Effects of ENU dosage on mouse strains

The germline supermutagen, N-ethyl-N-nitrosourea (ENU), has a variety of ef fects on mice. ENU is a toxin and carcinogen as well as a mutagen, and stra ins differ in their susceptibility to its effects. Therefore, it is necessa ry to determine an appropriate mutagenic, non-toxic dose of ENU for strains that are to be used in experiments. In order to provide some guidance, we have compiled data from a number of laboratories that have exposed male mic e from inbred and non-inbred strains or their F-1 hybrids to ENU. The resul ts show that most F-1 hybrid animals tolerate ENU well, but that inbred str ains of mice vary in their longevity and in their ability to recover fertil ity after treatment with ENU.