Probst CM, Melo MDFAD, Pavoni DP, Toledo MJDO, Galdino TS, Brandão AA, Britto C, Krieger MA. A new Trypanosoma cruzi genotyping method enables high resolution evolutionary analyses.
Mem Inst Oswaldo Cruz 2021;
116:e200538. [PMID:
34468503 PMCID:
PMC8405150 DOI:
10.1590/0074-02760200538]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 07/22/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND
Trypanosoma cruzi is an important human pathogen in Latin America with nearly seven million people infected. It has a large degree of genetic diversity, classified into six discrete typing units (DTUs), which probably influences its physiological behavior and clinical manifestations. Several genotyping methods are available, with distinct performance on easiness, cost, resolution and applicability; no method excels in all parameters.
OBJECTIVES AND METHODS
To devise a molecular method for T. cruzi genotyping, based on polymerase chain reaction (PCR) amplification of a single target with multiple copies in the nuclear genome by large scale sequencing. We have applied this method to 29 T. cruzi isolates, comprising all described DTUs.
FINDINGS
We were able to classify all samples into sub DTU level with high robustness. Evolutionary relationship between DTUs were ascertained, suggesting that TcIII and TcIV DTUs are non-hybrid, and DTU IV is more similar to the common ancestral.
CONCLUSION
As the TS-LSS method is based on a single PCR reaction, comprising several copies of the target, it is probably useful for clinical samples, when the amount of DNA is a limiting factor. As large scale sequencing systems become more common, the TS-LSS method can be increasingly applied for T. cruzi genotyping.
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