It is well established that major psychosis (schizophrenia and bipolar disorder) has a strong hereditary basis. However, no unequivocal genetic mutation or polymorphism underlying these disorders has been identified thus far. This paper discusses the role of epigenetics (heritable changes in gene expression not involving changes in DNA sequence) in the pathogenesis of the major psychoses. Importantly, epigenetics offers a conceptual interface between the environment and the genome in the pathogenesis of these disorders. The paper discusses the epigenetically modified genes that are thought to predispose to the development of the major psychoses. The putative environmental factors that can epigenetically modify the genes underlying these disorders are also presented. Finally, the paper offers a framework for epigenetics research applications with considerations over diagnosis, treatment, and prevention of these disorders that have a substantial public health burden throughout the world including the Asia-Pacific region.
Keywords: Disease risk, epigenetics, epigenome, methylation, personalized medicine, psychiatry, psychosis, variability