Globoid Cell Leukodystrophy

Globoid cell leukodystrophy (GCL, or Krabbe's disease in humans) is a degenerative disease of the brain and spinal cord associated with gradual and symmetrical destruction of the white matter of the brain. It is called globoid cell leukodystrophy because of the characteristic storage cells found around cerebral blood vessels in the white matter of affected animals. The disease results from a genetic deficiency of the enzyme galactocerebrosidase (GALC) involved in the breakdown of certain fats in the brain and spinal cord.

Signs of Globoid Cell Leukodystrophy

Signs begin early in life and progress rapidly and include weakness, stumbling, loss of control of the hindquarters, and tail tremors. Then the dog will develop a wide stance, lack of coordination, and hind or total limb paralysis. He may become blind or fail to recognize familiar individuals. GCL may occur as early as 4 weeks of age and nearly always occurs before 5 to 6 months of age. The typical clinical signs and measurement of the main activity of galactocerebrosidase (GALC) in white blood cells will confirm a positive diagnosis.

Globoid cell leukodystrophy seems to affect a small number of related Irish setters and Dalmatians. Other dog breeds reported with GCL include Pomeranian, Miniature Poodle, Basset Hound, Beagle, West Highland White Terrier, Cairn Terrier, Coonhounds. The disease has been seen in domestic shorthaired kittens in which it causes progressive degeneration of the nervous system and death between 2 and 6 months of age.

Treatment of Globoid Cell Leukodystrophy

No treatment exists; GCL is fatal. Most common in Westies and Cairns, the disease is known to be an autosomal recessive disease (two parents are required).

Fortunately, an accurate blood test (using DNA technology) is now available to concerned breeders. It can accurately identify a dog as a carrier, as affected, or as clear of the disease. Testing a small blood sample identifies "carriers," whose offspring have a 50% chance of carrying the gene, but who will themselves be clear. Breeders should test any dog in their breeding program to determine whether or not he's a carrier. This important tool is an opportunity to minimize the number of carriers in the Westie population and eventually eliminate GCL altogether. Any bloodline contaminated with the defective gene will produce affected puppies when linebreeding on the source of the defect.

References:
1. The West Highland White Terrier. Jill Arnel
2. The Official Book of the Dalmatian
3. The Cat Care Book: All You Need to Know to Keep Your Cat Healthy and Happy. Sheldon L. Gerstenfeld
4. A Practical Guide to Canine and Feline Neurology. Curtis W. Dewey