Biological applications of ionizing radiation

Ionizing radiation is cytotoxic, mutagenic and carcinogenic. For these reasons it provides an important line of research for the radiation biologist. It exerts its cytotoxicity primarily by its damaging effects on DNA but also by causing damage to a variety of other structures in the cell such as organelles and membranes. The mutagenic effects of ionizing radiation are due to a variety of lesions in DNA that include single and double strand breaks, base modifications and misrepair of damage. The well established correlation between carcinogenicity and mutagenicity can readily account for the ability of radiation to cause cancer. Over the past several years we have studied the effects of radiation on human cells. We have employed both γ-rays (60Co source) and neutrons (produced in the Van de Graaff at Lucas Heights) in this project. Our overall aim was to understand in greater detail the relationship between radiation damage, cell death and malignancy. This general approach has allowed for the elucidation of DNA repair mechanisms and identification of enzymes involved in these processes