Radiation-induced damage in DNA

Abstract

Publisher Summary The radiation chemistry of deoxyribose nucleic acid (DNA) has generally been studied to gain a detailed understanding of the chemical modifications induced in DNA by ionizing radiation. This chapter focuses on the chemistry of DNA damage, how the DNA structure may alter the chemistry and distribution of products, and how this damage may influence the biological effects of ionizing radiation. To date, the majority of the information on radiation-induced DNA damage comes from the use of low linear energy transfer (LET) radiations, such as γ- radiation, hard X-rays, and high energy electrons. The latter type of radiation is generated by accelerators and is generally used in the technique of pulse radiolysis, which has provided most of the quantitative information on the reactivity and types of DNA radicals. Pulse radiolysis has provided the majority of information on the interactions of water radicals with DNA. Other techniques and in particular electron spin resonance (ESR) have provided the majority of information on the types of damage produced by direct energy deposition in DNA. Ionizing radiation randomly induces a variety of damages to cellular DNA. The most frequent types of DNA damage produced are single (ssb) and double (dsb) strand breaks, base and sugar modifications, and DNA-protein crosslinks.