Life Science

The polymerase chain reaction (PCR) is an efficient and rapid in vitro method for enzymatic amplification of specific DNA or RNA sequences. A simple PCR reaction consists of target DNA, a thermostable DNA polymerase, dNTPs and synthetic oligonucleotide primers that flank the target DNA sequence. A repetitive series of cycles involving template denaturation, primer annealing, followed by extension of the annealed primers, yields tremendous amounts of DNA. Because the strands synthesized in one cycle serve as a template in the next, a million-fold increase in the DNA amount is achieved in just 20 cycles.