Retrovirus

An RNA virus (a virus composed not of DNA but of RNA). Retroviruses have an enzyme called reverse transcriptase that gives them the unique property of transcribing RNA (their RNA) into DNA. The retroviral DNA can then integrate into the chromosomal DNA of the host cell to be expressed there. The human immunodeficiency virus (HIV), the cause of AIDS, is a retrovirus.

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Any virus of the family Retroviridae.Retroviruses are potent disease agents, but they have also served as invaluable research tools in molecular biology. In 1979, the molecular biologist Richard Mulligan used a genetically altered r. to trigger the production of hemoglobin in vitro by monkey kidney cells. His technique for using retroviruses to import alien genes into cells has been widely adopted. Medical researchers have also explored retroviral transport as a means of gene therapy. However, evidence suggesting that retroviruses may play a role in carcinogenesis raises questions as to the safety of their use in gene therapy. See oncogene.

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ret·ro·vi·rus 're-trō-.vī-rəs n any of the family Retroviridae of single-stranded RNA viruses called also RNA tumor virus

ret·ro·vi·ral -rəl adj

ret·ro·vi·ral·ly -ē adv

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n.

an RNA-containing virus that can convert its genetic material into DNA by means of the enzyme reverse transcriptase, which enables it to become integrated into the DNA of its host's cells. Retroviruses have been implicated in the development of some cancers and are associated with conditions characterized by an impaired immune system (HIV is a retrovirus). They are also used as vector in gene therapy.

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ret·ro·vi·rus (retґro-vi″rəs) any virus of the family Retroviridae. retroviral adj