In a significant breakthrough for conservation biology, researchers have successfully sequenced the complete genome of the Southern Corroboree Frog (Pseudophryne corroboree), one of Australia’s most critically endangered and visually distinctive amphibians. The study represents a major milestone in efforts to preserve the species, which is currently considered ‘functionally extinct’ in the wild due to the devastating impact of chytridiomycosis, and was led by scientists at the University of Melbourne and published in Wellcome Open Research.
Chytridiomycosis, a lethal fungal disease caused by the chytrid fungus (Batrachochytrium dendrobatidis), has decimated wild populations of the Southern Corroboree Frog. At present, no viable populations exist in their natural habitat, and the species survives only through captive breeding programs maintained by institutions such as Melbourne Zoo, Healesville Sanctuary, and the Taronga Conservation Society. Given this precarious status, the genome sequencing provides a vital tool in the campaign to reintroduce the frogs to their native alpine environment in the Snowy Mountains of New South Wales.
Dr. Tiffany Kosch, lead author and conservation geneticist at the University of Melbourne, stated that the genome sequencing process took nearly ten years to complete. She highlighted the complexity of the task, noting that the Southern Corroboree Frog possesses an unusually large genome—over three times the size of the human genome. “This is the first time the complete genome of this species has been mapped,” Dr. Kosch explained. “The process was incredibly challenging due to the genome’s sheer size and structure.”
One of the most intriguing findings from the research was the discovery that more than 80 percent of the frog’s genome consists of non-coding DNA—sequences that do not directly translate into proteins. The function of this vast amount of non-coding material remains uncertain, but scientists believe it may play an important role in gene regulation and species adaptation, especially in amphibians.
The genome sequencing was conducted in collaboration with the Vertebrate Genomes Project at Rockefeller University, USA, and the New South Wales Department of Climate Change, Energy, the Environment, and Water. Tissue samples, including kidney and liver, were obtained from a male frog bred in captivity, forming the basis for the high-quality genomic data produced.
According to Dr. Kosch, sequencing the genome marks a crucial first step in a larger conservation strategy aimed at restoring the species to the wild. “With the genetic blueprint now available, we can begin identifying the genes that influence resistance or susceptibility to the chytrid fungus,” she said. “This knowledge will enable us to selectively breed individuals that have a natural resilience to the disease, increasing the likelihood of successful reintroductions without ongoing human dependency.”
Beyond its significance for the Southern Corroboree Frog, this research also holds potential benefits for amphibian conservation worldwide. Chytridiomycosis has contributed to population declines in hundreds of amphibian species globally. By comparing the genome of the Southern Corroboree Frog with those of other species, researchers hope to uncover broader genetic patterns of resistance and vulnerability. These insights could help guide conservation strategies and breeding programs for other at-risk amphibians.
The pioneering work not only advances the field of amphibian genomics but also strengthens the foundation for ecological restoration and biodiversity protection. As Dr. Kosch emphasized, the ultimate goal is to see the Southern Corroboree Frog thriving once again in its natural environment—free from the shadow of extinction and no longer reliant on human care for survival.
