Genetic testing for Gray Collie Syndrome (Canine Cyclic Neutropenia) in Collies    
 

	The disease
	Canine Cyclic Neutropenia is a stem cell disorder that occurs in gray collies. Puppies are usually smaller and weaker than their littermates and by 8 to 12 weeks of age they develop clinical signs such as fever, diarrhea, joint pain, or other signs associated with eye, respiratory, or skin infections.   The disorder is caused by an abnormality of the stem cells in the bone marrow, from which all blood cells are developed. The result is a cyclic fluctuatian in blood cell numbers. Every 10 to 12 days the number of neutrophils drops dramatically, and then rebounds. There is an increased susceptibility to infection corresponding to the dip in neutrophil numbers. Affected dogs are subject to severe recurring bacterial infections, primarily of the respiratory or gastrointestinal tract.   These dogs are also prone to bleeding episodes due to the drop in blood cells numbers. This is a serious genetic disorder. Even with the best of care, affected dogs rarely live beyond 2 or 3 years of age. The disease occurs in all gray (not merle) collies. Affected puppies have a silver gray hair coat, sometimes with a slight yellowing due to a mixture of light beige and light gray hair.

	The mutation and inheritance
	GCS is inherited as an autosomal recessive trait. Both parents must carry the abnormal gene for the offspring to be affected. So there are three conditions a dog can be: it can be clear (genotype N/N or homozygous normal) meaning that it does not carry the mutation and will not develop the GCS. Since it also cannot pass the mutation onto its offspring, it can be mated to any other dog.   A dog which has one copy of the mutated gene and one copy without the mutation is called a carrier or heterozygous (genotype N/GCS); while it will not be affected by GCS, it can pass the mutation onto its offspring and should therefore only be mated to clear dogs.   Dogs that develop GCS have two mutated gene copies (genotype GCS/GCS or homozygous affected); they will always pass the mutated gene onto their offspring and should also be mated only to clear dogs.

	The DNA test
	By DNA testing, the responsible mutation can be shown directly. This method provides a very high accuracy test and can be done at any age. It offers the possibility to distinguish not only between affected and clear dogs, but also to identify clinically healthy carriers.   This is an essential information for controlling the disease in the breed, as carriers are able to spread the disease in the population, but can not be identified by means of common laboratory diagnostic. To ensure maximum test reliability, the test is always performed in two independent test runs per sample. This test allows a breeder to control the mutant gene frequency in the Collie breed thus preventing the production of puppies affected with Canine Cyclic Neutropenia.

	Requirements
	The test is performed out of EDTA whole blood (0.5 ml) or special cytobrushes. These cytobrushes are available upon request and free of charge. Testing is performed a few times per week. The results are due about 3-5 working days after arrival of the sample in our laboratory.   Please inquire for the exact cost of the test; we give discounts if several samples are sent at the same time: 15% off for 3 and more samples, and 30% off for 6 and more samples. If we have an agreement with a breeding club, members of this club get a reduced price.

	For further information please contact:
	Dr. Petra Kühnlein or Dr. Ines Langbein-Detsch LABOKLIN GmbH and  Co.KG Steubenstraße 4 D-97688 Bad Kissingen  / Germany    Phone: +49-971-72020 /72020 or Fax: +49-971 / 7202995  Email:   labogen