Genomics and High-Resolution Typing Confirm Predominant Clonal Evolution Down to a Microevolutionary Scale in <i>Trypanosoma cruzi</i>

• Main Authors: Michel Tibayrenc, Francisco J. Ayala
• Format: Article
• Language: English
• Published: MDPI AG 2020-05-01
• Series: Pathogens
• Subjects: Chagas disease; parasitic protozoa; clonality threshold; genetic recombination; phylogenetic signal; Russian doll pattern
• Online Access: https://www.mdpi.com/2076-0817/9/5/356

<i>Trypanosoma cruzi</i>, the agent of Chagas disease, is a paradigmatic case of the predominant clonal evolution (PCE) model, which states that the impact of genetic recombination in pathogens’ natural populations is not sufficient to suppress a persistent phylogenetic signal at all evolutionary scales. In spite of indications for occasional recombination and meiosis, recent genomics and high-resolution typing data in <i>T. cruzi</i> reject the counterproposal that PCE does not operate at lower evolutionary scales, within the evolutionary units (=near-clades) that subdivide the species. Evolutionary patterns in the agent of Chagas disease at micro- and macroevolutionary scales are strikingly similar (“Russian doll pattern”), suggesting gradual, rather than saltatory evolution.