Genetic aspects of induced mutation.

Genetic variability within the human species as well as within animal species used for mutagenicity testing may lead to misclassification of potentially mutagenic agents. Such genetic variability should be considered on three levels: uptake of the agent, its metabolism, and its action on the DNA. Testing of a possibly mutagenic agent in vitro on cells of the individuals to whom the agent is to be administered would help to avoid part of the hazard.