Cyclic Neutropenia is
a recessive stem cell disorder that affects both smooth and rough
collies. Also known as Cyclic
Hematopoesis or "Gray Collie Syndrome," dogs affected
by cyclic neutropenia appear visibly lighter than non-affected littermates,
even from puppies with the merle coloration. Because this disorder
is recessive, a dog can be a carrier without exhibiting any outward
symptoms, and can still pass on a copy of the mutation to any offspring.
Cyclic Neutropenia is a disease that affects
the neutrophils of a dog, which are an integral part of the dog's
immune system. Every 10-12 days, the dog will experience a dramatic
drop in the number of neutrophils circulating through his blood
stream, leaving him extremely susceptible to infections. The dog
will often experience diarrhea, fever, joint pain, or other symptoms
associated with eye, respiratory, or skin infections. Bleeding episodes
can also occur. Unfortunately, most affected dogs will die as puppies,
and even with the best care, the dog will not likely live past 2-3
years of age.
Gray Collie Syndrome is an autosomal recessive mutation, meaning
that a dog must have two copies of the mutation in order to display
the signs and symptoms associated with this disorder. This also
means that a parent can be a carrier of this disorder, but not show
any signs. A dog that carries the mutation can either pass on the
normal or mutant allele to any offspring. Therefore, if two parents
that are carriers then produce a litter of pups, there is a 25%
chance of that each parent will pass on the mutation, and having
a pup that is affected by Gray Collie Syndrome.
Animal Genetics is currently testing for the
mutation responsible for Gray Collie Syndrome, also known as Canine
Cyclic Neutropenia or Canine Cyclic Hematopoiesis.
Collect sample using buccal swabs provided by
Animal Genetics. Ensure that the dog has not eaten within a few
hours of sample collection. Any food particles can inhibit the test.
Rub each of the swabs along the inside of the dog's mouth for 10-15
seconds, and allow the swabs to dry thoroughly. Label the provided
envelope with the dog's name, and place the swab inside it. Download
and complete a submission form for each sample and send along with
payment to Animal Genetics for testing.
Results are given using the following symbolic
The dog carries two copies of the mutant gene and is homozygous
for Canine Cyclic Neutropenia. The dog will appear gray in color,
and will experience symptoms associate with the disorder. The
dog will always pass on a copy of the mutation to any offspring.
Both the normal and mutant copies of the gene detected. The
dog is a carrier for Gray Collie Syndrome, and could pass on
either allele to any offspring.
Tested negative for the Canine Cyclic Neutropenia mutation.