A rare breed of acrobatic bunny enables a giant leap in scientists’ knowledge of movement in mammals.
An unusual rabbit that walks on its front legs has revealed the genetic secrets behind other rabbits’ ability to hop.
The sauteur d’Alfort is a rare breed of rabbit that walks on its front paws, with its hind legs in the air. To find out why these bunnies can’t hop, Miguel Carneiro at the University of Porto in Portugal, Leif Andersson at Uppsala University in Sweden and their colleagues bred a sauteur d’Alfort with a standard rabbit that can jump, and sequenced the genomes of the pair’s 52 grandchildren.
Baby rabbits that couldn’t hop, the researchers found, had a single mutation in both copies of a gene called RORB. These animals also had fewer neurons expressing the protein RORB in their spinal cords, which probably interfered with the movement of their hind limbs.
Previous studies had shown that mice with RORB mutations waddle like ducks, suggesting to the researchers that RORB is essential for normal spinal-cord development and movement in four-legged animals.