In vivo mammalian mutagenesis: in transition to DNA molecules

Approaches are presented for the detection of mutations in the mitochondrial and nuclear DNA of somatic and germinal cells in vivo in mammals. The difficulties in evaluating mitochondrial mutagenesis are stressed, and simulation experiments using oogonial transfer techniques with mitochondria from two closely subspecies, Mus musculus and Mus molossinus, are suggested. Arguments are presented for using transgenic animals in the study of mutagenesis in the nuclear genome instead of native DNA. Presently, the selection of vectors is limited to lambda and phi X174. The preferred mutation detection system should be independent of expression of the mutant phenotype in the mammalian cells.