What is eDNA?

Sally Le Page has spent the last couple of weeks with Naked Scientist Phil Sansom digging deep into the exciting new world of environmental DNA, or eDNA for short. It's the same technology you might have heard being used during the pandemic to detect COVID DNA in sewage water. But, what actually is this technology? Sally spoke to Beth Clare from York University in Toronto...

Beth - Environmental DNA is any DNA you collect from an animal that you didn't get directly from that animal. So, some people would argue it has to be effectively naked DNA that's out of itself, floating around in the environment. Other people would say, well, it's just sort of anything. It’s bits of sloughed off cells and bits of hair that are out there that you collect, but you don't actually see the animal when you get them. You're just taking them out of some substance, like water or soil.

Sally - But, why would you want to get the DNA from the environment, the water, the soil, and not just take the DNA directly from the animal?

Beth - Well, because some animals are hard to find. So, it's a good non-invasive way of collecting things from an animal that you can't get, or you shouldn't get in contact with. So, it's a way of collecting things that doesn't cause you to interact specifically with the individual that you are targeting.

Sally - When you say you shouldn't get in contact with the animal, what are we talking about here?

Beth - Well, something that's really sensitive, something that is highly endangered. You don't want to interfere with it in any way that might cause harm or cause stress to that animal. It's a really good non-invasive technique.