Polymerase chain reaction (PCR)
Polymerase chain reaction (PCR) is a laboratory analysis used to detect small amounts of DNA in a sample by amplifying the DNA to measurable quantities. PCR allows DNA sequences to be exponentially amplified, generating thousands to millions of copies of the particular DNA segment being amplified. The amplification starts by heating the sample to denature the double helix DNA strand into two single-stranded DNA molecules. An enzyme called "Taq Polymerase" is used to synthesize and build two new strands of DNA, using the original strands as templates.