[Bacterial resistance factors as vectors for gene manipulation and gene therapy (author's transl)]

Bacterial resistance factors are extrachromosomal elements, consisting of circular closed, double stranded DNA. They may contain genes which make the host bacterium resistant to certain antibiotics. Such resistance factors have become important vectors for selective replication of specific segments of all kinds of DNA. Suitable DNA segments are obtained by treating DNA with restriction endonucleases of defined cutting properties. They can then be linked to the respective vector. It was thus possible to anneal DNA segments originating from the same, but also from different bacterial resistance factors. They gave biologically functional units. The annealed products can be propagated in bacteria. The relevant experiments are described. Their potential dangers for man, and efforts to agree on suitable safety regulations are discussed.