Narcolepsy - Labrador Retriever

Narcolepsy is a disabling sleep disorder affecting different dog breeds. It is characterized by daytime sleepiness, cataplexy, and striking transitions from wakefulness into rapid eye movement (REM) sleep. Dogs with narcolepsy exhibit cataplexy, sudden episodes of muscle weakness akin to REM sleep–associated atonia that are triggered primarily by positive emotions. Animals in narcoleptic state are almost without muscular tonus. The first signs of disease may be apparent as early as 4 weeks to 6 month of age. The frequency of episodes is specific for each animal, however the frequency of episodes in general is declining with age. Disease is inherited as autosomal recessive trait where mutations in OX2R gene have been shown to segregate perfectly with diseased individuals.

Inheritance: autosomal recessive

Mutation: HCRTR2 gene

Genetic test: The method used for testing is extremely accurate and allows complete differentiation between affected animals, carriers and healthy dogs. Testing can be done at any age.