Fitness of RNA virus decreased by Muller's ratchet (original) (raw)

Nature volume 348, pages 454–455 (1990)Cite this article

Abstract

WHY sex exists remains an unsolved problem in biology1–3. If mutations are on the average deleterious, a high mutation rate can account for the evolution of sex4. One form of this mutational hypothesis is Muller's ratchet5,6. If the mutation rate is high, mutation-free individuals become rare and they can be lost by genetic drift in small populations. In asexual populations, as Muller5 noted, the loss is irreversible and the load of deleterious mutations increases in a ratchet-like manner with the successive loss of the least-mutated individuals. Sex can be advantageous because it increases the fitness of sexual populations by re-creating mutation-free individuals from mutated individuals and stops (or slows) Muller's ratchet. Although Muller's ratchet is an appealing hypothesis, it has been investigated and documented experimentally in only one group of organisms—ciliated protozoa2. I initiated a study to examine the role of Muller's ratchet on the evolution of sex in RNA viruses and report here a significant decrease in fitness due to Muller's ratchet in 20 lineages of the RNA bacteriophage Φ6. These results show that deleterious mutations are generated at a sufficiently high rate to advance Muller's ratchet in an RNA virus and that beneficial, backward and compensatory mutations cannot stop the ratchet in the observed range of fitness decrease.

This is a preview of subscription content, access via your institution

Access options

Subscribe to this journal

Receive 51 print issues and online access

$199.00 per year

only $3.90 per issue

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Additional access options:

Similar content being viewed by others

References

  1. Maynard Smith, J. The Evolution of Sex (Cambridge University Press, Cambridge, 1976).
    Google Scholar
  2. Bell, G. Sex and Death in Protozoa. The History of an Obsession (Cambridge University Press, Cambridge, 1988).
    Google Scholar
  3. Michod, R. & Levin, B. R. The Evolution of Sex. An Examination of Current Ideas (Sinauer, Sunderland, 1988).
    Google Scholar
  4. Kondrashov, A. S. Nature 336, 435–440 (1988).
    Article ADS CAS PubMed Google Scholar
  5. Muller, H. J. Mut. Res. 1, 1–9 (1964).
    Article Google Scholar
  6. Felsenstein, J. Genetics 78, 737–756 (1974).
    CAS PubMed PubMed Central Google Scholar
  7. Holland, J. et al. Science 215, 1577–1585.
  8. Chao, L. J. theor. Biol. 133, 99–112 (1988).
    Article CAS PubMed Google Scholar
  9. Semancik, J. S., Vidaver, A. K. & Van Etten, J. L. J. molec. Biol. 78, 617–625 (1973).
    Article CAS PubMed Google Scholar
  10. Horiuchi, K. in RNA Bacteriophages (ed. Zinder, N. D.) 29–50 (Cold Spring Harbor Laboratory, New York, 1975).
    Google Scholar
  11. Mindich, L., Sinclair, J. F., Levine, D. & Cohen, J. Virology 75, 218–223 (1976).
    Article CAS PubMed Google Scholar
  12. Mindich, L., Cohen, J. & Weisburd, M. J. Bact. 126, 177–182 (1976).
    CAS PubMed PubMed Central Google Scholar
  13. Sinclair, J. F., Cohen, J. & Mindich, L. Virology 75, 198–208 (1976).
    Article CAS PubMed Google Scholar
  14. Maniatis, T., Fritsch, E. F. & Sambrook, J. Molecular Cloning. A Laboratory Manual (Cold Spring Harbor Laboratory, New York, 1982).
    Google Scholar
  15. Sokal, R. R. & Rolf, F. J. Biometry (Freeman, San Francisco, 1981).
    Google Scholar
  16. Falconer, D. S. Introduction to Quantitative Genetics, 2nd ed. (Longman, Harlow, 1981).
    Google Scholar
  17. Wagner, G. P. & Gabriel, W. Evolution 44, 715–731 (1990).
    Article PubMed Google Scholar
  18. Lenski, R. Science 248, 901 (1990).
    Article Google Scholar
  19. Becker, W. A. Manual of Quantitative Genetics, 3rd ed. (Washington State University Press, Pullman, 1975).
    Google Scholar

Download references

Author information

Authors and Affiliations

  1. Department of Zoology, University of Maryland, College Park, Maryland, 20742, USA
    Lin Chao

Authors

  1. Lin Chao
    You can also search for this author inPubMed Google Scholar

Rights and permissions

About this article

Cite this article

Chao, L. Fitness of RNA virus decreased by Muller's ratchet.Nature 348, 454–455 (1990). https://doi.org/10.1038/348454a0

Download citation