Dr Michael Gaunt
D Phil (Oxon)
in Genome Parasitology
I have previously held a Wellcome Trust junior research fellowship and RCUK fellow in molecular parasitology and lecturer.
The work is focused on using evolutionary models to understand the molecular epidemiology or "microevolution" and "macroevolution" of the parasite Trypanosoma cruzi the causative agent of South American trypanosomiasis and its insect vector triatomine bugs.
Microevolution: T. cruzi is a zoonose and the genetic relationship, or "population structure", between sylvatic mammals and human reservoir hosts could have important public health implications. We have developed a population genomics method using "microsatellite" genetic markers that provides the most accurate typing tool available for T. cruzi. The application of this tool to field isolates demonstrates T. cruzi has a complex epidemiology. For example, some ecotopes show a close genetic association between sylvatic hosts (rodents) and humans but other ecotopes (opossums) show a mixture of close and distant genetic associations. The microsatellites panel identified multiclonal infections as being much more important than previously thought.
Macroevolution: Our evolutionary studies on triatomine bugs revealed the insect evolved blood-feeding behaviour once and this occurred exactly at the same time as the formation of South America. Finally, theoretical work on evolutionary models reveals that several commonly used assumptions (mutation matrices) may result in erroneous epidemiological inferences. Refining these models provides new epidemiological insights.
Webpages: cluster computing
Examples of research achievements include:
- Gaunt MW, Yeo M, Frame IA, Stothard JR, Carrasco HJ, Taylor MC, Mena SS, Veazey P, Miles GA,Acosta N, de Arias AR, Miles MA. (2003). Mechanism of genetic exchange in American trypanosomes. Nature 421:936-9.
- International Glossina Genome Initiative (2014) Genome sequence of the tsetse fly (Glossina morsitans): vector of African trypanosomiasis. Science 344:380-386
- Llewellyn MS, Rivett-Carnac JB, Fitzpatrick S, Lewis MD, Yeo M, Gaunt MW, Miles MA (2011) Extraordinary Trypanosoma cruzi diversity within single mammalian reservoir hosts implies a mechanism of diversifying selection. Int J Parasitol. 2011 May;41(6):609-14
- Patterson, PS and Gaunt, MW. (2010) Phylogenetic multilocus codon models and molecular clocks reveal the monophyly of haematophagous reduviid bugs and their evolution at the formation of South America. Mol Phyl Evol 56: 608 - 621
- Llewellyn MS, Miles MA, Carrasco HJ, Lewis MD, Yeo M, Vargas J, Torrico F, Diosque P, Valente V, Valente SA, Gaunt MW. (2009) Genome-scale multilocus microsatellite typing of Trypanosoma cruzi discrete typing unit I reveals phylogeographic structure and specific genotypes linked to human infection. PLoS Pathog 5:e1000410
- Llewellyn MS, Lewis MD, Acosta N, Yeo M, Carrasco HJ, Segovia M, Vargas J, Torrico F, Miles MA, Gaunt MW. (2009) Trypanosoma cruzi IIc: phylogenetic and phylogeographic insights from sequence and microsatellite analysis and potential impact on emergent Chagas disease. PLoS Negl Trop Dis 3: e510
- Champion OL, Gaunt MW, Gundogdu O, Elmi A, Witney AA, Hinds J, Dorrell N, Wren BW. (2005) Comparative phylogenomics of the food-borne pathogen Campylobacter jejuni reveals genetic markers predictive of infection source.Proc Natl Acad Sci U S A 102:16043-16048.
- Gaunt MW, Miles MA. (2002). An insect molecular clock dates the origin of the insects and accords with palaeontological and biogeographic landmarks. Mol Biol Evol. 2002 May;19(5):748-61. (reviewed by Science 296: 1767)