Recombination: viruses exchange groups of genetic material (DNA or RNA).
Random mutation: an arbitrary change in the DNA or RNA sequence of a virus.
How does recombination take place?
It occurs when 2 viruses infect the same cell simultaneously. As they both use the same host cell to produce more virus particles, there will be lots of virus parts, which include newly synthesized genomes.
2 ways for recombination to occur:
Crossing over: similar regions of viral genomes pair up and exchange pieces of genetic material -> physically breaking and reconnecting
Reassortment: viruses with different segments exchange some of their segments.
Viral mutation: A change in the genetic code of a virus that can lead to the production of new viruses.
RNA viruses -> higher tendency to have high mutation rates
DNA viruses -> higher tendency to have low mutation rates
Why do RNA viruses have higher tendency to have high mutation rates?
DNA polymerase proofreads BUT RNA polymerase does NOT proofread.
