The reproducibility and potential applications of anonymous amplification protocols can be improved by using pairs of primers, each of 18 to 24 bases, to replace the single 8 to 10 base primers normally used in randomly amplified polymorphic DNA (RAPD) or DNA amplification fingerprinting (DAF) methods. Amplification using large primer pairs (LP-RAPD) generates 5 to 30 bands that can be resolved on standard agarose gels. Complex fingerprints can be readily generated from viruses, bacteria, fungi, plants, invertebrates and vertebrates. We also present evidence that a number of polymerase chain reaction (PCR) methods, including those based on the use of enterobacterial repetitive intergenic consensus (ERIC-PCR) or microsatellite primed (MP-PCR) sequence, may in essence operate by the same mechanism as LP-RAPD. Using standard LP-RAPD protocols, reproducible fingerprints can be generated from a single specimen using different thermocyclers, regardless of the mechanism used for thermocycling (air-cooled, Peltier effect, or robotic arm). LP-RAPD is sensitive to intraspecific and interspecific genetic variation, demonstrated here by analysis of mites and apple cultivars. Approximately 50% of LP-RAPD products are expected to have different primers at either end. Polymorphic bands with this arrangement can be recovered from the gel and directly sequenced using the LP-RAPD primers themselves. The efficiency of sequencing is improved by the length of the LP-RAPD primers. This method has the potential to allow the production of allele-specific species markers in less than two days.
- microsatellite primed polymerase chain reaction
- polymerase chain reaction DNA fingerprinting
- randomly amplified polymorphic DNA
- repetitive element polymerase chain reaction