Can genome engineering be used to resist diseases currently reducing biodiversity?

This project tests if genome engineering techniques can increase resistance of frogs to chytridiomycosis caused by Bd, which causes extinctions. Whole genome data identified changes enriched in populations frogs surviving extinction level pathogen exposure. These are limited to the MHC genes; they also express different antimicrobial peptides to susceptible frogs.

First X. tropicalis, a Bd-susceptible frog, will be altered to have MHC sequences and antimicrobial peptides typical of a Bd-resistant frog. Genome engineering used at EXRC will alter the MHC genes. To express antimicrobial peptides, we have successfully tested the DNA sequences expressing GFP trangenically in the secretory glands of X. tropicalis. The tools and techniques are in place to enable the student to learn and execute sophisticated genome engineering to produce a frog that we hypothesise is disease resistant.

The project then tests whether the genetically altered frog is resistant; IOZ has facilities and expertise to expose the frogs to pathogens. In addition to comparing the ability of the GA frogs to resist Bd with that of wild-types the reproduction, growth and other traits will be measured, testing whether the genetic alteration has a fitness cost. If the genetically altered animals resist Bd without costs to their fitness, this will act as proof of principle that genetic alteration of animals threatened by a pathogen may be a viable mechanism for retaining biodiversity, albeit as a last resort.