• We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Logo of procbhomepageaboutsubmitalertseditorial board
Proc Biol Sci. Oct 22, 2000; 267(1457): 2037–2042.
PMCID: PMC1690779

The cause of parasitic infection in natural populations of Daphnia (Crustacea: Cladocera): the role of host genetics.


Disease patterns in nature may be determined by genetic variation for resistance or by factors, genetic or environmental, which influence the host-parasite encounter rate. Elucidating the cause of natural infection patterns has been a major pursuit of parasitologists, but it also matters for evolutionary biologists because host resistance genes must influence the expression of disease if parasite-mediated selection is to occur. We used a model system in order to disentangle the strict genetic component from other causes of infection in the wild. Using the crustacean Daphnia magna and its sterilizing bacterial parasite Pasteuria ramosa, we tested whether genetic variation for resistance, as determined under controlled conditions, accounted for the distribution of infections within natural populations. Specifically, we compared whether the clonally produced great-granddaughters of those individuals that were infected in field samples (but were subsequently 'cured' with antibiotics) were more susceptible than were the great-granddaughters of those individuals that were healthy in field samples. High doses of parasite spores led to increased infection in all four study populations, indicating the importance of encounter rate. Host genetics appeared to be irrelevant to natural infection patterns in one population. However, in three other populations hosts that were healthy in the field had greater genetic-based resistance than hosts that were infected in the field, unambiguously showing the effect of host genetic factors on the expression of disease in the wild.

Full Text

The Full Text of this article is available as a PDF (226K).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Bundy DA, Medley GF. Immuno-epidemiology of human geohelminthiasis: ecological and immunological determinants of worm burden. Parasitology. 1992;104 (Suppl):S105–S119. [PubMed]
  • Carroll MJ, Zangerl AR, Berenbaum MR. Heritability estimates for octyl acetate and octyl butyrate in the mature fruit of the wild parsnip. J Hered. 2000 Jan-Feb;91(1):68–71. [PubMed]
  • Chan L, Bundy DA, Kan SP. Genetic relatedness as a determinant of predisposition to Ascaris lumbricoides and Trichuris trichiura infection. Parasitology. 1994 Jan;108(Pt 1):77–80. [PubMed]
  • Clay K, Kover PX. The Red Queen Hypothesis and plant/pathogen interactions. Annu Rev Phytopathol. 1996;34:29–50. [PubMed]
  • Ebert D, Zschokke-Rohringer CD, Carius H-J. Within- and between-population variation for resistance of Daphnia magna to the bacterial endoparasite Pasteuria ramosa. Proc Biol Sci. 1998 Nov 7;265(1410):2127–2134. [PMC free article]
  • Gilbert SC, Plebanski M, Gupta S, Morris J, Cox M, Aidoo M, Kwiatkowski D, Greenwood BM, Whittle HC, Hill AV. Association of malaria parasite population structure, HLA, and immunological antagonism. Science. 1998 Feb 20;279(5354):1173–1177. [PubMed]
  • Scott ME. Heligmosomoides polygyrus (Nematoda): susceptible and resistant strains of mice are indistinguishable following natural infection. Parasitology. 1991 Dec;103(Pt 3):429–438. [PubMed]
  • Smith JA, Wilson K, Pilkington JG, Pemberton JM. Heritable variation in resistance to gastro-intestinal nematodes in an unmanaged mammal population. Proc Biol Sci. 1999 Jun 22;266(1425):1283–1290. [PMC free article] [PubMed]
  • Williams-Blangero S, Subedi J, Upadhayay RP, Manral DB, Rai DR, Jha B, Robinson ES, Blangero J. Genetic analysis of susceptibility to infection with Ascaris lumbricoides. Am J Trop Med Hyg. 1999 Jun;60(6):921–926. [PubMed]

Articles from Proceedings of the Royal Society B: Biological Sciences are provided here courtesy of The Royal Society


Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...


Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...