Development & Classification

Development of retroviruses

Studies of retroviruses led to the first demonstrated synthesis of DNA from RNA templates, a fundamental mode for transferring genetic material that occurs in both eukaryotesand prokaryotes. It has been speculated that the RNA to DNA transcription processes used by retroviruses may have first caused DNA to be used as genetic material. In this model, the RNAworld hypothesis, cellular organisms adopted the more chemically stable DNA when retroviruses evolved to create DNA from the RNA templates.

Classification

Exogenous
The following genera are included here:

Alpharetrovirus - Avian leukosis virus
Betaretrovirus - Mouse mammary tumour virus
Gammaretrovirus - Murine leukemia virus, Feline leukemia virus
Deltaretrovirus - Bovine leukemia virus Human T-lymphotrophic virus
Epsilonretrovirus - Walleye dermal sarcoma virus
Lentivirus - Human Immunodeficiency virus 1, Simian and Felian Immunodeficiency viruses Spumavirus - Chimpanzee foamy virus