UQ School of Biological Sciences Associate Professor Bryan Grieg Fry and colleagues have published research this week which shows pythons are a surprising potential source of false-positives in snake venom detection kits.
Associate Professor Fry said that although pythons were non-venomous, “relic” traces of venom in their saliva could trigger the extremely sensitive snake venom detection kits.
“Using antivenom to treat patients with python bite injuries could potentially trigger life-threatening allergies to the antivenom, without the benefit of curing a snake bite,” he said.
“Unnecessary use of the antivenom reduces stocks available for patients who actually need it.”
Associate Professor Fry said this highlighted the decisions about administering antivenom should be based on the severity of clinical symptoms.
“A venom detection kit should be used to ensure that the appropriate antivenom is given, but it is sometimes mistakenly used as a diagnosis of snakebite by itself,” he said.
“All snakes evolved from a common ancestor that was a venomous lizard.”
“Evolution is like a crime scene, there is always evidence to be found if the scientist is a good enough detective.”
Associate Professor Fry said snakes had varying potency of ‘venomosity’ ranging from those capable of life-threatening bites, such as cobras or taipans, to those that have lost almost all their venom, such as egg-eating sea snakes and pythons.
Previous studies that found python saliva could cross-react in the snake venom detection kit were dismissed as an anomaly.
Associate Professor Fry’s study found that a python’s oral glands predominantly secrete mucous to aid in swallowing large prey, but there are also traces of relic venom.
“The extremely low levels of toxins in their mouths have no effect on prey or bitten humans, however in forensic-level diagnostic tools like the snake venom detection kit, they cross-react and give a false positive.”
“These novel molecules represent an untapped resource for biodiscovery,” Associate Professor Fry said.
“We have found that the low level of ancient toxins still secreted in these glands includes novel compounds quite different than those from their well-studied cousins like rattlesnakes or mambas.”
“In addition to providing insights regarding how the snake venom system evolved, these results reinforce the value of studying a wide range of snakes, as novel compounds with significant potential for use in drug design and development may be uncovered in the most unlikely of places,” he said.
The study findings are published in Molecular & Cellular Proteomics.
About the School of Biological Sciences
Through research undertaken in the School, UQ has been ranked by the 2012 National Taiwan University Rankings in the top five universities globally for research in ecology and environmental biology and in the top 18 universities globally for plant and animal biology. The UQ School of Biological Sciences attracts researchers of world standing in a range of disciplines, with international leaders in many diverse fields. Our work spans the scales of biological organisation, from molecules and cells to organisms, populations, species and communities. With more than 150 researchers working in evolution, global change biology, ecology, aquaculture, animal behaviour, physiology, entomology, zoology, botany, genomics, development and conservation biology, our researchers and graduate scientists are well-equipped to make a real difference in contributing to solving global problems.