A rare breed of acrobatic rabbits is making a quantum leap in scientists’ knowledge of mammalian movement.
An unusual rabbit walking on its front legs has revealed the genetic secrets behind other rabbits’ ability to jump.
The Alfort sweater is a rare breed of rabbit that walks on its front legs, with its hind legs in the air. To find out why these bunnies cannot jump, Miguel Carneiro from the University of Porto in Portugal, Leif Andersson from the University of Uppsala in Sweden and their colleagues conducted a Alfort sweater with a standard rabbit that can jump, and sequenced the genomes of the pair’s 52 grandchildren.
Baby rabbits that couldn’t jump, the researchers found, had a single mutation in both copies of a gene called RORBThese animals also had fewer neurons that expressed the protein RORB in their spinal cords, which likely disrupted the movement of their hind legs.
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.