There are currently 3 hereditary diseases that affect Irish Setters.
All of these diseases have impacted on the breed overseas, leading to development of genetic tests through extensive research.
PRA (rcd1), PRA (rcd4) and CLAD are inherited quite independently and each has an autosomal recessive mode of inheritance, so any affected animal must have two defective genes for the particular disease – one from each parent.
It is important to understand that the tests are specific gene tests so results are unequivocal: dogs/bitches are classified with certainty as clear, carrier or affected. This makes it possible to prevent the disease in offspring with selective breeding. The elimination of the causative genes and by using Clear parents allows the need for further testing in offspring generations to be delayed. These dogs are given the status of ‘Clear by parentage’.
- Clear dogs have no copies of the recessive gene. They will never develop the disease nor will they pass it on to their offspring
- Carriers have one copy of the defective gene and one copy of the normal gene. They will not develop the disease but may pass a defective gene on to a proportion of their offspring.
- Affected dogs have two copies of the mutant gene that causes the disease and will develop the disease.
Progressive Retinal Atrophy (PRA)
Progressive Retinal Atrophy (PRA) is an untreatable, irreversible, inherited eye disease that causes degeneration of the retina and leads to complete blindness.
While PRA has a number of forms and affects many breeds. Irish Setters suffer from an ‘early onset’ kind of PRA known as rod-cone dysplasia 1 or rcd 1.
More recently late onset PRA, a mutation has been discovered known as rcd4.
- Irish Setter PRA (rcd1) is unique in its early onset with affected animals becoming blind at an early age.
- Irish Setter PRA (rcd4) has a later onset with affected animals becoming blind at an older age.
- Both forms of PRA are passed on by a separate simple autosomal recessive gene.
Canine Leucocyte Adhesion Deficiency (CLAD)
Canine Leucocyte Adhesion Deficiency (CLAD) is a recessive genetic disorder that results in a fatal immunodeficiency disease in which affected puppies die due to multiple and intractable bacterial or viral infection. CLAD was first identified in the USA.
In 1999, the mutation causing CLAD in Irish Setters was identified and a genetic test developed. CLAD can be difficult to diagnose so the simple once-only test is a significant development as use of the test will enable breeders to eliminate the risk of producing affected dogs.
The test accurately identifies clear, carrier and affected animals.
- Clear dogs have no copies of the CLAD gene. They will never develop the disease nor will they pass it on to their offspring.
- Carriers have one copy of the defective CLAD gene and one copy of the normal gene. They will not develop the disease but may pass a defective gene on to a proportion of their offspring.
- Affected dogs have two copies of the mutant gene that causes CLAD and will develop the disease.
The Irish Setter Club of Victoria has a database of certified results for Irish Setters under ISCV Inc. Genetic Register on this website. This is voluntary system and not all Irish Setter results have been submitted.
ANKC members, including our club members are bound by the ANKC National Code of Practice for hereditary diseases and ANKC Ltd Protocols for DNA -based Disease Testing.
Before any puppy or adult animal is sold, the prospective owners should be advised that the seller has taken all reasonable steps to comply with the Code of Practice. This may be a copy of certified results, DNA test results showing parentage or pedigree showing parentage certified results should be available for viewing when purchasing an Irish Setter
Submission of authorised results can be made to the
Officer for the ISCV INC. Genetic Register
C/- Graham Hill Eyecare
P. O. Box 774
Officer for the ISCV INC. Genetic Register; Rhonda Fisher