Viral DNA or RNA
Country: United States
Date: October 2007
would it make a difference if the genetic material in
chicken pox was RNA and not DNA?
If a virus has RNA in it instead of DNA, it needs an enzyme known as reverse
transcriptase to reverse-transcribe its RNA into DNA. Retroviruses have RNA
and reverse transcriptase, where as a virus like the Varicella-Koster virus
(a scientific name for the chicken pox virus) does not.
Hope this helps,
Variola, the virus that causes chicken pox is a DNA virus. This is important
because the enzyme that makes more DNA, DNA polymerase, has a "spell check"
function. If it makes mistakes while copying DNA, it can fix them. RNA
viruses, such as AIDS and the flu, don't have this. So they mutate much
faster. This is why you can take a vaccine for chicken pox and have it
last a lifetime, but need a flu shot every year. We still haven't been
able to create a vaccine for AIDs because it mutates so quickly.
Some viruses have evolved using RNA as their genetic material and some
have evolved using DNA. Once a genetic system has evolved over millions
of years, it is "stuck" with the system it evolved with, i.e., there is
no going back!
Ron Baker, Ph.D.
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Update: June 2012