Esslinger C, Kirsch P, Haddad L, Mier D, Sauer C, Erk S et al. Cognitive state and connectivity effects of the genome-wide significant psychosis variant in ZNF804A. Neuroimage 54: 2514-2523
ABSTRACT Alterations of connectivity are central to the systems-level pathophysiology of schizophrenia. One of the best-established genome-wide significant risk variants for this highly heritable disorder, the rs1344706 single nucleotide polymorphism in ZNF804A, was recently shown to modulate connectivity in healthy carriers during working memory (WM) in a pattern mirroring that which was found in overt disease. However, it was unclear whether this finding is specific to WM or if it is present regardless of cognitive state. Therefore, we examined genotype effects on connectivity in healthy carriers during rest and an emotion processing task without WM component. 111 healthy German subjects performed a battery of functional imaging tasks. Functional connectivity with the right dorsolateral prefrontal cortex during rest and an implicit emotion recognition task was determined using the seed voxel method and compared to results during WM. During rest and during the emotional task, a pattern of reduced interhemispheric prefrontal connectivity with increasing number of rs1344706 risk alleles could be seen that was close to identical to that during WM, suggesting a state-independent influence of the genetic variant on interhemispheric processing, possibly through structural effects. By contrast, the abnormal prefronto-hippocampal connectivity was only seen during the WM task, indicating a degree of task specificity in agreement with prior results in patients with schizophrenia. Our findings confirm a key role for disturbed functional connectivity in the genetic risk architecture of schizophrenia and identify cognitive state-dependent and independent components with regard to WM function.
- SourceAvailable from: Eric H Chang
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- "It was the first gene to reach genome-wide significance for psychosis (O'Donovan et al., 2008), and its association with both schizophrenia and bipolar disorder has been subsequently confirmed in multiple genome-wide association studies (GWASs; Riley et al., 2010; Williams et al., 2011; Zhang et al., 2011). Studies of the single nucleotide polymorphism (SNP) rs1344706 in both psychiatric patients and healthy risk allele carriers have demonstrated effects on white and gray matter volume, white matter tract integrity, functional connectivity (Esslinger et al., 2009; Lencz et al., 2010; Voineskos et al., 2011; Ikuta et al., 2014; Wei et al., 2015), and cognition (Hashimoto et al., 2010; Walters et al., 2010; Esslinger et al., 2011; Walter et al., 2011; Chen et al., 2012), indicating potential functional consequences of this gene variant. While these findings illustrate the potential wide-ranging effects of a ZNF804A polymorphism, little is known about the biological functions of the gene itself. "
ABSTRACT: The zinc finger protein ZNF804A rs1344706 variant is a replicated genome-wide significant risk variant for schizophrenia and bipolar disorder. While its association with altered brain structure and cognition in patients and healthy risk allele carriers is well documented, the characteristics and function of the gene in the brain remains poorly understood. Here, we used in situ hybridization to determine mRNA expression levels of the ZNF804A rodent homologue, Zfp804a, across multiple postnatal neurodevelopmental time points in the rat brain. We found changes in Zfp804a expression in the rat hippocampus, frontal cortex, and thalamus across postnatal neurodevelopment. Zfp804a mRNA peaked at postnatal day (P) 21 in hippocampal CA1 and DG regions and was highest in the lower cortical layers of frontal cortex at P1, possibly highlighting a role in developmental migration. Using immunofluorescence, we found that Zfp804a mRNA and ZFP804A co-localized with neurons and not astrocytes. In primary cultured cortical neurons, we found that Zfp804a expression was significantly increased when neurons were exposed to glutamate [20μM], but this increase was blocked by the N-methyl-d-aspartate receptor (NMDAR) antagonist MK-801. Expression of Comt, Pde4b, and Drd2, genes previously shown to be regulated by ZNF804A overexpression, was also significantly changed in an NMDA-dependent manner. Our results describe, for the first time, the unique postnatal neurodevelopmental expression of Zfp804a in the rodent brain and demonstrate that glutamate potentially plays an important role in the regulation of this psychiatric susceptibility gene. These are critical steps toward understanding the biological function of ZNF804A in the mammalian brain. Copyright © 2015 Elsevier B.V. All rights reserved.Schizophrenia Research 07/2015; DOI:10.1016/j.schres.2015.06.023 · 4.43 Impact Factor
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- "It is notable that we found ZNF804A-related changes in hippocampus-PFC coactivation in the resting state. This is in contrast to a previous study, which showed no ZNF804A-related differences in dorsolateral PFChippocampus functional connectivity at rest [Esslinger et al., 2011]. One reason for this discrepancy may be differences in the analysis approach used. "
ABSTRACT: Hippocampal theta-band oscillations are thought to facilitate the co-ordination of brain activity across distributed networks, including between the hippocampus and prefrontal cortex (PFC). Impairments in hippocampus-PFC functional connectivity are implicated in schizophrenia and are associated with a polymorphism within the ZNF804A gene that shows a genome-wide significant association with schizophrenia. However, the mechanisms by which ZNF804A affects hippocampus-PFC connectivity are unknown. We used a multimodal imaging approach to investigate the impact of the ZNF804A polymorphism on hippocampal theta and hippocampal network coactivity. Healthy volunteers homozygous for the ZNF804A rs1344706 (A[risk]/C[nonrisk]) polymorphism were imaged at rest using both magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI). A dual-regression approach was used to investigate coactivations between the hippocampal network and other brain regions for both modalities, focusing on the theta band in the case of MEG. We found a significant decrease in intrahippocampal theta (using MEG) and greater coactivation of the superior frontal gyrus with the hippocampal network (using fMRI) in risk versus nonrisk homozygotes. Furthermore, these measures showed a significant negative correlation. Our demonstration of an inverse relationship between hippocampal theta and hippocampus-PFC coactivation supports a role for hippocampal theta in coordinating hippocampal-prefrontal activity. The ZNF804A-related differences that we find in hippocampus-PFC coactivation are consistent with previously reported associations with functional connectivity and with these changes lying downstream of altered hippocampal theta. Changes in hippocampal-PFC co-ordination, driven by differences in oscillatory activity, may be one mechanism by which ZNF804A impacts on brain function and risk for psychosis. Hum Brain Mapp, 2015. © 2015 Wiley Periodicals, Inc.Human Brain Mapping 03/2015; 36(6). DOI:10.1002/hbm.22778 · 6.92 Impact Factor
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- "However, the exact functions of ZNF804A remain unknown . Some studies suggested that rs1344706 may be associated with brain structure and function   . To further explore whether the risk allele A of rs1344706 would increase the risk of schizophrenia in different populations, the present meta-analysis was performed to evaluate the association between rs1344706 and the risk of schizophrenia in Asian, Caucasian and other populations. "
ABSTRACT: Schizophrenia is one of the most serious mental diseases found in humans. Previous studies indicated that the single nucleotide polymorphism (SNP) rs1344706 in the gene ZNF804A encoding zinc finger protein 804A was associated with schizophrenia in Caucasian population but not in Chinese Han population. However, current results are conflicting in Asian population. In the present study, a meta-analysis was performed to revisit the association between rs1344706 and the risk of schizophrenia in Asian, Caucasian and other populations. Electronic search of PubMed database identified 25 case-control studies with available genotype frequencies of rs1344706 for the meta-analysis, involving a total of 15,788 cases and 22,654 controls. A pooled odds ratio (OR) with 95% confidence interval (CI) was used to assess the association. The current meta-analysis showed an association between rs1344706 and schizophrenia in Caucasian populations (P = 0.028, OR = 1.138, 95% CI: 1.014–1.278; P= 0.004 for heterogeneity) and Asian populations (P = 0.008, OR = 1.092, 95% CI: 1.023–1.165; P= 0.001 for heterogeneity), but not in other populations (P = 0.286, OR = 1.209, 95% CI: 0.853–1.714, P = 0.120 for heterogeneity). The Egger’s test (P > 0.05) and the Begg’s test (P > 0.05) are both suggestive of the lack of publication bias for the included studies. Thus, the absence of association in other populations suggests a genetic heterogeneity in the susceptibility of schizophrenia and demonstrates the difficulties in replicating genome-wide association study findings regarding schizophrenia across different ethnic populations. To validate the association between rs1344706 and schizophrenia, further studies with larger participant populations worldwide are needed.Genomics Proteomics & Bioinformatics 12/2014; 7(6). DOI:10.1016/j.gpb.2014.10.005