Postlabelling methods for the detection of apurinic sites and radiation-induced DNA damage

This paper reviews the 32P-postlabelling techniques that have been employed in the detection and quantitation of apurinic sites and DNA damage induced by UV and ionizing radiation. The two major approaches utilize different enzymes for DNA digestion--in one case, micrococcal nuclease and calf spleen phosphodiesterase, and in the other DNase I, snake venom phosphodiesterase and calf intestinal phosphatase. As a result, each technique detects different classes of lesions with limited overlap and can, therefore, be considered complementary. The enzyme dependence and other technical aspects, in particular problems of background resulting from undamaged DNA, and some of the applications with cellular DNA and naked DNA, are discussed.