Large-scale mutagenesis: yeast genetics in the genome era

The completion of the DNA sequence of the budding yeast Saccharomyces cerev isiae resulted in the identification of a large number of genes. However, t he function of most of these genes is not known. One of the best ways to de termine gene function is to carry out mutational and phenotypic analysis. I n recent years, several approaches have been developed for the mutational a nalysis of yeast genes on a large scale. These include transposon-based ins ertional mutagenesis, and systematic deletions using PCR-based approaches. These projects have produced collections of yeast strains and plasmid allel es that can be screened using novel approaches. Analysis of these collectio ns by the scientific community promises to reveal a great deal of biologica l information about this organism.