Preface

Recent advances in the fields of genomics and bioinformatics are evidencing the fact that genetic sequence alone can not explain how the genome regulates the development and function of complex multicellular organisms both in health and disease. The crucial role of additional layers of information piled over that of the DNA sequence has taken centre stage in the last few years and thus, decades of intensive studies on genetics have led to the emergence of epigenetics. Epigenetics comprises a number of mechanisms, such as covalent histone modifications or DNA methylation, which induce long-lasting changes in gene expression that are not encoded in the DNA sequence itself.

Epigenetics then reflects the way in which the environment in the wide sense regulates gene expression. In fact, it is becoming increasingly clear that the well-known beneficial role of a healthy lifestyle over a number of pathologies or as a pre-emptive therapy is at least in part exerted through epigenetic mechanisms. Likewise, changes in chromatin structure may lie beneath some of the altered behavioral patterns usually associated with depression and addiction.

The current research on epigenetics is thus providing us with a fresh outlook to interpret genetic information. Fascinating new data suggest that we are a product of our genes but we can also influence them through our choices and experiences. When designing this book, our main intention has been to provide a comprehensive view of how lifestyle affects chromatin and, as a result, gene function and ultimately organismal fitness. The chapters of this book have been written by eminent scientists actively working in the fields they review. Following an introductory chapter in which the main concepts and background regarding epigenetics are discussed, there are chapters devoted to describe the epigenetic impact of nutrition, stress, addiction, exposure to chemicals and pollutants and how some of these epigenetic marks regulate brain functions such as learning and memory. In summary, our intention is to approach epigenetics from a fresh perspective and present the reader with the latest and most significant research in the field of epigenetics and lifestyle.