Neuroaxonal Dystrophy, NAD (Spanish Water Dog type)

Gene: TECPR2

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: Substitution, TECPR2 gene; c.4009 C>T, p.(R1337W)

Medical system: Neurological

Breeds: Lagotto Romagnolo, Spanish Water Dog

Note that Neuroaxonal Dystrophies (NADs) of differing severities and age of onset are seen in different breeds and are caused by mutations in different genes.  Here is a summary:

NAD, Giant Schnauzer type.  A severe disease that is lethal at birth.  MFN2 gene, OMIA [2153].

NAD, Papillon type: A progressive neurological disease with onset of symptoms by 3-4 months and death by 7-8 months.  PLA2G6 gene, OMIA [2105]

NAD, Rottweiler type.  A slowly progressive degenerative disease with a young adult onset usually resulting in ethical euthanasia.  VPS11 gene, OMIA [2152].

NAD, Spanish Water Dog type. A progressive degenerative disease with an onset of 6-11 months and ethical euthanasia by 2 years. TECPR2 gene, OMIA [1975]

References:

OMIA link: [1975-9615]

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]

Stee K, Van Poucke M, Lowrie M, et al. (2023) Phenotypic and genetic aspects of hereditary ataxia in dogs. J Vet Intern Med. [pubmed/37341581]

Hahn K, Rohdin C, Jagannathan V, et al. (2015) TECPR2 associated neuroaxonal dystrophy in Spanish Water Dogs.  PLOS one 10(11):e141824 [pubmed/26555167]