A single cat hair contains DNA which could link a suspect and a crime-scene, or a victim, according to a new study led by University of Leicester scientist Emily Patterson.
Domestic cats are among the most common household pets.
In the United Kingdom, for example, there are an estimated total of about 11 million, residing in 26 % of homes.
Within such environments, cat hairs are continuously shed and transfer readily to the belongings and clothing of associated humans.
The recovery of cat hairs from a crime scene may therefore provide important evidence, linking a suspect and a victim, for instance.
As shed hairs normally originate from the cat’s undercoat, they provide minimal diagnostic characteristics and are of limited value in microscopic comparison.
Comparative visual analysis is further complicated by extensive variation of hairs even within a single animal.
In their new paper, Patterson and colleagues describe a novel method that can extract maximum DNA information from just one cat hair.
“Hair shed by your cat lacks the hair root, so it contains very little usable DNA,” Patterson said.
“In practice we can only analyze mitochondrial DNA, which is passed from mothers to their offspring, and is shared among maternally related cats.”
“This means that hair DNA cannot individually identify a cat, making it essential to maximise information in a forensic test.”
However, our new method enabled us to determine the sequence of the entire mitochondrial DNA, ensuring it is around 10 times more discriminating than a previously used technique which looked at only a short fragment.
“In a previous murder case we applied the earlier technique but were fortunate that the suspect’s cat had an uncommon mitochondrial variant, as most cat lineages couldn’t be distinguished from each other,” said University of Leicester’s Dr. Jon Wetton.
“But with our new approach virtually every cat has a rare DNA type and so the test will almost certainly be…
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