#retrovirus  any of a group of viruses that contain two single-strand linear RNA molecules per virion and reverse transcriptase (RNA to DNA)
  supertype:  animal_virus  an animal pathogen that is a virus
  subtype:  HTLV-1__human_T-cell_leukemia_virus-1  retrovirus causing T-cell leukemia
  subtype:  HIV__human_immunodeficiency_virus  the virus that causes acquired immune deficiency syndrome (AIDS); it replicates in and kills the helper T cells

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