DNA methylation and schizophrenia – the role in pathogenesis and the diagnosis of the disease

Objective
Schizophrenia is a neurodevelopmental disorder associated with deficits in cognition, affect, and social functioning. Despite its high heritability, there are known external risk factors, the presence of which substantially increases the likelihood of developing schizophrenia. Epigenetic modifications seem to play a key role in the multifactorial pathogenesis of the disease, linking genetic and environmental components through mechanisms that cause reversible changes in gene expression in response to specific external factors. DNA methylation is an example of such a mechanism. This work aims to review the current research regarding its potential role in the development, diagnosis, and treatment of schizophrenia.

Review of the literature
This article reviews the literature related to the issue of DNA methylation in schizophrenia. Articles in English have been selected from the PubMed database, using the following search terms: “DNA methylation,” “schizophrenia,” and “markers.” As the basis for further analysis, reviews devoted directly to epigenetic modifications, including DNA methylation, in schizophrenia, published between 2017 and 2022, were chosen from the results. A summary of the collected data is presented below.

Conclusions
Characteristic changes in the methylation pattern of specific genes appear in tissues collected from patients with schizophrenia or from corresponding animal models. The goal of further research should be to create a database of specific DNA methylation patterns, the presence of which could act as a biomarker or an indicator of the effectiveness of a therapeutic process. It is crucial to standardise the genome methylation analysis system and to validate other tissues to be used as substitutes for the brain tissue.