Autosomal Recessive Neuronal Degeneration
Affected Genes: SACS
Inheritance: Autosomal Recessive
Variant(canFam6):
chr25 :15378293-15378296 4 bp deletion TTAG
Breed: Great Pyerenees
General Information: Autosomal Recessive Neuronal Degeneration (ARND) is an inherited disorder in dogs characterized by the progressive degeneration of neurons, primarily in the brain and spinal cord. This condition results from a genetic mutation in a specific gene responsible for normal neuronal function. Dogs with two copies of the associated mutation are predisposed to ARND, which typically manifests in early life. Symptoms include uncoordinated movements (ataxia), muscle weakness, tremors, seizures, vision loss, and behavioral changes. As the disease progresses, it can lead to severe neurological impairment and significantly impact the quality of life. While dogs with one copy of the mutation (carriers) usually do not show symptoms, they can pass the gene to their offspring, perpetuating the condition within the breed. Early detection through genetic testing and careful breeding practices are essential for managing and potentially eliminating ARND.
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 specific gene associated with Autosomal Recessive Neuronal Degeneration can determine if a dog is a carrier of this condition. ARND is inherited in an Autosomal Recessive manner, meaning that dogs must inherit two copies of the mutated gene, one from each parent, to develop the disease. Carrier dogs, possessing only one copy of the mutation, typically do not show symptoms but can pass the gene to their offspring. When two carriers are bred, each pup has a 25% chance of developing the disease and a 50% chance of being a carrier. Reliable genetic testing is crucial for informed breeding practices to eliminate this mutation from breeding lines, and breeding two carriers together is not recommended to avoid producing affected pups. Dogs that are not carriers have no increased risk of having affected offspring.
References:
Ekenstedt KJ, Minor KM, Shelton GD, Hammond JJ, Miller AD, Taylor SM, Huang Y, Mickelson JR. A SACS deletion variant in Great Pyrenees dogs causes autosomal recessive neuronal degeneration. Hum Genet. 2023 142(11):1587–1601.