Project description:Background: Autism spectrum disorder (ASD) is a severe early onset neurodevelopmental disorder with high heritability but significant heterogeneity. Traditional genome-wide approaches to test for association of common variants with autism susceptibility risk has met with limited success. However, novel methods to identify moderate risk alleles in attainable sample sizes are now gaining momentum. Methods:M-BM- In this study, we utilized publically available GWAS data from the Autism Genome Project (AGP) and annotated the results (p < 0.001) for eQTLs present in the parietal lobe, cerebellum, and lymphoblastoid cell lines. We then performed a test of enrichment by comparing these results to simulated data conditioned on minor allele frequency in order to generate an empirical p-value indicating statistically significant enrichment of eQTLs in top results from the autism GWAS. Results:M-BM- Our findings show a global enrichment of brain eQTLs, but not LCL eQTLs, among top SNPs from an autism GWAS. Additionally, the data implicates individual genesM-BM- SLC25A12,M-BM- PANX1M-BM- andM-BM- PANX2, as well as pathways previously implicated in autism. Conclusions:M-BM- These findings provide supportive rationale for the use of annotation-based approaches to GWAS. We use microarray technology to understand the etiology and pathology of psychiatric diseases at the transcriptomic level. Postmortem human brain samples came from the Stanley Medical Research InstituteM-bM-^@M-^Ys Neuropathology Consortium and Array collections, including schizophrenia, bipolar disorder and control samples.
Project description:Schizophrenia (SCZ) and bipolar disorder (BD) are highly heritable psychiatric disorders. Associated genetic and gene expression changes have been identified, but many have not been replicated and have unknown functions. We identified groups of genes whose expressions varied together, that is co-expression modules, then tested them for association with SCZ. Using weighted gene co-expression network analysis, we show that two modules were differentially expressed in patients versus controls. One, upregulated in cerebral cortex, was enriched with neuron differentiation and neuron development genes, as well as disease genome-wide association study genetic signals; the second, altered in cerebral cortex and cerebellum, was enriched with genes involved in neuron protection functions. The findings were preserved in five expression data sets, including sets from three brain regions, from a different microarray platform, and from BD patients. From those observations, we propose neuron differentiation and development pathways may be involved in etiologies of both SCZ and BD, and neuron protection function participates in pathological process of the diseases.
Project description:We used microarray expression profiling to assess protein-coding and non-coding gene expression across 8 brain samples and 7 other human tissues. We measured commercial human cDNA samples from 15 tissues: cerebellum, brain stem, frontal cortex, occipital cortex, parietal cortex, fetal brain, whole adult brain, colon, heart, kidney, liver, lung, breast and adrenal gland
Project description:The familial or genetic Creutzfeldt-Jakob disease (fCJD or gCJD) is the inherent form of human prion diseases, which accounts for approximately 10-15% of human prion diseases that are caused by mutations of the prion protein gene (PRNP). In this study, the global expression patterns of the parietal cortex from a patient with G114V gCJD were comparatively analyzed with the normal controls by using a commercial human genome expression chip. Totally 8774 genes showed differential expression, among them 2769 genes were upregulated and 6005 ones were downregulated. The reliability of the results was confirmed by the real-time RT-PCR assays for several specific genes. The most differentially expressed genes involved in the functions of regulation of transcription, ion transport, transcription, cell adhesion, signal transduction. The gene associated with gliosis was upregulated and the genes marked for neurons were downregulated, while the transcription of PRNP gene maintained unchanged. 169 different pathways showed significantly changed in the brain of G114V gCJD. The most significantly regulated pathways included that of Alzheimer’s and Parkinson’s disease, oxidative phosphorylation, regulation of actin cytoskeleton, MAPK signaling pathway and proteasome, which were described in prion diseases previously. In addition, some rarely addressed pathways in prion diseases, such as axon guidance, gap junction and purine metabolism, were also significantly changed in G114V gCJD. The transcriptional situations of the most genes in the top ten changed pathways were down-regulated. The extensive reductions of gene expressions in G114V gCJD showed the comparable profiles with sporadic CJD. The data here raised the useful clues for understanding the pathogenesis of the disease and selecting the potential biomarkers for diagnostic and therapeutic tools. Brain tissues of parietal cortex from a definitely diagnosed G114V gCJD were enrolled into this study. The patient was a 47-year-old Han-Chinese woman at the onset. Neuropathological assays of ten different brain regions revealed typical sCJD-like abnormality and PrPSc deposits. Meanwhile, a commercial normal human parietal cortex total RNA (Clontech) pooled from four male/female aged 35-89 was utilized as control.
Project description:Post mortem human brain tissue comparison between HD patients and controls from 3 brain regions - cerebellum, frontal cortex [BA4, BA9] and caudate nucleus. Gene expression analysed using linear models from LIMMA package in Bioconductor suite. Keywords: disease state analysis
Project description:Schizophrenia (SCZ) and bipolar disorder (BD) are highly heritable psychiatric disorders. Associated genetic and gene expression changes have been identified, but many have not been replicated and have unknown functions. We identified groups of genes whose expressions varied together, that is co-expression modules, then tested them for association with SCZ. Using weighted gene co-expression network analysis, we show that two modules were differentially expressed in patients versus controls. One, upregulated in cerebral cortex, was enriched with neuron differentiation and neuron development genes, as well as disease genome-wide association study genetic signals; the second, altered in cerebral cortex and cerebellum, was enriched with genes involved in neuron protection functions. The findings were preserved in five expression data sets, including sets from three brain regions, from a different microarray platform, and from BD patients. From those observations, we propose neuron differentiation and development pathways may be involved in etiologies of both SCZ and BD, and neuron protection function participates in pathological process of the diseases.
Project description:Background: Autism spectrum disorder (ASD) is a severe early onset neurodevelopmental disorder with high heritability but significant heterogeneity. Traditional genome-wide approaches to test for association of common variants with autism susceptibility risk has met with limited success. However, novel methods to identify moderate risk alleles in attainable sample sizes are now gaining momentum. Methods:M-BM- In this study, we utilized publically available GWAS data from the Autism Genome Project (AGP) and annotated the results (p < 0.001) for eQTLs present in the parietal lobe, cerebellum, and lymphoblastoid cell lines. We then performed a test of enrichment by comparing these results to simulated data conditioned on minor allele frequency in order to generate an empirical p-value indicating statistically significant enrichment of eQTLs in top results from the autism GWAS. Results:M-BM- Our findings show a global enrichment of brain eQTLs, but not LCL eQTLs, among top SNPs from an autism GWAS. Additionally, the data implicates individual genesM-BM- SLC25A12,M-BM- PANX1M-BM- andM-BM- PANX2, as well as pathways previously implicated in autism. Conclusions:M-BM- These findings provide supportive rationale for the use of annotation-based approaches to GWAS. We use microarray technology to understand the etiology and pathology of psychiatric diseases at the transcriptomic level. Postmortem human brain samples came from the Stanley Medical Research InstituteM-bM-^@M-^Ys Neuropathology Consortium and Array collections, including schizophrenia, bipolar disorder and control samples.
Project description:Ion channel splice array data from cerebellum brain tissue samples collected from Alzheimer's disease patients. Temporal cortex (Alzheimer's disease affected brain tissue structure) and cerebellum (Alzheimer's disease unaffected brain tissue structure) samples from control subjects were compared to temporal cortex and cerebellum of patients with Alzheimer's disease.