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The retrotransposons move by a copy and paste mechanism and leave a copy at the original site during transcription. They are more common and move via RNA intermediate, which is a retrotransposon DNA transcript.

The RNA intermediate is converted into ds DNA by reverse transcriptase. The synthesized dsDNA is the mobile copy of retrotransposon, which gets pasted into a new location of DNA.

The transposon is cut out of its location and integrated into a new locationvia DNA intermediate, or it can move within a genome.It can move within a genome by a cut-and-paste or copy-and-paste mechanism.

The cut-paste or copy-paste mechanism both require a transposase enzyme which is usually encoded by the transposon.This enzyme cuts ds DNA to remove a transposon from one genomic site and incorporates it back into the DNA of the taget site, where a new cut is made.

The movement of retrotransposons involves the synthesis of ssRNA intermediate and whereas movement of transposon by cut-paste or copy-paste mechanism involves the synthesis of dsDNA intermediate.