients were compared to ABD controls, survived correction for multiple testing by max (T) permutation. Data also suggested interaction between SNPs rs2391191 in DAOA and rs5993883 in COMT in the case-control model. [Table: see text] [Table: see text]. CONCLUSION Identifying genes associated with cognitive functioning has clinical implications for assessment of prognosis and progression. Our finding are consistent with other studies showing genetic associations between the COMT and DAOA genes and impaired cognition both in psychiatric disorders and in the general population.
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Affiliation(s)
- Dzana Sudic Hukic
- Neurogenetics Unit, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
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Jiang HY, Qiao F, Xu XF, Yang Y, Bai Y, Jiang LL. Meta-analysis confirms a functional polymorphism (5-HTTLPR) in the serotonin transporter gene conferring risk of bipolar disorder in European populations. Neurosci Lett 2013; 549:191-6. [PMID: 23756178 DOI: 10.1016/j.neulet.2013.05.065] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 05/24/2013] [Accepted: 05/31/2013] [Indexed: 12/21/2022]
Abstract
The serotonin transporter (5-HTT) is a candidate risk gene for bipolar disorder, and a functional polymorphism of 44-bp insertion/deletion (5-HTTLPR) located in the promoter region of this gene has been investigated for the association with the illness extensively among worldwide populations, but overall results were inconsistent and its role in the disorder remains unclear. The present study attempts to find its potential association with bipolar disorder using meta-analyzes that maximize the statistical power. We applied meta-analysis techniques by combining all available case-control studies of 5-HTTLPR and bipolar disorder in samples of European ancestry (with a total of 3778 cases and 4997 controls), and we assessed the evidence for allelic associations, heterogeneity among different studies, influence of each single study, and potential publication bias. The short allele (S allele) of 5-HTTLPR showed a significant association with bipolar disorder in our meta-analysis (odds ratio=1.10, p-value=0.005), suggesting it is likely a risk polymorphism for the illness, and the observed OR is consistent with other susceptibility loci identified through recent large-scale genetic association studies on bipolar disorder, which could be regarded simply as a small but detectable effects.
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Affiliation(s)
- Hong-Yan Jiang
- Department of Psychiatry, The First Affiliated Hospital of Kunming Medical University, Kunming, China.
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Abstract
INTRODUCTION Bipolar Disorder (BD) is a serious mood disorder, the aetiology of which is still unclear. The disorder is characterised by extreme mood variability in which patients fluctuate between markedly euphoric, irritable, and elevated states to periods of severe depression. The current research literature shows that BD patients demonstrate compromised neurocognitive ability in addition to these mood symptoms. Viable candidate genes implicated in neurocognitive and socioemotional processes may explain the development of these core emotion abnormalities. Additionally, links between faulty neurocognition and impaired socioemotional ability complement genetic explanations of BD pathogenesis. This review examines associations between cognition indexing prefrontal neural regions and socioemotional impairments including emotion processing and regulation. A review of the effect of COMT and TPH2 on these functions is also explored. METHODS Major computer databases including PsycINFO, Google Scholar, and Medline were consulted in order to conduct a comprehensive review of the genetic and cognitive literature in BD. RESULTS This review determines that COMT and TPH2 genetic variants contribute susceptibility to abnormal prefrontal neurocognitive function which oversees the processing and regulation of emotion. This provides for greater understanding of some of the emotional and cognitive symptoms in BD. CONCLUSIONS Current findings in this direction show promise, although the literature is still in its infancy and further empirical research is required to investigate these links explicitly.
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Affiliation(s)
- Tamsyn E Van Rheenen
- Brain and Psychological Sciences Research Centre, Faculty of Life and Social Sciences, Swinburne University, and Cognitive Neuropsychology Laboratory, Monash Alfred Psychiatry Research Center, The Alfred Hospital, Melbourne, Australia.
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Xu X, Breen G, Luo L, Sun B, Chen CK, Paredes UM, Huang YS, Wu YY, Asherson P. Investigation of the ZNF804A gene polymorphism with genetic risk for bipolar disorder in attention deficit hyperactivity disorder. BMC Res Notes 2013; 6:29. [PMID: 23351715 PMCID: PMC3571974 DOI: 10.1186/1756-0500-6-29] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 01/23/2013] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Genome-wide association studies (GWAS) have been conducted on many psychiatric disorders. Evidence from large GWAS indicates that the single nucleotide polymorphism (SNP) rs1344706 in the zinc-finger protein 804A gene (ZNF804A) is associated with psychotic disorders including bipolar disorder and schizophrenia. One study also found significant association between rs1344706 and the executive control network of attention. In this study we examine the role of the rs1344706 polymorphism that previously showed association with BD and is known to alter expression of the gene in two clinical family-based ADHD samples from the UK and Taiwan. FINDINGS To investigate the association between rs1344706 and ADHD, two family samples of ADHD probands from the United Kingdom (n = 180) and Taiwan (n = 212) were genotyped using TaqMan SNP genotyping assays and analysed using within-family transmission disequilibrium test. No significant associations were found between rs1344706 polymorphism and ADHD in either of the samples from Taiwan (P = 0.91) and UK (P = 0.41). Even combining the two datasets together the A allele of rs1344706 SNP was still not significantly over-transmitted to affected probands (P = 0.50). Furthermore, there was no evidence of association with the specific symptoms subgroups of inattention or hyperactivity-impulsivity. CONCLUSIONS In this study we used family-based ADHD data in the UK and Taiwanese population to test for an association between rs1344706 SNP in the ZNF804A gene and ADHD. Results showed no significant association of rs1344706 with ADHD in UK and Taiwanese samples.
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Affiliation(s)
- Xiaohui Xu
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, UK.
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Lee SY, Chen SL, Wang YS, Chang YH, Huang SY, Tzeng NS, Lee IH, Yeh TL, Yang YK, Lu RB. COMT and BDNF interacted in bipolar II disorder not comorbid with anxiety disorder. Behav Brain Res 2012; 237:243-8. [PMID: 23026378 DOI: 10.1016/j.bbr.2012.09.039] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 09/18/2012] [Accepted: 09/20/2012] [Indexed: 12/14/2022]
Abstract
Bipolar disorder (BP), especially bipolar II disorder (BP-II), is highly comorbid with anxiety disorder (AD). Monoaminergic dysfunction has been implicated in the pathogenesis of BP, it may be important to investigate genes such as the catechol-O-methyltransferase (COMT), involved in monoamine metabolism and brain-derived neurotrophic factor (BDNF) genes, modulating the monoamine system. We therefore examined the association of the COMT Val158Met and BDNF Val66Met polymorphisms with BP-II with and without comorbidity of AD, and possible interactions between these genes. Seven hundred and seventy-one participants were recruited: 314 with bipolar-II without AD, 117 with bipolar-II with AD, and 340 healthy controls. The genotypes of the COMT and BDNF polymorphisms were determined using polymerase chain reactions plus restriction fragment length polymorphism analysis. Logistic regression analysis showed a significant effect of the COMT and the BDNF polymorphisms, and a significant interaction effect for the Val/Val genotypes of the BDNF Val66Met polymorphism and the COMsT Val158Met Val/Met and Met/Met genotypes (P=0.007, 0.048) discriminated between BP-II without AD patients and controls. Our findings provide initial evidence that the COMT and BDNF genes interact in bipolar-II without AD. Our findings suggest the involvement of dopaminergic pathway in the pathogenesis of bipolar-II.
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Affiliation(s)
- Sheng-Yu Lee
- Department of Psychiatry, National Cheng Kung University, Tainan, Taiwan
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Goel N, Banks S, Lin L, Mignot E, Dinges DF. Catechol-O-methyltransferase Val158Met polymorphism associates with individual differences in sleep physiologic responses to chronic sleep loss. PLoS One 2011; 6:e29283. [PMID: 22216231 PMCID: PMC3246458 DOI: 10.1371/journal.pone.0029283] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 11/23/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The COMT Val158Met polymorphism modulates cortical dopaminergic catabolism, and predicts individual differences in prefrontal executive functioning in healthy adults and schizophrenic patients, and associates with EEG differences during sleep loss. We assessed whether the COMT Val158Met polymorphism was a novel marker in healthy adults of differential vulnerability to chronic partial sleep deprivation (PSD), a condition distinct from total sleep loss and one experienced by millions on a daily and persistent basis. METHODOLOGY/PRINCIPAL FINDINGS 20 Met/Met, 64 Val/Met, and 45 Val/Val subjects participated in a protocol of two baseline 10h time in bed (TIB) nights followed by five consecutive 4 h TIB nights. Met/Met subjects showed differentially steeper declines in non-REM EEG slow-wave energy (SWE)-the putative homeostatic marker of sleep drive-during PSD, despite comparable baseline SWE declines. Val/Val subjects showed differentially smaller increases in slow-wave sleep and smaller reductions in stage 2 sleep during PSD, and had more stage 1 sleep across nights and a shorter baseline REM sleep latency. The genotypes, however, did not differ in performance across various executive function and cognitive tasks and showed comparable increases in subjective and physiological sleepiness in response to chronic sleep loss. Met/Met genotypic and Met allelic frequencies were higher in whites than African Americans. CONCLUSIONS/SIGNIFICANCE The COMT Val158Met polymorphism may be a genetic biomarker for predicting individual differences in sleep physiology-but not in cognitive and executive functioning-resulting from sleep loss in a healthy, racially-diverse adult population of men and women. Beyond healthy sleepers, our results may also provide insight for predicting sleep loss responses in patients with schizophrenia and other psychiatric disorders, since these groups repeatedly experience chronically-curtailed sleep and demonstrate COMT-related treatment responses and risk factors for symptom exacerbation.
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Affiliation(s)
- Namni Goel
- Division of Sleep and Chronobiology, Department of Psychiatry, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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Shaikh M, Hall MH, Schulze K, Dutt A, Walshe M, Williams I, Constante M, Picchioni M, Toulopoulou T, Collier D, Rijsdijk F, Powell J, Arranz M, Murray RM, Bramon E. Do COMT, BDNF and NRG1 polymorphisms influence P50 sensory gating in psychosis? Psychol Med 2011; 41:263-276. [PMID: 20102668 DOI: 10.1017/s003329170999239x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Auditory P50 sensory gating deficits correlate with genetic risk for schizophrenia and constitute a plausible endophenotype for the disease. The well-supported role of catechol-O-methyltransferase (COMT), brain-derived neurotrophic factor (BDNF) and neuregulin 1 (NRG1) genes in neurodevelopment and cognition make a strong theoretical case for their influence on the P50 endophenotype. METHOD The possible role of NRG1, COMT Val158Met and BDNF Val66Met gene polymorphisms on the P50 endophenotype was examined in a large sample consisting of psychotic patients, their unaffected relatives and unrelated healthy controls using linear regression analyses. RESULTS Although P50 deficits were present in patients and their unaffected relatives, there was no evidence for an association between NRG1, COMT Val158Met or BDNF Val66Met genotypes and the P50 endophenotype. CONCLUSIONS The evidence from our large study suggests that any such association between P50 indices and NRG1, COMT Val158Met or BDNF Val66Met genotypes, if present, must be very subtle.
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Affiliation(s)
- M Shaikh
- NIHR Biomedical Research Centre, Institute of Psychiatry, King's College London/South London and Maudsley NHS Foundation Trust, London, UK.
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Fan M, Liu B, Jiang T, Jiang X, Zhao H, Zhang J. Meta-analysis of the association between the monoamine oxidase-A gene and mood disorders. Psychiatr Genet 2010; 20:1-7. [DOI: 10.1097/ypg.0b013e3283351112] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lee HY, Kim YK. Catechol-O-methyltransferase Val158Met polymorphism affects therapeutic response to mood stabilizer in symptomatic manic patients. Psychiatry Res 2010; 175:63-6. [PMID: 20004480 DOI: 10.1016/j.psychres.2008.09.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2008] [Revised: 07/19/2008] [Accepted: 09/30/2008] [Indexed: 10/20/2022]
Abstract
Catechol-O-methyltransferase (COMT) is a candidate gene for the pathogenesis of some psychiatric disorders. The aim of this study is to examine the role of the COMT gene Val158Met polymorphism on the clinical aspects of bipolar disorder including symptomatology and therapeutic response. This study comprised 144 unrelated manic patients who met strict DSM-IV criteria for bipolar I disorder and 157 healthy unrelated controls. All subjects were of Korean ethnicity. To evaluate the clinical symptoms, we used the Young Mania Rating Scale at baseline and 6 weeks after treatment. No statistically significant difference in genotype distribution was found between manic patients and normal controls. There was also no significant difference in symptomatology among the genotypes in manic patients. In therapeutic response, however, patients with the Met/Met genotype were significantly more frequent in the non-responder than in the responder group. Our results suggest that the COMT gene polymorphism in the therapeutic response to mood stabilizers in manic patients. Further studies with a larger number of subjects and well-controlled design will be required to better understand the role of the COMT gene polymorphism on the therapeutic response to mood stabilizer in manic patients.
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Affiliation(s)
- Hwa-Young Lee
- Department of Psychiatry, College of Medicine, Korea University, Seoul, Republic of Korea
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25
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Bousman CA, Glatt SJ, Everall IP, Tsuang MT. Genetic association studies of methamphetamine use disorders: A systematic review and synthesis. Am J Med Genet B Neuropsychiatr Genet 2009; 150B:1025-49. [PMID: 19219857 DOI: 10.1002/ajmg.b.30936] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Efforts to understand the biological processes that increase susceptibility to methamphetamine (METH) use disorders (i.e., abuse, dependence, and psychosis) have uncovered several putative genotypic variants. However, to date a synthesis of this information has not been conducted. Thus, systematic searches of the current literature were undertaken for genetic-association studies of METH use disorders. Each gene's chromosomal location, function, and examined polymorphic markers were extracted. Frequencies, odds ratios and 95% confidence intervals for risk alleles, as well as sample size and power, were calculated. We uncovered 38 studies examining 39 genes, of which 18 were found to have a significant genotypic, allelic, and/or haplotypic association with METH use disorders. Three genes (COMT, DRD4, and GABRA1) were associated with METH abuse, nine (ARRB2, BDNF, CYP2D6, GLYT1, GSTM1, GSTP1, PDYN, PICK1, and SLC22A3) with METH dependence, two (AKT1 and GABRG2) with METH abuse/dependence, and four (DTNBP1, OPRM1, SNCA, and SOD2) with METH psychosis. Limitations related to phenotypic classification, statistical power, and potential publication bias in the current literature were noted. Similar to other behavioral, psychiatric, and substance use disorders, the genetic epidemiology of METH use disorders is complex and likely polygenic. National and international collaborative efforts are needed to increase the availability of large population-based samples and improve upon the power to detect genetic associations of small magnitude. Further, replication of the findings reviewed here along with further development of more rigorous methodologies and reporting protocols will aid in delineating the complex genetic epidemiology of METH use disorders.
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Affiliation(s)
- Chad A Bousman
- Department of Psychiatry, Center for Behavioral Genomics, University of California San Diego, La Jolla, 92037, USA
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Abstract
OBJECTIVE Despite effective pharmacological treatments for bipolar disorder, we still lack a comprehensive pathophysiological model of the illness. Recent neurobiological research has implicated a number of key brain regions and neuronal components in the behavioural and cognitive manifestations of bipolar disorder. Dopamine has previously been investigated in some depth in bipolar disorder, but of late has not been a primary focus of attention. This article examines the role of dopamine in bipolar disorder, incorporating recent advances into established models where possible. METHODS A critical evaluation of the literature was undertaken, including a review of behavioural, neurochemical, receptor, and imaging studies, as well as genetic studies focusing on dopamine receptors and related metabolic pathways. In addition, pharmacologic manipulation of the central dopaminergic pathways and comparisons with other disease states such as schizophrenia were considered, principally as a means of exploring the hypothesised models. RESULTS Multiple lines of evidence, including data from pharmacological interventions and structural and functional magnetic resonance imaging studies, suggest that the dopaminergic system may play a central role in bipolar disorder. CONCLUSION Future research into the pathophysiological mechanisms of bipolar disorder and the development of new treatments for bipolar disorder should focus on the dopaminergic system.
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Affiliation(s)
- David A Cousins
- Newcastle Magnetic Resonance Centre, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.
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Zhang Z, Lindpaintner K, Che R, He Z, Wang P, Yang P, Feng G, He L, Shi Y. The Val/Met functional polymorphism in COMT confers susceptibility to bipolar disorder: evidence from an association study and a meta-analysis. J Neural Transm (Vienna) 2009; 116:1193-200. [DOI: 10.1007/s00702-009-0260-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Accepted: 06/18/2009] [Indexed: 01/14/2023]
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Abstract
The risk of bipolar disorder (BPD) (15-42%) in first-degree relatives of children with BPD are consistently larger than the 8.7% estimate of recurrence risk of BPD in first-degree relatives of adult BPD cases. There have been no family linkage studies of pediatric BPD, but secondary analyses of adult linkage samples suggest that early-onset BPD both increases the strength of associations in linkage studies. Positive associations with pediatric BPD and the BDNF gene (Vall66), the GAD1 gene (4s2241165), and the dopamine transporter gene (rs41084) have been reported but none of these associations have been replicated in independent samples. The number of informative families examined so far is quite small and studies were vastly underpowered to detect small effects. An adequately powered sample will likely require collaborative ascertainment of cases and families from multiple sites using valid and accepted measures of pediatric BPD.
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Affiliation(s)
- Eric Mick
- Departments of Psychiatry, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, USA.
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Craddock N, Sklar P. Genetics of bipolar disorder: successful start to a long journey. Trends Genet 2009; 25:99-105. [PMID: 19144440 DOI: 10.1016/j.tig.2008.12.002] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2008] [Revised: 12/01/2008] [Accepted: 12/01/2008] [Indexed: 11/25/2022]
Abstract
Family and twin studies attest to the importance of genetic factors influencing susceptibility to bipolar disorder and to its genetic and phenotypic complexity. Although linkage and candidate gene association studies have repeatedly implicated some chromosome regions and certain genes, they have not produced the level of unambiguous support required to confirm the involvement of any specific gene or sequence variant in the pathogenesis of bipolar disorder. However, strong associations have recently been reported in meta-analyses of genome-wide association studies and the systematic study of structural variation is ongoing. These findings indicate that the study of large, phenotypically well-characterized samples will make an important contribution to delineating the etiology and pathogenesis of bipolar disorder and thereby pave the way for major improvements in clinical management.
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Affiliation(s)
- Nick Craddock
- Department of Psychological Medicine, Henry Wellcome Building, School of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, UK.
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Shi J, Badner JA, Hattori E, Potash JB, Willour VL, McMahon FJ, Gershon ES, Liu C. Neurotransmission and bipolar disorder: a systematic family-based association study. Am J Med Genet B Neuropsychiatr Genet 2008; 147B:1270-7. [PMID: 18444252 PMCID: PMC2574701 DOI: 10.1002/ajmg.b.30769] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neurotransmission pathways/systems have been proposed to be involved in the pathophysiology and treatment of bipolar disorder for over 40 years. In order to test the hypothesis that common variants of genes in one or more of five neurotransmission systems confer risk for bipolar disorder, we analyzed 1,005 tag single nucleotide polymorphisms in 90 genes from dopaminergic, serotonergic, noradrenergic, GABAergic, and glutamatergic neurotransmitter systems in 101 trios and 203 quads from Caucasian bipolar families. Our sample has 80% power to detect ORs >or= 1.82 and >or=1.57 for minor allele frequencies of 0.1 and 0.5, respectively. Nominally significant allelic and haplotypic associations were found for genes from each neurotransmission system, with several reaching gene-wide significance (allelic: GRIA1, GRIN2D, and QDPR; haplotypic: GRIN2C, QDPR, and SLC6A3). However, none of these associations survived correction for multiple testing in an individual system, or in all systems considered together. Significant single nucleotide polymorphism associations were not found with sub-phenotypes (alcoholism, psychosis, substance abuse, and suicide attempts) or significant gene-gene interactions. These results suggest that, within the detectable odds ratios of this study, common variants of the selected genes in the five neurotransmission systems do not play major roles in influencing the risk for bipolar disorder or comorbid sub-phenotypes.
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Affiliation(s)
- Jiajun Shi
- Department of Psychiatry, University of Chicago, Chicago, Illinois 60637, USA.
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Gardner M, Bertranpetit J, Comas D. Worldwide genetic variation in dopamine and serotonin pathway genes: implications for association studies. Am J Med Genet B Neuropsychiatr Genet 2008; 147B:1070-5. [PMID: 18270970 DOI: 10.1002/ajmg.b.30717] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The dopamine and serotonin systems are two of the most important neurotransmitter pathways in the human nervous system and their roles in controlling behavior and mental status are well accepted. Genes from both systems have been widely implicated in psychiatric and behavioral disorders, with numerous reports of associations and almost equally as numerous reports of the failure to replicate a previous finding of association. We investigate a set of 21 dopamine and serotonin genes commonly tested for association with psychiatric disease in a set of 39 worldwide populations representing global genetic diversity to see whether the failure to replicate findings of association may be explained by population based differences in allele frequencies and linkage disequilibrium (LD) in this gene set. We present results demonstrating a surprising homogeneity of the allele frequencies across worldwide populations in these genes. LD both for populations within continent groupings and across continental regions also showed a remarkable similarity. These findings taken together suggest that ethnic differences in these parameters are not major generators of artifacts in genetic association studies of psychiatric disorders with genes from this set. Therefore, factors other than ethnic differences in genetic variation may explain the discrepancies reported among genetic association studies with this set of genes to date. The transferability of tagSNPs defined in the HapMap populations to other worldwide populations was also investigated and found to be high. A list of tagSNPs per gene and continental region is proposed providing a guide for future association studies with these genes.
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Affiliation(s)
- Michelle Gardner
- Unitat de Biologia Evolutiva, Universitat Pompeu Fabra, Doctor Aiguader, Barcelona, Spain
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Abstract
Parkinson's disease (PD) is a neurological disorder characterized by the degeneration of dopaminergic neurons, with consequent reduction in striatal dopamine levels leading to characteristic motor symptoms. The most effective treatment for this disease continues to be the dopamine replacement therapy with levodopa together with an inhibitor of aromatic amino acid decarboxylase (AADC). The efficacy of this therapy, however, decreases with time and most patients develop fluctuating responses and dyskinesias. The last decade showed that the use of catechol-O-methyltransferase inhibitors as adjuvants to the levodopa/AADC inhibitor therapy, significantly improves the clinical benefits of this therapy. The purpose of this article is to review the current knowledge on the enzyme catechol-O-methyltransferase (COMT) and the role of COMT inhibitors in PD as a new therapeutic approach to PD involving conversion of levodopa to dopamine at the target region in the brain and facilitation of the continuous action of this amine at the receptor sites. A historical overview of the discovery and development of COMT inhibitors is presented with a special emphasis on nebicapone, presently under clinical development, as well as entacapone and tolcapone, which are already approved as adjuncts in the therapy of PD. This article reviews human pharmacokinetic and pharmacodynamic properties of these drugs as well as their clinical efficacy and safety.
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Affiliation(s)
- Maria João Bonifácio
- Department of Research and Development, BIAL (Portela & Co S.A.), S Mamede do Coronado, Portugal
| | - P. Nuno Palma
- Department of Research and Development, BIAL (Portela & Co S.A.), S Mamede do Coronado, Portugal
| | - Luís Almeida
- Department of Research and Development, BIAL (Portela & Co S.A.), S Mamede do Coronado, Portugal
- Institute of Pharmacology and Therapeutics, Faculty of Medicine, Porto, Portugal
| | - Patrício Soares‐da‐Silva
- Department of Research and Development, BIAL (Portela & Co S.A.), S Mamede do Coronado, Portugal
- Institute of Pharmacology and Therapeutics, Faculty of Medicine, Porto, Portugal
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Cao MQ, Hu SY, Zhang CH, Xia DS. Study on the interrelationship between 5-HTTLPR/G-protein beta3 subunit (C825T) polymorphisms and depressive disorder. Psychiatr Genet 2007; 17:233-8. [PMID: 17621167 DOI: 10.1097/ypg.0b013e3280c1e5de] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess whether the promoter region of the serotonin transporter gene (5-HTTLPR) and G-protein beta3-subunit (GNbeta3 C825T) polymorphisms are associated with depressive disorder and explore the genetic mechanism concerning the pathogenesis of this disorder. METHODS The genotypes were determined with polymerase chain reaction and allele-specific restriction enzyme analysis. Patients suffering from depression (n=184) and sex and age-matched controls (n=158) were compared in this study. RESULTS The frequencies of 5-HTTLPR SS and GNbeta3 825TT genotypes and 5-HTTLPR S and GNbeta3 825T alleles in patients suffering from depression were significantly higher than those in the controls (P<0.01). Combined genotype analysis showed that individuals with both 5-HTTLPR S and GNbeta3 825T alleles (odds ratio=3.25, P=0.002) had a risk of depressive disorder higher than those with 5-HTTLPR S (odds ratio=1.817, P=0.01) or GNbeta3 825T alleles (odds ratio=2.214, P=0.001) alone. CONCLUSIONS These results indicated that the etiology of depressive disorder is associated with 5-HTTLPR and GNbeta3 C825T polymorphisms. Our data also suggests that an interaction effect may exist between the 5-HTTLPR S allele and GNbeta3 825T allele in increasing the risk of depressive disorder.
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Affiliation(s)
- Mei-Qun Cao
- Research Institute of Integrated Traditional Chinese and Western Medicine, Xiang Ya Hospital, Central South University, Changsha, Hunan, Republic of China.
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Kempisty B, Sikora J, Lianeri M, Szczepankiewicz A, Czerski P, Hauser J, Jagodzinski PP. MTHFD 1958G>A and MTR 2756A>G polymorphisms are associated with bipolar disorder and schizophrenia. Psychiatr Genet 2007; 17:177-81. [PMID: 17417062 DOI: 10.1097/ypg.0b013e328029826f] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND The etiology of bipolar disorder (BD) and schizophrenia is very complex. Polymorphic variants of genes encoding enzymes of the monoaminergic may be involved in development of BD and schizophrenia. Therefore, we examined the prevalence of 1958G>A polymorphism of MTHFD1 gene, encoding trifunctional folate enzyme 5,10-methylenetetrahydrofolate dehydrogenase, 5,10-methenyltetrahydrofolate cyclohydrolase and 10-formyltetrahydrofolate synthetase (MTHFD1), and 2756A>G variant of methionine synthase (MTR) gene in patients with BD (n=200), schizophrenia (n=200) and in controls (n=300). OBJECTIVE We investigated the genotypic and allelic frequencies of MTHFD1 1958G>A (R653Q) and MTR 2756A>G (D919G) gene polymorphisms in a group of bipolar (n=200) and schizophrenic patients (n=200), as well as in controls (n=300). METHODS The distributon of genotypes in all groups was tested for deviation from Hardy-Weinberg equilibrium (HWE). The Pearson's chi-square (chi) test and Fisher's exact test were applied to assess differences in the genotypic and allelic (respectively) distribution between groups of patients and controls. MAIN RESULTS We found that MTHFD1 1958AA or 1958AG genotypes constitute risk factors for development of bipolar disorder type I (BDI) or schizophrenia with odds ratios (OR)=1.743 (95% CI=1.211-2.508; P=0.0027; P (corr)=0.0054) and 2.667 (95% CI=1.845-3.854; P=0.0001; P (corr)=0.0002), respectively. In the same groups, the MTR 2756GG or 2756AG genotypes also constitute significant risk factors in occurrence of BDI and schizophrenia with OR=1.621 (95% CI=1.130-2.326; P=0.0086; P (corr)=0.0172) and 1.556 (95% CI=1.085-2.232; P=0.0160; P (corr)=0.032), respectively. Gender classification of patients indicated significant association only of MTHFD1 1958A allele with BDI and schizophrenia in the male patients OR=1.838 (95% CI=1.114-3.031; P=0.0166; P (corr)=0.0332) and OR=3.964 (95% CI=2.358-6.663; P=0.0001 P (corr)=0.0002), respectively. CONCLUSION Since MTHFD and MTR genes are located in 14q24 and 1q43 loci, our findings support the significance of chromosomes 14q and 1q in etiopathogenesis of bipolar disorder and schizophrenia.
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Affiliation(s)
- Bartosz Kempisty
- Department of Biochemistry and Molecular Biology, Poznan University of Medical Sciences, Poznan, Poland
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35
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Abstract
The major findings regarding the genetics of stress response and stress-related disorders are: (i) variations in genes involved in the sympathetic system or in the hypothalamic-pituitary-adrenocortical axis are associated with altered stress responses; (ii) genes related to the renin-angiotensin-aldosterone system or inflammation/immune response show associations with cardiovascular disorders; (iii) genes involved in monoaminergic neurotransmitter systems are associated with bipolar disorder and unipolar depression. The vast majority of these association studies followed a conventional hypothesis-driven approach, restricting the gene selection to established candidates. This very conservative approach retarded our understanding of the complex interplay between genetic factors, stress response, and stress-related disorders. Chip-based whole-genome technologies will open up access to new unbiased and statistically efficient approaches that will help to identify new candidate genes, which should be thoroughly validated in clinical and preclinical confirmatory studies. This, together with the use of new text- and information-mining tools, will bring us closer to integrating all the findings into sophisticated models delineating the pathways from genes to stress response and stress-related disorders.
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Affiliation(s)
- Marcus Ising
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, D-80804 Munich, Germany.
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36
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Van Den Bogaert A, Sleegers K, De Zutter S, Heyrman L, Norrback KF, Adolfsson R, Van Broeckhoven C, Del-Favero J. No allelic association or interaction of three known functional polymorphisms with bipolar disorder in a northern Swedish isolated population. Psychiatr Genet 2006; 16:209-12. [PMID: 16969276 DOI: 10.1097/01.ypg.0000218623.03752.e4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Most genetic association studies in bipolar disorder have focussed on genes involved in major neurotransmitter systems or brain development. Functional polymorphisms in the serotonin transporter (5-HTTLPR), catechol-O-methyltransferase (Val158Met) and dopamine D3 receptor (Ser9Gly) genes have all been associated with bipolar disorder. We aimed at investigating whether these functional variants contribute to the genetic etiology of bipolar disorder in a northern Swedish isolated population. Moreover, we wanted to gain information about the synergistic contribution of these functional variants. Neither of these functional polymorphisms was associated with bipolar disorder in the northern Swedish patient-control sample nor did we find evidence of gene-gene interaction. Together, our data suggest that these functional variants are not involved in the etiology of bipolar disorder in the northern Swedish population nor did gene-gene interaction analysis support a central role of these variants in bipolar disorder.
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Affiliation(s)
- Ann Van Den Bogaert
- Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology, Antwerp, Belgium
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37
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Abstract
The enormous public health importance of mood disorders, when considered alongside their substantial heritabilities, has stimulated much work, predominantly in bipolar disorder but increasingly in unipolar depression, aimed at identifying susceptibility genes using both positional and functional molecular genetic approaches. Several regions of interest have emerged in linkage studies and, recently, evidence implicating specific genes has been reported; the best supported include BDNF and DAOA but further replications are required and phenotypic relationships and biological mechanisms need investigation. The complexity of psychiatric phenotypes is demonstrated by (a) the evidence accumulating for an overlap in genetic susceptibility across the traditional classification systems that divide disorders into schizophrenia and mood disorders, and (b) evidence suggestive of gene-environment interactions.
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Affiliation(s)
- Nick Craddock
- Department of Psychological Medicine, The Henry Wellcome Building for Biomedical Research in Wales, Wales School of Medicine, Cardiff University, Heath Park, Cardiff, UK.
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38
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Kempisty B, Mostowska A, Górska I, Łuczak M, Czerski P, Szczepankiewicz A, Hauser J, Jagodziński PP. Association of 677C>T polymorphism of methylenetetrahydrofolate reductase (MTHFR) gene with bipolar disorder and schizophrenia. Neurosci Lett 2006; 400:267-71. [PMID: 16545905 DOI: 10.1016/j.neulet.2006.02.055] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2005] [Revised: 02/20/2006] [Accepted: 02/21/2006] [Indexed: 01/22/2023]
Abstract
Methylenetetrahydrofolate reductase (MTHFR) gene polymorphism 677C>T has been shown to be a risk factor for psychiatric disorders. We investigated the genotype and allelic frequencies of MTHFR 677C>T polymorphism in the group of patients with bipolar disorder type I (BDI) (n=200) and schizophrenia (n=200), and in the control group (n=300). Odds ratio (OR) for patients with BD and schizophrenia with 677T allele was 1.988 ((95% CI=1.370-2.883); P=0.0003 (P=0.0006 after Bonferroni correction)) and 1.796 ((95% CI=1.237-2.609); P=0.0020 (P=0.0040 after Bonferroni correction)), respectively. The stratification of patients based on gender revealed significant association of 677T allele with male patients with BDI and schizophrenia (OR=2.393; 95% CI=1.429-4.006; P=0.0008 and OR=2.036; 95% CI=1.207-3.433; P=0.0073, respectively). This finding indicates possible association of BD and schizophrenia with the 1p36.3 MTHFR locus.
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Affiliation(s)
- Bartosz Kempisty
- Department of Biochemistry and Molecular Biology, University of Medical Sciences, 6 Swiecickiego St., 60-781 Poznan, Poland
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Abstract
The enzyme catechol-O-methyl transferase (COMT), identified in the 1950s, is involved in catabolism of monoamines that are influenced by psychotropic medications, including neuroleptics and antidepressants. The COMT gene lies in a chromosomal region of interest for psychosis and bipolar spectrum disorder and a common polymorphism within the gene alters the activity of the enzyme. As a consequence, COMT has been one of the most studied genes for psychosis. On the basis of prior probabilities it would seem surprising if functional variation at COMT did not have some influence either on susceptibility to psychiatric phenotypes, modification of the course of illness or moderation of response to treatment. There is now robust evidence that variation at COMT influences frontal lobe function. However, despite considerable research effort, it has not proved straightforward to demonstrate and characterise a clear relationship between genetic variation at COMT and psychiatric phenotypes. It is of course, possible that COMT will turn out to be an unusually intractable case but it seems more likely that the experiences with this gene will provide a foretaste of the complexity of genotype-phenotype relationships that will be found for psychiatric traits. In this review, we consider the current state of evidence and the implications both for further studies of COMT and more generally for studies of other genes.
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Affiliation(s)
- N Craddock
- Department of Psychological Medicine, The Henry Wellcome Building for Biomedical Research in Wales, Cardiff University, School of Medicine, Heath Park, Cardiff, UK.
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40
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Abstract
Much work has been done to identify susceptibility genes in schizophrenia and bipolar disorder. Several well established linkages have emerged in schizophrenia. Strongly supported regions are 6p24-22, 1q21-22, and 13q32-34, while other promising regions include 8p21-22, 6q16-25, 22q11-12, 5q21-q33, 10p15-p11, and 1q42. Genomic regions of interest in bipolar disorder include 6q16-q22, 12q23-q24, and regions of 9p22-p21, 10q21-q22, 14q24-q32, 13q32-q34, 22q11-q22, and chromosome 18. Recently, specific genes or loci have been implicated in both disorders and, crucially, replicated. Current evidence supports NRG1, DTNBP1, DISC1, DAOA(G72), DAO, and RGS4 as schizophrenia susceptibility loci. For bipolar disorder the strongest evidence supports DAOA(G72) and BDNF. Increasing evidence suggests an overlap in genetic susceptibility across the traditional classification systems that dichotomised psychotic disorders into schizophrenia or bipolar disorder, most notably with association findings at DAOA(G72), DISC1, and NRG1. Future identification of psychosis susceptibility genes will have a major impact on our understanding of disease pathophysiology and will lead to changes in classification and the clinical practice of psychiatry.
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Affiliation(s)
- N Craddock
- Department of Psychological Medicine, The Henry Wellcome Building for Biomedical Research, Wales School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4XN, UK.
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Abstract
Though Kraepelin's century-old division of major mental illness into mood disorder and schizophrenia remains in place, debate abounds over the most appropriate classification. Although these arguments previously rested solely on clinical grounds, they now are rooted in genetics and neurobiology. This article reviews evidence from the fields of genetic epidemiology, linkage, association, cytogenetics, and gene expression. Taken together, these data suggest some overlap in the genes that predispose to bipolar disorder and schizophrenia. One gene, DAOA (D-amino acid oxidase activator, also known as G72), has been repeatedly implicated as an overlap gene, while DISC1 and others may constitute additional shared susceptibility genes. Further, some evidence implicates syndromes of co-occurring mood and psychotic symptoms in association with the putative risk alleles in overlap genes. From a nosologic perspective, the existence of overlap genes, coupled with the genotype-phenotype correlations discovered to date, supports the reality of the much debated schizoaffective disorder. Potential non-overlap syndromes--such as nonpsychotic bipolar disorder or cyclothymic temperament, on the one hand, and negative symptoms or the deficit syndrome, on the other--could turn out to have their own unique genetic determinants. If genotypes are to be the anchor points of a clinically useful system of classification, they must ultimately be shown to inform prognosis, treatment, and prevention. No gene variants have yet met these tests in bipolar disorder or schizophrenia.
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Affiliation(s)
- James B Potash
- Mood Disorders Program, Department of Psychiatry, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA.
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Takeuchi Y, Hashizume C, Chon EMH, Momozawa Y, Masuda K, Kikusui T, Mori Y. Canine tyrosine hydroxylase (TH) gene and dopamine beta -hydroxylase (DBH) gene: their sequences, genetic polymorphisms, and diversities among five different dog breeds. J Vet Med Sci 2006; 67:861-7. [PMID: 16210796 DOI: 10.1292/jvms.67.861] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Dopamine and noradrenaline are catecholamine neurotransmitters that are produced by biosynthetic enzymes such as tyrosine hydroxylase (TH) and dopamine beta -hydroxylase (DBH). As a first step to elucidate the genetic background of canine behavioral traits, we selected these genes as targets and sequenced these canine genes, and found that both were highly homologous with those of human beings. Then brain cDNAs derived from ten unrelated Beagles were used to search for polymorphisms in these genes. Four single nucleotide polymorphisms (SNPs) (C97T, G168A, G180A and C264T), one of which (C97T) will cause amino acid substitution in the TH gene, and two SNPs (C789A and A1819G), both of which will cause amino acid substitutions in the DBH gene were identified. The allelic frequencies among five dog breeds (47 Golden Retrievers, 41 Labrador Retrievers, 40 Malteses, 26 Miniature Schnauzers, and 39 Shibas) were examined and found to have significant variation between them with regards to all these SNPs, except for C97T in the TH gene and A1819G in the DBH gene. The polymorphisms of C97T and A1819G were found only in the Shiba. The present results suggest that the polymorphisms of the genes encoding catecholamine biosynthetic enzymes may become important markers for examining the genetic background of behavioral characteristics in dogs.
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Affiliation(s)
- J John Mann
- Department of Psychiatry, Division of Neuroscience, Columbia University, New York, New York 10032, USA
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44
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Abstract
It has been conventional for psychiatric research, including the search for predisposing genes, to proceed under the assumption that schizophrenia and bipolar disorder are separate disease entities with different underlying etiologies. These represent Emil Kraepelin's traditional dichotomous classification of the so-called "functional" psychoses and form the basis of modern diagnostic practice. However, findings emerging from many fields of psychiatric research do not fit well with this model. In particular, the pattern of findings emerging from genetic studies shows increasing evidence for an overlap in genetic susceptibility across the traditional classification categories-including association findings at DAOA(G72), DTNBP1 (dysbindin), COMT, BDNF, DISC1, and NRG1. The emerging evidence suggests the possibility of relatively specific relationships between genotype and psychopathology. For example, DISC1 and NRG1 may confer susceptibility to a form of illness with mixed features of schizophrenia and mania. The elucidation of genotype-phenotype relationships is at an early stage, but current findings highlight the need to consider alternative approaches to classification and conceptualization for psychiatric research rather than continuing to rely heavily on the traditional Kraepelinian dichotomy. As psychosis susceptibility genes are identified and characterized over the next few years, this will have a major impact on our understanding of disease pathophysiology and will lead to changes in classification and the clinical practice of psychiatry.
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Affiliation(s)
- Nick Craddock
- Department of Psychological Medicine, Wales School of Medicine, Cardiff University
| | - Michael C O'Donovan
- Department of Psychological Medicine, Wales School of Medicine, Cardiff University
| | - Michael J Owen
- Department of Psychological Medicine, Wales School of Medicine, Cardiff University
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45
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Abstract
Psychiatric disorders, including affective disorders (AD) and schizophrenia (SZ) are among the most common disabling brain diseases in Western populations and result in high costs in terms of morbidity as well as mortality. Although their etiology and pathophysiology is largely unknown, family-, twin-, and adoption studies argue for a strong genetic determination of these disorders. These studies indicate that there is between 40 and 85% heritability for these disorders but point also to the importance of environmental factors. Therefore, any research strategy aiming at the identification of genes involved in the development of AD and SZ should account for the complex nature (multifactorial) of these disorders. During the last decade, molecular genetic studies have contributed a great deal to the identification of genetic factors involved in complex disorders. Here we provide a comprehensive review of the most promising genes for AD and SZ, and the methods and approaches that were used for their identification. Also, we discuss the current knowledge and hypotheses that have been formulated regarding the effect of variations on protein functioning as well as recent observations that point to common molecular mechanisms.
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Affiliation(s)
- Ann Van Den Bogaert
- Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology, University of Antwerp, Antwerpen, Belgium
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46
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Abstract
Juvenile bipolar disorder (JBD) has been a subject of significant research and debate. Phenotypic differences between JBD and adult-onset bipolar disorder have led researchers to question whether or not similar neuropathologic mechanisms will be found. While much is known about the genetic and environmental contributions to the adult-onset phenotype, less is known about their contributions to JBD. Here, we review family, twin, adoption, and molecular genetic studies of JBD. Behavioral genetic data suggest both genetic and environmental contributions to JBD, while molecular genetic studies find linkage to age of onset of bipolar disorder to chromosomes 12p, 14q, and 15q. Additionally, changes associated with symptom age of onset have been recently reported in the brain-derived neurotrophic factor (BDNF) and glycogen synthase kinase 3-beta (GSK3-beta) genes. We contend that further progress in discovering the precise genetic and environmental contributions to JBD may depend on advances in phenotypic refinement, an increased appreciation of comorbid conditions, and more investigation of the longitudinal course of the disorder.
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Affiliation(s)
- Robert R Althoff
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
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47
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Wu XL, Macneil MD, De S, Xiao QJ, Michal JJ, Gaskins CT, Reeves JJ, Busboom JR, Wright RW, Jiang Z. Evaluation of candidate gene effects for beef backfat via Bayesian model selection. Genetica 2005; 125:103-13. [PMID: 16175458 DOI: 10.1007/s10709-005-5255-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2005] [Accepted: 04/10/2005] [Indexed: 10/25/2022]
Abstract
Candidate gene approaches provide tools for exploring and localizing causative genes affecting quantitative traits and the underlying variation may be better understood by determining the relative magnitudes of effects of their polymorphisms. Diacyglycerol O-acyltransferase 1 (DGAT1), fatty acid binding protein (heart) 3 (FABP3), growth hormone 1 (GH1), leptin (LEP) and thyroglobulin (TG) have been previously identified as genes contributing to genetic control of subcutaneous fat thickness (SFT) in beef cattle. In the present research, Bayesian model selection was used to evaluate effects of these five candidate genes by comparing competing non-nested models and treating candidate gene effects as either random or fixed. The analyses were implemented in SAS to simplify the programming and computation. Phenotypic data were gathered from a F(2) population of Wagyu x Limousin cattle. The five candidate genes had significant but varied effects on SFT in this population. Bayesian model selection identified the DGAT1 model as the one with the greatest model probability, whether candidate gene effects were considered random or fixed, and DGAT1 had the greatest additive effect on SFT. The SAS codes developed in the study are freely available and can be downloaded at: http://www.ansci.wsu.edu/programs/.
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Affiliation(s)
- Xiao-Lin Wu
- Department of Animal Sciences, Washington State University, Pullman, WA 99164-6351, USA
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Funke B, Malhotra AK, Finn CT, Plocik AM, Lake SL, Lencz T, DeRosse P, Kane JM, Kucherlapati R. COMT genetic variation confers risk for psychotic and affective disorders: a case control study. Behav Brain Funct 2005; 1:19. [PMID: 16232322 PMCID: PMC1282571 DOI: 10.1186/1744-9081-1-19] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2005] [Accepted: 10/18/2005] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Variation in the COMT gene has been implicated in a number of psychiatric disorders, including psychotic, affective and anxiety disorders. The majority of these studies have focused on the functional Val108/158Met polymorphism and yielded conflicting results, with limited studies examining the relationship between other polymorphisms, or haplotypes, and psychiatric illness. We hypothesized that COMT variation may confer a general risk for psychiatric disorders and have genotyped four COMT variants (Val158Met, rs737865, rs165599, and a SNP in the P2 promoter [-278A/G; rs2097603]) in 394 Caucasian cases and 467 controls. Cases included patients with schizophrenia (n = 196), schizoaffective disorder (n = 62), bipolar disorder (n = 82), major depression (n = 30), and patients diagnosed with either psychotic disorder NOS or depressive disorder NOS (n = 24). RESULTS SNP rs2097603, the Val/Met variant and SNP rs165599 were significantly associated (p = 0.004; p = 0.05; p = 0.035) with a broad "all affected" diagnosis. Haplotype analysis revealed a potentially protective G-A-A-A haplotype haplotype (-278A/G; rs737865; Val108/158Met; rs165599), which was significantly underrepresented in this group (p = 0.0033) and contained the opposite alleles of the risk haplotype previously described by Shifman et al. Analysis of diagnostic subgroups within the "all affecteds group" showed an association of COMT in patients with psychotic disorders as well as in cases with affective illness although the associated variants differed. The protective haplotype remained significantly underrepresented in most of these subgroups. CONCLUSION Our results support the view that COMT variation provides a weak general predisposition to neuropsychiatric disease including psychotic and affective disorders.
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Affiliation(s)
- Birgit Funke
- Harvard Partners Center for Genetics and Genomics, Boston, USA
| | - Anil K Malhotra
- Psychiatry Research, The Zucker Hillside Hospital, Glen Oaks, NY, USA
| | | | - Alex M Plocik
- Harvard Partners Center for Genetics and Genomics, Boston, USA
| | - Stephen L Lake
- Channing Laboratory, Brigham and Women's Hospital, Boston, USA
| | - Todd Lencz
- Psychiatry Research, The Zucker Hillside Hospital, Glen Oaks, NY, USA
| | - Pamela DeRosse
- Psychiatry Research, The Zucker Hillside Hospital, Glen Oaks, NY, USA
| | - John M Kane
- Psychiatry Research, The Zucker Hillside Hospital, Glen Oaks, NY, USA
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Abstract
OBJECTIVE To review the literature of the past decade covering the epidemiology, clinical characteristics, assessment, longitudinal course, biological and psychosocial correlates, and treatment and prevention of pediatric bipolar disorder (BD). METHOD A computerized search for articles published during the past 10 years was made and selected studies are presented. RESULTS Pediatric BD is increasingly recognized, and there are several prevailing views on core features of this disorder. The incidence and prevalence of the disorder and the associated comorbidities vary according to study setting and criteria used. This disorder is highly recurrent and accompanied by substantial psychiatric and psychosocial morbidity. Familial studies, including "top down" (offspring of parents with BD) and "bottom up" (relatives of youths with BD) studies indicate that pediatric BD is aggregated in families with adult or later-onset BD and suggest the existence of genetic predisposition. Greater understanding of the risk factors for early onset BD and recognition of the phenomenology of prodromal symptoms offers hope for early identification and prevention. Neuroimaging studies indicate frontotemporal and frontostriatal pathology, but none of these findings seems to be disorder specific. Combination pharmacotherapies appear promising, and the field awaits further short- and long-term randomized, placebo-controlled trials. Preliminary studies of various psychotherapies, including psychoeducation strategies tailored specifically for BD in youths, look encouraging. CONCLUSIONS Considerable advances have been made in our knowledge of pediatric BD; however, differing viewpoints on the clinical presentation of BD in children are the rule. Phenomenological and longitudinal studies and biological validation using genetic, neurochemical, neurophysiological, and neuroimaging methods may strengthen our understanding of the phenocopy. Randomized, controlled treatment studies for the acute and maintenance treatment of BD disorder are warranted.
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Affiliation(s)
- Mani N Pavuluri
- Pediatric Mood Disorders Clinic and Bipolar Research Program, Department of Psychiatry, University of Illinois at Chicago, 60612-7327, USA.
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Cho HJ, Meira-Lima I, Cordeiro Q, Michelon L, Sham P, Vallada H, Collier DA. Population-based and family-based studies on the serotonin transporter gene polymorphisms and bipolar disorder: a systematic review and meta-analysis. Mol Psychiatry 2005; 10:771-81. [PMID: 15824745 DOI: 10.1038/sj.mp.4001663] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The serotonin transporter (5-HTT) is a candidate gene for bipolar disorder (BPD). It has been investigated for association with the illness in a series of studies, but overall results have been inconsistent and its role in the disorder remains controversial. Systematic reviews using meta-analytical techniques are a useful method for objectively and reproducibly assessing individual studies and generating combined results. We performed two meta-analyses of published studies--both population-based and family-based studies--investigating the association between BPD and the 5-HTT gene-linked polymorphic region (5-HTTLPR) and the intron 2 variable numbers of tandem repeats (VNTR) polymorphisms. The literature was searched using Medline and Embase to identify studies for inclusion. We statistically joined population-based and family-based studies into a single meta-analysis. For both polymorphisms, our review revealed significant pooled odds ratios (ORs): 1.12 (95% CI 1.03-1.21) for the 5-HTTLPR and 1.12 (95% CI 1.02-1.22) for the intron 2 VNTR. Meta-regression showed that neither the study type (population-based vs family-based; P=0.41 for the 5-HTTLPR and P=0.91 for the intron 2 VNTR) nor the sample ethnicity (Caucasian vs non-Caucasian; P=0.35 for the 5-HTTLPR and P=0.66 for the intron 2 VNTR) significantly contributed to the heterogeneity of the meta-analyses. The observed ORs could be regarded simply as a very small but detectable effect of the 5-HTT, which has an additive effect when combined with other susceptibility loci. Alternative hypotheses on this finding were also discussed: a stronger effect of the haplotypes involving the two polymorphisms or other SNP markers; a more direct effect of these polymorphisms on specific phenotypes of BPD; and the presence of gene-environment interaction as a mediator of the genetic effects of 5-HTT.
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Affiliation(s)
- H J Cho
- Institute of Psychiatry, King's College London, London, UK.
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