Dr Giana Gomes shared on eDNA with S.E.A. Aquarium team members, conducted experiment | S.E.A. Aquarium at Resorts World Sentosa

As part of our mission to empower team members with new and in-depth marine life knowledge, Guardians of the S.E.A.A. organised a second in-house sharing session on 13 November 2018. This time, we invited Dr. Giana Gomes from James Cook University Singapore to talk about environmental DNA (eDNA) and highlight its importance and relevance to aquariums.

About 40 team members attended the sharing session.

Dr Gomes is an aquaculture veterinarian researcher with 15 years of experience in aquatic animal health. Currently, her R&D focuses on early identification of disease within aquaculture farms using eDNA techniques and water quality monitoring (environmental sensing) associated with microbiome investigation.

She explained how eDNA research is similar to crime scene investigation, where samples such as skin mucus, excretions and faeces are collected to detect the presence of certain species. As such, eDNA has many useful applications, such as searching for endangered species, microbes detection and species distribution determination.

In the case of aquarium and aquaculture, eDNA can help to minimise the risk of  disease outbreak and improve survival rates. All these knowledge comes in especially handy for our curatorial team members, complementing their husbandry know-how and experience.

Dr Giana Gomes shared a case study where a barramundi farm in Australia used eDNA to successfully minimise parasite outbreak. They found the correlation between the level of parasites and factors such as rainfall, temperature and fish size. With the data, they relooked at their husbandry practices to significantly reduce risks of parasite outbreak.
Several attendees posed questions such as how eDNA is still relevant in the context of an open ocean.

To help attendees better understand eDNA, Dr Gomes got them to conduct an experiment where they extracted strawberry DNA on the spot.

Crushing the strawberries breaks open the cells and releases the nuclei where the DNA is.
When combined with the extraction buffer, the nuclear membrane will break open and release the DNA into the solution.
Finally, an equal volume of ice-cold ethanol is layered on top of the strawberry solution in the test tube.
DNA is insoluble in alcohol, so it precipitates.
This is the precipitation of strawberry DNA – long, thread-like DNA molecules at the interface of the alcohol and DNA solution.
Dr Gomes went around the room to answer questions and share her experience.
Jim Hudson, Senior Manager of Conservation, presenting a certificate of appreciation to Dr Giana Gomes.

Next year, Guardians of the S.E.A.A. will continue to invite subject matter experts to share their knowledge and experience with S.E.A. Aquarium team members. Find out more about what else Guardians of the S.E.A.A. does.