X-SCID is a severe immunodeficiency, which results from abnormally low levels of lymphocytes (white blood cells) and their dysfunctionality. Lymphatic tissue of affected dogs is also underdeveloped. Affected dogs are extremely susceptible to opportunistic infections and typically die at a very young age.

Therapy is limited to symptomatic treatments for resulting infections and general supportive care. There is no cure.

There are many responsibilities to consider when breeding dogs. Regardless of test results it is important that your dog is in good general health and that you are in a position to care for the puppies if new responsible owners are not found. For first time or novice breeders, advice can be found at most kennel club websites.

This disorder is X-linked recessive, meaning the genetic variant is found on the X chromosome. Given males only have one X chromosome, a single affected copy will increase the risk of being diagnosed with the disorder. Females typically require two copies to be at an elevated risk for full clinical signs but are not generally seen due to the poor prognosis for affected males. Use of dogs with one or two copies of the variant is not recommended for breeding as there is a risk that the resulting litter will contain affected puppies. Please note: It is possible that clinical signs similar to the ones caused by this variant could develop due to a different genetic or clinical cause.