It is now possible to extract human DNA from the air or from a footprint on the beach. What effects can it have?

() — Footprints on a beach. Air breathed in a crowded room. Ocean water.

Scientists have been able to collect and analyze detailed genetic data of human DNA from all of these locations, raising complex ethical questions about consent, privacy, and security when it comes to our biological information.

Researchers at the University of Florida, using environmental DNA found in the sand to study endangered sea turtles, claimed that the DNA was of such high quality that they could identify disease-associated mutations and determine the genetic ancestry of the populations that lived in it. near.

They were also able to match the genetic information with that of individual volunteer participants to recover their DNA as part of the research published Monday in the scientific journal Nature Ecology & Evolution.

The team collects water samples in St. Augustine, Florida. Credit: Todd Osbourne

“All of this very personal, ancestral and health-related data is freely available in the environment and it’s just hanging in the air right now,” said David Duffy, professor of Wildlife Disease Genomics at the University of Florida. .

The researchers have been able to obtain environmental DNA from cores of air, soil, sediment, water, permafrost, snow and ice, and the techniques are used primarily to help track and protect endangered animals.

Human DNA that has leaked into the environment through our saliva, skin, sweat, and blood could be used to help find missing persons, assist in forensic investigations to solve crimes, locate sites of archaeological significance, and for security surveillance. health through DNA found in wastewater, says the study.

However, the ability to capture human DNA from the environment could have a number of unintended and malicious consequences, they added. These include breach of privacy, location tracking, data collection, and genetic surveillance of individuals or groups. In addition, it could pose ethical obstacles when it comes to approving studies on wildlife.

Matthias Wienroth, Principal Investigator of the Social and Ethical Aspects of Genetics in Forensics, Surveillance and Human Health at Northumbria University, UK, said the scientists involved in the study had taken “very seriously the ethical aspects of their work” and “identified some key issues that are likely to arise from their findings.”

“It is important to preserve human autonomy, dignity and the right to self-determination over personal data. This is difficult if you cannot ask permission from people whose DNA may be picked up in the environment, because there is probably no way around DNA is lost to the environment through the skin, hair and breath,” Wienroth, who was not involved in the research, said by email.

He underscored the need to develop and deploy foresight in genetic and genomics research: “A key issue is that these serendipitous DNA finds can make it into databases that can be compared with user data in other genetic databases, undermining thus the informed consent and even the confidentiality of the client”.

Human DNA in water, sand and air

No human DNA was found in a sample taken from the top of this hill in Wicklow, Ireland. Credit: Dr. David Duffy, University of Florida

The team from the University of Florida’s Whitney Laboratory of Marine Bioscience and Sea Turtle Hospital was using environmental DNA, recovered from turtle tracks made in the sand, to study endangered green sea turtles and viral cancers at the that they are susceptible, when they realized they were also collecting human DNA from the sand and in the ocean and rivers surrounding the lab.

They called this information “human genetic bycatch” and decided to study the phenomenon further.

In addition to samples from subtropical Florida, Duffy tested water from the Avoca River in County Wicklow in temperate Ireland and found human DNA as it passed through the town of Arklow, though not in the upper reaches of the river. where there were no human settlements.

They also recovered DNA from footprints made in the sand by four volunteers. With their permission, they were able to sequence part of the participants’ genome. Next, the researchers took air samples from a 3,000-square-foot room in an animal clinic where six people went about their daily routine. The team recovered DNA that matched that of volunteer staff, animal patients, and common animal viruses.

From the genetic information collected, the scientists were able to identify genetic variants associated with the European and Latino populations, as well as variations associated with a number of disorders and diseases such as autism, diabetes, eye disease, cancer, and heart disease.

Filters prepared for environmental DNA extraction. Credit: Dr. David Duffy, University of Florida

“These sequences recovered both the nuclear and mitochondrial regions of the human genome, which means we can easily determine whether a male or female (were) walking in the sun or (their) presence in a room depending on whether or not we sequenced the chromosome. X or Y,” Duffy explained at a press conference.

“Using the mitochondrial genome, we were able to investigate the genetic ancestry of our samples.”

Yves Moreau, a professor at the University of Leuven, Belgium, who studies artificial intelligence and genetics and has shed light on the minority DNA sampling Tibetan and Uighur by China, said that while it was possible to imagine a scenario where “a mafia or dictatorship would track down a protected witness or political refugee” using wastewater sequencing, it was still “a bit far-fetched.”

“We need a political debate about privacy expectations in public space, particularly for DNA. We cannot avoid dumping DNA in public space,” Moreau, who was not involved in this study, said by email.

“However, we must not panic, and I always fear that precautions will stall the investigation. It is a delicate balance to find.”