Current aspects on the radiation induced base damage in DNA.

In this short review, some current aspects of our knowledge about base damage in DNA induced by ionizing radiation will be summarized. It is not intended, to describe all the literature in this field; a very extensive review has been given in the book of Hüttermann et al. (1978) and also in later by Cadet and Berger (1985), Hutchinson (1985) and v. Sonntag and Schuchmann (1986). However, in this review, current ideas and unsolved problems concerning DNA base damage will be discussed, which may outline possible future research in this field. The understanding of DNA base damage requires the analysis of radicals formed in irradiated single DNA moieties as well as in whole DNA. Chemical studies about can be used for the molecular alterations of bases and biochemical methods for DNA-sequencing. In addition enzymes recognizing DNA damage and immunological methods with specific antibodies can be employed. However special emphasis should be given to the analysis of DNA base damage in irradiated cells and it will be shown, that a distinct gap in knowledge exists in this field in contrast to the radiation chemistry in aqueous solutions of DNA.