Cyclic Neutropenia (CN)
Canine cyclic neutropenia, also known as 'gray collie syndrome' (GCS), is an autosomal recessive disease. Both parents must carry the abnormal gene for the offspring to be affected. Carriers are perfectly healthy and do not manifest the disease, but if bred to another carrier there is the risk of producing an affected puppy.
This is a disorder in which the number of neutrophils, (the types of white blood cells that are primarily responsible for gobbling up invading bacteria and other infectious organisms) drops dramatically in a cyclical pattern, usually about every 10 to 12 days. During the time of a low neutrophil count, there is an increased susceptibility to infection. Affected dogs develop clinical signs such as fever, diarrhea, joint pain, or other signs associated with eye, respiratory, or skin infections. They are also prone to bleeding episodes.
GCS is a serious genetic disorder and affected puppies are smaller and weaker, with a noticeable pale gray or pinkish/gray or beige color. These puppies rarely live beyond a couple of days and when they do survive, they are susceptible to all sorts of infections. With proper treatment they can be kept alive, but few have lived beyond 2 to 3 years of age.
The dog has 2 copies of the normal gene and will neither develop the disease,nor pass a copy of the cyclic neutropenia gene to any of its offspring.
The dog has one copy of the normal gene and one copy of the mutantgene that causes cyclic neutropenia. It will not develop the disease butwill pass on the mutant gene to 50% (on average) of its offspring.
The dog has two copies of the cyclic neutropenia mutation and is affected with the disease.