transfer of viral genes to the cell is mediated by an enzyme called reverse transcriptase (or, more precisely, RNA-dependent DNA polymerase), which replicates the viral genome (in this case made of RNA) into DNA, which is later incorporated in the host genome. Oncoviruses are the cause of some forms of human cancers. Dulbecco's study gave a basis for a precise understanding of the molecular mechanisms by which they propagate, thus allowing humans to better fight them. Furthermore, the mechanisms of carcinogenesis mediated by oncoviruses closely resemble the process by which normal cells degenerate into cancer cells. Dulbecco's discoveries allowed humans to better understand and fight cancer. In addition, it is well known that in the 1980s and 1990s, an understanding of reverse transcriptase and of the origins, nature, and properties of human immunodeficiency virus (HIV, of which there are two well-understood serotypes, HIV-1, and the less-common and less virulent HIV-2), the virus which, if unchecked, ultimately causes acquired immunodeficiency syndrome (AIDS), led to the development of the first group of drugs that could be considered successful against the virus, the reverse-transcriptase inhibitors, of which zidovudine is a well-known example. These drugs are still used today as one part of the highly-active antiretroviral therapy drug cocktail that is in contemporary use. Other awards In 1965 he received the Marjory Stephenson Prize from the Society for General Microbiology. That same year, he was elected to the American Academy of Arts and Sciences. In 1973 he was awarded the Louisa Gross Horwitz Prize from Columbia University together with Theodore Puck and Harry Eagle. Dulbecco was the recipient of the Selman A. Waksman Award in Microbiology from the National Academy of Sciences in 1974. He was elected a Foreign Member of the Royal Society (ForMemRS) in 1974. In 1993, he was elected to the American Philosophical Society. References External links 1914 births 2012 deaths American Nobel laureates California Institute of Technology faculty Foreign Members of the Royal Society Italian emigrants to the United States Italian military personnel of World War II Italian Nobel laureates Italian resistance movement members Members of the United States National Academy of Sciences Nobel laureates in Physiology or Medicine People from Catanzaro Physicians from Turin University of Turin alumni Italian virologists Recipients of the Albert Lasker Award for Basic Medical Research Salk Institute for Biological Studies people Members of the American Philosophical Society