Tracing the Evolution of Virus

Most RNA viruses undergo mutations inside the host at an incessant rate that allows them to elude the immune response. This constant evolution in RNA viruses is due to the low fidelity in replication carried out by the virus encoded RNA dependent RNA polymerases. This mis-incorporation of bases leads to establishment of a quasispecies of virus in the host. This makes it a challenge to combat viral diseases. To trace the evolution of RNA viruses, researchers resort to sequencing of virus genomes. However, even next generation sequencing techniques that rely on massively parallel sequencing of genomes generate processing and systemic errors. Here, we propose a method to distinguish errors incorporated during reverse transcription (RT), a key step in processing and sequencing of all RNA molecules including RNA viral genomes. We hypothesize that by generating multiple cDNA copies from every individual RNA molecule, we can distinguish RT induced errors from real sequence variants in our sequences. This approach relies on generation of cDNA by reverse transcriptase in presence of UvrD helicase that unwinds the RNA-DNA hybrid enabling repeated cDNA generation.