IDEA   23902
INSTITUTO DE DIVERSIDAD Y ECOLOGIA ANIMAL
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Population genetics and Phylogeography of the Triatoma dimidiata complex.
Autor/es:
PECH-MAY A, MAZARIEGOS-HIDALGO CJ, IZETA-ALBERDI A, TUN-KU E, DE LA CRUZ-FK, LÓPEZ-CANCINO SA, IBARRA-CERDEÑA C, GONZÁLEZ ITTIG RE, RAMSEY JM
Lugar:
Cuernavaca
Reunión:
Congreso; II Congreso Internacional de Vectores (Hemíptera: Reduviidae: Triatominae) y del Trypanosoma cruzi y en el II Simposio Internacional sobre la Enfermedad de Chagas; 2016
Institución organizadora:
Universidad Autonoma del Estado de Morelos
Resumen:
Triatoma dimidata is one of the broadest distributed triatomine species´ complexes transmitting Trypanosoma cruzi, and is the only one to naturally extend from Mexico through Central America, to Ecuador, Peru, Colombia, Venezuela, and French Guyana. Several studies have analyzed population structure within the complex, although none have analyzed a representative sample of the three major haplogroups, where they are all sympatric. Triatoma dimidiata population structure was analyzed across human communities on a regional scale in Berriozabal county, Chiapas, and within a discrete fragmented landscape therein, and phylogeography of the complex was analysed on a Mexican (Chiapas, Campeche, Yucatán, Oaxaca, San Luis Potosí, Veracruz) and continental scale (Genbank sequences from other countries). Since primer-binding site polymorphisms are not equivalent across the 3 principal haplogroups, a second fragment from the ND4 gene was designed, and concatenated sequences analysed. All three haplogroups were present in the northern Berriozabal sub-region, Hg2 was the most prevalent. Genetic diversity was moderate regionally, with highest in the northwest conserved sub-regions. There was high haplotype diversity across the Mexican Neotropics (31-54), although nucleotide diversity was low. Hg1 and Hg2 neutrality analyses indicate that both are expanding. There was high genetic differentiation with greatest distance between Hg1 and Hg3 for the ND4B and the concatenated sequences. The inferred phylogeny (IP) of the concatenated sequences for Mexico confirmed three haplogroups, with a MRCA at 0.74 MYA. Divergence between Hg2 and Hg3 was estimated at 0.45 MYA, and first level divergence of Hg1 not until 0.124 MYA. The continental IP (all LA for ND4A) estimated the MRCA at 0.77 MYA, and divergence between Hg2 and Hg3 estimated at 0.51 MYA. The Bayesian skyline plot indicated an effective dimidiata complex population increase approximately 0.025 MYA. The concatenated analysis confirms the sensitivity of these combined gene fragments to analyze phylogenetic associations and identify major and secondary clades even when they are sympatric. Biogeographic barriers are associated with divergence among haplogroups, Hg2 the only one north and west of the Tehuantepec Isthmus, while Hg1 is not found south of the Sierra Madre of Chiapas, and Hg3 has not dispersed north of the Grijalva and Usumacinta watersheds.