Population structure of malaria parasites: the driving epidemiological forces.
The population structure of Plasmodial parasites, especially Plasmodium falciparum, has received much attention in the recent years. Like many other micropathogens, the debate has focused on the clonality/sexuality question. Considered a panmictic species for very long, P. falciparum actually exhibits strong departures from panmictic expectations in many of its populations, which corroborates the proposal that it is able to undergo uniparental propagation.(1) The currently accepted idea to account for this surprising result is kind of "mechanical" self-fertilization due to the lack of availability of gametes with different genetic make-ups in low transmission areas. However, it could be misleading to make this simple working hypothesis a dogma, for many other explanations are possible (unknown cycles, sibling species, mating types) that deserve to be explored as well. The consequences of this combination of uniparental(1) and sexual propagation on the circulation of genes of interest (drug resistance, antigenic variability, pathogenicity) are discussed, together with the need to use more sophisticated technologies, analysing much broader samples and considering better the host and vector factors in P. falciparum population dynamics.
Gauthier
C
C
Unit of Research 165 "Genetics and Evolution of Infectious Diseases", UMR CNRS/IRD 2724, IRD, BP 64501, 34394 Montpellier Cedex 5, France.
Tibayrenc
M
M
D000818:Animals; D000962:Antimalarials / Q000494:pharmacology / Q000627:therapeutic use; D018432:Drug Resistance, Multiple; D004812:Epidemiologic Methods; D005828:Genetics, Population; D006801:Humans; D016778:Malaria, Falciparum / Q000188:drug therapy / Q000453:epidemiology* / Q000469:parasitology* / Q000635:transmission; D010963:Plasmodium falciparum / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D011156:Population Density
D000962:Antimalarials