Criminals should take note of this research. The advice is that criminals should not live with a cat because DNA testing on cat hairs might lead to a cat owning criminal being convicted for a crime at a property or other place where they leave behind cat/dog hairs.
Scenario
I can think of one very distinct circumstance under which a criminal might be convicted because they own a cat. I’m talking about burglars. There are some really heavy duty, prevalent burglars in the UK. Let’s say they have a cat or two.
Their cats like to sleep on his lap. He decides to go out burgling one evening. He doesn’t change his clothes and he manages to get into some houses. As he rummages around the place looking for valuables, he deposits some of his cats’ hairs residing on his clothes onto furniture or the carpet.
A good forensic team could locate those hairs and identify them as feline and then through modern DNA testing link the criminal to the crime. It is akin to using fibres from clothes to link a criminal to a crime scene.
RELATED: First forensic science laboratory to focus solely on crimes against animals
Problem with DNA testing of cat hair
The problem until now has been that it has been impossible to do this because most cat hairs do not contain a root or it is dead resulting in almost no nuclear DNA sequence. Also, domestic cats have a very few number of ancient ancestors which means their DNA is very similar which in turn means that it is very difficult to differentiate one cat from another through nuclear DNA testing.
Research has now found a new method which uses every part of the mitochondrial DNA. This enables forensic scientists to detect tiny differences between cats which should help them to link a domestic cat to a criminal and therefore the crime.
In the UK you will find a domestic cat in 26% of households. And there must be some burglars/criminals who are cat owners. There must indeed be many criminals who own a cat although they are more likely to own a dog I would have thought. The authors say the technique will be as effective for dogs.
Although mitochondrial DNA is less variable than nuclear DNA, my research tells me that there is just a 3% chance that two cat share the same DNA of this type.
Marc Jopling, the professor of genetics at Leicester University and a co-author of the study said that, “In criminal cases where there is no DNA available to test, pet hair is a valuable source of linking evidence, and our method makes it much more powerful. The same approach could also be applied to other species, and particularly dogs.”
Dr. Jon Whetton, the other co-author, also of, Leicester University’s Department of Genetics and Genome Biology added that, “If the police have a case where there are cat hairs but no human DNA to link a suspect with a crime it is now likely that, using our approach, we would be able to exclude the great majority of cats as the source and demonstrate a stronger link to the suspect’s cat. The approach could be applied to other species, dogs being the most relevant as their hairs are also frequently found on clothing.”
Mitochondrial DNA
The study is published on the Forensic Science International Genetics website. The difference between mitochondrial DNA and nuclear DNA is that the former is inherited only from the mother while nuclear DNA is also inherited from the father. Nuclear DNA is larger in size and linear compared to mitochondrial DNA which is circular and smaller.
Nuclear DNA encodes for proteins that work for the entire cell while mitochondrial DNA replicates separately from the nuclear DNA. It also encodes for proteins that work only for the mitochondria. Nuclear DNA is found in the nucleus of the cell while mitochondrial DNA is found in the mitochondria. The source for this information is the artificial intelligence service provided by Bing, the search engine.
RELATED: 4 U.S. states where bestiality is not a crime
Tags:
