ABSTRACT
Polymerase chain reaction (PCR) is an in vitro technique for amplifying a target DNA sequence in a short time. This is because both strands of DNA are copied simultaneously during PCR; therefore, there is an exponential increase in the number of copies of the target DNA fragment or gene with each cycle (1,2). Three fundamental aspects make PCR such a powerful tool in determining the qualitative expression of target genes:
1. PCR is less expensive, less time-consuming, and simpler than previous DNA (and RNA) duplication techniques, making it possible for anyone, even one with no training in molecular biology, to do genetic and molecular biological research.
