Recommended Criteria for the Evaluation of Bacterial Mutagenicity Data (Ames Test)

Publication date: Available online 5 August 2019Source: Mutation Research/Genetic Toxicology and Environmental MutagenesisAuthor(s): Dan D. Levy, Errol Zeiger, Patricia Escobar, Atsushi Hakura, Bas-jan M. van der Leede, Masayuki Kato, Martha M. Moore, Kei-ichi SugiyamaAbstractA committee was constituted within the International Workshop on Genetic Toxicology Testing (IWGT) to evaluate the current criteria for a valid Ames test and to provide recommendations for interpretation of test results. Currently, determination of a positive vs. a negative result is made by applying various data evaluation procedures for comparing dosed plates with the concurrent solvent control plates. These evaluation procedures include a requirement for a specific fold increase (2- or 3-fold, specific to the bacterial strain), formal statistical procedures, or subjective (expert judgment) evaluation. After extensive discussion, the workgroup was not able to reach consensus recommendations in favor of any of these procedures. There was a consensus that combining additional evaluation criteria to the comparison between dosed plates and the concurrent solvent control plates improves test interpretation. The workgroup recommended using these additional criteria because the induction of mutations is a continuum of responses and there is no biological relevance to a strict dividing line between a positive (mutagenic) and not-positive (nonmutagenic) response. The most useful additional criteria identified w...
Source: Mutation Research Genetic Toxicology and Environmental Mutagenesis - Category: Genetics & Stem Cells Source Type: research