New genetic strategies for protein discovery based on whole-genome sequences

Determining the genomic sequences of the most commonly used model organisms has led to a new era in genetic studies. Each predicted gene of a sequenced organism can now be inactivated to create collections of all possible loss-of-function mutants. Whole-genome mutant collections are now available for the yeast Saccharomyces cerevisiae, and reagents are available to inactivate every gene in the roundworm Caenorhabditis elegans. This article describes how these collections have stimulated the development of novel genetic screening methods that have accelerated the pace of genetic research.