Project description:Suicide is the second leading cause of death globally among young people representing a significant global health burden. Although the molecular pathology of suicide remains poorly understood, it has been hypothesised that epigenomic processes may play a role. The objective of this study was to identify suicide-associated DNA methylation changes in the human brain by utilising previously published and unpublished methylomic datasets. We analyzed prefrontal cortex (PFC, n = 211) and cerebellum (CER, n = 114) DNA methylation profiles from suicide completers and non-psychiatric, sudden-death controls, meta-analyzing data from independent cohorts for each brain region separately. We report evidence for altered DNA methylation at several genetic loci in suicide cases compared to controls in both brain regions with suicide-associated differentially methylated positions enriched among functional pathways relevant to neuropsychiatric phenotypes and suicidality, including nervous system development (PFC) and regulation of long-term synaptic depression (CER). In addition, we examined the functional consequences of variable DNA methylation within a PFC suicide-associated differentially methylated region (PSORS1C3 DMR) using a dual luciferase assay and examined expression of nearby genes. DNA methylation within this region was associated with decreased expression of firefly luciferase but was not associated with expression of nearby genes, PSORS1C3 and POU5F1. Our data suggest that suicide is associated with DNA methylation, offering novel insights into the molecular pathology associated with suicidality. DNA from bulk post-mortem brain (human cerebellum) from 33 individuals
Project description:Suicide is the second leading cause of death globally among young people representing a significant global health burden. Although the molecular pathology of suicide remains poorly understood, it has been hypothesised that epigenomic processes may play a role. The objective of this study was to identify suicide-associated DNA methylation changes in the human brain by utilising previously published and unpublished methylomic datasets. We analyzed prefrontal cortex (PFC, n = 211) and cerebellum (CER, n = 114) DNA methylation profiles from suicide completers and non-psychiatric, sudden-death controls, meta-analyzing data from independent cohorts for each brain region separately. We report evidence for altered DNA methylation at several genetic loci in suicide cases compared to controls in both brain regions with suicide-associated differentially methylated positions enriched among functional pathways relevant to neuropsychiatric phenotypes and suicidality, including nervous system development (PFC) and regulation of long-term synaptic depression (CER). In addition, we examined the functional consequences of variable DNA methylation within a PFC suicide-associated differentially methylated region (PSORS1C3 DMR) using a dual luciferase assay and examined expression of nearby genes. DNA methylation within this region was associated with decreased expression of firefly luciferase but was not associated with expression of nearby genes, PSORS1C3 and POU5F1. Our data suggest that suicide is associated with DNA methylation, offering novel insights into the molecular pathology associated with suicidality. DNA from bulk post-mortem brain (human cerebellum) from 58 individuals
Project description:Systematic meta-analysis and replication of genome-wide expression studies identifies molecular pathways of Parkinson's disease. Examination of substantia nigra from postmortem brains of 8 patients with Parkinson's disease (PD).
Project description:We compared the genome-wide patterns of DNA methylation in the brains of humans to those of our closest evolutionary relative, chimpanzees, using base-pair resolution whole-genome methylation maps of the prefrontal cortex. Our data reveal that the prefrontal cortex is the most heavily methylated among the human tissues examined so far. Nevertheless, hundreds of genes exhibit dramatically reduced levels of promoter DNA methylation in the human brain relative to the chimpanzee brain. Many of these genes are associated with neurological disorders, psychological disorders, and cancers, and are enriched for functions related to cellular metabolic processes and protein binding. Moreover, the majority of these genes exhibit higher expression in the human brain compared to the chimpanzee brain. Profiling DNA methylation map in prefrontal cortex regions of postmortem brains of three humans and three chimpanzees
Project description:Systematic meta-analysis and replication of genome-wide expression studies identifies molecular pathways of Parkinson's disease. Analysis of substantia nigrae from postmortem brains of 6 patients with Parkinson's disease (PD). Results provide insight into the molecular processes perturbed in the PD substantia nigra.
Project description:We compared the genome-wide patterns of DNA methylation in the brains of humans to those of our closest evolutionary relative, chimpanzees, using base-pair resolution whole-genome methylation maps of the prefrontal cortex. Our data reveal that the prefrontal cortex is the most heavily methylated among the human tissues examined so far. Nevertheless, hundreds of genes exhibit dramatically reduced levels of promoter DNA methylation in the human brain relative to the chimpanzee brain. Many of these genes are associated with neurological disorders, psychological disorders, and cancers, and are enriched for functions related to cellular metabolic processes and protein binding. Moreover, the majority of these genes exhibit higher expression in the human brain compared to the chimpanzee brain.