Project description:Methylomic studies require substantial amounts of DNA samples and this restriction hinders applications involving scarce animal or patient samples with direct biomedical relevance. Here we report a microfluidics-based reduced representative bisulfite sequencing protocol, MIcrofluidic Diffusion-based RRBS (MID-RRBS), that permits methylomic profiling with sub-1 ng starting DNA. Using this technology, we studied DNA methylation in NeuN+ and NeuN- fractions isolated from mouse cerebellum, revealing cell-type specific methylomic patterns. We also studied the DNA methylation in NeuN+ nuclei isolated from clozapine or vehicle treated mouse frontal cortex.
Project description:Background: Schizophrenia is a severe neuropsychiatric disorder that is hypothesized to result from disturbances in early brain development, and there is mounting evidence to support a role for developmentally-regulated epigenetic variation in the molecular etiology of the disorder. Here, we describe a systematic study of schizophrenia-associated methylomic variation in the adult brain and its relationship to changes in DNA methylation across human fetal brain development. Results: We profile methylomic variation in matched prefrontal cortex and cerebellum brain tissue from schizophrenia patients and controls, identifying disease-associated differential DNA methylation at multiple loci, particularly in the prefrontal cortex, and confirming these differences in an independent set of adult brain samples. Our data reveal discrete modules of co-methylated loci associated with schizophrenia that are enriched for genes involved in neurodevelopmental processes and include loci implicated by genetic studies of the disorder. Methylomic data from human fetal cortex samples, spanning 23 to 184 days post-conception, indicates that disease-associated differentially methylated positions are significantly enriched for loci at which DNA methylation is dynamically altered during human fetal brain development. Conclusions: Our data support the hypothesis that schizophrenia has an important early neurodevelopmental component, and suggest that epigenetic mechanisms may mediate these effects. 33 post-mortem brain (prefrontal cortex) samples (18 schizophrenia cases and 15 controls) were obtained from Douglas Bell-Canada Brain Bank (DBCBB), Montreal, Canada. Bisulfite converted DNA from these samples were hybridised to the Illumina Infinium 450k Human Methylation Beadchip v1.0.
Project description:Reduced representation bisulfite sequencing (RRBS) was conducted on dorsolateral prefrontal cortex tissue samples taken from the brains of control individuals not affected by neurological disorder DNA methylation profiling was conducted using RRBS and the Illumina Genome Analyzer IIx