Canine Leukocyte Adhesion Deficiency (CLAD) is an inherited immunodeficiency condition which affects the white blood cells ability to fight infection. Affected puppies show infections from a very early age, often with umbilical (navel) infections from birth with other recurring infections of skin, mouth and sores that do not heal. There may be tonsillitis, pneumonia as well as joint and bone problems. These infections usually respond well to antibiotics but, as soon as they are stopped, the infections return. Inflammation of the gums occurs when the pups are about 2 months old along with swollen jaws. Some joints become swollen, in some cases so much so that movement is difficult. Although it affects different pups to varying degrees CLAD is inevitably fatal.
CLAD is identical to human LAD and bovine LAD and this helped research as it was known that the mode of inheritance is by a single recessive mutation in a gene that is responsible for controlling a vital part of the function of the white blood cells. This means that puppies have to inherit two copies of the mutant gene, one from its dam and one from its sire. Research on the disease was carried out in England and Scandinavia, where the carrier rate was close to 12%. That meant that 12% of the tested population of Irish Setters was not suffering from and never would suffer from the disease but could pass on the mutant gene to its pups. Affected dogs are likely to die before reaching breeding age, but mating of two carriers will produce, on average, one affected, two carriers and one clear progeny for every 4 pups.
Irish Setters now have a DNA test for CLAD which has, over time, allowed breeders to apparently eliminate the problem from the breed in UK. No Irish setter that has been tested for CLAD since 2007 has been found to be either a carrier or affected. Unless a case is made to the KC for exceptional circumstances then no puppy can be registered with the Kennel Club unless it is either hereditarily clear or tested clear.
It is important that if you are considering buying a puppy you check with the breeder to confirm that both the sire and the dam have been DNA tested clear or are hereditarily clear. If not, then the puppy himself needs to have been DNA tested. If not, we recommend you do not buy the puppy. The information is clearly shown on the puppy’s Kennel Club registration papers.
Follow the link to see the list of Irish Setters tested for CLAD in UK, however it does not show the Irish that are hereditarily clear of the condition.
An Irish Setter dog was imported to UK in 2016 and is confirmed as being a CLAD carrier and we believe there is a second imported dog that is also a CLAD carrier. Neither of these dogs appear on the Kennel Club register of dogs DNA tested for CLAD. In UK it is very easy to become complacent and believe this problem no longer exists but it obviously does. Responsible breeders do not want CLAD to become a problem in the breed again so please check that your puppy or potential sire is CLAD clear.
One of these CLAD carriers has recently been used at stud and therefore, statistically, 50% of his puppies will be carriers increasing the number of carriers in UK.
- Immune Deficiency in the Irish Setter (Granulocytophy) SEISC Southern Aspect 1990/1991
Dr Gunilla Trowald-Wigh
- Irish Setter Club of Wales Memorial Lecture 22/2/98
Speaker Dr Gunilla Trowald- Wigh, veterinary clinician from Uppsala University
- Leucocyte adhesion protein deficiency in Irish Setter dogs 1999
Dr Gunilla Trowald –Wigh, Lena Hakansson, Anders Johannisson, Leif Norrgren and Carl Hard af Segerrstad
- Canine Leucocyte Adhesion deficiency (CLAD) in the Irish Setter 2000
Dr Jeff Sampson KC Canine Genetics Co ordinator