Figure 1.

General principle of MAPH. Test DNA is denatured and hybridised with a set of amplifiable probes, each recognising a unique region in the genome. After stringent washing to allow retention only of specifically bound probes, the bound probe fragments are amplified using a common primer pair and quantified, for example after polyacrylamide gel electrophoresis. Since an excess of probe is used, the amount of each probe recovered will be proportional to the copy number of the corresponding sequence in the test DNA.