1Int. J. Neuropsychopharmacol. 2009 Aug 12: 885-94
PMID19154657
TitleAssociation between golli-MBP and schizophrenia in the Jewish Ashkenazi population: are regulatory regions involved?
AbstractMultiple studies have reported oligodendrocyte and myelin abnormalities, as well as dysregulation of their related genes, in brains of schizophrenia patients. One of these genes is the myelin-basic-protein (MBP) gene, which encodes two families of proteins: classic-MBPs and golli-MBPs. While the classic-MBPs are predominantly located in the myelin sheaths of the nervous system, the golli proteins are more widely expressed and are found in both the immune and the nervous systems. In the present study we performed a case-control association analysis of golli-MBP in two separate Jewish Ashkenazi cohorts (cohort I: 120 patients, 236 controls; cohort II: 379 patients, 380 controls). In addition we performed an expression analysis of golli-MBP mRNA in post-mortem dorsolateral prefrontal cortex samples of schizophrenia patients, and matched controls. In the first cohort we observed association between six (out of 26 genotyped) single nucleotide polymorphisms (SNPs) and the disease (p<0.05). Of these, three are from one linkage disequilibrium (LD) block which contains a CTCF binding region. Haplotype analysis revealed significant 'risk'/'protective' haplotypes (strongest p=0.005, each) for schizophrenia. The three SNPs (rs12458282, rs2008323, rs721286) were then genotyped in the second cohort. The combined results showed strong effects, both in the single marker and in haplotype analyses (strongest OR 1.77, p=0.0005; OR 1.61, p=0.00001, respectively). Sequencing the CTCF binding region revealed three SNPs in complete LD with the associated haplotypes, located in close proximity to the CTCF binding site. Expression analysis found no significant differences in golli-MBP mRNA levels. These findings suggest that golli-MBP is a possible susceptibility gene for schizophrenia.
SCZ Keywordsschizophrenia
2PLoS ONE 2011 -1 6: e18455
PMID21494683
TitleGenetic and metabolic characterization of insomnia.
AbstractInsomnia is reported to chronically affect 10?15% of the adult population. However, very little is known about the genetics and metabolism of insomnia. Here we surveyed 10,038 Korean subjects whose genotypes have been previously profiled on a genome-wide scale. About 16.5% reported insomnia and displayed distinct metabolic changes reflecting an increase in insulin secretion, a higher risk of diabetes, and disrupted calcium signaling. Insomnia-associated genotypic differences were highly concentrated within genes involved in neural function. The most significant SNPs resided in ROR1 and PLCB1, genes known to be involved in bipolar disorder and schizophrenia, respectively. Putative enhancers, as indicated by the histone mark H3K4me1, were discovered within both genes near the significant SNPs. In neuronal cells, the enhancers were bound by PAX6, a neural transcription factor that is essential for central nervous system development. Open chromatin signatures were found on the enhancers in human pancreas, a tissue where PAX6 is known to play a role in insulin secretion. In PLCB1, CTCF was found to bind downstream of the enhancer and interact with PAX6, suggesting that it can probably inhibit gene activation by PAX6. PLCB4, a circadian gene that is closely located downstream of PLCB1, was identified as a candidate target gene. Hence, dysregulation of ROR1, PLCB1, or PLCB4 by PAX6 and CTCF may be one mechanism that links neural and pancreatic dysfunction not only in insomnia but also in the relevant psychiatric disorders that are accompanied with circadian rhythm disruption and metabolic syndrome.
SCZ Keywordsschizophrenia
3Epigenetics 2012 Feb 7: 155-63
PMID22395465
TitleEpigenetic and genetic variation at the IGF2/H19 imprinting control region on 11p15.5 is associated with cerebellum weight.
AbstractIGF2 is a paternally expressed imprinted gene with an important role in development and brain function. Allele-specific expression of IGF2 is regulated by DNA methylation at three differentially methylated regions (DMRs) spanning the IGF2/H19 domain on human 11p15.5. We have comprehensively assessed DNA methylation and genotype across the three DMRs and the H19 promoter using tissue from a unique collection of well-characterized and neuropathologically-dissected post-mortem human cerebellum samples (n = 106) and frontal cortex samples (n = 51). We show that DNA methylation, particularly in the vicinity of a key CTCF-binding site (CTCF3) in the imprinting control region (ICR) upstream of H19, is strongly correlated with cerebellum weight. DNA methylation at CTCF3 uniquely explains ~25% of the variance in cerebellum weight. In addition, we report that genetic variation in this ICR is strongly associated with cerebellum weight in a parental-origin specific manner, with maternally-inherited alleles associated with a 16% increase in cerebellum weight compared with paternally-inherited alleles. Given the link between structural brain abnormalities and neuropsychiatric disease, an understanding of the epigenetic and parent-of-origin specific genetic factors associated with brain morphology provides important clues about the etiology of disorders such as schizophrenia and autism.
SCZ Keywordsschizophrenia
4PLoS Genet. 2014 Jun 10: e1004345
PMID24901509
TitleIntegrated pathway-based approach identifies association between genomic regions at CTCF and CACNB2 and schizophrenia.
AbstractIn the present study, an integrated hierarchical approach was applied to: (1) identify pathways associated with susceptibility to schizophrenia; (2) detect genes that may be potentially affected in these pathways since they contain an associated polymorphism; and (3) annotate the functional consequences of such single-nucleotide polymorphisms (SNPs) in the affected genes or their regulatory regions. The Global Test was applied to detect schizophrenia-associated pathways using discovery and replication datasets comprising 5,040 and 5,082 individuals of European ancestry, respectively. Information concerning functional gene-sets was retrieved from the Kyoto Encyclopedia of Genes and Genomes, Gene Ontology, and the Molecular Signatures Database. Fourteen of the gene-sets or pathways identified in the discovery dataset were confirmed in the replication dataset. These include functional processes involved in transcriptional regulation and gene expression, synapse organization, cell adhesion, and apoptosis. For two genes, i.e. CTCF and CACNB2, evidence for association with schizophrenia was available (at the gene-level) in both the discovery study and published data from the Psychiatric Genomics Consortium schizophrenia study. Furthermore, these genes mapped to four of the 14 presently identified pathways. Several of the SNPs assigned to CTCF and CACNB2 have potential functional consequences, and a gene in close proximity to CACNB2, i.e. ARL5B, was identified as a potential gene of interest. Application of the present hierarchical approach thus allowed: (1) identification of novel biological gene-sets or pathways with potential involvement in the etiology of schizophrenia, as well as replication of these findings in an independent cohort; (2) detection of genes of interest for future follow-up studies; and (3) the highlighting of novel genes in previously reported candidate regions for schizophrenia.
SCZ Keywordsschizophrenia
5Carcinogenesis 2014 Dec 35: 2687-97
PMID25239642
TitleIdentification of chimeric TSNAX-DISC1 resulting from intergenic splicing in endometrial carcinoma through high-throughput RNA sequencing.
AbstractGene fusion is among the primary processes that generate new genes and has been well characterized as potent pathway of oncogenesis. Here, by high-throughput RNA sequencing in nine paired human endometrial carcinoma (EC) and matched non-cancerous tissues, we obtained that chimeric translin-associated factor X-disrupted-in-schizophrenia 1 (TSNAX-DISC1) occurred significantly upregulated in multiple EC samples. Experimental investigation showed that TSNAX-DISC1 appears to be formed by splicing without chromosomal rearrangement. The chimera expression inversely correlated with the binding of CCCTC-binding factor (CTCF) to the insulators. Subsequent investigations indicate that long intergenic non-coding RNA lincRNA-NR_034037, separating TSNAX from DISC1, regulates TSNAX -DISC1 production and TSNAX/DISC1 expression levels by extricating CTCF from insulators. Dysregulation of TSNAX influences steroidogenic factor-1-stimulated transcription on the StAR promoter, altering progesterone actions, implying the association with cancer. Together, these results advance our understanding of the mechanism in which lincRNA-NR_034037 regulates TSNAX-DISC1 formation programs that tightly regulate EC development.
SCZ Keywordsschizophrenia