With the advent of genetic engineering methods and improved biochemical tech­ niques, much has been learned about the replication of influenza viruses, their structure and their epidemiology. It appears that the time is ripe to review these efforts and to provide a molecular perspective of influenza virology. It is hoped that this book will stimulate our thinking, help us in designing new experiments, and possibly show avenues leading to the control of the diseases associated with influenza viruses. Peter Palese, New York, N. Y. August 1983 David W. Kingsbury, Memphis, Tenn. Contents List of Contributors. . . . . . . . . . . . . . . . . XV 1. The Evolution of Influenza Viral Genetics - A Perspective. By E. D. Kilbourne. . . . . . . . . . . . . . . . 1 I. Introduction. . . . . . . . . . . . . . . . . 1 II. The Development of Modern Influenza Viral Genetics 2 A. Early Evidence of Genetic Variation in the Laboratory 2 B. Application of Formal Genetic Techniques to Studies of Influenza Virus . . . . . . . 3 C. Genetic Markers. . . . . . . . . 3 D. Development of Plaquing Systems. . . 4 E. The Use of Conditional Lethal Mutants 5 F. New Approaches in Influenza Virus Genetics. 6 1. The Biochemical Identification of Viral Gene Products in the Unambiguous Definition of Viral Inheritance . . . 6 2. Mapping of the Influenza Virus Genome by Correlative Physico-Chemical and Biological Techniques. . . . . . 7 3. The Application of Molecular Biological Techniques to the Study of Viral Genetic Variation. . . . . . . . . 8 4. Oligonucleotide Mapping of Viral RNA's . . . . . . . 8 5. Contribution of Protein and RNA Sequencing to Influenza Viral Genetics-Intragenic Mapping . . . . . . . 8 III. Viral Genetics and the Understanding of Viral Virulence and Pathogenicity . . . . . . . . . . .. . . . . . . .