So what is eDNA?

---

As you probably learnt at school, DNA, or deoxyribonucleic acid, is the defining material in an organism which gives us the blue print for life. Each organism is different, with the DNA holding the information for how it is created. An important property of DNA is that it can replicate, or make copies of  itself. Each strand of DNA in the double helix can serve as a pattern  for duplicating the DNA sequence of an organism. This is critical when cells  divide because each new cell needs to have an exact copy of the DNA  present in the old cell. 

Our analytical teams take advantage of this process, artificially replicating the available DNA strands within our environmental sample and identifying our target DNA.

Environmental DNA (eDNA) presents the remnants of DNA released to the environment by an organism from shedding (skin, hair, scales), mucous release or bodily excretion. This material can be obtained from environmental samples (water, sediment, soil etc.) and analysed in the laboratory to identify the organisms that it originated from. Overtime, eDNA is broken down by environmental processes. Water samples may last from hour to weeks, while sediments and soils may persist much longer. 

In 1977, Frederick Sanger, Allan Maxam, and Walter Gilbert developed  methods to sequence DNA. This was supplemented in 1983 by Kary Mullis,  who invented the polymerase chain reaction (PCR) to amplify DNA.  Together these methods paved the way for sequencing of the human genome  which began in 1990 and was completed 13 years later.

The investigation into eDNA has been more recent. Commencing in 2008, we have experienced a little over 10 years of research, with a steady increase in the volume of dedicated research papers. Over this period we have also seen the development of next generation sequencing, and the application of meta-barcoding and the growth of bioinformatics required to process the huge volumes of data being developed.

eDNA is a developing field. As the techniques continue to mature and clients begin to come to terms with its applications, eDNA is providing a new way of looking at our natural world. Data which was once out of reach can now be collected efficiently, safely and in a timely manner, improving management decisions and supporting sustainability more than ever.