Population genetics of Trypanosoma brucei gambiense, the agent of sleeping sickness in Western Africa.
Human African trypanosomiasis, or sleeping sickness caused by Trypanosoma brucei gambiense, occurs in Western and Central Africa. T. brucei s.l. displays a huge diversity of adaptations and host specificities, and questions about its reproductive mode, dispersal abilities, and effective size remain under debate. We have investigated genetic variation at 8 microsatellite loci of T. b. gambiense strains isolated from human African trypanosomiasis patients in the Ivory Coast and Guinea, with the aim of knowing how genetic information was partitioned within and between individuals in both temporal and spatial scales. The results indicate that (i) migration of T. b. gambiense group 1 strains does not occur at the scale of West Africa, and that even at a finer scale (e.g., within Guinea) migration is restricted; (ii) effective population sizes of trypanosomes, as reflected by infected hosts, are probably higher than what the epidemiological surveys suggest; and (iii) T. b. gambiense group 1 is most likely a strictly clonally reproducing organism.
Koffi
Mathurin
M
Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Campus International de Baillarguet, 34398 Montpellier, Cedex 5, France. math_kof@yahoo.fr
De Meeûs
Thierry
T
Bucheton
Bruno
B
Solano
Philippe
P
Camara
Mamadou
M
Kaba
Dramane
D
Cuny
Gérard
G
Ayala
Francisco J
FJ
Jamonneau
Vincent
V
D000354:Africa, Western; D000818:Animals; D007560:Cote d'Ivoire; D014644:Genetic Variation; D005828:Genetics, Population; D016701:Guinea; D006801:Humans; D018895:Microsatellite Repeats; D019371:Topography, Medical; D014347:Trypanosoma brucei gambiense / Q000235:genetics* / Q000302:isolation & purification; D014353:Trypanosomiasis, African / Q000453:epidemiology / Q000469:parasitology* / Q000635:transmission