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ABSTRACT The kinetoplastid Protozoa are responsible for devastating diseases1. In the Americas, _Trypanosoma cruzi_ is the agent of Chagas' disease—a widespread disease transmissible

from animals to humans (zoonosis)—which is transmitted by exposure to infected faeces of blood-sucking triatomine bugs2. The presence of genetic exchange in _T. cruzi_ and in _Leishmania_ is

much debated3,4. Here, by producing hybrid clones, we show that _T. cruzi_ has an extant capacity for genetic exchange. The mechanism is unusual and distinct from that proposed for the

African trypanosome, _Trypanosoma brucei_5. Two biological clones6 of _T. cruzi_ were transfected to carry different drug-resistance markers7,8, and were passaged together through the entire

life cycle. Six double-drug-resistant progeny clones, recovered from the mammalian stage of the life cycle, show fusion of parental genotypes, loss of alleles, homologous recombination, and

uniparental inheritance of kinetoplast maxicircle DNA. There are strong genetic parallels between these experimental hybrids and the genotypes among natural isolates of _T. cruzi._ In this

instance, aneuploidy through nuclear hybridization results in recombination across far greater genetic distances than mendelian genetic exchange. This mechanism also parallels genome

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Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS _HOP1_ AND _HAP2_ ARE CONSERVED COMPONENTS OF THE MEIOSIS-RELATED MACHINERY REQUIRED FOR SUCCESSFUL MATING IN _LEISHMANIA_

Article Open access 07 November 2023 COLONIZATION AND GENETIC DIVERSIFICATION PROCESSES OF _LEISHMANIA INFANTUM_ IN THE AMERICAS Article Open access 29 January 2021 A PHASED GENOME ASSEMBLY

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_Proc. Natl Acad. Sci. USA_ 90, 10320–10324 (1993) Article  ADS  CAS  Google Scholar  Download references ACKNOWLEDGEMENTS We thank the Wellcome Trust for financial support, D. Conway for

valuable advice, and S. Wilkinson, S. Obado and J. Kelly for gifts of primers and comments on the manuscript. AUTHOR INFORMATION Author notes * Nidia Acosta & Antonieta Rojas de Arias

Present address: Departamento de Medicina Tropical, Instituto de Investigaciones en Ciencias de la Salud, Universidad Nacional de Asuncion, Asuncion, Paraguay * Iain A. Frame Present

address: The Wellcome Trust, 183 Euston Road, London, NW1 2BE, UK * J. Russell Stothard Present address: Department of Infectious Disease Epidemiology, Imperial College, London, W2 1PG, UK

AUTHORS AND AFFILIATIONS * Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK Michael W. Gaunt, Matthew Yeo, 

Iain A. Frame, Martin C. Taylor, Susana Solis Mena, Paul Veazey, Graham A. J. Miles & Michael A. Miles * Department of Zoology, The Natural History Museum, Cromwell Road, SW7 5BD,

London, UK J. Russell Stothard * Facultad de Medicina, Universidad Central de Venezuela, Caracas, Venezuela Hernan J. Carrasco Authors * Michael W. Gaunt View author publications You can

also search for this author inPubMed Google Scholar * Matthew Yeo View author publications You can also search for this author inPubMed Google Scholar * Iain A. Frame View author

publications You can also search for this author inPubMed Google Scholar * J. Russell Stothard View author publications You can also search for this author inPubMed Google Scholar * Hernan

J. Carrasco View author publications You can also search for this author inPubMed Google Scholar * Martin C. Taylor View author publications You can also search for this author inPubMed 

Google Scholar * Susana Solis Mena View author publications You can also search for this author inPubMed Google Scholar * Paul Veazey View author publications You can also search for this

author inPubMed Google Scholar * Graham A. J. Miles View author publications You can also search for this author inPubMed Google Scholar * Nidia Acosta View author publications You can also

search for this author inPubMed Google Scholar * Antonieta Rojas de Arias View author publications You can also search for this author inPubMed Google Scholar * Michael A. Miles View author

publications You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to Michael A. Miles. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare

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ARTICLE CITE THIS ARTICLE Gaunt, M., Yeo, M., Frame, I. _et al._ Mechanism of genetic exchange in American trypanosomes. _Nature_ 421, 936–939 (2003). https://doi.org/10.1038/nature01438

Download citation * Received: 11 October 2002 * Accepted: 14 January 2003 * Issue Date: 27 February 2003 * DOI: https://doi.org/10.1038/nature01438 SHARE THIS ARTICLE Anyone you share the

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