Scientists accidentally create super-vicious HAMSTERS in lab after gene editing test goes wrong

Scientists accidentally create super-vicious HAMSTERS in a lab after gene editing experiment goes wrong and makes aggressive rodents chase, bite and pin each other down

  • Gene editing lab test inadvertently makes horde of rage-fuelled hamsters
  • Scientists removed key hormone in the hope it would boost animals’ cooperation
  • But it turned them wild, prompting chasing, biting and pinning among hamsters
  • ‘We [thought] it would reduce aggression. But the opposite happened’: test chief
  • ‘We don’t understand this system as well as we thought we did’, Professor added

Scientists inadvertently bred a horde of unusually aggressive hamsters after a gene editing experiment to ‘reduce aggression’ went wrong.

Researchers at Georgia State University produced new rodents without hormone vasopressin in an effort to raise ‘social communication’ between the rodents.

Yet the chemical change turned the Syrian hamsters wild, prompting fights inside cages.

The ultra-vicious hamsters were pictured pinning, biting and chasing each other.

The scientists shared images of the genetically modified hamsters going at it in their cages

Hamsters are typically social animals with low levels of aggression and an ease of cooperation

Hamsters are typically social animals with low levels of aggression and an ease of cooperation

Lead researcher Professor Elliott Albers said: ‘We anticipated […] we would reduce both aggression and social communication — but the opposite happened.’

They key hormone Avpr1a was thought to regulate friendship and bonding, with its removal expected to increase harmony between the animals.

Instead, the lab experiment recorded ‘high levels of aggression towards other same-sex individuals’.

Professor Albers said: ‘We were really surprised at the results.’

It was thought that vasopressin affects the social behaviors of hamsters including aggression and communication.

CRISPR is a gene editing technique in which scientists can ‘snip’ a section of someone’s DNA

To further investigate, scientists deactivated Avpr1a, removing a receptor that interacts with vasopressin in key regions of the brain.

Now immune to the hormone, it was thought the rodents would become friendlier.

The results were anything but, with a heightened frequency of fighting, biting, chasing and pinning down among the hamsters in their cages.

The study’s striking conclusions challenge scientists’ understanding of the relationship between biology and behavior.

The professor added: We don’t understand this system as well as we thought we did.

‘The counterintuitive findings tell us we need to start thinking about the actions of these receptors across entire circuits of the brain, not just in specific brain regions.

‘Developing gene-edited hamsters was not easy. But it is important to understand that the neurocircuitry involved in human social behavior and our model has […] relevance for human health.’

Professor Albers said the gene editing tests are intended to help find solutions to neuropsychiatric disorders including autism and depression.


The CRISPR gene editing technique is being used an increasing amount in health research because it can change the building blocks of the body.

At a basic level, CRISPR works as a DNA cutting-and-pasting operation.

Technically called CRISPR-Cas9, the process involves sending new strands of DNA and enzymes into organisms to edit their genes.

In humans, genes act as blueprints for many processes and characteristics in the body – they dictate everything from the color of your eyes and hair to whether or not you have cancer.

The components of CRISPR-Cas9 – the DNA sequence and the enzymes needed to implant it – are often sent into the body on the back of a harmless virus so scientists can control where they go.

Cas9 enzymes can then cut strands of DNA, effectively turning off a gene, or remove sections of DNA to be replaced with the CRISPRs, which are new sections sent in to change the gene and have an effect they have been pre-programmed to produce.

But the process is controversial because it could be used to change babies in the womb – initially to treat diseases – but could lead to a rise in ‘designer babies’ as doctors offer ways to change embryos’ DNA.

Source: Broad Institute



Leave a Comment