Sensory ataxic neuropathy

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Histochemistry from muscle biopsy of a dog with sensory ataxic neuropathy, showing a bluish reaction for the affected dog (B), indicating lack of COX activity[1]

Sensory ataxic neuropathy is an autosomal-recessive genetic neurological disorder of Golden Retrievers[2].

The disease is caused by a missense base-pair deletion mutation in the mt tRNATyr gene that results in mitochondrial dysfunction, specifically reduced ATP production in isolated muscle mitochondria.

Affected dogs are usually young (under 6 months of age) and present with slowly progressive postural reaction deficits and reduced or absent spinal reflexes.

Clinical pathology, radiography, and electrophysiology of motor systems are frequently within reference values.

Electrophysiological examination usually reveals reduced conduction velocities of nerve impulses in sensory nerves.

Histopathology of muscle tissues are usually unremarkable although histochemical staining for cytochrome c oxidase and succinate dehydrogenase shows marked reduction in their activity in affected dogs.

A differential diagnosis would include ceroid lipofuscinosis and pyruvate dehydrogenase phosphatase 1 deficiency.

There is no known treatment for this condition and approximately 50% of affected dogs are euthanized before three years of age.

References

  1. Baranowska I et al (2009) Sensory ataxic neuropathy in golden retriever dogs is caused by a deletion in the mitochondrial tRNATyr gene. PLoS Genet 5(5):e1000499
  2. Jäderlund KH et al (2007) A neurologic syndrome in Golden Retrievers presenting as a sensory ataxic neuropathy. J Vet Intern Med 21:1307–1315