Radiation Induced Mutation Rates in Drosophila and Mice

This paper discusses the comparison of radiation-induced mutation rates in Drosophila and mice considering principally the data of Russell, Alexander and the author. It is argued that the comparison should be made on the basis of F1 results using only autosomal loci, for four reasons: (1) differences in viability and fertility of the presumptive F1 mutants in the two forms; (2) difference in time of separation of germ and somatic cell lines in the two forms; (3) the lack of knowledge on the comparative decrease in proportion of recovered mutations when testing sperm radiated at different developmental ages in the two forms; and (4) apparent differences in mutation rates of X-chromosomal and autosomal loci in Drosophila. Considering also the extreme non-randomness of the mutation rates of the few autosomal loci so far studied it is concluded that for the present the radiation-induced mutation rate per r per locus appears to be similar in flies and mice.