Cell-transforming ability of a temperature-sensitive mutant of polyoma virus

Conditional lethal mutants have been shown to be extremely useful in the study of the physiology of viral reproduction and maturation.(1, 2) Since such mutants are distributed over most of the genetic map,(1, 2) they could prove to be valuable in the study of tumor viruses. They may be used to "tag" almost all of the viral genes, a property of obvious physiological and genetical implication; they can also be useful for studying the mechanisms by which these viruses transform normal cells into cancer cells