Epigenome-Wide Association Studies in Psychiatry:Achievements and Problems

Genetic variation can only explain a small portion of risk to psychiatric disorders, including major depressive disorder, schizophrenia, and post-traumatic stress disorder. Epidemiological studies are increasingly showing a link between environmental factors and the development of various psychiatric disorders, mainly mediated by underlying epigenetic mechanisms. DNA methylation is one of the most studied epigenetic mechanisms in psychiatric disorders. Epigenome-wide association studies (EWAS) typically used to study changes in DNA methylation still face methodological challenges and limitations at both the fundamental, technical, and data analysis levels. In this chapter, we offer a brief overview of some EWAS studies in different psychiatric disorders and discuss the current challenges, pitfalls, and future considerations for this field