Polyneuropathy (Leonberger and Saint Bernard Type)
Affected Genes: ARHGEF10
Inheritance: Autosomal Recessive
Variant(canFam6):
chr16:49746536-49746546: 10 bp deletion CACGGTGAGC
Breed: Leonberger
Saint Bernard
St. Bernard
General Information: Polyneuropathy (PN) (Leonberger and Saint Bernard Type) is an inherited neurologic disorder that typically presents in dogs before they reach 3 years of age. Affected dogs show signs of generalized neurologic disease, including weakness, loss of muscle tone, muscle atrophy, an awkward high-stepping gait in the hind limbs, decreased reflexes, abnormal bark sounds, and increased breathing sounds due to laryngeal paralysis. As the disease progresses, affected dogs may become unable to bear weight or walk. While this condition is generally considered autosomal recessive, meaning two copies of the mutation are needed to develop the disease, some carriers (dogs with only one copy of the mutation) might also be at risk.
How to Read Your Dog's Test Results for this Genetic Variant:
Two Variants Detected: Dog Likely Affected
One Variant Detected: Dog Unlikely Affected
No Variants Detected: No Effect
Gene / Testing Information: Genetic testing of the ARHGEF10 gene can determine if a dog is a carrier of Polyneuropathy (PN) (Leonberger and Saint Bernard Type). This disease is primarily inherited in an autosomal recessive manner, requiring two copies of the mutated gene for a dog to be affected. However, there is a possibility that carriers, who have only one copy of the mutation, could also be susceptible to the disease. When two carriers are bred, there is a 25% chance of each pup inheriting the disease and a 50% chance of each being a carrier. Reliable genetic testing is crucial for making informed breeding decisions, especially since symptoms might not appear until adulthood. To prevent producing affected pups and to eliminate this mutation from breeding lines, it is recommended not to breed two known carriers together. Dogs that are not carriers of the mutation do not have an increased risk of having affected pups.
References:
Ekenstedt KJ, Becker D, Minor KM, Shelton GD, Patterson EE, Bley T, Oevermann A, Bilzer T, Leeb T, Drögemüller C, Mickelson JR. An ARHGEF10 deletion in highly associated with a juvenile-onset inherited polyneuropathy in Leonberger and Saint Bernard dogs. PLoS Genet. 2014 10(10):e1004635.