Whole genome sequencing of Trypanosoma cruzi field isolates reveals extensive genomic variability and complex aneuploidy patterns within TcII DTU 06 Biological Sciences 0604 Genetics

João Luís Reis-Cunha, Rodrigo P. Baptista, Gabriela F. Rodrigues-Luiz, Anderson Coqueiro-Dos-Santos, Hugo O. Valdivia, Laila Viana De Almeida, Mariana Santos Cardoso, Daniella Alchaar D'Ávila, Fernando Hugo Cunha Dias, Ricardo Toshio Fujiwara, Lúcia M.C. Galvão, Egler Chiari, Gustavo Coutinho Cerqueira, Daniella C. Bartholomeu

Research output: Contribution to journalArticlepeer-review

Abstract

Background: Trypanosoma cruzi, the etiologic agent of Chagas disease, is currently divided into six discrete typing units (DTUs), named TcI-TcVI. TcII is among the major DTUs enrolled in human infections in South America southern cone, where it is associated with severe cardiac and digestive symptoms. Despite the importance of TcII in Chagas disease epidemiology and pathology, so far, no genome-wide comparisons of the mitochondrial and nuclear genomes of TcII field isolates have been performed to track the variability and evolution of this DTU in endemic regions. Results: In the present work, we have sequenced and compared the whole nuclear and mitochondrial genomes of seven TcII strains isolated from chagasic patients from the central and northeastern regions of Minas Gerais, Brazil, revealing an extensive genetic variability within this DTU. A comparison of the phylogeny based on the nuclear or mitochondrial genomes revealed that the majority of branches were shared by both sequences. The subtle divergences in the branches are probably consequence of mitochondrial introgression events between TcII strains. Two T. cruzi strains isolated from patients living in the central region of Minas Gerais, S15 and S162a, were clustered in the nuclear and mitochondrial phylogeny analysis. These two strains were isolated from the other five by the Espinhaço Mountains, a geographic barrier that could have restricted the traffic of insect vectors during T. cruzi evolution in the Minas Gerais state. Finally, the presence of aneuploidies was evaluated, revealing that all seven TcII strains have a different pattern of chromosomal duplication/loss. Conclusions: Analysis of genomic variability and aneuploidies suggests that there is significant genomic variability within Minas Gerais TcII strains, which could be exploited by the parasite to allow rapid selection of favorable phenotypes. Also, the aneuploidy patterns vary among T. cruzi strains and does not correlate with the nuclear phylogeny, suggesting that chromosomal duplication/loss are recent and frequent events in the parasite evolution.

Original languageEnglish (US)
Article number816
JournalBMC genomics
Volume19
Issue number1
DOIs
StatePublished - Nov 13 2018

Keywords

  • Copy number variation
  • Field isolates
  • Genomic variability
  • Ploidy
  • TcII
  • Trypanosoma cruzi

ASJC Scopus subject areas

  • Biotechnology
  • Genetics

Fingerprint

Dive into the research topics of 'Whole genome sequencing of Trypanosoma cruzi field isolates reveals extensive genomic variability and complex aneuploidy patterns within TcII DTU 06 Biological Sciences 0604 Genetics'. Together they form a unique fingerprint.

Cite this