Nucleic Acids in Chemistry and Biology

retroviruses have been recognised as particularly specialised forms of eukaryotic transposon. In effect they
are retrotransposons, which usually can leave the host cells and infect other cells. This ability is donated
by an extra gene (env) encoding a glycoprotein, which coats the virus, allowing entry and exit from the
host cell. The integrated DNA form (or provirus) of the retrovirus is almost identical to a retrotransposon.

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