The UK’s first cat DNA database has been created and has already been used in court to help convict a killer.
University of Leicester forensic scientists compiled data from 152 cats around the country which they now hope to publish so it can be used in future crime investigations.
The database was used to demonstrate the likelihood that cat hairs found on the dismembered torso of Hampshire man David Guy belonged to Tinker, a cat owned by main suspect David Hilder.
The evidence was used as part of the prosecution case, leading to the successful conviction of Hilder for manslaughter. Dr Jon Wetton, who led the project, said: "This is the first time cat DNA has been used in a criminal trial in the UK. We now hope to publish the database so it can be used in future crime investigations. "This could be a real boon for forensic science, as the 10 million cats in the UK are unwittingly tagging the clothes and furnishings in more than a quarter of households."
In July last year, the torso of Mr Guy was found on a Southsea beach wrapped in a curtain, on which eight cat hairs were found.
Hampshire Constabulary sent the hairs to California for analysis, where the scientists examined the cat's mitochondrial DNA, which is a type of DNA contained in small structures within cells and passed down the maternal line.
The mitochondrial results showed not only a match with the suspect’s cat Tinker, but also that the same DNA type had not been seen among 493 randomly sampled US cats.
The police were keen to know if the type was equally rare in the UK — and, more specifically, in the area of the crime. Hampshire police tracked down Dr Wetton — who had created a similar database of UK dogs while working with the Forensic Science Service (FSS).
He proposed that he would have to create a UK cat database from scratch to analyse the findings, and set to work with PhD student Barbara Ottolini. The team were able to get the samples from a company which handles analysis of blood from pets for vets across the country.
The samples showed cats’ ages, gender and postcode — with 23 cats from Southsea and another 129 from a range of places throughout the rest of the country. Only three of the samples obtained matched the hairs from the crime scene, confirming that it was indeed an uncommon type in the UK. This evidence was presented at Winchester Crown Court, and formed part of the prosecution case successfully convicting Hilder for manslaughter.
Dr Wetton said: “Within each cat hair are two types of DNA, individual-specific ‘nuclear DNA’ detectable in the roots of some larger hairs, and ‘mitochondrial DNA’ which is shared by all maternally-related individuals and can be found even in the finest hair shafts. “Animal DNA offers a way of linking people to places and items through the transfer of their pet’s hairs.”