A primer is a short, single-stranded DNA sequence used in the polymerase chain reaction (PCR) technique. In the PCR method, a pair of primers is used to hybridize with the sample DNA and define the region of the DNA that will be amplified. Primers are also referred to as oligonucleotides.


Primer refers to a small set of nucleotides of DNA, typically 18 to 24 base pairs in length. And a primer can be used for a multitude of other experimental processes. You can use primer in PCR to target a locus to allow for amplification for further analysis. You'd use a primer for sequencing a sequencing reaction where you want to target a very specific region and then do analysis in the extension of that DNA molecule.

- Stacie Loftus, Ph.D.