Heritable translocation test in mice

The status of the heritable-translocation test in mice with respect to its usefulness in practical testing was evaluated by using information available in the open literature. A total of 47 reports were evaluated; 29 were judged to contain adequate information to classify whether or not a given chemical induced heritable translocations. Heritable-translocation data were available for 32 compounds; data were not adequate for 15 compounds. Of the remaining 17 compounds, clear-cut determination of positive or negative effects was made for 14 compounds, while data for 3 compounds were only suggestive of either negative or positive effects. 10 chemicals have been shown to induce heritable translocations. These chemicals are either direct or indirect alkylating agents. The heritable-translocation test needs to be improved before it can be used in wide-scale practical testing. The most important question is whether or not historical controls can be used in tests for significance; the cost of concurrent controls is prohibitive. There is a need to standardize methods used in testing laboratories with respect to the size of error involved in classifying translocation heterozygotes and the power of the test. There is also a need to study in the effectiveness of non-alkylating clastogens in inducing heritable translocations in mice.