A new study shows that we leave DNA in the entire place, including in the air. This is the first time researchers have collected animal DNA from pure air samples.
This DNA The phenomenon that humans or other organisms fall into the environment is called environmental DNA (eDNA). It is quite common to collect eDNA from the water to understand the species that live there, but until now, no one has tried to collect animal eDNA from the air.
Elizabeth Clare, an ecologist and research writer at Queen Mary University of London, said: “What we want to know is whether we can filter eDNA from the air to track the presence of terrestrial animals.”
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As a proof-of-concept experiment, Clare and her colleagues tried to collect DNA from the air in an animal facility equipped with model organisms. Naked mole rat. The researchers detected human and mole rat DNA from the squirrel cage and containment chamber.
Matthew Barnes, an ecologist at Texas Tech University who was not involved in the new study, said: “The proof that the DNA of relatively large animals can also be detected from air samples has greatly expanded the machine. Contains the potential of eDNA analysis.”
Barnes said that in the past decade, the collection and analysis of eDNA for research and management of plant and animal populations began to rise. “The analogy I use is like a detective at a crime scene, finding a cigarette butt and then using it to wipe the DNA to put the criminal at the crime scene. We use eDNA to do this. In addition to looking for criminals, we are looking for Rare or elusive species,” Barnes said. He said that the species may be endangered, or a new invasive species in the environment.
Before conducting this study, some researchers had collected plant DNA from the air, but most of the experiments involved “plants that are expected to deliberately release DNA plumes into the air in the form of pollen and scattered seeds.” Ens said. On the other hand, animals do not. “We don’t know if this will work,” Claire told Live Science.
However, although animals do not shoot pollen spores into the air, they do release DNA in the form of saliva and dead skin cells. To see if animal eDNA from these sources could be collected, Clare and her colleagues evacuated air from the shell of naked mole rats and the room where the shell is located through a vacuum cleaner similar to the HEPA filter commonly found in heating and ventilation systems. The researchers then extracted the DNA from the filter and sequenced it. To identify the source of the DNA, the researchers compared these sequences with reference sequences in the database.
Claire told Live Science that the discovery of human DNA in animal enclosures surprised researchers. However, Claire said that considering the care of the rat by humans, it makes sense in retrospect.
Barnes said the presence of human DNA in almost every sample in the study was a “major obstacle.” On the one hand, it is encouraging to show that the detection method is sensitive, Barnes said. But he added: “But this may also indicate that airborne samples are particularly vulnerable to contamination by the research team’s DNA, especially when mammals are the target of analysis.”
To avoid this contamination, researchers may have to use clean room technologies (such as air filters, dressing gowns, and hair nets) to avoid adding their DNA to the environment under study or DNA samples being used.
In the future, scientists hope to use this technology to monitor animal species in hard-to-reach homes. Claire told Live Science: “I can imagine putting a tube in a perch or in a tunnel system and sucking air out of the system without having to try to track the animal to find the substance in it.”
This may also be a good way to detect rare species that exist in a given environment, such as Endangered species, She added. Barnes said that it can help discover a species without interacting with it, which may have advantages. “[The method might] Let us have the opportunity to investigate organic matter without having to deal with them and put pressure on them. “
Whether eDNA analysis can allow scientists to estimate populations or the number of animals inhabited is a subject of debate, but Clare said that she does not think it is beneficial. She said: “There are too many steps in the procedure, which may cause changes in the amount of DNA you collect.”
Claire said in the video abstract that now Claire and his colleagues are studying how far airDNA can spread and how the size of the space affects how much eDNA can be detected.
Barnes said that another important step in the study of animal airDNA will be to try to collect animal airDNA from outdoor animals rather than in research laboratories.
Originally published in “Life Science”.