Are you tired of your cat spreading its fur all over your sofa? Perhaps you will change your mind after the recent study published in Forensic Science International: Genetics Supplement Series and highlighted by ScienceAlert. This new research suggests that our feline friends could provide compelling evidence in a criminal case. If they cannot give their testimony, they can still help identify the perpetrators of a crime. And it’s all thanks to their coats.
A cat’s fur can retain enough DNA from a person who has been in its vicinity to attest that a brief encounter between the two took place: this is what Heidi Monkman and Mariya Goray, both forensic researchers at Flinders University, have demonstrated in Australia, and the team of forensic pathologist Roland van Oorschot, from the Victorian Police Department of Scientific Services.
To reach this conclusion, the research team took hair sticks from twenty cats from fifteen different homes along with the owners’ DNA. Each sample was then analyzed and the households completed a questionnaire about their cat’s daily life. This included knowing how often the animal was petted, and by whom, in the home.
In 80% of the samples, a significant amount of DNA was found, and 70% could be interpreted appropriately for the researchers to generate profiles. Most of these molecules came from residents of the household, but in six animals DNA from strangers was detected, even though none of these households had had visitors for at least two days before the samples were taken. However, no correlation has yet been established between the amount of molecules present and the time that has passed since the last human contact, or with the length of the cat’s hair.
real little detectives
This new study, the first to examine how pets contribute to DNA transfer, is a big step toward collecting more extensive forensic evidence in the future. Although certain variables – such as the duration of the presence of the molecule in the cat’s fur – remain unknown, this research should be very useful for police investigations.
DNA analysis technologies have become so sophisticated in recent years that the smallest traces of genetic material can be relevant to an investigation. If this is not enough to identify a suspect, on the other hand, the molecule can be used to support other elements or establish innocence.
This is where pets come in: DNA taken from a surface does not necessarily require the individual to have been in direct contact with that area. The molecule may, for example, have been transported into the cells of the skin or into the hairs of a moving body. “Cats can be invaluable in assessing the presence and activities of household residents and recent visitors to a crime scene”assures Heidi Monkman.
“Further research into the transfer of human DNA to and from felines is essential. It is equally important to know the persistence of this molecule in cats, so that this tool is a reliable and real aid during police investigations.she concludes. What if your cat currently carries the DNA of a murderer? You would never look at it the same way again.