Preface/Front Matter

Abstract

The study of epigenetics is almost as old as the study of genetics, although epigenetic phenomena were often not recognized for what they were. Indeed, it has usually been through the genetic manipulation of epigenetic phenomena that some understanding has been achieved: Position-effect variegation in Drosophila and mutable loci in maize were first described more than 60 years ago, and these systems provided some of the earliest clues as to the nature of epigenetic mechanisms of gene regulation.

The study of plant, mammalian, insect, fungal, and microbial epigenetics has for the most part been carried out by different groups that go to different meetings, publish in different journals, and often have a different focus. The plan for this book was to collect for the first time under one cover reviews on the epigenetics of microorganisms as well as higher organisms. The chapters of this book have been organized into several divisions. Some chapters are intended to provide historical insights, and toward this purpose three early papers on epigenetic mechanisms are reprinted at the end of the volume. Consideration was given to making other main divisions along organismic lines, such as plants, animals, and microorganisms. However, since one intent of this book is to lessen the barriers of communication between workers studying various organisms, we decided that this purpose would be better served by attempting to categorize the chapters according to function and mechanisms. It will be seen that the divisions are in many cases rather arbitrary, but we hope the