When she was a child “in the land Down Under,” Camilla Whittington’s dad decided that instead of a regular old camping or fishing trip, it would be more fun for them to go look for platypuses. These animals, found only in Australia, are technically mammals, yet they are like no other mammals around – sure, like all mammals, they produce milk for their babies, but they also lay eggs and have a bill like birds do, and, most oddly, the males shoot venom from spurs in their hind legs that causes pain even the strongest painkillers can’t alleviate.
A vet by training, Whittington’s father helped inspire his daughter’s love of science from a young age. “Both my parents encouraged my siblings and I to take an interest in the natural world. I really like the way science explains logically why things are the way they are,” says Whittington.
This passion led her to become a PhD candidate in the Faculty of Veterinary Science at The University of Sydney. Last year, she was awarded a Fulbright Scholarship, a prestigious award set up by US Senator, J. William Fulbright, after World War II, to promote peace and mutual understanding among different nations through educational exchange. Whittington chose to use the year-long scholarship to come to The Genome Institute at Washington University to study the genetics of platypus venom.
There are very few mammals that produce venom. Even in platypuses, only the males make venom, which they use to defend their territories and protect themselves against predators. It’s also very hard to collect platypus venom since it’s mainly produced during the animal’s breeding season, and they don’t breed easily in captivity. Besides that, as Whittington knows from her childhood trips in Australia, it’s quite difficult to catch a wild platypus.
By looking instead at the DNA that makes the venom proteins, Whittington needs a much smaller sample – only a single venom gland from one platypus. This is a far more efficient way to figure out what’s in the venom.
But why study the venom in the first place? “The reason that we’re interested in the venom is that we think there might be some interesting and potentially useful compounds for drug development,” says Whittington.
Platypuses are sometimes called ‘living fossils’ since they are found on the evolutionary tree right between reptiles and mammals that have placentas (like humans). And while platypuses produce milk for their young – like all mammals – they also lay eggs and produce venom like many snakes. Initial studies have shown that platypus venom is very similar in its composition to snake venom, but it’s also clear that snakes and platypuses evolved the ability to make venom by separate pathways, something called convergent evolution. But Whittington points out: “We’re not exactly sure why the venom evolved and that’s another reason why we’re interested in finding out what’s in it.”
Using next generation sequencing technology not available to her in Australia, Whittington is working in the lab of Dr. Wes Warren, Assistant Director at The Genome Institute and Research Associate Professor in the Department of Genetics at Washington University, to study the genes within the platypus DNA that make the components of its venom.
“It’s pretty inspiring to be working with the leaders in the field,” says Whittington who had previously collaborated with Dr. Warren when he led the international effort to sequence the entire platypus genome in 2008. By looking closely at the venom proteins and the genes that make them, Whittington hopes she can find some compounds that could be useful in creating everything from blood pressure medication (like the commonly used ACE inhibitors, which were developed from snake venom) to a new form of painkiller.
Platypus venom causes severe pain that can last for weeks – as seen in those few cases of humans who have been stung. The pain it causes is not even relieved with morphine, a virtual pain cure-all. This could mean that the venom is acting through a new or still unknown pain pathway.
As Whittington finishes her year at The Genome Institute, she is looking forward to returning to Australia, where she plans to finish her doctorate program and further her study of the platypus venom. “I’m hoping that some of the toxins that we identify might improve human health and increase our knowledge about the platypus,” says Whittington.
She also appreciates the extraordinary opportunity her Fulbright Scholarship has given her and the time she has spent here in the United States. “It’s just so inspiring to be working with people who are so passionate about what they’re doing and so committed to bettering our world,” she says.