Epigenetics and the personalized treatment of anxiety disorders

Anxiety disorders are to be treated with cognitive behavioral therapy and serotonergic antidepressants. Clinical aspects are to be taken into account in an individualized approach. To further develop personalized, biomarker-based treatments neuroscience research has focused on brain imaging, laboratory markers, genetics and epigenetics. The current review focuses on research on how epigenetic variation affects therapy outcome. It summarizes the literature which comprises 12 studies focusing on the role of DNA methylation with few replicated findings between studies. Results are summarized and interpreted in context with genetic findings. Methodological limitations of epigenetic studies are discussed. First, cohort sizes are small compared to those used in genetic studies. Second, preanalytical procedures are of particular importance in epigenetic research because of the inherent instability of DNA methylation; generally accepted standard protocols are currently lacking. Third, the transferability of blood methylation status to brain or liver has to be addressed in interpretation of the results. Solutions to address these methodological challenges are discussed focusing on a synergistic approach with genetic studies. The development of a consensus on standards of epigenetic methodology will be essential to allow the realization of its potential for a personalized treatment of anxiety disorders.