Gamma-ray-induced dominant mutations that cause skeletal abnormalities in mice. III

The criteria are discussed that permit the identification of carriers of dominant mutations in the absence of breeding tests. Initially this was to permit the recognition of as many mutations as possible among a few mice from a previously described mutation rate experiment, siring no progeny. However it was hoped to refine these criteria to make it practical evetually to omit breeding tests on a portion of the mutants or omit all breeding tests. The data suggest that the present criteria can identify about one-half of all dominant skeletal mutations on the basis of skeletal examination alone. These presumed-mutation criteria should give very few false positives. (C.F.)