Antonie van Leeuwenhoek

, Volume 81, Issue 1, pp 135–142

Restrictions to RNA virus adaptation: An experimental approach


  • Santiago F. Elena
    • Institut Cavanilles de Biodiversitat i Biologia Evolutiva and Departament de GenèticaUniversitat de València, Edifici d'Instituts d'Investigació, Campus de Burjassot-Paterna

DOI: 10.1023/A:1020589929125

Cite this article as:
Elena, S.F. Antonie Van Leeuwenhoek (2002) 81: 135. doi:10.1023/A:1020589929125


Some basic properties of RNA viruses are their high mutation rate, their enormous population sizes and their short generation time. These properties allow RNA virus populations to quickly explore fitness landscapes. A great adaptability has been amply demonstrated in experimental, as well as in natural, populations of RNA viruses. However, at least from a theoretical point of view, a limit to the extent of viral adaptation may exist as a consequence of adaptive trade-offs arising during evolution in changing environmental conditions. Here, I review previously published results searching for such fitness trade-offs. The following scenario has been explored: the cost of host-range expansion, the cost of resistance to antiviral drugs, and the adaptation to different population densities. Despite the environmental conditions tested, results show a common pattern: whenever a virus adapt to a simple environmental situation it pays a cost in terms of adaptation to alternative situations. However, in those cases where the virus has been simultaneously adapted to different environmental conditions, this cost disappears or, at least, is greatly reduced. Finally, and as another factor imposing a limit to their speed of adaptation, I review results showing that clonal interference also plays an important role during viral evolution.

evolutionary constraintsexperimental evolutionfitnessniche expansiontrade-offs

Copyright information

© Kluwer Academic Publishers 2002