Primer

A short DNA or RNA fragment annealed to single-stranded DNA, from which DNA polymerase extends a new DNA strand to produce a duplex molecule.

A short oligonucleotide anneal ed to a template of single-stranded DNA, providing a doubled stranded structure from which DNA polymerase will synthesize a new DNA strand to produce a duplex molecule.

A short oligonucleotide sequence used in a polymerase chain reaction. See also

Short preexisting polynucleotide chain to which new deoxyribonucleotides can be added by DNA polymerase.