Trypanosoma cruzi I genotypes in different geographic regions and transmission cycles based on a microsatellite motif of the intergenic spacer of spliced leader genes

CAROLINA I. CURA; ANA M. MEJÍA-JARAMILLO; TOMÁS DUFFY; JUAN M. BURGOS; MARCELA RODRIGUERO; MARTA V. CARDINAL; SONIA KJOS; RODRIGO GURGEL-GONÇALVES; DENIS BLANCHET; LUIS M. DE PABLOS; NICOLÁS TOMASINI; ALEX DA SILVA; GRACIELA RUSSOMANDO; CESAR A. CUBA CUBA; CHRISTINE AZNAR; TERESA ABATE; MARIANO J. LEVIN; ANTONIO OSUNA; RICARDO E. GÜRTLER; PATRICIO DIOSQUE; ALDO SOLARI; OMAR TRIANA-CHAVEZ; ALEJANDRO G. SCHIJMAN

Atlanta, Georgia, USA

Congreso; 59th Annual Meeting of American Society of Tropical Medicine and Hygiene; 2010

American Society of Tropical Medicine and Hygiene

The intergenic region of spliced-leader (SL-IR) genes from 105 Trypanosoma cruzi I infected biological samples, culture isolates and stocks from 11 endemic countries, from Argentina to USA, were characterised, allowing identification of 76 genotypes with 54 polymorphic sites from 123 aligned sequences. On the basis of the microsatellite motif proposed by Herrera et al. (2007) to define four haplotypes in Colombia, we could classify these genotypes into four distinct Tc I SL-IR groups, three corresponding to the former haplotypes Ia (11 genotypes), Ib (11 genotypes) and Id (35 genotypes); and one novel group, Ie (19 genotypes). Tc Ia was associated with domestic cycles in Southern and Northern South America and sylvatic cycles in Central and North America. Tc Ib was found in all transmission cycles from Colombia. Tc Id was identified in all transmission cycles from Argentina and Colombia, including Chagas cardiomyopathy patients, sylvatic Brazilian samples and human cases from French Guiana, Panama and Venezuela. Tc Ie gathered five samples from domestic Triatoma infestans from Northern Argentina, nine samples from wild Mepraia spinolai and Mepraia gajardoi and two chagasic patients from Chile and one from a Bolivian patient with chagasic reactivation. Mixed infections by Tc Ia + Tc Id, Tc Ia + Tc Ie and Tc Id + Tc Ie were detected in vector faeces and isolates from human and vector samples. In addition, Tc Ia and Tc Id were identified at different tissues from a heart transplanted Chagas cardiomyopathy patient with reactivation, denoting histotropism. T. cruzi I SL-IR genotypes from parasites infecting Triatoma gerstaeckeri and Didelphis virginiana from USA, T. infestans from Paraguay, Rhodnius nasutus and Rhodnius neglectus from Brazil and M. spinolai and M. gajardoi from Chile are described for the first time.