Narcolepsy (Dachshund Type)
Affected Genes: HCRTR2
Inheritance: Autosomal Recessive
Variant(canFam6):
chr12:22408409: G>A
Breed: Dachshund
Miniature Longhaired Dachshund
Miniature Smooth Dachshund
Miniature Wirehaired Dachshund
Standard Longhaired Dachshund
Standard Smooth Dachshund
Standard Wirehaired Dachshund
General Information: Narcolepsy (NA) (Dachshund Type) is a genetic sleep disorder affecting Dachshunds, marked by excessive daytime sleepiness and sudden, transient episodes of muscle weakness or paralysis often triggered by excitement such as play or food. Dogs with this inherited form of narcolepsy typically show symptoms between one to six months of age, including an inability to stay awake for extended periods and episodes of collapse and sleep following positive stimulation. During these episodes, affected dogs experience a sudden loss of muscle tone and appear uncontrollably sleepy, though they may not always completely fall asleep. Symptoms usually stabilize after the dog's first year and do not progress in severity, and affected dogs do not have other associated health problems.
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 for Narcolepsy (NA) (Dachshund Type) involves screening for mutations in the HCRTR2 gene to determine carrier status. This disorder is inherited in an autosomal recessive manner, meaning a dog must inherit two copies of the mutated gene, one from each parent, to develop the condition. Carriers of the gene mutation do not typically exhibit symptoms but can pass the mutation to their offspring. When two carriers are bred, each puppy has a 25% chance of being affected and a 50% chance of being a carrier. To prevent producing affected puppies and eliminate the mutation from breeding lines, it is crucial to avoid breeding two carriers. Dogs that are not carriers of the mutation do not pose a risk of producing affected puppies, making genetic testing an essential tool in responsible breeding practices.
References:
Chen L, Brown RE, McKenna JT, McCarley RW. Animal models of narcolepsy. CNS Neurol Disord Drug Targets. 2009 8(4):296-308.
Hungs M, Fan J, Lin L, Lin X, Maki RA, Mignot E. Identification and functional analysis of mutations in the hypocretin (orexin) genes of narcoleptic canines. Genome Res. 2001 11(4):531-539.