Sensory Neuropathy (SN)

 

Gene: FAM134B

Transmission: Autosomal recessive

For an autosomal recessive genetic disease an animal must have two copies of the mutation in question to be at risk of developing the disease. Both parents of an affected animal must be carriers of at least one copy of the mutation. Animals that have only one copy of the mutation are not at risk of developing the disease but are carrier animals that can pass the mutation on to future generations.

Mutation: Chromosomal inversion, FAM134B gene; 6.5 Mb inversion on chromosome 4

Medical system: Neurological

Breeds: Border Collie, German Shepherd, Rottweiler

Age of onset of symptoms: between 2 and 7 months of age

Sensory neuropathy of the Border Collie is an autosomal recessive genetic neurological disease characterized by degeneration of sensory and motor neurons.  Affected individuals show neurological signs including progressive incoordination (proprioceptive ataxia), hyperextension of limbs, intermittent knuckling of the paws (paws dragging along the ground when walking) and self-mutilation of distal limbs. The pelvic limbs are often more severely affected than the front limbs. Other symptoms may include decreased pain sensation (nociception) in all limbs, urinary incontinence and regurgitation. Carrier animals are normal.  Screening for the mutation by DNA testing of breeding animals will make it possible to reduce the frequency of this disease.

 

References:

OMIA link: [2032-9615]

Donner J, Freyer J, Davison S, et al. (2023) Genetic prevalence and clinical relevance of canine Mendelian disease variants in over one million dogs.  PLoS Genet. 19(2):e1010651. [pubmed/36848397]

Correard S, Plassais K. Lagoutte L, et al. (2019)  Canine neuropathies: powerful spontaneous models for human hereditary sensory neuropathies.  Hum Genet 138(5):455-466.  [pubmed/30955094]

Amengual-Batle P, Rusbridge C, José-López R, et al. (2018) Two mixed breed dogs with sensory neuropathy are homozygous for an inversion disrupting FAM134B previously identified in Border Collies. J Vet Intern Med. 32(6):2082-2087.[pubmed/30307654]

Forman OP, Hitti RJ, Pettitt L, et al. (2016) An Inversion Disrupting FAM134B Is Associated with Sensory Neuropathy in the Border Collie Dog Breed. G3 (Bethesda) 6(9):2687-92. [medline/27527794]

Wheeler SJ. (1987) Sensory neuropathy in a Border Collie Puppy.  Journal of small animal practice 28:281-289.

 

Contributed by: Emily Morgan, Class of 2020, Faculty of Veterinary Medicine, University of Montreal.