Molecular methods for virus discovery

The potential use of novel cell substrates from diverse animal species raises concerns about the transmission of hitherto unknown viral agents. Viruses that do not cause a cytopathic effect in cell culture may escape detection by conventional methods and molecular methods may therefore prove useful for screening for hitherto unknown viruses. This review describes currently used molecular methods for virus discovery, including degenerate PCR assays, representational difference analysis and rolling circle amplification, and summarises the advantages and disadvantages of each technique.