ABSTRACT
Reverse genetics is a powerful tool to elucidate gene functions and to contribute, for example, to the elucidation of the function of many genes revealed by sequencing the genome of a model organism. This gene function discovery is generally done by altering the expression or by disrupting the gene under study. Several methodologies are used to carry out these reverse genetic studies. In both yeast, Saccharomyces cerevisiae, and the mouse, homologous recombination can be used specifically to delete genes of interest and to analyze the effect of the mutation on growth and development. This approach has been successfully used to identify essential genes in S. cerevisiae (Ross-Macdonald et al., 1999; Lucau-Danila et al., 2000) and similar programs have been initiated in the case of the mouse (Zambrowicz et al., 1998). In the worm Caenorhabditis elegans, RNAi technology was applied to inactivate all single genes of this organism (Kamath et al., 2001). Thus, reverse genetics is complementary and may be as important as genome sequencing for the molecular identification of biological functions.
