Mitochondrial genes support a common origin of rodent malaria parasites and Plasmodium falciparum's relatives infecting great apes
1 Méthodes et Algorithmes pour la Bioinformatique, LIRMM, UMR 5506, CNRS-Université de Montpellier 2, 161 rue Ada, 34392 Montpellier Cedex 5, France
2 Goldman Group, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK
3 Equipe Bonsai, Institut National de Recherche en Informatique et en Automatique, INRIA Lille Nord Europe, 40 avenue Halley, 59650 Villeneuve d'Ascq, France
Citation and License
BMC Evolutionary Biology 2011, 11:70 doi:10.1186/1471-2148-11-70Published: 15 March 2011
Plasmodium falciparum is responsible for the most acute form of human malaria. Most recent studies demonstrate that it belongs to a monophyletic lineage specialized in the infection of great ape hosts. Several other Plasmodium species cause human malaria. They all belong to another distinct lineage of parasites which infect a wider range of primate species. All known mammalian malaria parasites appear to be monophyletic. Their clade includes the two previous distinct lineages of parasites of primates and great apes, one lineage of rodent parasites, and presumably Hepatocystis species. Plasmodium falciparum and great ape parasites are commonly thought to be the sister-group of all other mammal-infecting malaria parasites. However, some studies supported contradictory origins and found parasites of great apes to be closer to those of rodents, or to those of other primates.
To distinguish between these mutually exclusive hypotheses on the origin of Plasmodium falciparum and its great ape infecting relatives, we performed a comprehensive phylogenetic analysis based on a data set of three mitochondrial genes from 33 to 84 malaria parasites. We showed that malarial mitochondrial genes have evolved slowly and are compositionally homogeneous. We estimated their phylogenetic relationships using Bayesian and maximum-likelihood methods. Inferred trees were checked for their robustness to the (i) site selection, (ii) assumptions of various probabilistic models, and (iii) taxon sampling. Our results robustly support a common ancestry of rodent parasites and Plasmodium falciparum's relatives infecting great apes.
Our results refute the most common view of the origin of great ape malaria parasites, and instead demonstrate the robustness of a less well-established phylogenetic hypothesis, under which Plasmodium falciparum and its relatives infecting great apes are closely related to rodent parasites. This study sheds light on the evolutionary history of Plasmodium falciparum, a major issue for human health.