Dealing with damage

In the June 25 Proceedings of the National Academy of Sciences, Birrell et al. describe a study designed to test whether genes that are induced by DNA damage are important for survival to that damage (Proc Natl Acad Sci USA 2002, 99:8778-8783). They used a collection of yeast strains generated by the Saccharomyces Genome Deletion Project in which each gene has been replaced by a molecular 'bar code tag'. This approach has been used to identify genes involved in the response to ultraviolet (UV) radiation. Birrell et al.tested the effects of UV radiation, ionizing radiation, hydrogen peroxide and cisplatin. There was considerable overlap in the set of deletion strains that were sensitive to the different treatments. They performed microarray analysis under the same treatments and compared the results with the cytotoxicity assays. They found no correlation between induced gene expression and genes required for survival.