Quantitation of DNA fragmentation using fiberglass filters

Many types of physiological and toxicological cell killing are mediated by extensive DNA fragmentation. To date, most assays used to detect DNA fragmentation have relied on cumbersome techniques to separate intact chromatin from cleaved DNA. Here we describe a filtration assay for quantitation of DNA fragmentation. Fiberglass filtermats were used to separate intact chromatin from DNA fragments. Analysis of the separation showed that intact chromatin consistently remained on filters, while DNA fragments of all (random) sizes were consistently found in the filtrates. The assay was adaptable to different DNA detection procedures and generated results comparable to those obtained using established methods in standard model systems.