Antimutator mutations reduce spontaneous (and sometimes induced) mutation rates and are therefore of interest both for understanding mechanisms of spontaneous mutation and for finding ways to reduce mutation rates generally, and thus to reduce the incidence of diseases of mutational origin. We long ago discovered several antimutator alleles among temperature-sensitive mutations in the DNA polymerase gene of bacteriophage T4. These antimutators strongly reduced mutation rates along certain pathways, such as A:T to G:C, but were then found to have little effect on other pathways and even to act as mutator mutations on yet other pathways. We therefore initiated a search for generalized DNA polymerase antimutator mutations, defined as mutations that reduce mutation rates measured in a large target representative of the genome as a whole. None were found and this project is completed.
