An approach for evaluating and increasing the informational content of mutagenicity and clastogenicity data bases.

A method is described for using the fragments identified by the CASE structure-activity relational expert system to identify the type of chemicals that require further testing in mutagenicity and clastogenicity assays. Inclusion of such chemicals will increase the informational content of databases with respect to structural features that are under-represented in currently available data bases. The method is applied to existing databases (mutagenicity in Salmonella, chromosomal aberrations in Chinese hamster ovary cells, unscheduled DNA synthesis in rat hepatocytes, in vivo induction of micronuclei, somatic mutations in Drosophila melanogaster) to identify structural determinants that are absent.