Some RNA viruses acquire the resistance against antiviral drugs by changing their genome

 RNA viruses often acquire the resistance against antiviral drugs. When we infect RNA viruses to culture cells with ribavirin, an antiviral drug, although almost all viruses cannot replicate, there appear some viruses that can grow even under the antiviral condition. These antiviral resistant viruses have some mutations within their genome. If we artificially generate such mutant viruses and analysis the effects of mutated viral gene, we will elucidate how RNA viruses acquire the antiviral state.