Recombination and gene conversion

Recombination is an important aspect of DNA metabolism. It leads to rearrangements of DNA sequences within genomes. Such genome rearrangements seem to be ubiquitous, since they play a role in evolution, human health and biotechnology. In medicine one important aspect of recombination is its role as one possible step in the multistep process of carcinogenesis. Since recombination may occur as a cellular response to DNA damage, the protection of cells from recombination-inducing agents, so-called recombinagen, should eliminate possible deleterious effects resulting from damage-induced DNA recombination. During the last few years, the awareness of the importance of recombination phenomena has substantially increased and the development of assay systems detecting recombinagens has progressed. The need for considering recombinagenic effects as a safety aspect of chemicals has gained ground in the field of genetic toxicology. This paper summarizes present knowledge concerning the occurence, inducibility, detection and toxicological interpretation of DNA recombination.