Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-11-24T06:00:32.733Z Has data issue: false hasContentIssue false
  • English
  • Français

Gametocyte sex ratio of a malaria parasite: response to experimental manipulation of parasite clonal diversity

Published online by Cambridge University Press:  19 January 2004

S. M. OSGOOD  and
J. J. SCHALL
S. M. OSGOOD
Affiliation:
Department of Biology, University of Vermont, Burlington, Vermont 05405, USA
J. J. SCHALL
Affiliation:
Department of Biology, University of Vermont, Burlington, Vermont 05405, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

Sex ratio theory posits that the adaptive proportion of male to female gametocytes of a malaria parasite within the vertebrate host depends on the degree of inbreeding within the vector. Gametocyte sex ratio could be phenotypically flexible, being altered based on the infection's clonal diversity, and thus likely inbreeding. This idea was tested by manipulating the clonal diversity of infections of Plasmodium mexicanum in its lizard host, Sceloporus occidentalis. Naive lizards were inoculated with infected blood from a single donor or 3 pooled donors. Donors varied in their gametocyte sex ratios (17–46% male), and sex ratio theory allowed estimation of the clonal diversity within donor and recipient infections. Phenotypic plasticity would produce a correlation between donor and recipient infections for infections initiated from a single donor, and a less female-biased gametocyte sex ratio in recipients that received a mixed blood inoculum (with predicted higher clonal diversity) than recipients receiving blood from a single donor. Neither pattern was observed. Gametocyte sex ratio of most infections ranged from 35 to 42% male, expected if clonal diversity was high for all infections. Alternative explanations are suggested for the observed variation of gametocyte sex ratio among P. mexicanum infections.

Keywords

malariaPlasmodium mexicanumsex ratiogametocytePlasmodium spp
Type
Research Article
Information
Parasitology , Volume 128 , Issue 1 , January 2004 , pp. 23 - 29
Copyright
2004 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

ANDERSON, T. J. C., SU, X.-Z., BOCKARIE, M., LAGOG, M. & DAY, K. P. (1999). Twelve microsatellite markers for characterization of Plasmodium falciparum from finger-prick blood samples. Parasitology 119, 113–125.CrossRefGoogle Scholar
BRUCE-CHWATT, L. J. (1985). Essential Malariology, 2nd Edn. John Wiley, New York.
BURKOT, T. R., WILLIAMS, J. L. & SCHNEIDER, I. (1984). Infectivity to mosquitoes of Plasmodium falciparum clones grown in vitro from the same isolate. Transactions of the Royal Society of Tropical Medicine and Hygiene 78, 339–341.CrossRefGoogle Scholar
CHARNOV, E. L. (1982). The Theory of Sex Allocation. Princeton University Press, Princeton, New Jersey.
DAY, K. P., KOELLA, J. C., NEE, S., GUPTA, S. & READ, A. F. (1992). Population genetics and dynamics of Plasmodium falciparum: an ecological view. Parasitology 104, S35–S52.CrossRefGoogle Scholar
DYE, C. & GODFRAY, H. C. F. (1993). On sex ratio and inbreeding in malaria parasite populations. Journal of Theoretical Biology 161, 131–134.CrossRefGoogle Scholar
EISEN, R. J. (2000). Variation in life-history traits of Plasmodium mexicanum, a malaria parasite infecting western fence lizards: a longitudinal study. Canadian Journal of Zoology 78, 1230–1237.CrossRefGoogle Scholar
FERDIG, M. T. & SU, X.-Z. (2000). Microsatellite markers and genetic mapping in Plasmodium falciparum. Parasitology Today 16, 307–312.CrossRefGoogle Scholar
OSGOOD, S. M., EISEN, R. J. & SCHALL, J. J. (2002). Gametocyte sex ratio of a malaria parasite: Experimental test of heritability. Journal of Parasitology 88, 494–498.CrossRefGoogle Scholar
OSGOOD, S. M., EISEN, R. J., WARGO, A. R. & SCHALL, J. J. (2003). Manipulation of the vertebrate host's testosterone does not affect gametocyte sex ratio of a malaria parasite. Journal of Parasitology 89, 190–192.CrossRefGoogle Scholar
PAUL, R. E. L., COULSON, T. N., RAIBAUD, A. & BREY, P. TO. (2000). Sex determination in malaria parasites. Science 287, 128–131.CrossRefGoogle Scholar
PERKINS, S. L., OSGOOD, S. M. & SCHALL, J. J. (1998). Use of PCR for detection of subpatent infections of lizard malaria: implications for epizootiology. Molecular Ecology 7, 1587–1590.CrossRefGoogle Scholar
PICKERING, J., READ, A. F., GUERRERO, S. & WEST, S. A. (2000). Sex ratio and virulence in two species of lizard malaria parasites. Evolutionary Ecology Research 2, 171–184.Google Scholar
READ, A. F., NARARA, A., NEE, S., KEYMER, A. E. & DAY, K. P. (1992). Gametocyte sex ratios as indirect measures of outcrossing rates in malaria. Parasitology 104, 387–395.CrossRefGoogle Scholar
READ, A. F., ANWAR, M., SHUTLER, D. & NEE, S. (1995). Sex allocation and population structure in malaria and related protozoa. Proceedings of the Royal Society of London, B 260, 359–363.CrossRefGoogle Scholar
ROBERT, V., READ, A. F., ESSONG, J., TCHUINKAM, T., MULDER, B., VERHAVE, J. P. & CARNEVALE, P. (1996). Effect of gametocyte sex ratio on infectivity of Plasmodium falciparum to Anopheles gambiae. Transactions of the Royal Society of Tropical Medicine and Hygiene 90, 621–624.CrossRefGoogle Scholar
SCHALL, J. J. (1989). The sex ratio of Plasmodium gametocytes. Parasitology 8, 343–350.CrossRefGoogle Scholar
SCHALL, J. J. (1996). Malarial parasites of lizards: diversity and ecology. Advances in Parasitology 37, 255–333.CrossRefGoogle Scholar
SCHALL, J. J. (2000). Transmission success of the malaria parasite Plasmodium mexicanum into its vector: role of gametocyte density and sex ratio. Parasitology 121, 575–580.CrossRefGoogle Scholar
SCHALL, J. J. (2002). Parasite virulence. In The Behavioural Ecology of Parasites, (ed. Lewis, E. E., Campbell, J. F. & Sukhdeo, M. V. K.), pp. 283–313. CAB International, Oxon.CrossRef
SCHALL, J. J. & MARGHOOB, A. B. (1995). Prevalence of a malarial parasite over time and space: Plasmodium mexicanum in its vertebrate host, the western fence lizard Sceloporus occidentalis. Journal of Animal Ecology 64, 177–185.CrossRefGoogle Scholar
TAYLOR, L. H. (1997). Epidemiological and evolutionary consequences of mixed-genotype infections of malaria parasites. Ph.D. Dissertation, University of Edinburgh, UK.
WEST, S. A., SMITH, T. G. & READ, A. F. (2000). Sex allocation and population structure in apicomplexan (protozoa) parasites. Proceedings of the Royal Society of London, B 267, 257–263.CrossRefGoogle Scholar
WEST, S. A., SMITH, T. G., NEE, S. & READ, A. F. (2002). Fertility insurance and the sex ratios of malaria and related hemospororin blood parasites. Journal of Parasitology 88, 258–263.CrossRefGoogle Scholar