Background
Variation in CACNA1C has consistently been associated with psychiatric disease in genome-wide association
studies. We have previously shown that healthy carriers of the CACNA1C rs1006737 risk variant exhibit hippocampal and perigenual anterior cingulate (pgACC)
dysfunction during episodic memory recall. To test whether this brain systems-level
abnormality is a potential intermediate phenotype for psychiatric disorder, we studied
unaffected relatives of patients with bipolar disorder, major depression, and schizophrenia.
Methods
The study population comprised 188 healthy first-degree relatives of patients with
bipolar disorder (n = 59), major depression (n = 73), and schizophrenia (n = 56) and 110 comparison subjects from our discovery study who were genotyped for
rs1006737 and underwent functional magnetic resonance imaging while performing an
episodic memory task and psychological testing. Group comparisons were analyzed using
SPM8 and PASW Statistics 20.
Results
Similar to risk allele carriers in the discovery sample, relatives of index patients
exhibited hippocampal and pgACC dysfunction as well as increased scores in depression
and anxiety measures, correlating negatively with hippocampal activation. Carrying
the rs1006737 risk variant resulted in a stronger decrease of hippocampal and pgACC
activation in relatives, indicating an additive effect of CACNA1C variation on familial risk.
Conclusions
Our findings implicate abnormal perigenual and hippocampal activation as a promising
intermediate phenotype for psychiatric disease and suggest a pathophysiologic mechanism
conferred by a CACNA1C variant being implicated in risk for symptom dimensions shared among bipolar disorder,
major depression, and schizophrenia.
Key Words
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to Biological PsychiatryAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- Schizophrenia as a complex trait: Evidence from a meta-analysis of twin studies.Arch Gen Psychiatry. 2003; 60: 1187-1192
- The heritability of bipolar affective disorder and the genetic relationship to unipolar depression.Arch Gen Psychiatry. 2003; 60: 497-502
- Genetic epidemiology of major depression: Review and meta-analysis.Am J Psychiatry. 2000; 157: 1552-1562
- Collaborative genome-wide association analysis supports a role for ANK3 and CACNA1C in bipolar disorder.Nat Genet. 2008; 40: 1056-1058
- Replication of bipolar disorder susceptibility alleles and identification of two novel genome-wide significant associations in a new bipolar disorder case-control sample.Mol Psychiatry. 2013; 18: 1302-1307
- Whole-genome association study of bipolar disorder.Mol Psychiatry. 2008; 13: 558-569
- The bipolar disorder risk allele at CACNA1C also confers risk of recurrent major depression and of schizophrenia.Mol Psychiatry. 2010; 15: 1016-1022
- Meta-analysis of genome-wide association data of bipolar disorder and major depressive disorder.Mol Psychiatry. 2011; 16: 2-4
- Genome-wide significant associations in schizophrenia to ITIH3/4, CACNA1C and SDCCAG8, and extensive replication of associations reported by the Schizophrenia PGC.Mol Psychiatry. 2013; 18: 708-712
- CACNA1C (rs1006737) is associated with schizophrenia.Mol Psychiatry. 2010; 15: 119-121
- Most genome-wide significant susceptibility loci for schizophrenia and bipolar disorder reported to date cross-traditional diagnostic boundaries.Hum Mol Genet. 2011; 20: 387-391
- CACNA1C (Ca(v)1.2) in the pathophysiology of psychiatric disease.Prog Neurobiol. 2012; 99: 1-14
- Identification of risk loci with shared effects on five major psychiatric disorders: A genome-wide analysis.Lancet. 2013; 381: 1371-1379
- Role of hippocampal Cav1.2 Ca2+ channels in NMDA receptor-independent synaptic plasticity and spatial memory.J Neurosci. 2005; 25: 9883-9892
- The endophenotype concept in psychiatry: Etymology and strategic intentions.Am J Psychiatry. 2003; 160: 636-645
- Intermediate phenotypes and genetic mechanisms of psychiatric disorders.Nat Rev Neurosci. 2006; 7: 818-827
- Hippocampal pathology in schizophrenia.Curr Top Behav Neurosci. 2010; 4: 529-553
- The hippocampal formation in schizophrenia.Am J Psychiatry. 2010; 167: 1178-1193
- The hippocampus in major depression: Evidence for the convergence of the bench and bedside in psychiatric research?.Mol Psychiatry. 2011; 16: 252-264
- Toward constructing an endophenotype strategy for bipolar disorders.Biol Psychiatry. 2006; 60: 93-105
- Calcium channel antagonists for the treatment of bipolar disorder.Bipolar Disord. 2000; 2: 108-119
- Genetic variation in CACNA1C affects brain circuitries related to mental illness.Arch Gen Psychiatry. 2010; 67: 939-945
- The challenges and promise of neuroimaging in psychiatry.Neuron. 2012; 73: 8-22
- The impact of the CACNA1C gene polymorphism on frontolimbic function in bipolar disorder.Mol Psychiatry. 2011; 16: 1070-1071
- CACNA1C risk variant and amygdala activity in bipolar disorder, schizophrenia and healthy controls.PloS One. 2013; 8: e56970
- Brain function in carriers of a genome-wide supported bipolar disorder variant.Arch Gen Psychiatry. 2010; 67: 803-811
- Functional impact of a recently identified quantitative trait locus for hippocampal volume with genome-wide support.Transl Psychiatry. 2013; 3: e287
- A neural model of voluntary and automatic emotion regulation: implications for understanding the pathophysiology and neurodevelopment of bipolar disorder.Mol Psychiatry. 2008; 13: 833-857
- Neural mechanisms of social risk for psychiatric disorders.Nat Neurosci. 2012; 15: 663-668
- The role of the ventromedial prefrontal cortex in memory consolidation.Behav Brain Res. 2011; 218: 325-334
- A genome-wide supported variant in CACNA1C influences hippocampal activation during episodic memory encoding and retrieval [published online ahead of print July 17].Eur Arch Psychiatry Clin Neurosci. 2013;
- Multimodal meta-analysis of structural and functional brain changes in first episode psychosis and the effects of antipsychotic medication.Neurosci Biobehav Rev. 2012; 36: 2325-2333
- Amygdalar and hippocampal substrates of anxious temperament differ in their heritability.Nature. 2010; 466: 864-868
- Genetic influences on human brain structure: a review of brain imaging studies in twins.Hum Brain Mapp. 2007; 28: 464-473
- Hippocampal function in healthy carriers of the CLU Alzheimer’s disease risk variant.J Neurosci. 2011; 31: 18180-18184
- Statistical epistasis and functional brain imaging support a role of voltage-gated potassium channels in human memory.PloS One. 2011; 6: e29337
- Common Kibra alleles are associated with human memory performance.Science. 2006; 314: 475-478
- Genetics of human episodic memory: Dealing with complexity.Trends Cogn Sci. 2011; 15: 381-387
- Genetics and intermediate phenotypes of the schizophrenia—bipolar disorder boundary.Neurosci Biobehav Rev. 2010; 34: 897-921
- Stress and hippocampal plasticity: Implications for the pathophysiology of affective disorders.Hum Psychopharmacol. 2001; 16: S7-S19
- Stress-induced changes in hippocampal function.Prog Brain Res. 2008; 167: 3-15
- Developmental pathology, dopamine, stress and schizophrenia.Int J Dev Neurosci. 2011; 29: 207-213
- Hippocampal volume as marker of daily life stress sensitivity in psychosis.Psychol Med. 2013; 43: 1377-1387
- Stress and the brain: From adaptation to disease.Nat Rev Neurosci. 2005; 6: 463-475
- Glucocorticoids specifically enhance L-type calcium current amplitude and affect calcium channel subunit expression in the mouse hippocampus.J Neurophysiol. 2007; 97: 5-14
- Corticosteroid effects on calcium signaling in limbic neurons.Cell Calcium. 2012; 51: 277-283
- The molecular neurobiology of depression.Nature. 2008; 455: 894-902
- Chronic stress alters neural activity in medial prefrontal cortex during retrieval of extinction.Neuroscience. 2011; 174: 115-131
- Repeated stress alters dendritic spine morphology in the rat medial prefrontal cortex.J Comp Neurol. 2008; 507: 1141-1150
- The CACNA1C and ANK3 risk alleles impact on affective personality traits and startle reactivity but not on cognition or gating in healthy males.Bipolar Disord. 2011; 13: 250-259
- Forebrain elimination of cacna1c mediates anxiety-like behavior in mice.Mol Psychiatry. 2012; 17: 1054-1055
Article info
Publication history
Published online: December 09, 2013
Accepted:
November 22,
2013
Received in revised form:
November 21,
2013
Received:
July 16,
2013
Footnotes
Authors SE and AM-L contributed equally to this work.
Identification
Copyright
© 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
ScienceDirect
Access this article on ScienceDirectLinked Article
- Imaging Genetics Approaches to Identify Mechanisms in Severe Mental IllnessBiological PsychiatryVol. 76Issue 6
- PreviewSchizophrenia, bipolar disorder, and major depressive disorders are heritable serious mental illnesses (SMI). What does this heritability mean? What are the underlying mechanisms? Large genome-wide association studies (GWAS) have identified both shared and unique genetic risk variants for these disorders; however, causal risk variants, their molecular mechanisms, and their effects on brain circuitry are mostly unknown. Targeted, possibly individualized, therapies addressing underlying mechanisms offer the promise of improved functioning and well-being for patients.
- Full-Text
- Preview