DNA Viruses?

Which DNA viruses have been linked to cancer? Why are DNA viruses more likely to cause cancer than RNA viruses? Why is there a danger in using live attenuated DNA viruses for vaccines?

DNA Viruses?norten

First of all, a DNA virus is a virus in which the nucleic acid is double or single stranded DNA (rather than RNA). Major groups of double stranded DNA viruses are papovaviruses, adenoviruses, herpes viruses, large bacteriophages and poxviruses: of single stranded, parvoviruses and coliphages _X174 and M13.

Examples of DNA viruses are the JC virus, which has been found in malignant colon tumors and may be linked to colon cancer. There is also, the Human Papilloma Virus (HPV), a DNA virus, which causes transformation in cells through interfering with tumor suppressor proteins. Interfering with the action of the particular suppressor protein allows a cell infected with the virus to move into a different stage of the cell cycle allowing the virus genome to be replicated forcing the cell into the S phase of the cell cycle could cause the cell to become transformed. Another example is human herpes virus-8, which is associated with Kaposi鈥檚 sarcoma, a type of skin cancer. Also, epstein barr virus (EBV) is associated with four types of cancers.

Retroviruses are different from DNA tumor viruses in that their genome is RNA but they are similar to many DNA tumor viruses in that the genome is integrated into host genome.