Epigenetics of Neurodevelopmental Disorders

Epigenetics is the way that the environment affects the way genes work. DNA is the basis of inheritance, but DNA does not have a function of its own. Epigenetic mechanisms determine how DNA is packaged in the nucleus, how available DNA is to be transcribed into RNA and proteins, and how the food that you eat and the air that you breathe alter your genetic destiny. Epigenetics are widely believed to contribute to neurodevelopmental disorders. Strong genetic evidence indicates that genes involved in making DNA available, called chromatin regulators, are often mutated in individuals with neurodevelopmental disorders. However, there are challenges to directly studying epigenetic mechanisms. Foremost, epigenetic mechanisms are specific to individual cells at precise time points in development. Because the human brain during neurodevelopment is inaccessible, epigenetic mechanisms must be studied in a variety of proxies. Convergence of evidence in animal models, postmortem human brains, and non-brain human tissues can indicate the mechanisms underlying neurodevelopmental disorders. The study of epigenetics in neurodevelopmental disorders is in its infancy, but important clues are beginning to emerge.