Scientists and investigators might not need to scoop up DNA from surfaces in the future. According to Science Focus, researchers at the Queen Mary University of London have shown that you can collect "environmental DNA" (eDNA) from the air.
The team used a peristaltic pump combined with pressure filters to grab samples of naked mole rat DNA for five to 20 minutes, and then used standard kits to find and sequence genes in the resulting samples. This method not only pinpointed the mole rats' DNA (both in their housing and in the room at large), but caught some human DNA at the same time.
Lead author Dr. Elizabeth Claire said the work was originally meant to help conservationists and ecologists study biological environments. With enough development, though, it could be used for considerably more. Forensics units could pluck DNA from the air to determine if a suspect had been present at the scene of a crime. It might also be useful in medicine — virologists and epidemiologists could understand how airborne viruses (like the one behind COVID-19) spread.
Any practical uses are a long way off. The research unit is already working with private companies like NatureMetrics to develop practical applications. It's easy to see limitations — you want to use this in areas where you know what DNA to expect, so it might not work well in crowded rooms or in outdoor spaces. However, merely having this option could be very useful in situations where surfaces don't provide clear answers.