AIDS is caused by the<unk> (HIV). HIV is a retrovirus classified into the family of Retroviridae and the sub family orthoretroviridae..  Two main subspecies of HIV exist: HIV-1, and HIV-2. HIV-1 is composed of two copies of single-stranded RNA enclosed by a conical capsid comprising the viral protein p24. The genome consists of several major genes that code for structural and functional proteins. These include the gag, pol, env, tat, and nef genes. The genome and proteins of HIV have been the subject of extensive research since the discovery of the<unk>  in 1983. It is a well known fact that no two HIV genomes are the same, not even from the same person, causing some to speculate that HIV is a "quasispecies" of a<unk> .  A major requirement for all retroviruses is reverse transcriptase that transcribes the viral RNA into double-stranded DNA and integrase that integrates this newly formed DNA into the host genome.
Human Immunodeficiency Virus 
Opportunistic infection
Environmental radioactivity
Infectious disease
Dietary supplement
Sexually transmitted disease
Foodborne Illness
Blood-borne disease