Canine Leukocyte Adhesion Deficiency (CLAD) is an autosomal recessive mutation that affects Irish Setters and Irish Red and White Setters. Autosomal recessive mutations are mutations that can be passed from either parent and require two copies of the gene to show symptoms.
The mutation prevents white blood cells from adhering to, and eliminating, harmful bacteria and viruses. This has a direct impact on the dog’s immune system. White blood cells, also known as leukocytes, do not function properly. The immune system cannot fight off infections. Affected puppies will develop multiple infections. Most often, they develop gum and umbilical infections and die fairly quickly.
It is estimated that over 10% of Irish Setters are carriers of the mutation. Because CLAD is a recessive disorder, a dog must have two copies of the mutation in order for the disease to manifest. This means that a dog can have one copy of the mutation and not experience any signs or symptoms of CLAD. This dog would be known as a carrier. The carrier can then pass on either the normal gene or the mutated gene to any offspring. If two carriers are bred, there is a 25% per puppy that they will develop symptoms of CLAD.
|Affected: Dog has two copies of the mutation associated with CLAD and will display symptoms of the disorder. The gene will always be passed off to any offspring.
|Carrier: Dog has one copy of the CLAD mutation. The dog is not affected by the disorder but may pass on the mutation to offspring.
|Negative: Dog is negative for the mutation associated with CLAD.
Boudreaux MK, Wardrop KJ, Kiklevich V, Felsburg P, Snekvik K. (2010) A mutation in the canine Kindlin-3 gene associated with increased bleeding risk and susceptibility to infections. Thromb Haemost. 103(2):475-477.
Kijas JM, Bauer TR Jr, Gäfvert S, Marklund S, Trowald-Wigh G, Johannisson A, Hedhammar A, Binns M, Juneja RK, Hickstein DD, Andersson L. (1999) A missense mutation in the beta-2 integrin gene (ITGB2) causes canine leukocyte adhesion deficiency. Genomics 61, 101–110.