[Reverse genetics in reovirus study: advances, difficulties and perspectives]

In "classical" genetics, examination of a phenotype leads to the study of the gene(s) involved in its obtention. Reverse genetics is a powerful experimental approach in which, on the contrary, the genetic material is modified and used to reconstruct a complete organism in order to study the result of these modifications. This approach is especially well adapted to the study of viruses, considering their relative simplicity and small size of their genomes; the main obstacle remains to recover infectious viruses from cloned viral genomes. Over the years, this exploit has been achieved with representatives of almost all families of mammalian viruses. Until recently, the Reoviridae, viruses with segmented double-stranded RNA genome, were an exception. In this review, the progress accomplished toward the development of such an approach for the Orthoreovirus will thus be discussed. Reverse genetics could have a major impact for the optimization of novel virus strains for their use in therapy as oncolytic viruses and for the development of vaccines in the case of Rotavirus and Orbivirus. However, current works stress the limitations of the approach, the need for careful analysis of the results obtained, as well as the necessity to develop more efficient and polyvalent systems.