1
|
Haybaeck J, Postruznik M, Miller CL, Dulay JR, Llenos IC, Weis S. Increased expression of retinoic acid-induced gene 1 in the dorsolateral prefrontal cortex in schizophrenia, bipolar disorder, and major depression. Neuropsychiatr Dis Treat 2015; 11:279-89. [PMID: 25678793 PMCID: PMC4322876 DOI: 10.2147/ndt.s72536] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Retinoids regulate gene expression in different cells and tissues at the transcriptional level. Retinoic acid transcriptionally regulates downstream regulatory molecules, including enzymes, transcription factors, cytokines, and cytokine receptors. Animal models indicate an involvement of retinoid signaling pathways in the regulation of synaptic plasticity and learning, especially in the hippocampus. Retinoic acid-inducible or induced gene 1 (RAI-1) is induced during neuronal differentiation, and was associated with the severity of the phenotype and response to medication in schizophrenic patients. METHODS In the present study, we used immunohistochemistry to investigate the expression of RAI-1 in 60 brains from the Stanley Neuropathology Consortium (15 cases each from controls and from patients with schizophrenia, bipolar disorder, and major depression). Rating scores for density and intensity were determined in the dorsolateral prefrontal cortex. RESULTS All four groups showed high interindividual variation. RAI-1-positive cells were identified as neurons and astrocytes. Significantly increased intensities in cortical neurons were noted in all three major psychiatric groups compared with controls. The density of RAI-1-positive neurons was increased (P=0.06) in schizophrenia and bipolar disorder. In bipolar disorder, RAI-1-positive astrocytes in gray matter showed a significantly increased intensity and compound value. Thus, a significant increase in the parameters measured was found in schizophrenia, bipolar disorder, and major depression. CONCLUSION Our study shows a significant increase in expression of RAI-1 in the brains from patients with schizophrenia, bipolar disorder, or major depression. The increased expression might reflect altered signaling pathways, like that for retinoic acid. The underlying mechanisms leading to the increased expression and its functional consequences are so far unknown, and remain to be investigated in future studies.
Collapse
Affiliation(s)
- Johannes Haybaeck
- Department of Neuropathology, Institute of Pathology, Medical University Graz, Graz, Austria
| | - Magdalena Postruznik
- Department of Neuropathology, Institute of Pathology, Medical University Graz, Graz, Austria
| | | | - Jeannette R Dulay
- Laboratory of Brain Research and Neuropathology, Departments of Psychiatry and Pathology, Uniformed Services University of the Health Sciences, and Stanley Medical Research Institute, Bethesda, MD, USA
| | - Ida C Llenos
- Laboratory of Brain Research and Neuropathology, Departments of Psychiatry and Pathology, Uniformed Services University of the Health Sciences, and Stanley Medical Research Institute, Bethesda, MD, USA ; Laboratory of Neuropathology, Department of Pathology and Neuropathology, State Neuropsychiatric Hospital Wagner-Jauregg, Medical School, Johannes Kepler University, Linz, Austria
| | - Serge Weis
- Laboratory of Brain Research and Neuropathology, Departments of Psychiatry and Pathology, Uniformed Services University of the Health Sciences, and Stanley Medical Research Institute, Bethesda, MD, USA ; Laboratory of Neuropathology, Department of Pathology and Neuropathology, State Neuropsychiatric Hospital Wagner-Jauregg, Medical School, Johannes Kepler University, Linz, Austria
| |
Collapse
|
2
|
Kandaswamy R, McQuillin A, Curtis D, Gurling H. Allelic association, DNA resequencing and copy number variation at the metabotropic glutamate receptor GRM7 gene locus in bipolar disorder. Am J Med Genet B Neuropsychiatr Genet 2014; 165B:365-72. [PMID: 24804643 PMCID: PMC4231221 DOI: 10.1002/ajmg.b.32239] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 04/14/2014] [Indexed: 12/12/2022]
Abstract
Genetic markers at the GRM7 gene have shown allelic association with bipolar disorder (BP) in several case-control samples including our own sample. In this report, we present results of resequencing the GRM7 gene in 32 bipolar samples and 32 random controls selected from 553 bipolar cases and 547 control samples (UCL1). Novel and potential etiological base pair changes discovered by resequencing were genotyped in the entire UCL case-control sample. We also report on the association between GRM7 and BP in a second sample of 593 patients and 642 controls (UCL2). The three most significantly associated SNPs in the original UCL1 BP GWAS sample were genotyped in the UCL2 sample, of which none were associated. After combining the genotype data for the two samples only two (rs1508724 and rs6769814) of the original three SNP markers remained significantly associated with BP. DNA sequencing revealed mutations in three cases which were absent in control subjects. A 3'-UTR SNP rs56173829 was found to be significantly associated with BP in the whole UCL sample (P = 0.035; OR = 0.482), the rare allele being less common in cases compared to controls. Bioinformatic analyses predicted a change in the centroid secondary structure of RNA and alterations in the miRNA binding sites for the mutated base of rs56173829. We also validated two deletions and a duplication within GRM7 using quantitative-PCR which provides further support for the pre-existing evidence that copy number variants at GRM7 may have a role in the etiology of BP.
Collapse
Affiliation(s)
- Radhika Kandaswamy
- Molecular Psychiatry Laboratory, Mental Health Sciences Unit, Faculty of Brain Sciences, University College LondonLondon, UK
| | - Andrew McQuillin
- Molecular Psychiatry Laboratory, Mental Health Sciences Unit, Faculty of Brain Sciences, University College LondonLondon, UK,* Correspondence to: Andrew McQuillin, Molecular Psychiatry Laboratory, Mental Health Sciences Unit, Faculty of Brain Sciences, University College London, Rockefeller Building, 21 University Street, London WC1E 6BT, UK. E-mail:
| | - David Curtis
- Department of Psychological Medicine, St. Bartholomew's and the Royal London School of Medicine and Dentistry, Queen Mary University of LondonLondon, UK
| | - Hugh Gurling
- Molecular Psychiatry Laboratory, Mental Health Sciences Unit, Faculty of Brain Sciences, University College LondonLondon, UK
| |
Collapse
|
3
|
A protective-compensatory model may reconcile the genetic and the developmental findings in schizophrenia. Schizophr Res 2013; 144:9-15. [PMID: 23360726 DOI: 10.1016/j.schres.2012.12.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 12/12/2012] [Accepted: 12/14/2012] [Indexed: 12/12/2022]
Abstract
OBJECTIVE The neurodevelopmental, the multifactorial-oligogenic and the gene-environment diathesis models have provoked advances in schizophrenia research, yet the exact pathophysiology remains indefinable. We broadened our analysis of 20years of findings in adults and children descending from densely affected families in the Québec population with a founder effect. The goal was to inspect the link between these family-genetic and developmental findings. METHOD 48 multigenerational families affected by schizophrenia or bipolar disorder represented a quasi-total sample of affected kindreds in the Eastern-Quebec catchment area. Among the 1274 adult family members with lifetime best-estimate diagnoses, 341 had DSM-IV schizophrenia or bipolar disorder. Young offspring of an affected parent were studied with the same clinical, physiological and cognitive measures as the adults. RESULTS Four new observations emerged: 1. A striking resemblance between the clinical, neuropsychological and genetic findings in these densely affected families and those reported in sporadic samples; 2. A high degree of heterogeneity despite the origin from a founder-effect population; 3. Cognitive deficits in some non-affected adult relatives as severe as those in patients; 4. Children descending from kindreds displayed neurodevelopmental endophenotypic anomalies comparable to those of adult patients. CONCLUSION These four observations could be reconciled under the hypothesis that highly familial and sporadic cases share mechanisms based on defective protective genes, a model to an extent similar to cancer findings. These defective protective genes running in families would longitudinally disturb the compensatory mechanisms in children inheriting them and might be at the core of the schizophrenia process.
Collapse
|
4
|
Kukshal P, Bhatia T, Bhagwat AM, Gur RE, Gur RC, Deshpande SN, Nimgaonkar VL, Thelma BK. Association study of neuregulin-1 gene polymorphisms in a North Indian schizophrenia sample. Schizophr Res 2013; 144:24-30. [PMID: 23360725 PMCID: PMC4040109 DOI: 10.1016/j.schres.2012.12.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 11/20/2012] [Accepted: 12/17/2012] [Indexed: 02/07/2023]
Abstract
BACKGROUND Neuregulin-1 (NRG1) gene polymorphisms have been proposed as risk factors for several common disorders. Associations with cognitive variation have also been tested. With regard to schizophrenia (SZ) risk, studies of Caucasian ancestry samples indicate associations more consistently than East Asian samples, suggesting heterogeneity. To exploit the differences in linkage disequilibrium (LD) structure across ethnic groups, we conducted a SZ case-control study (that included cognitive evaluations) in a sample from the north Indian population. METHODS NRG1 variants (n=35 SNPs, three microsatellite markers) were initially analyzed among cases (DSM IV criteria, n=1007) and controls (n=1019, drawn from two groups) who were drawn from the same geographical region in North India. Nominally significant associations with SZ were next analyzed in relation to neurocognitive measures estimated with a computerized neurocognitive battery in a subset of the sample (n=116 cases, n=170 controls). RESULTS Three variants and one microsatellite showed allelic association with SZ (rs35753505, rs4733263, rs6994992, and microsatellite 420M9-1395, p≤0.05 uncorrected for multiple comparisons). A six marker haplotype 221121 (rs35753505-rs6994992-rs1354336-rs10093107-rs3924999-rs11780123) showed (p=0.0004) association after Bonferroni corrections. Regression analyses with the neurocognitive measures showed nominal (uncorrected) associations with emotion processing and attention at rs35753505 and rs6994992, respectively. CONCLUSIONS Suggestive associations with SZ and SZ-related neurocognitive measures were detected with two SNPs from the NRG1 promoter region in a north Indian cohort. The functional role of the alleles merits further investigation.
Collapse
Affiliation(s)
- Prachi Kukshal
- Department of Genetics, University of Delhi South campus, Benito
Juarez Road, New Delhi – 110 021, India
- C.B. Patel Research Centre, Vile Parle (West), Mumbai, India
| | - Triptish Bhatia
- Department of Psychiatry, Dr. RML Hospital, New Delhi – 110
001, India
| | - A. M. Bhagwat
- C.B. Patel Research Centre, Vile Parle (West), Mumbai, India
| | - Raquel E. Gur
- Department of Psychiatry, Neuropsychiatry Section, University of
Pennsylvania, Philadelphia, PA, USA
| | - Ruben C. Gur
- Department of Psychiatry, Neuropsychiatry Section, University of
Pennsylvania, Philadelphia, PA, USA
| | | | - Vishwajit L. Nimgaonkar
- Department of Psychiatry and Human Genetics, Western Psychiatric
Institute and Clinic, University of Pittsburgh School of Medicine and Graduate
School of Public Health, 3811 O’Hara Street, Pittsburgh, PA 15213, USA
| | - B. K. Thelma
- Department of Genetics, University of Delhi South campus, Benito
Juarez Road, New Delhi – 110 021, India
| |
Collapse
|
5
|
Kerner B, Rao AR, Christensen B, Dandekar S, Yourshaw M, Nelson SF. Rare Genomic Variants Link Bipolar Disorder with Anxiety Disorders to CREB-Regulated Intracellular Signaling Pathways. Front Psychiatry 2013; 4:154. [PMID: 24348429 PMCID: PMC3842585 DOI: 10.3389/fpsyt.2013.00154] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 11/09/2013] [Indexed: 11/28/2022] Open
Abstract
Bipolar disorder is a common, complex, and severe psychiatric disorder with cyclical disturbances of mood and a high suicide rate. Here, we describe a family with four siblings, three affected females and one unaffected male. The disease course was characterized by early-onset bipolar disorder and co-morbid anxiety spectrum disorders that followed the onset of bipolar disorder. Genetic risk factors were suggested by the early onset of the disease, the severe disease course, including multiple suicide attempts, and lack of adverse prenatal or early life events. In particular, drug and alcohol abuse did not contribute to the disease onset. Exome sequencing identified very rare, heterozygous, and likely protein-damaging variants in eight brain-expressed genes: IQUB, JMJD1C, GADD45A, GOLGB1, PLSCR5, VRK2, MESDC2, and FGGY. The variants were shared among all three affected family members but absent in the unaffected sibling and in more than 200 controls. The genes encode proteins with significant regulatory roles in the ERK/MAPK and CREB-regulated intracellular signaling pathways. These pathways are central to neuronal and synaptic plasticity, cognition, affect regulation and response to chronic stress. In addition, proteins in these pathways are the target of commonly used mood-stabilizing drugs, such as tricyclic antidepressants, lithium, and valproic acid. The combination of multiple rare, damaging mutations in these central pathways could lead to reduced resilience and increased vulnerability to stressful life events. Our results support a new model for psychiatric disorders, in which multiple rare, damaging mutations in genes functionally related to a common signaling pathway contribute to the manifestation of bipolar disorder.
Collapse
Affiliation(s)
- Berit Kerner
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles , Los Angeles, CA , USA
| | - Aliz R Rao
- Department of Human Genetics, University of California Los Angeles , Los Angeles, CA , USA
| | | | - Sugandha Dandekar
- Department of Human Genetics, University of California Los Angeles , Los Angeles, CA , USA
| | - Michael Yourshaw
- Department of Human Genetics, University of California Los Angeles , Los Angeles, CA , USA
| | - Stanley F Nelson
- Department of Human Genetics, University of California Los Angeles , Los Angeles, CA , USA ; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles , Los Angeles, CA , USA ; Department of Pathology and Laboratory Medicine, University of California Los Angeles , Los Angeles, CA , USA
| |
Collapse
|
6
|
Abstract
Schizophrenia (SZ) is a common disorder that runs in families. It has a relatively high heritability, i.e., inherited factors account for the major proportion of its etiology. The high heritability has motivated gene mapping studies that have improved in sophistication through the past two decades. Belying earlier expectations, it is now becoming increasingly clear that the cause of SZ does not reside in a single mutation, or even in a single gene. Rather, there are multiple DNA variants, not all of which have been identified. Additional risk may be conferred by interactions between individual DNA variants, as well as 'gene-environment' interactions. We review studies that have accounted for a fraction of the heritability. Their relevance to the practising clinician is discussed. We propose that continuing research in DNA variation, in conjunction with rapid ongoing advances in allied fields, will yield dividends from the perspective of diagnosis, treatment prediction through pharmacogenetics, and rational treatment through discoveries in pathogenesis.
Collapse
Affiliation(s)
- Prachi Kukshal
- Department of Genetics, University of Delhi South Campus, New Delhi, India
| | - B. K. Thelma
- Department of Genetics, University of Delhi South Campus, New Delhi, India
| | - Vishwajit L. Nimgaonkar
- Departments of Psychiatry and Human Genetics, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine and Graduate School of Public Health, Pittsburgh, Pennsylvania, USA
| | - Smita N. Deshpande
- Department of Psychiatry, Post Graduate Institute of Medical Education and Research, Dr Ram Manohar Lohia Hospital, New Delhi, India
| |
Collapse
|
7
|
Tao R, Li C, Newburn EN, Ye T, Lipska BK, Herman MM, Weinberger DR, Kleinman JE, Hyde TM. Transcript-specific associations of SLC12A5 (KCC2) in human prefrontal cortex with development, schizophrenia, and affective disorders. J Neurosci 2012; 32:5216-22. [PMID: 22496567 PMCID: PMC3752043 DOI: 10.1523/jneurosci.4626-11.2012] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 02/09/2012] [Accepted: 02/10/2012] [Indexed: 01/14/2023] Open
Abstract
The neuron-specific K(+)-Cl(-) cotransporter SLC12A5, also known as KCC2, helps mediate the electrophysiological effects of GABA. The pattern of KCC2 expression during early brain development suggests that its upregulation drives the postsynaptic switch of GABA from excitation to inhibition. We previously found decreased expression of full-length KCC2 in the postmortem hippocampus of patients with schizophrenia, but not in the dorsolateral prefrontal cortex (DLPFC). Using PCR and rapid amplification of cDNA ends, we discovered several previously unrecognized alternative KCC2 transcripts in both human adult and fetal brain in addition to the previously identified full-length (NM_020708.3) and truncated (AK098371) transcripts. We measured the expression levels of four relatively abundant truncated splice variants, including three novel transcripts (ΔEXON6, EXON2B, and EXON6B) and one previously described transcript (AK098371), in a large human cohort of nonpsychiatric controls across the lifespan, and in patients with schizophrenia and affective disorders. In SH-SY5Y cell lines, these transcripts were translated into proteins and expressed at their predicted sizes. Expression of the EXON6B transcript is increased in the DLPFC of patients with schizophrenia (p = 0.03) but decreased in patients with major depression (p = 0.04). The expression of AK098371 is associated with a GAD1 single nucleotide polymorphism (rs3749034) that previously has been associated with GAD67 expression and risk for schizophrenia. Our data confirm the developmental regulation of KCC2 expression, and provide evidence that KCC2 transcripts are differentially expressed in schizophrenia and affective disorders. Alternate transcripts from KCC2 may participate in the abnormal GABA signaling in the DLPFC associated with schizophrenia.
Collapse
Affiliation(s)
- Ran Tao
- Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-1385, and
| | - Chao Li
- Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-1385, and
| | - Erin N. Newburn
- Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-1385, and
| | - Tianzhang Ye
- Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-1385, and
- The Lieber Institute for Brain Development, Johns Hopkins University Medical Center, Baltimore, Maryland 21205
| | - Barbara K. Lipska
- Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-1385, and
| | - Mary M. Herman
- Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-1385, and
| | - Daniel R. Weinberger
- Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-1385, and
- The Lieber Institute for Brain Development, Johns Hopkins University Medical Center, Baltimore, Maryland 21205
| | - Joel E. Kleinman
- Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-1385, and
| | - Thomas M. Hyde
- Clinical Brain Disorders Branch, Genes, Cognition and Psychosis Program, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-1385, and
- The Lieber Institute for Brain Development, Johns Hopkins University Medical Center, Baltimore, Maryland 21205
| |
Collapse
|
8
|
Valiente A, Lafuente A, Bernardo M. [Systematic review of the Genomewide Association Studies (GWAS) in schizophrenia]. REVISTA DE PSIQUIATRIA Y SALUD MENTAL 2011; 4:218-27. [PMID: 23446268 DOI: 10.1016/j.rpsm.2011.09.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 08/01/2011] [Accepted: 09/30/2011] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Heritability in schizophrenia can reach up to 80% and the risk in families is 5-10 times higher than in the general population. The large contribution of genetics in this disorder has led to a growing interest in its study. OBJECTIVES To review the findings of genetic studies known as Genomewide Association Studies (GWAS) on schizophrenia. METHOD Systematic search using Pubmed with the key words GWAS and (psychosis) or (schizophrenia). The following web pages have been reviewed: http://www.szgene.org/largescale.asp and www.genome.gov/gwastudies/. RESULTS The GWAS have focused on causal biological aspects, such as the histocompatibility complex, glutamate metabolism, apoptosis and inflammatory processes, and the immune system (TNF-β, TNFR1). Also focused in the search were the genes that modulate the appearance of secondary metabolic and cardiac effects and secondary effects in subjects with schizophrenia and on anti-psychotic treatment. In neurorecognition, over-expression of the MET proto-oncogene (MET) has been associated with a low susceptibility for schizophrenia and a better cognitive performance, as well as a lower susceptibility for the incidence of cancer. Mention is also made of the different genes that mediate in cognitive functioning depending on the anti-psychotic treatment received. CONCLUSIONS The main interests of the GWAS during the last few years have been the neurobiological pathways involved in schizophrenia. The discoveries arising from these studies have been limited. This has led to an innovative approach on the aetiological study of the disorder by studying gene-environment interactions.
Collapse
Affiliation(s)
- Alicia Valiente
- Programa Esquizofrènia Clínic, Servei de Psiquiatria, Hospital Clínic, IDIBAPS, Universitat de Barcelona, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, España.
| | | | | |
Collapse
|
9
|
Expression profiling in neuropsychiatric disorders: emphasis on glutamate receptors in bipolar disorder. Pharmacol Biochem Behav 2011; 100:705-11. [PMID: 22005598 DOI: 10.1016/j.pbb.2011.09.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Revised: 09/20/2011] [Accepted: 09/30/2011] [Indexed: 02/08/2023]
Abstract
Functional genomics and proteomics approaches are being employed to evaluate gene and encoded protein expression changes with the tacit goal to find novel targets for drug discovery. Genome-wide association studies (GWAS) have attempted to identify valid candidate genes through single nucleotide polymorphism (SNP) analysis. Furthermore, microarray analysis of gene expression in brain regions and discrete cell populations has enabled the simultaneous quantitative assessment of relevant genes. The ability to associate gene expression changes with neuropsychiatric disorders, including bipolar disorder (BP), and their response to therapeutic drugs provides a novel means for pharmacotherapeutic interventions. This review summarizes gene and pathway targets that have been identified in GWAS studies and expression profiling of human postmortem brain in BP, with an emphasis on glutamate receptors (GluRs). Although functional genomic assessment of BP is in its infancy, results to date point towards a dysregulation of GluRs that bear some similarity to schizophrenia (SZ), although the pattern is complex, and likely to be more complementary than overlapping. The importance of single population expression profiling of specific neurons and intrinsic circuits is emphasized, as this approach provides informative gene expression profile data that may be underappreciated in regional studies with admixed neuronal and non-neuronal cell types.
Collapse
|
10
|
Koefoed P, Andreassen OA, Bennike B, Dam H, Djurovic S, Hansen T, Jorgensen MB, Kessing LV, Melle I, Møller GL, Mors O, Werge T, Mellerup E. Combinations of SNPs related to signal transduction in bipolar disorder. PLoS One 2011; 6:e23812. [PMID: 21897858 PMCID: PMC3163586 DOI: 10.1371/journal.pone.0023812] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 07/28/2011] [Indexed: 11/18/2022] Open
Abstract
Any given single nucleotide polymorphism (SNP) in a genome may have little or no functional impact. A biologically significant effect may possibly emerge only when a number of key SNP-related genotypes occur together in a single organism. Thus, in analysis of many SNPs in association studies of complex diseases, it may be useful to look at combinations of genotypes. Genes related to signal transmission, e.g., ion channel genes, may be of interest in this respect in the context of bipolar disorder. In the present study, we analysed 803 SNPs in 55 genes related to aspects of signal transmission and calculated all combinations of three genotypes from the 3×803 SNP genotypes for 1355 controls and 607 patients with bipolar disorder. Four clusters of patient-specific combinations were identified. Permutation tests indicated that some of these combinations might be related to bipolar disorder. The WTCCC bipolar dataset were use for replication, 469 of the 803 SNP were present in the WTCCC dataset either directly (n = 132) or by imputation (n = 337) covering 51 of our selected genes. We found three clusters of patient-specific 3×SNP combinations in the WTCCC dataset. Different SNPs were involved in the clusters in the two datasets. The present analyses of the combinations of SNP genotypes support a role for both genetic heterogeneity and interactions in the genetic architecture of bipolar disorder.
Collapse
Affiliation(s)
- Pernille Koefoed
- Laboratory of Neuropsychiatry, Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|