L4 - Mutational signatures Flashcards
AMES test: what is it, how does it work, and what are the positives?
Used to assess the potential carcinogenic effect of chemicals by using the bacterial strain Salmonella typhimurium
Mix a compound with homogenised rat liver (allows metabolites to be formed) and grow it on bacteria - by counting the amount of bacterial mutations, a mutagenic score is formed
- Quick and inexpensive
- High-throughput
- Uses well-established model organism
- Salmonella typhimurium,
- Simple to perform
- Reliable
- Non-animal
AMES test: what are the drawbacks to the test?
Limited predictive power: indicate whether a chemical is mutagenic, it cannot predict toxicity or the specific types of mutations that may occur in humans.
May not detect all mutagens: The test only screens for mutagens that cause frameshift mutations.
May not detect all mutagens: Some chemicals that are mutagenic in higher organisms may not cause mutations in the bacteria
May give false positives: Some chemicals that are not mutagenic in higher organisms may cause mutations in the bacteria
May not detect all mutagens: anything toxic and kills bacteria is not assessed for mutagenicity