To move quickly, some rabbits throw up their back legs and walk on their front paws
One defective gene might turn some bunnies’ hops into handstands, a new study suggests.
To move quickly, a breed of domesticated rabbit called sauteur d’Alfort sends its back legs sky high and walks on its front paws.
Sauteur d’Alfort rabbits aren’t the only animal to adopt an odd scamper if there’s a mutation to this gene, known as RORB. Mice with a mutation to the gene also do handstands if they start to run, says Stephanie Koch, a neuroscientist at University College London who was not involved with the rabbit work.
Understanding why the rabbits move in such a strange way could help researchers learn more about how the spinal cord works. The study is “contributing to our basic knowledge about a very important function in humans and all animals — how we are able to move,” says Leif Andersson, a molecular geneticist at Uppsala University in Sweden.
In the rabbit study, Andersson and colleagues bred hop-less sauteur d’Alfort male rabbits with New Zealand white female rabbits that can hop. The team then scanned the genetic blueprints of the offspring that couldn’t hop and looked for mutations that didn’t appear in offspring that could.
A mutation in the RORB gene popped up as a likely candidate for the rabbits’ acrobatic handstands. That change creates faulty versions of the genetic instructions that cells use to make proteins, the researchers found. As a result, there appears to be less of the RORB protein in specialized nerve cells in rabbits that have the mutation compared with rabbits that don’t.
Those spinal cord nerve cells, called interneurons, help coordinate the left and right side of the body and are crucial for a normal gait, Andersson says. Without the RORB protein in interneurons, the rabbits may lack the ability to coordinate what their hind limbs are doing, which restricts their ability to hop.
