DNA methylation and its basic function.
Level 5 - mechanism / opinion, no new human data
Narrative review of biological mechanisms without original human data or systematic review methodology.
PubMed 22781841 · doi:10.1038/npp.2012.112
What was done
This review synthesizes the molecular machinery and biological roles of DNA methylation and demethylation within the mammalian nervous system. It examines interactions between DNA methylation, histone modifications, and noncoding RNAs, focusing on how postmitotic neurons maintain and modulate methylation patterns in response to physiological and environmental stimuli.
What was found
The abstract reports no quantitative data or specific numerical results. It describes qualitative biological principles: postmitotic neurons express DNA methyltransferases and demethylation components, neuronal activity alters methylation patterns dynamically, and aberrant DNA methylation caused by developmental mutations or environmental insults (such as drug exposure and neural injury) correlates with mental impairment.
Why it matters
The paper outlines how dynamic epigenetic regulation operates in non-dividing brain cells, establishing DNA methylation pathways as potential mechanistic links to cognitive dysfunction and targets for neuropsychiatric interventions.
Limits
As a narrative review, the work lacks systematic study selection criteria, quality appraisal, and meta-analytic pooling. The abstract provides no primary human experimental data, sample sizes, or quantitative effect estimates, relying instead on high-level mechanistic overview.
Cited by
- supports DNA methylation at CpG sites generally represses gene expression by rendering genomic regions inaccessible, whereas DNA demethylation is associated with active gene transcription.