06 Mar 20. Featured Paper
DNA methylation & brain structure & function across the life course: a systematic review.
We identified 60 studies that report associations between DNA methylation (DNAm) & human brain structure/function.
Forty-three studies measured candidate loci DNAm; seventeen measured epigenome-wide DNAm.
The studies report DNAm-MRI associations for: neurodevelopment & neurodevelopmental disorders; major depression & suicidality; alcohol use disorder; schizophrenia & psychosis; ageing, stroke, ataxia & neurodegeneration; post-traumatic stress disorder; & socio-emotional processing.
Consistency between MRI features & differential DNAm is modest.
Sources of bias: variable inclusion of comparator groups; different surrogate tissues used; variation in DNAm measurement methods; lack of control for genotype & cell-type composition; & variations in image processing.
Knowledge of MRI features associated with differential DNAm may improve understanding of the role of DNAm in brain health & disease, but caution is required because conventions for linking DNAm & MRI data are not established, & clinical & methodological heterogeneity in existing literature is substantial.