Revealing the biological basis of mental illness: epigenetic research as a new direction in diagnosis and treatment

Abstract

Summary. Mental disorders are clinically heterogeneous chronic diseases resulting from complex interactions between genotype variants and environmental factors. Epigenetic processes, such as DNA methylation and post-translational histone modification, determine the interpretation by the body at the cellular and tissue levels of various environmental factors. Given that epigenetic modifications are environmentally sensitive, stable and reversible, epigenetic research in psychiatry may be a promising approach to better understanding and treating mental illness. This review discusses the clinical opportunities and challenges posed by epigenetic research in psychiatry. Using individual examples, the main conclusions are drawn that confirm the role of adverse life events, alone or in combination with genetic risk, in the epigenetic programming of neuropsychiatric systems. Further epigenetic studies show encouraging results in the use of methylation changes as diagnostic markers of disease manifestations and provide predictive tools for assessing progression and response to treatment. The potential for the use of targeted epigenetic pharmacotherapy, combined with psychosocial methods, in the context of the personalized medicine of the future in psychiatry is discussed next. It concludes with a discussion of methodological limitations that can make it difficult to interpret epigenetic data in psychiatry. They mainly arise due to the heterogeneity of individuals, both at the level of the whole organism and at the level of tissues, and require new strategies to better assess the biological significance of epigenetic data and their translational use in psychiatry. Overall, we believe that epigenetics can provide new insights and a more comprehensive understanding of the etiology and pathogenesis of mental illness, and should ultimately improve the nosology, treatment and prevention of mental disorders.

Keywords

• biological psychiatry
• biomarkers
• epigenetics
• pharmacotherapy
• psychosocial therapy