A database of cat DNA has been set up and has already helped convict a killer.
It was used to show 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.
DNA for 152 cats has been collected by University of Leicester scientists, who now hope to publish it so it can be used in future investigations.
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.
"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, eight cat hairs were found on the torso of Mr Guy, who was found on a Southsea beach wrapped in a curtain.
California scientists analysed the hairs and found the mitochondrial DNA matched the suspect's cat.
The DNA type was unique among 493 randomly sampled US cats.
Doctor Wetton, working with Hampshire Police, set out to discover if it was equally rare in the UK - and, more specifically, in the area of the crime.
He looked at 23 cats from Southsea and another 129 from the rest of the country and found only three matches, confirming that the DNA type was indeed rare.
That evidence helped the prosecution get a successful conviction for manslaughter at Winchester Crown Court in July.
The samples collected form the new cat DNA database, which scientists hope can be built up over time.
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."