Museum's "Frozen Zoo" May Join Global Tissue Network

22 August 2012

The South Australian Museum could soon join a new international "bio-bank" of institutions that look after valuable tissue samples.

The Museum is custodian to the Australian Biological Tissue Collection – the largest in the Southern Hemisphere – with a jaw-dropping nearly 125,000 samples of animals, fish, birds and plants kept in giant freezers at the Adelaide site.

The Global Genome Biodiversity Network (GGBN) is forming a pool of key biorepositories and research organisations with the intention of governing the exchange of samples, technology and information.

The Museum will be put forward by GGNB's International Steering Committee Members as a potential member. The move is a huge coup in building international recognition for our vital research collection.

The miniscule tissues at the South Australian Museum are literally scientific treasures.

The samples have helped convict criminals in Australian court cases, identify illegal imports, helped scientists across the globe study biodiversity and allowed local researchers to discover and identify new species.

Many of the tissues are from species which are now extinct, such as the Southern Gastric Brooding Frog from southern Queensland, and the Long-eared Mouse from South Australia. Samples can be taken from any part of the animal.

Tissue Collection Manager Leanne Wheaton says, "Whenever I tell people about what I do, they are amazed that the Museum holds such an extensive tissue collection and that it is accessed by researchers for so many different projects. In the last few months, I have sent out tissues to researchers at Oxford University, UCLA, the American Museum of Natural History in New York, Japanese Customs and many of the interstate Australian universities and museums."

The South Australian Museum's Evolutionary Biology Unit (EBU) maintains the tissue stores. The collection is priceless because of the effort it takes to gather the samples and because many of the samples are now irreplaceable.

"There's everything from deep sea invertebrates to insects to fish, to mammals and reptiles, birds and bears. There are lots of really important New Guinean materials from early field trips by Museum scientists – many of those species have not even been described yet. That material is irreplaceable because it was collected from out of the way places you'd probably never get to again," Ms Wheaton says.

EBU head Professor Steve Donnellan was one of the first staff members to look after the collection at the Museum. He says "in the early 1980s the South Australian Environment Department, the Museum and the Herbarium started a statewide biodiversity survey which included sampling tissues for DNA analysis, which as far as I know, is unique in Australia and not replicated in many other parts of the world. It's for that reason that so many tissues started to accumulate in our freezers."

While the collection had humble beginnings with a handful of samples in a single freezer back in 1982, it now requires a bank of fourteen -80°C ultra-cold freezers to keep the Museum's "frozen zoo".

For three decades, the Museum has engaged scientists to do genetic work and they have added to the collection through specific research projects. Now, more than 100 researchers use tissues from the central collection.

"In the future, animal populations will shift their ranges in response to climate change and we'd like to know how their genetic profile changes in response as well. You can only do that when you have samples from the time when climate change started to have an impact," says Professor Donnellan.

The tissue samples have even helped solve crimes.

"We helped the Fisheries Department in the '90s," says Professor Donnellan. "They were prosecuting some abalone poachers and had taken some traces of what they thought could be abalone from a plastic bin as part of the evidence. Abalone poaching is a big organised crime enterprise not only in Australia but around the globe. We helped them out by showing that the traces were indeed blacklip abalone, causing the defendants to take a plea and thus avoiding an expensive trial."

"In these court cases that require identification from DNA sequences, you actually need to have sequences from reference samples to compare with. If you don't, you can't be unequivocal that it isn't something else and the lawyers will home in on that. The tissue collection is such an important resource in providing quick access to these vital reference samples."

When Museum scientists and other researchers discovered a new species of large venomous snake in the central Australian deserts in 2006, tissues from the collection were used to do DNA analysis and conclude that the snake was the third species of Taipan. Its relatives are among the most deadly species of snake known to man. Scientists interested in the properties of snake venom have since captured live specimens to assess the venom's clinical and medical worth.

The South Australian Museum is careful who it allows to use the tissues. Since each sample is reduced every time a researcher needs a piece cut off, applicants always have to prove the value of their project before they're allowed access. A tiny sliver the size of a quarter of a grain of rice is all that is allowed out of the collection!

However, the flip side is that as each researcher discovers something new about an animal's DNA sequences, it adds value to the collection and showcases the value of the South Australian Museum's efforts to preserve these important samples.