This book was written during a period when the technologies of genetic
engineering were being applied to the study of animal viruses and when
the organization and function of individual virus genes were being
elucidated. This book, which uses human and animal viruses as models,
aims to under- stand the developments in molecular virology during the
last 20 years. Al- though molecular virology could also be taught by
means of bacteriophages or plant viruses, the advantage of using animal
viruses is in their ability to cause human and animal diseases as well
as to transform cells, a primary problem in medicine. For the sake of
clarity and convenience, not all the individual contributors to the
various aspects of molecular virology were cited in the text. Instead,
the reader is referred to review articles or key papers that list the
numerous excel- lent publications that have contributed to clarification
of the various molecular processes. Thus the end-of-chapter
bibliographies will guide the reader to the publications in which the
original contributing authors are quoted. References given under the
heading Recommended Reading are intended to assist those interested in
pursuing a given subject further. I hope that this book will fulfill the
purpose for which it is designed, and I urge readers to contact me if
errors are found or updating is required.