Introduction
Genomics is currently undergoing a revolution brought about by the advent of high-throughput parallel sequencing and powerful cytogenetic techniques such as fluorescent in-situ hybridization (FISH) and comparative genomic hybridization (CGH). This has opened new opportunities to study non-model organisms, such as reptiles and amphibians, in ways that were previously restricted to human and mouse.
Of special interest to our lab is the comparative genomics of sex determination in reptiles. Sex determination has been a topic of speculation and rigorous inquiry since the time of Aristotle, and remains a hot topic today because of its intrinsic interest as a fundamental biological process, and because greater understanding brings benefits for human health. The Reptile Genomics Team at the University of Canberra is using frontier DNA technologies to probe the astonishingly diverse mechanisms of sex determination in reptiles.
Particularly mysterious is that sex is determined by genes in some animals, and by temperature in others. We are studying closely related dragon lizards which determine sex via genes (GSD) or temperature (TSD) or a combination of the two. Our approach is to use novel genetic, molecular and cytological approaches to discover genes and chromosomes that control sex determination in the GSD species, and explore their homologues in the TSD species. We expect this study will provide new insights to mechanisms of sex determination in all vertebrates, and demonstrate how genes and the environment interact to control the process.
In a nutshell, we aim to investigate homology in sex chromosomes across target reptile groups and to collaborate with others in Japan and the US in mapping homology across amniotes generally. We plan also to discover the molecular basis of sex determination in our model reptile species, the Central Bearded Dragon, and then expand the focus to other closely related Australian reptiles with genetic sex determination (GSD) and temperature-dependent sex determination (TSD). Our approach is to investigate the tractable mechanisms in a GSD reptile, then to translate the tools and markers to investigation of TSD reptiles. Finally, we plan to develop computational models of evolutionary transitions between modes of sex determination (XX/XY, ZZ/ZW, TSD).
This work is yielding fundamental insights to sex determination in reptiles, of intrinsic interest in itself. Additionally, the understanding we gain of the underlying diversity in mechanisms of reptile sex determination will be central to a deeper understanding of how reptiles, particularly those with TSD, can respond to climate change through phenotypic and evolutionary change.
Resources
Our work is conducted through the well resourced Wildlife Genetics Facility at the Institute for Applied Ecology at the University of Canberra. The Pogona vitticeps BAC library is held in the Wildlife Genetics Laboratory at the University of Canberra, as an invaluable resource. We are a formal partner in and have access to the high throughput parallel sequencing facility at the Australian National University, with capacity for analyzing data onsite.
Interested in joining our team?
If you are a prospective postgraduate student or prospective postdoctoral fellow with strong interests in reptile or amphibian genomics or sex determination, we may be the home for you. We are always interested in new additions to our team, particularly if you have a strong academic record, enjoy a demanding but productive and collegial work environment, and are interested in wildlife genetics or genomics.
Domestic students with First class Honours are guaranteed a PhD Scholarship. Top-up Scholarships are also available.
