by Carsten Carlberg, Ferdinand Molnár

The term epigenetics describes regulatory and information storing mechanisms of specific genes that do not involve any change of their DNA sequence. Epigenetics is closely related to the extensively folded state, in which the genome is packaged, known as chromatin. New genomic tools nowadays allow the genome-wide assessment of, for example, chromatin states and DNA modifications, and led to the discovery of unexpected new epigenetic principles, such as epigenomic memory. This was the start of the field of epigenomics, the relation of which to human health and disease is discussed in this textbook.

This book aims to summarize, in a condensed form, the role of epigenomics in defining chromatin states that are representative of active genes (euchromatin) and repressed genes (heterochromatin). Moreover, this book discusses the principles of gene regulation, chromatin stability, genomic imprinting and the reversibility of DNA methylation and histone modifications. This information should enable a better understanding of cell type identities and will provide new directions for studies of, for example, cellular reprograming, the response of chromatin to environmental signals and epigenetic therapies that can improve or restore human health. In order to facilitate the latter, we favor a high figure-to-text ratio following the rule “a picture tells more than thousand words”.