Lambda phage shuttle vectors for analysis of mutations in mammalian cells in culture and in transgenic mice

Foreign DNA sequences contained in lambda bacteriophage genomes integrated in mammalian DNA can be efficiently rescued into infectious phage particles by treatment of the mammalian DNA with lambda-packaging extracts prepared in E. coli. This system provides for rapid, non-selective recovery of stably integrated, chromosomal sequences into lambda phage for subsequent analysis in bacterial systems. Since rescue is prior to selection, mutations can be recovered from intact animals made transgenic for the phage-target gene sequences. Such approaches allow study of physiologically relevant aspects of mammalian mutagenesis at the molecular level.