Pets at a crime scene may help to gather key evidence but rarely are they considered for their role in human DNA transfer.
For the first time, Flinders University forensic science researchers have examined the presence and transfer of human DNA on pets such as cats and dogs.
This research considers cats both as receptors and vectors for DNA of a person of interest – providing key evidence in criminal investigations.
In collaboration with the Victoria Police Forensic Services Department, forensic science researchers Heidi Monkman and Dr Mariya Goray, both from the College of Science and Engineering at Flinders, collected human DNA from 20 pet cats from multiple households.
Detectable levels of DNA were found in 80% of the samples – and interpretable profiles that could be linked to a person of interest were generated from 70% of the cats tested.
“Now that we know that human DNA is readily detectable on companion animals such as cats, it is important to fill in the gaps in the knowledge available to date,” says PhD candidate Ms Monkman.
“Collection of human DNA from animals may become an important tool in crime scene investigations, however there is a lack of data on companion animals such as cats and dogs in their relationship to human DNA transfer to draw any strong conclusions yet.”
An experienced crime scene investigator and expert in DNA transfer, Dr Goray says this data can be very relevant when interpreting forensic DNA results obtained from a crime scene that includes pets.
“This type of data can help us understand the meaning of the DNA results obtained, especially if there is a match to a person of interest,” she says.
“Are these DNA findings a result of a criminal activity or could they have been transferred and deposited at the scene via a pet?”
The researchers say that further research is required on the transfer, persistence and prevalence of human DNA to and from cats and other pet animals, along with the influences of animal behavioural habits, the DNA shedder status of the owners and many other relevant factors.
To this end, further collaborative work on cats and dogs is currently underway at the Flinders University forensic laboratory.
The article, Is There Human DNA on Cats (2022) by Heidi Monkman, Roland AH van Oorschot (La Trobe University and Victoria Police Forensic Services) and Mariya Goray, has been published in Forensic Science International: Genetic Supplement Series (Elsevier) DOI: 10.1016/j.fsigss.2022.10.014