New guidelines support best practices in environmental DNA testing

Every living organism sheds its DNA into the environment, leaving behind an invisible record of its presence.

However, scientists have found ways to amplify this environmental DNA (eDNA) from water, soil and other environmental samples, allowing them to identify who the DNA belonged to.

These molecular surveillance tools have a range of applications including detecting pests or threatened species and monitoring biodiversity.

Scientists from the Australian Antarctic Division, including Dr. Anna MacDonald, Dr. Leonie Suter and Dr. Laurence Clarke, use eDNA methods to identify the presence of one or more Antarctic organisms, such as krill and fish, in seawater, predatory feces, and other environmental samples. Their work provides new insights into the role of Antarctic krill in the Southern Ocean ecosystem, its interactions with predators, and its preferred habitat.

The trio, along with scientists from CSIRO, the University of Canberra and a number of other Australian and New Zealand research institutions, recently published two best practice guidelines for Australian and New Zealand eDNA researchers and testing agencies, and an overview of the guidelines, in the journal environmental DNA.

The guidelines aim to ensure methods are standardized across users to ensure quality and maintain confidence in eDNA-based results.

“eDNA methods have evolved from simple research tools to key components of surveillance programs in both government and industry,” said Dr. MacDonald. “This means that we need to ensure that eDNA methods are suitable for surveillance purposes. Monitoring programs can run for many years. So in order to create long-term datasets and compare results across time or locations, we need to use reliable, standardized methods.

“These new guidelines will ensure that environmental managers have solid scientific evidence to support their decision-making. The guidelines will also support the evaluation of the best eDNA methods to use in situations where inaccurate or incorrect results could have financial, ethical or legal consequences, such as: B. Biosecurity.”

The Guide to Developing the Environmental DNA Protocol for Biomonitoring provides minimum standards for eDNA projects, from ethical considerations and experimental design to interpretation and communication of results. The Environmental DNA Test Validation Guidelines describe steps to be followed in the development of tests for the detection of single species or multiple species.

The publication of the overview paper coincides with the inaugural Australia-New Zealand eDNA Conference, 14-17 February 2023 in Hobart.

The guidelines were an initiative of the Australian Government’s Department of Agriculture, Fisheries and Forestry led by the Southern eDNA Society in consultation with eDNA experts and end users.