GENETICALLY-MODIFIED CHINESE-HAMSTER OVARY (CHO) CELLS FOR STUDYING THE GENOTOXICITY OF HETEROCYCLIC AMINES FROM COOKED FOODS

We have developed metabolically competent Chinese hamster ovary (CHO) cells to evaluate the genotoxicity associated with heterocyclic amines , such as those that are present in cooked foods. Into repair-deficien t UV5 cells we introduced cDNAs for expressing cytochrome P450IA2 and acetyltransferases. We then genetically reverted these transformed lin es to obtain matched metabolically competent repair-deficient/proficie nt lines. For a high mutagenic response, we find a requirement for ace tyltransferase with 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) but n ot with 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). This s ystem allows for both quantifying mutagenesis and analyzing the mutati onal spectra produced by heterocyclic amines.