Goodbye K9? Scientists Create Mutant Mice That Can Detect Explosives, Drugs And Diseases

Scientists from the United States have mutated mice that could possibly be employed as "super sniffers" in the future.

According to Science Mag, a mouse has about 1,200 genes dedicated to odorant receptors, which are cellular sensors that respond to a certain scent, making them naturally good sniffers.

A mouse's nose, same with any mammalian nose, is packed with tiny receptors, specialized to pick up different scents. But each hosts only a single odorant receptor.

Researchers at Hunter College, part of the City University of New York, wanted to understand how these neurons work and choose a specific receptor, so they tinkered the mouse genome.

First, they introduced the DNA for an odor receptor gene transgenically by injection into the nucleus of a fertilized egg cell. Next, they added an extra string of DNA to the gene sequence to see if the probability of the gene being chosen would be altered.

Resuts showed that the extra receptors were working. More DNA copies led to the mouse's "super sniffer" ability.

Using scents of a chemical that has a sweet smell similar to jasmine and another that smells like peppermint, results show that mutated mice could detect lower doses of these odors than non-mutated mice.

"The animals could smell the odor better because of the increased presence of the receptor," said Charlotte D'Hulst, one of the team's researchers, in a statement.

The scientists also tried to insert a human receptor gene into the mouse using the transgenic super-sniffer technique and it also worked.

"We have developed a system where we can study human odor receptors and finally determine how human odor coding works," said lead investigator Paul Feinstein.

These mice, whose genomes have been engineered, are envisioned to detect land mines or chemical signatures of diseases, like Parkinson's and Alzheimer's in humans.

In an interview with BBC, D'Hulst also said they are aiming to apply this research to detecting drugs or explosives.

"We want to create an explosive-detecting rat or mouse--and we could also do this for narcotics such as cocaine, for example," said D'Hulst.

"If we can find the receptor that is activated by cocaine, we could create 'super-sniffing' cocaine rodents," she added.

The study was published in the journal Cell Reports.