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Bacterial Reverse Mutation Test (Ames, OECD 471)
The Ames test assesses the mutagenic potential of a compound — the first-line screen for genotoxic, mutation-inducing activity through DNA base-pair substitution, addition or deletion.
What's inside
- Principle of the bacterial reverse mutation (Ames) test
- Salmonella typhimurium tester strains and histidine reversion
- Detection of base substitution and frameshift mutations
- Regulatory context: OECD 471 and ICH guidelines
The Bacterial Reverse Mutation test (Ames) assesses the mutagenic potential of a compound and is commonly employed as an initial screen for genotoxic activity — in particular for mutation-inducing activity involving the substitution, addition or deletion of DNA base pairs.
Ames testing uses several strains of Salmonella typhimurium carrying a defective (mutant) gene that renders them unable to synthesise the amino acid histidine. The test investigates the potential of the compound to cause a back mutation that restores the bacteria’s ability to synthesise histidine, allowing growth on a histidine-deficient medium.
Who this is for
- Pharmaceutical and biotech genotoxicity teams
- Cosmetic and food ingredient safety assessors
- Regulatory affairs requiring OECD 471 data
Recommended citation
GenEvolutioN Scientific Team (2025). Bacterial Reverse Mutation Test (Ames, OECD 471). GenEvolutioN Technologies.