Human cryptosporidiosis is the leading protozoan cause of diarrhoeal mortality worldwide, and most infection is caused by either person to person transmitted Cryptosporidium hominis or the presumptively zoonotic C. parvum. However, C. parvum actually splits into two subclades. One, which we have newly identified as C. parvum anthroponosum is also predominantly spread person to person and shares a subset of loci with C. hominis that are undergoing rapid convergent evolution driven by positive selection. This subspecies predominates in lower-income countries with poor sanitation and in HIV positive individuals, in contrast to higher-income countries where it is rarely evident.
In the course of their studies the student will characterize this new subspecies of parasite providing an annotated reference genome, will evaluate whether its virulence is greater than the zoonotic form, propagating the parasite and genetically transforming it to evaluate the role of the shared loci in adaptation to the human digestive tract.
The student will further develop diagnostic tools to discriminate this group of parasites. The student will be supported by Earlham institute for the genomic aspects of the project and will be affiliated with the EU interreg program H4DC on cryptosporidium which is concerned with production of new drugs and diagnostics for cryptosporidium.
For more information on the project’s supervisor, please visit: Dr K Tyler’s webpage: https://people.uea.ac.uk/en/persons/k-tyler
Type of programme: PhD
Start date of project: October 2020
Mode of study: full time.
Studentship length: Please note 3 year studentships have a (non-funded) 1 year ‘registration only’ period.
Entry requirements: First degree in Natural Sciences, Biological Sciences, Molecular Biology, Biochemistry, Biomedical Science, Medicine or Veterinary Medicine. The standard minimum entry requirement is 2:1.
(i) Evolutionary genomics of anthroponosis in Cryptosporidium
Nader, J., Mathers, T. C., Ward, B. J., Pachebat, J., Swain, M., Robinson, G., Chalmers, R. M., Hunter, P., Van Oosterhout, C. & Tyler, K. 4 Mar 2019 In : Nature Microbiology.
(ii) Anthroponotic transmission of Cryptosporidium parvum predominates in countries with poorer sanitation - a systematic review and meta-analysis
King, P., Tyler, K. M. & Hunter, P. R. 8 Jan 2019 In : Parasites & Vectors. 12, 16
(iii) Prevalence and epidemiology of human Cryptosporidium parvum IIc infections in England and Wales
King, P., Robinson, G., Elwin, K., Tyler, K. M., Hunter, P. R. & Chalmers, R. M. 23 Feb 2017 In : The Lancet. 389, Supplement 1, p. S56 1 p.
(iv) Novel real-time PCR assays for the specific detection of human infective Cryptosporidium species
Bouzid, M., Elwin, K., Nader, J., Chalmers, R., Hunter, P. & Tyler, K. 2016 In : Virulence. 7, 4, p. 395-399 5 p.
(v) Cryptosporidium pathogenicity and virulence
Bouzid, M., Hunter, P., Chalmers, R. M. & Tyler, K. 1 Jan 2013 In : Clinical Microbiology Reviews. 26, 1, p. 115-134