Trypanosoma cruzi: presence of the two major phylogenetic lineages and of several lesser discrete typing units (DTUs) in Chile and Paraguay

• Published in: Acta tropica Vol. 78; no. 2; pp. 127 - 137
• Main Authors: Barnabé, Christian, Neubauer, Katja, Solari, Aldo, Tibayrenc, Michel
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 23.02.2001; Elsevier
• Subjects: Animals; Biological and medical sciences; Chagas Disease - epidemiology; Chagas Disease - parasitology; Chile - epidemiology; Discrete typing unit (DTU); Dogs; Electrophoresis, Cellulose Acetate; Genetic tag; Genetic Variation - genetics; Human protozoal diseases; Humans; Infectious diseases; Isoenzymes; Isoenzymes - analysis; Linkage Disequilibrium; Medical sciences; Models, Genetic; Paraguay - epidemiology; Parasitic diseases; Phylogeny; Population genetics; Protozoal diseases; Triatoma; Tropical medicine; Trypanosoma cruzi; Trypanosoma cruzi - classification; Trypanosoma cruzi - enzymology; Trypanosoma cruzi - genetics; Trypanosomiasis; South America; Chile; Paraguay; America; Genetic tag; Isoenzymes; Population genetics; Linkage disequilibrium; Trypanosoma cruzi; Discrete typing unit (DTU); Kinetoplastida; Protozoa; Isozyme; Genotype; Genetics; Phylogeny
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/S0001-706X(00)00183-2

Multilocus enzyme electrophoresis (MLEE) of 99 Chilean and 11 Paraguayan stocks of Trypanosoma cruzi, the agent of Chagas disease, was performed for 22 variable genetic loci. As previously shown for this parasite in other geographic areas, a pattern of long-term clonal evolution of T. cruzi genotypes was inferred, both by strong departures of Hardy–Weinberg expectations and high linkage disequilibrium. The presence of the two major phylogenetic lineages that subdivide the species T. cruzi [Tibayrenc, M., 1995. Population genetics of parasitic protozoa and other microorganisms. In: Baker, J.R., Muller, R., Rollinson, D. (Eds.), Advances in Parasitology, vol. 36, Academic Press, New York, pp. 47–115; Souto, R.P., Fernandes, O., Macedo, A.M., Campbell, D.A., Zingales, B., 1996. DNA markers define two major phylogenetic lineages of Trypanosoma cruzi. Mol. Biochem. Parasitol. 83, 141–152], and of several lesser genetic subdivisions (‘discrete typing units’ or DTUs; Tibayrenc, M., 1998a. Genetic epidemiology of parasitic protozoa and other infectious agents: the need for an integrated approach. Int. J. Parasitol. 28 (1), 85–104; Tibayrenc, M., 1998b. Beyond strain typing and molecular epidemiology: integrated genetic epidemiology of infectious diseases. Parasitol. Today 14, 323–329; Tibayrenc, M., 1998c. Integrated genetic epidemiology of infectious diseases: the Chagas model. Mem. Inst. Oswaldo Cruz 93 (5), 577–580), was recorded in this region. Comparison between clonal populations in sylvatic and domestic transmission cycles of the disease in Chile strongly suggests that these two cycles are at least partially separated from one another.