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any of a group of viruses that contain two single-strand linear RNA molecules per virion and reverse transcriptase (RNA to DNA)

any of a group of viruses that contain two single-strand linear RNA molecules per virion and reverse transcriptase (RNA to DNA)

Family of RNA viruses that infects birds and mammals and encodes the enzyme reverse transcriptase. The family contains seven genera: DELTARETROVIRUS; LENTIVIRUS; RETROVIRUSES TYPE B, MAMMALIAN; ALPHARETROVIRUS; GAMMARETROVIRUS; RETROVIRUSES TYPE D; and SPUMAVIRUS. A key feature of retrovirus biology is the synthesis of a DNA copy of the genome which is integrated into cellular DNA. After integration it is sometimes not expressed but maintained in a latent state (PROVIRUSES).