Abstract
Psychiatric diseases place a tremendous burden on affected individuals, their caregivers, and the health care system. Although evidence exists for a strong inherited component to many of these conditions, dedicated efforts to identify DNA sequence-based causes have not been exceptionally productive, and very few pharmacologic treatment options are clinically available. Many features of psychiatric diseases are consistent with an epigenetic dysregulation, such as discordance of monozygotic twins, late age of onset, parent-of-origin and sex effects, and fluctuating disease course. In recent years, experimental technologies have significantly advanced, permitting in-depth studies of the epigenome and its role in maintenance of normal genomic functions, as well as disease etiopathogenesis. Here, we present an epigenetic explanation for many characteristics of psychiatric disease, review the current literature on the epigenetic mechanisms involved in major psychosis, Alzheimer's disease, and autism spectrum disorders, and describe some future directions in the field of psychiatric epigenomics.