REDUCTION OF MISPRIMING IN AMPLIFICATION REACTIONS WITH RESTRICTED PCR

A simple method is described for reducing nonspecific background, whic h is caused by mispriming during PCR. Besides the standard pair of pri mers, 3'-dideoxy-terminated competitor oligonucleotides were added to the amplification. Sequences to those of the primers which had Identic al base. In this way enhanced specificity was achieved. The competitor oligonucleotides may act by masking possible sites of nonspecific pri mer-template interaction, thus excluding undesired chain extensions. T his technique is generally applicable when highly degenerate primers a re used and therefore expands the potential of ''restricted'' PCR.