North Carolina State University-led study found it is possible to retrieve forensically relevant information from human DNA in household dust.
When perpetrators clean crime scenes, dust isn’t something they usually think of. The thought to use “dust” just might confirm individuals who have been in a space but left no trace blood, saliva or hair.
Kelly Meiklejohn, assistant professor of forensic science and coordinator of the forensic sciences cluster at NC State and her team found that after sampling indoor dust from 13 households, the researchers were able to detect DNA from household residents over 90% of the time, and DNA from non-occupants 50% of the time. The work could be a way to help investigators find leads in difficult cases.
Specifically, the researchers were able to obtain single nucleotide polymorphisms, or SNPs, from the dust samples. SNPs are sites within the genome that vary between individuals – corresponding to characteristics like eye color– that can give investigators a “snapshot” of the person.
“SNPs are just single sites in the genome that can provide forensically useful information on identity, ancestry and physical characteristics – it’s the same information used by places like Ancestry.com – that can be done with tests that are widely available,” says Kelly Meiklejohn, assistant professor of forensic science and coordinator of the forensic sciences cluster at NC State. Meiklejohn is corresponding author of the study.