Add 4 μl of 160 mM KMnO4 to radiolabeled DNA (40 ng, 5,000-10,000 cpm) in 40 μl total volume. 2. Incubate for 2 min at 30 °C, stop reaction with 4.8 μl β-mercaptoethanol, add 5.3 μl 500 mM EDTA. 3. Extract with phenol/chloroform, precipitate with ethanol, centrifuge, dissolve in 70 μl 10% piperidine, incubate at 90 °C for 30 min. 4. Lyophilize, dissolve in 30 μl water, lyophilize again, repeat. 5. Dissolve in 50 μl water, add 4 μl 300 mM NaOAc, 1 μl glycogen, precipitate with ethanol. 6. Wash pellets with 70% ethanol, dry, dissolve in 5 μl electrophoresis loading buffer. 7. Separate on 10-15% denaturing polyacrylamide gel, visualize bands by autoradiography. 8. For non-labeled DNA, follow similar steps, add 5'-32P-labeled primer, perform primer extension, separate on denaturing gel, visualize by autoradiography.