We recovered DNA matching the people, the animal patient and common animal viruses present at the time of collection. People who were present in the room gave us permission to take samples from the air.

We also collected air samples from a room in our wildlife veterinary hospital in Florida. We found human DNA everywhere but in the remote mountain tributary where the river starts, far from human habitation. We also tested the technique in Ireland, tracing along a river that winds from a remote mountaintop, through small rural villages and into the sea at a larger town of 13,000 inhabitants. We found human DNA in all of those locations except the remote island, and these samples were high quality enough for analysis and sequencing.

To figure this out, we took samples from a variety of locations in Florida, including the ocean and rivers in urban and rural areas, sand from isolated beaches and a remote island never usually visited by people. What we didn’t know was just how informative the human DNA we could extract would be. Our team suspected that the sand and water samples we were using to study sea turtles would also contain DNA from a number of other species – including, of course, humans. Genetic sequencing technology used to decode DNA has improved rapidly in recent years, and it is now possible to easily sequence the DNA of every organism in a sample from the environment. Unlike blood or skin sampling, collecting eDNA causes no stress to the animal. Scooping a liter of water from the tank of a recovering sea turtle under veterinary care equally provides a wealth of genetic information for research. Sand scooped from their tracks contains enough DNA to provide valuable insights into the turtles and the chelonid herpesviruses and fibropapillomatosis tumors that afflict them. Tiny hatchling sea turtles shed DNA as they crawl along the beach on their way to the ocean shortly after they are born. Our team uses environmental DNA to study endangered sea turtles and the viral tumors to which they are susceptible. And as our team of geneticists, ecologists and marine biologists in the Duffy Lab at the University of Florida found, signs of human life can be found everywhere but in the most isolated locations. However, humans also shed, cough and flush DNA into their surrounding environment. Researchers using eDNA tools usually focus only on the species they’re studying and disregard DNA from other species. Tracking rare or elusive endangered species through their eDNA has been a boon to researchers, since traditional monitoring methods such as observation or trapping can be difficult, often unsuccessful and intrusive to the species of interest.

For the last couple of decades, scientists have been able to collect and sequence eDNA from soil or water samples to monitor biodiversity, wildlife populations and disease-causing pathogens. The water, soil and even the air contain microscopic particles of biological material from living organisms.ĭNA that an organism has shed into the environment is known as environmental DNA, or eDNA. However, all living things, including animals, plants and microbes, constantly shed DNA. Typically, medical practitioners and researchers obtain human DNA through direct sampling, such as blood tests, swabs or biopsies. Because each person has a unique genetic code, DNA can be used to identify individual people. Human DNA can be sequenced from small amounts of water, sand and air in the environment to potentially extract identifiable information like genetic lineage, gender, and health risks, according to our new research.Įvery cell of the body contains DNA. The following essay is reprinted with permission from The Conversation, an online publication covering the latest research.

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