TNS is an hereditary diesease where bone marrow produces neutrophils (white cells) but is unable to effectively release them into the blood stream.
Affected puppies have an impaired immune system and will eventually die from infections they cannot fight.
Most affected puppies die or are euthanized by about 4 months of age.
It is important to understand a carrier is not affected by this disease but if bred with another carrier puppies will be affected. A mating between a carrier and a clear dog will result in some puppies being clear and others being carriers but no puppies will be affected. When both parents are clear all puppies will be clear by parentage