title: Predominance of hybrid discrete typing units of Trypanosoma cruzi in domestic Triatoma infestans from the Bolivian Gran Chaco region.
abstract: In the Gran Chaco region the reinfestation by Triatoma infestans remains a major problem for control of Chagas disease. Trypanosoma cruzi the agent of the illness presents a broad genetic intraspecific variability which is poorly documented in the Bolivian Gran Chaco. This work presents the identification of the discrete typing units (DTUs) currently recognized for T. cruzi in T. infestans populations collected before and after residual insecticide spraying in four villages in this region. Before spraying, of 84 samples, the frequencies of the DTUs identified by using the multiplex PCR based on the non transcribed spacer of the mini-exon gene (MMPCR) were 0.21 for TcI, 0.70 for TcII/TcV/TcVI, and 0.17 for TcIII/TcIV and no significant difference was observed after spraying (76 samples). Moreover 13% of the total sample corresponds to T. infestans specimens with mixed infection of DTUs of which three were TcII/TcV/TcVI with TcIII/TcIV. The partial sequences of T. cruzi Gpi gene obtained from 14 PCR products agree the MMPCR DTU identification and allowed to precise the occurrence of TcIII, TcII and hybrid TcV/TcVI stocks which were not discriminated by the MMPCR. Given the high prevalence of hybrid stocks, the authors ask whether the recombination event at the origin of hybrids would have taken place in the Gran Chaco where the putative parents are also present.
authors.affiliation: MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle, Institut de Recherche pour le Développement (IRD), Representation in Bolivia, Av. Hernando Siles No. 5290, Esq Calle 7 Obrajes, CP 9214, La Paz, Bolivia.
authors.forename: Esdenka
authors.initials: E
authors.lastname: Perez
authors.forename: Marcelo
authors.initials: M
authors.lastname: Monje
authors.forename: Boris
authors.initials: B
authors.lastname: Chang
authors.forename: Rosio
authors.initials: R
authors.lastname: Buitrago
authors.forename: Rudy
authors.initials: R
authors.lastname: Parrado
authors.forename: Christian
authors.initials: C
authors.lastname: Barnabé
authors.forename: François
authors.initials: F
authors.lastname: Noireau
authors.forename: Simone Frédérique
authors.initials: SF
authors.lastname: Brenière
mesh_terms: D000818:Animals; D001838:Bolivia / Q000453:epidemiology; D014355:Chagas Disease / Q000453:epidemiology / Q000469:parasitology; D016054:DNA, Protozoan; D005260:Female; D005838:Genotype; D005956:Glucose-6-Phosphate Isomerase / Q000235:genetics; D006801:Humans; D007300:Insect Control; D008297:Male; D010802:Phylogeny; D015800:Protozoan Proteins / Q000235:genetics; D014224:Triatoma / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000235:genetics*
chemical_list: D016054:DNA, Protozoan; D015800:Protozoan Proteins; D005956:Glucose-6-Phosphate Isomerase