of molecular and cell biological tools to analyze the genome of an oncogenic virus. 1977 for his contributions to the understanding of eukaryotic, viral, and cellular messenger RNAs. 1978 Günter Blobel for elucidating mechanisms of passage of secreted proteins into and across membranes. 1979 Mark Ptashne for his outstanding contributions to our understanding of gene regulation through the studies of the virus Lambda. 1980 Phillip A. Sharp for his pioneering and continuing contributions to our understanding of messenger RNA biogenesis in mammalian cells. 1981 Ronald W. Davis and Gerald Fink for their outstanding contributions to the molecular biology of the simple eukaryote Saccharomyces cerevisiae. Both have opened vistas of genetic analysis by the development of new methods, in particular, the development and utilization of molecular cloning in yeast. 1982 Joan A. Steitz for contributing to our understanding of how RNA molecules are recognized by enzymes and discovering the roles played by small ribonucleoprotein molecules in RNA processing. 1983 James C. Wang for his ingenious studies of the topological properties of the DNA double helix and his discovery of the important class of enzymes known as DNA topoisomerases. 1984 Geoffrey M. Cooper and Robert A. Weinberg for the identification and characterization of cellular oncogenes of human and animal tumors, thereby providing seminal insights into the mechanisms of carcinogenesis. 1985 Gerald M. Rubin and Allan C. Spradling for adding a new dimension to eukaryotic genetics and developmental biology by developing a method to introduce and stably integrate cloned genes into the germ cells of living Drosophila. 1986 Robert G. Roeder for his pioneering studies of eukaryotic RNA polymerases and the factors that regulate their activity. 1987 Thomas R. Cech for the astonishing discovery of RNA-catalyzed self-splicing of introns and the analysis of the chemistry of RNA-catalyzed reactions. 1988 H. Robert Horvitz for significant contributions to the genetic analysis of the development of cell lineages in the nematode Caenorhabditis elegans. 1989 Kiyoshi Mizuuchi for bringing about remarkable advances in our understanding of transposition and other forms of genetic recombination. 1990 Elizabeth H. Blackburn for her discovery of the nature of DNA at the ends of eukaryotic chromosomes and the enzyme that is necessary to complete chromosomal replication. 1991 Steven McKnight and Robert Tjian for advancing our understanding of transcriptional regulation by devising novel strategies and applying elegant biochemistry to reveal fundamental mechanisms underlying gene expression and development. 1992 Bruce S. Baker and for