Canine Leukocyte Adhesion Deficiency (CLAD) Test
For: Irish Setters and Irish Red & White Setters
Please note cheek swabs are not accepted for this test.
Technically known as Canine Leukocyte Adhesion Deficiency, this rare but devastating condition is an inherited fatal immunodeficiency disease. Pups that inherit two recessive genes for CLAD usually die early in life from multiple severe infections, even when treated with massive doses of antibiotics.
CLAD is related to the same disease in humans (LAD) and cattle (BLAD). So far, CLAD has been found only in Irish Setters. Research on the disease was carried out in England and Scandinavia, where the carrier rate is close to 12%. However, CLAD was first identified clinically in the United States.
Reliable identification of dogs that do not carry disease genes is the key to eliminating autosomal recessive diseases such as CLAD. Now OptiGen offers a new DNA-based test that provides a method to eliminate Canine Leukocyte Adhesion Deficiency, or CLAD from the Irish Setter.
As a mutation-based gene test, the OptiGen CLAD test unequivocally and specifically identifies normal dogs. Called "genetically clear," "noncarriers" or, more formally, "homozygous normals," such dogs can pass only the gene for normal leukocyte (white blood cell) function on to all their pups.
The test also identifies carriers (heterozygous dogs) with 100% accuracy. These carriers can be safely bred to "clears." Their recessive genes can only cause disease when matched with the recessive gene of another carrier. Performed early enough, this test will accurately identify affecteds as well. But affecteds usually don't survive to breeding age.
It isn't necessary to remove those carriers which are otherwise excellent dogs from the breeding population. But given the lethal nature of the disease, it is best to select against carriers who are not superlative dogs, so as to entirely eliminate the gene from a line within two or three generations.
How you can participate...
The rcd1-PRA test and the CLAD test for the Irish Setter are done on a small sample of blood obtained by your veterinarian. This allows the lowest risk of contamination of the sample and added assurance of a match of the sample with the identified dog. No sampling kit is needed.
Read and print the instructions on the Ship Sample page. Then fill out the Test Request Form. On-line submission of the Test Request Form lets you be sure accurate information and correct spellings are put in the database. And, when you've completed one Form, a second Test Request Form for another dog or for a litter is easy and saves you time.
The research leading to the rcd1-PRA gene test was published in 1994 in Investigative Ophthalmology & Visual Science. The patented technology underlying the CLAD test was discovered by scientists at Uppsala University, Sweden, and is under exclusive license to OptiGen. PCR technology is performed under a license agreement with Roche Molecular Systems, Inc.
Irish Red & White Setters – Testing for PRA and CLAD
The DNA-based genetic tests for the rcd1 form of Progressive Retinal Atrophy (PRA) and for Canine Leukocyte Adhesion Deficiency (CLAD) are identical for both Irish Setters and Irish Red & White Setters. The information given above on this page for Irish Setters therefore can be applied to Irish Red & Whites as well.
As more Irish Red & Whites are screened for the rcd1-PRA mutation with the DNA test, we will generate an estimate of the mutation frequency.
CLAD has been reported in Irish Red & Whites in Europe and recent screening done there for the CLAD mutation confirms that the mutation is in these lines. Out of 76 Irish Red & Whites screened, six were carriers with the CLAD mutation. (reported by Debenham, Millington, Kijas, Andersson and Binns, Journal of Small Animal Practice. Vol 43, February 2002.) Again, as more dogs are tested, an estimate of mutation frequency will be generated specifically for the US.
Registration with CERF of the DNA test results for Irish Red & White Setters is not addressed in the general guidelines of the IRWSA.