|Other Names:||Canine Leukocyte Adhesion Deficiency, CLAD, LAD-I|
|Breed(s):||Irish Red and White Setter, Irish Setter|
Leukocyte adhesion deficiency, type I is an inherited immunodeficiency disorder. Affected dogs have abnormal white blood cell (leukocyte) activity which results in a severely impaired immune system. Dogs usually develop symptoms shortly after birth and have recurrent infections throughout life. Symptoms include infections of the umbilicus, skin, bones, lungs and uterus as well as gingivitis, impaired wound healing, enlarged lymph nodes and low body weight. On blood work, affected dogs have persistently elevated white blood cell counts (leukocytosis). Without treatment puppies die within a few weeks of age. Even when treated with antibiotics, affected dogs will typically die by 6 months of age as a result of the recurrent and severe infections.
Genetic testing of the ITGB2 gene will reliably determine whether a dog is a genetic Carrier of leukocyte adhesion deficiency, type I. Leukocyte adhesion deficiency, type I is inherited in an Autosomal Recessive manner in dogs meaning that they must receive two copies of the mutated gene (one from each parent) to develop the disease. In general, carrier dogs do not have features of the disease but when bred with another carrier of the same Mutation, there is a risk of having affected pups. Each pup that is born to this pairing has a 25% chance of inheriting the disease and a 50% chance of inheriting one copy and being a carrier of the ITGB2 gene mutation. Reliable genetic testing is important for determining breeding practices. In order to eliminate this mutation from breeding lines and to avoid the potential of producing affected pups, breeding of known carriers to each other is not recommended. Dogs that are not carriers of the mutation have no increased risk of having affected pups.
There may be other causes of this condition in dogs and a normal result does not exclude a different mutation in this gene or any other gene that may result in a similar genetic disease or trait.
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