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.
Digital polymerase chain reaction (dPCR) is a quantitative PCR method which gives a sensitive and reproducible way of clonally amplifying and measuring the amount of DNA or RNA present in a sample.
Droplet digital PCR (ddPCR) is a form of digital polymerase chain reaction (dPCR) that enables the precise quantification of target nucleic acids in a sample that has been clonally amplified.
Quantitative reverse transcription PCR (RT-qPCR) is a method to quantify the amplified product in real time by looking at the amount detected at a certain point of the run, as it is directly related to the initial amount of target in the sample.
Quantitative reverse transcription PCR is a method using RNA as a template. This RNA is reverse transcribed into complementary DNA (cDNA) by a reverse transcriptase. The quantity and purity of the RNA is important for RT-PCR success.