Tag Archives: American Kennel Club Canine Health Foundation

Gene discoveries in canine ataxia

What do the Gordon Setter and Old English Sheepdog have in common?

Both breeds suffer from a type of hereditary ataxia where neurons in the cerebellum that control movement begin to die, causing a gradual loss of coordination.   In humans, ataxia is also the 3rd most common neurodegenerative movement disorder (after Parkinson’s and Huntington’s diseases).

Old English Sheepdog

Researchers at the National Institute on Aging and the Broad Institute of MIT and Harvard looked at 630 Old English sheepdogs and mapped ataxia genetically in the families of affected animals. Eventually they mapped the disease to a gene, RAB 24, located on chromosome 4. A mutation in RAB 24 was closely associated with development of the disease, and on screening of affected dogs of other breeds, the identical mutation was found in Gordon setters, providing additional evidence that this mutation is important.

Gordon Setter

“Rab 24 is a protein that is believed to be important to the process of autophagy – which is how cells cleanse themselves of waste,” says North Carolina State neurologist Natasha Olby who collaborated on the research.

“We know that autophagy and neurodegeneration are connected, so pinpointing this protein is important to our understanding of the disease process.”

“We have not yet proven that this mutation causes neurodegeneration; it could simply be a very good marker for the disease,” Olby says. “Our next step will be to determine exactly how the mutation affects the protein Rab 24 and its function and to determine whether this results in neuron death. This gene will also be investigated in humans with hereditary ataxia.”

The findings appear in the journal PLOS Genetics. The research was funded by the American Kennel Club Canine Health Foundation with additional support from the Old English Sheepdog Club of America.

Source:  North Carolina State University media release

New gene therapy for dogs with hemophilia

Researchers at the UNC School of Medicine and the Medical College of Wisconsin have found that a new kind of gene therapy led to a dramatic decline in bleeding events in dogs with naturally occurring hemophilia A.

Photo courtesy American Kennel Club Canine Health Foundation, Inc

Photo courtesy American Kennel Club Canine Health Foundation, Inc

Hemophilia A affects about 50,000 people in the United States and millions more around the world.

Before the gene treatment, the animals experienced about five serious bleeding events a year. After receiving the novel gene therapy, though, they experienced substantially fewer bleeding events over three years.

Hemophiliacs lack  the coagulation factor VIII in their blood plasma.   In about 35% of cases, patients develop an antibody response to factor VIII, meaning that treatment by injection of the factor no longer works.

Using a plasmapheresis machine and a blood-enrichment technique, the research team isolated specific platelet precursor cells from three dogs that had hemophilia A. The team then engineered those platelet precursor cells to incorporate a gene therapy vector that expresses factor VIII. The researchers put those engineered platelet precursors back into the dogs. As the cells proliferated and produced new platelets, more and more were found to express factor VIII.

In the 2 1/2 years since the dogs received the gene therapy, researchers found that factor VIII was still being expressed in platelets that were coursing throughout the vascular systems of all three dogs. All three experienced much less bleeding. In the dog that expressed the most factor VIII in platelets, the bleeding was limited to just one serious event each year over the course of three years. And such bleeding events were easily treatable with current standard therapies.

The researchers have published their results in the journal Nature Communications.  You can read the article here.

While the goal of this research is to help human hemophiliac patients, I hope that the treatment is able to be offered more widely to dogs with the condition too!

Source:  UNC School of Medicine media statement