Neonatal Ataxia (BNAt)
Neonatal ataxia is an autosomal recessive disease of Coton de Tulear dogs. The ataxia of affected dogs becomes apparent as soon as their littermates develop coordinated movements. The affected puppies exhibit titubation of the head and intention tremors and most are unable to walk. They have delayed righting reflexes and severely decreased or absent proprioceptive positioning and show fine vertical ocular tremors at rest. There is no progression or remission of clinical signs. Ultrastructural abnormalities can be observed in the molecular layer of the cerebellum.
Neonatal Ataxia is inherited as a recessive trait. That means that for a pup to be affected, they must have two copies of the defective gene. For this to happen, both the parents must be carriers. They each have one copy of the defective gene that they passed on to the unlucky pup. They do not show signs of the disease because they also have one copy of the normal gene which is enough for their brains to function normally. About 10% of Coton de Tulear are carriers of the genetic mutation responsible for the disease.
Zeng, R., Farias, F.H.G., Johnson, G.S., McKay, S.D., Schnabel, R.D., Decker, J.E., Taylor, J.F., Mann, C.S., Katz, M.L., Johnson, G.C., et al. (2011). A truncated retrotransposon disrupts the GRM1 coding sequence in Coton de Tulear dogs with Bandera’s neonatal ataxia. J. Vet. Intern. Med. 25, 267–272.