A technique for reconstruction and replication of randomly damaged double-stranded DNA, e.g. that found in mummified tissues or museum samples. In the first PCR cycle each primer is extended until a break in the template is encountered, but in the second cycle the newly synthesised strands find other templates that are intact in the region where the first templates were damaged. Each cycle extends the length of newly synthesised strands until complete strands are formed and PCR can begin its exponential synthesis.