What are the common reverse transcription primers?

A primer is a short DNA oligonucleotide that binds to its complementary sequences on the DNA template. They serve as a starting point for synthesizing a new strand. Reverse transcription primers are necessary to initiate reverse transcription.

There are three basic types of reverse transcription primers - oligo(dT) primers, random primers, and gene-specific primers. The primer used in a reverse transcription process depends on the RNA template and the downstream applications.

Oligo(dT) primers are the preferred choice of primer for full-length cDNA cloning, construction of cDNA libraries from eukaryotic mRNAs and 3’ rapid amplification of cDNA ends.

Random primers are oligonucleotides with random base sequences. They are the preferred choice for reverse transcription of small RNAs, non-coding RNAs, prokaryotic mRNA, RNA with known secondary structures, RNAs without poly(A) tails, and degraded RNA. Random primers are not suitable for full-length reverse transcription of long RNA.

Sequence-specific primers greatly increase the sensitivity and specificity of the RT-PCR. It is the only type of primer that can be used for one-step applications.