Induction of gene conversion in diploid yeast by chemicals: correlation with mutagenic action and its relevance in genotoxicity screening.

More than 200 chemicals, comprising drugs, pesticides, herbicides, industrial chemicals, food additives, etc. tested by various workers for their ability to induce gene conversion in diploid yeast, have been reviewed. This review shows that a strong correlation exists between the convertogenic and mutagenic abilities of these chemicals. This conclusion confirms the earlier one by Zimmermann which was based on fewer mutagenic chemicals. Published data have further been analysed to confirm quantitatively Zimmermann's other important conclusion that gene conversion is not mutagen-specific. This is a positive advantage in using gene conversion in preliminary screening of chemicals because it reduces the chances of false negatives.