Are you tired of your cat scattering its fur all over your couch? 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 could still help identify the perpetrators of an offence. 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 have demonstrated , both researchers in forensic science at Flinders University in Australia, and the team of forensic scientist Roland van Oorschot, from the Victorian Police Department of Scientific Services.
To reach this conclusion, the research team took hair swabs from twenty felines from fifteen different homes, along with the owners’ DNA. Each sample was then analyzed and the households completed a questionnaire on the daily life of their cat. This included knowing how often the animal was petted, and by whom, within the home.
In 80% of the samples, a significant amount of DNA was found, and 70% could be suitably interpreted for scientists to generate profiles. Most of these molecules came from residents of the household, but in six animals, the DNA of strangers was detected, although 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 quantity of molecules present and the time elapsed 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 great step towards collecting more comprehensive forensic evidence in the future. Even if certain variables – such as the duration of the presence of the molecule in the coat of cats – remain unknown, this research should be very useful for police investigations.
DNA analysis technologies have become so sophisticated in recent years that the tiniest traces of genetic material may be relevant to an investigation. If this is not enough to identify a suspect, the molecule can on the other hand 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 on the transfer of human DNA to and from felines is paramount. It is just as essential to know the persistence of this molecule on cats so that this tool is a reliable and real help during police investigations.she finishes. What if your cat is currently carrying the DNA of a murderer? You would never look at it the same way again.