A brief history of Drosophila's contributions to genome research

The sequence of the Drosophila melanogaster genome presented in this issue of Science is the latest milestone in nine decades of research on this orga nism. Genetic and physical mapping, whole-genome mutational screens, and fu nctional alteration of the genome by gene transfer were pioneered in metazo ans with the use of this small fruit fly. Here we Look at some of the insta nces in which work on Drosophila has Led to major conceptual or technical b reakthroughs in our understanding of animal genomes.