Mice (and even humans) might really have the ability to become venomous, snake venom scientists say unconventional news
Mice and even humans could have the potential to become toxic, according to new research.
Scientists have found that the genetic basis for the development of oral venom lies in reptiles and mammals.
The study shows the first evidence of an association between the venom glands in snakes and the salivary glands in mammals.
Study author Agneesh Barua joked, “It definitely gives a whole new meaning to a poisonous person.”
In the study, scientists from the Graduate University of the Okinawa Institute of Science and Technology and the Australian National University looked for genes that work alongside and interact with the venom genes.
They used venomous glands from the Taiwanese habu snake – a pit viper found in Asia – and identified around 3,000 of these “cooperating” genes. They found that they played an important role in protecting cells from stress caused by the production of many proteins.
The genomes of other creatures, including dogs, chimpanzees, and humans, were also examined, and researchers found that they had their own version of such genes.
The salivary gland tissues had a pattern of activity similar to that of the snake venom glands – suggesting that the salivary glands in mammals and the venom glands in snakes share an ancient functional core.
Mr Barua said, “Many scientists have intuitively believed this to be true, but this is the first really solid evidence to support the theory that venom glands evolved from early salivary glands.
“Then while snakes went insane, adding many different toxins to their venom and increasing the number of genes involved in producing venom, mammals like shrews produce a simpler venom that is very similar to saliva.”
Experiments in the 1980s showed that male mice “produce compounds in their saliva that are highly toxic when injected into rats,” he said.
“If mice that produce more poisonous proteins in their saliva achieve better reproductive success under certain ecological conditions, we can come across poisonous mice in a few thousand years.”
If the right ecological conditions ever existed, humans could also become toxic, though those conditions are unlikely, he added.
The research is published in the PNAS journal.