reverse transcriptase

In the fields of molecular biology and biochemistry, a reverse transcriptase, also known as RNA-dependent DNA polymerase, is a DNA polymerase enzyme that transcribes single-stranded RNA into single-stranded DNA.

It also is a DNA-dependent DNA polymerase which synthesizes a second strand of DNA complementary to the reverse-transcribed single-stranded cDNA after degrading the original mRNA. Normal transcription involves the synthesis of RNA from DNA; hence, reverse transcription is the reverse of this.

Human telomerase is also a reverse transcriptase.