Schizophrenia: An epigenetic puzzle?

Developments in molecular biology over the past three decades have led to a n increasing awareness of the importance of epigenetic phenomena in a varie ty of genome functions. Epigenetic aspects of complex multifactorial diseas es including schizophrenia, however, have not been investigated sufficientl y. Various facets of epigenetics are reevaluated through their putative rel evance to four theories of schizophrenia: neurodevelopmental, dopamine dysf unction, viral, and genetic anticipation with unstable DNA. The heuristic v alue of the epigenetic model of schizophrenia arises from the possibility o f integration of a wide variety of empirical data into a new theoretical fr amework. It can be hypothesized that in addition to pathological effects of DNA structural mutations and environmental factors, inherited and acquired epigenetic defects, or epimutations, may be of etiological importance in s chizophrenia. In addition, the epigenetic model may lead to experiments inv estigating the molecular substrates of genetic-environmental interactions.