Mutagenicity, toxicity and repair of DNA base damage induced by oxidation.

Oxidative DNA damage is a major cause of cell death and mutagenesis in all aerobic organisms, and several new oxidative base lesions have been identified in recent years. Improved chemistry for the synthesis of oligonucleotides with modified base residues at defined positions has allowed detailed studies of repair, replication, transcription and mutagenesis at specific lesions in vitro and in vivo. The aim of this review is to present the structure of all the various known oxidised DNA base lesions known to date and to summarise the present knowledge about the mutagenic and toxic effects of oxidised base modifications and their repair.