A number of tests are available for the Australian Shepherd. Two or more of these tests purchased as part of this bundle will be discounted.
- Chondrodysplasia (CDPA) associated with the FGF4 -18 retrogene insertion
- Chondrodystrophy (CDDY) with risk of IVDD associated with the FGF4-12 retrogene insertion.
- Collie Eye Anomaly associated with the NHEJ1 gene
- Degenerative Myelopathy associated with the SOD1 gene
- Hereditary Cataract associated with the HSF4 gene
- Hyperuricosuria associated with the SLC2A9 gene
- Multi-Drug Resistance associated with the ABCB1 gene
- Progressive retinal atrophy associated with the PRCD gene
Chondrodysplasia (CDPA) is shortened long bones, resulting in dogs with short legs.
A partial copy of the FGF4 gene has been inserted (FGF4-18, a retrogene insertion) on chromosome 18 and is associated with CDPA. Evidence that suggests that any dog with one or two copies of FGF4-18 will have short legs. Unlike CDDY, CDPA is not associated with any disease.
Chondrodystrophy (CDDY) with risk of IVDD
Chondrodystrophy (CDDY) in dogs is defined by dysplastic (abnormal), shorted long bones (short legs) and premature degeneration and calcification of intervertebral discs. Chondrodystrophic breeds are prone to a type of disc degeneration called chondroid metaplasia, where the discs become hardened and less able to flex with movement and therefore more prone to bulging or rupture i.e. Intervertebral Disk Disease (IVDD). The calcified inner disc material also puts pressure on the spinal cord, causing pain and damage to the nerves running through the spinal cord. Dogs may suffer from severe pain, inability to urinate or defecate, paralysis and even death. Many affected dogs are treated by surgically removing the prolapsed disc.
A partial copy of the FGF4 gene has been inserted (FGF4-12, a retrogene insertion) on chromosome 12 and is associated with CDDY. Evidence that suggests that any dog with one or two copies of FGF4-12 will be affected with CDDY, will have short legs and will be predisposed to IVDD. However, not all dogs with FGF4-12 will go on to develop IVDD.
Collie Eye Anomaly
*Optigen Officially Licensed*
Collie Eye Anomaly/Choroidal Hypoplasia (CEA/CH) is a developmental defect of the eye. Specifically, the abnormal development of the choroid – an important layer of tissue under the retina of the eye – in which there is a decrease in the development of the blood vessels. Puppies can be diagnosed by an ophthalmologist as early as 6-8 weeks of age. As the puppies get older the tapetum (the reflective layer at the back of the eye) develops and this can hide the signs of CEA. This phenomenon is called “go normal”, but it does not mean that CEA goes away or gets better. Affected dogs can also develop optic disc coloboma and retinal detachment.
Important: Degenerative Myelopathy is a rare disease that presents most commonly in German Shepherd Dogs and Boxers, sporadically in Pembroke Welsh Corgis, Cardigan Welsh Corgis, Bernese Mountain Dogs, Rhodesian Ridgebacks, Borzoi and Chesapeake Bay Retrievers. It is rarely diagnosed in other breeds or mixed-breed dogs. DM is considered genetically complex and will have more than one contributing genetic variant. The variant targeted by this test is widespread and found in more than 120 breeds. However, association of the variant with the disease has only been shown in very few breeds and should never be used to inform breeding decisions, except where close relatives have been clinically diagnosed.
Canine degenerative myelopathy (previously also known as chronic degenerative radiculomyelopathy) is a progressive disease of the spinal cord in older dogs. Most dogs are at least 8 years old before clinical become apparent. DM usually starts with a muscle weakness, loss of muscle and loss of coordination (ataxia) in the hind limbs. Progression is generally quote slow, but dogs will eventually be crippled within approximately 3 years of the onset of disease.
Cataracts are a leading form of blindness in the dog. Cataracts associated with an HSF4 deletion, specific to Australian Shepherds, usually appear early in life, but can also appear later. The cataracts will progress to complete blindness if the dogs live long enough and the only effective treatment is a surgical intervention. Dogs that carry (have one copy) of the HSF4 deletion are 17 times more likely to develop binocular cataracts than dogs without the variant.
The SLC2A9 gene codes for a protein that allows the kidneys to transport uric acid from the urine. Dogs with mutations in both copies of the SLC2A9 gene are predisposed to have elevated levels of uric acid in the urine, hence the name hyperuricosuria. Dogs with hyperuricosuria most commonly present with symptoms of recurrent urinary tract inflammation, which include frequent urination, blood in the urine, and straining to urinate. They may also have loss of appetite, lethargy, weakness, vomiting and pain. Urinary stones in the bladder can cause urinary tract infections or more seriously, blockage of the Urethra.
Both male and female dogs can be affected, but due to differences in their anatomy obstruction of urine flow is more common in males. Although an x-ray can be used to exclude other types of stones, urate stones cannot typically be seen using x-rays and must be evaluated by ultrasound. Not all dogs with mutations in both copies of the SLC2A9 gene will have symptoms of disease, thought they will have increased uric acid excretion in the urine.
In certain breeds a mutation on the ABCB1 gene, which encodes the MDR1 protein (which stands for Multi Drug Resistance 1) can cause animals that carry the mutation to be particularly sensitive to certain drugs. The variant was first detected in a subpopulation of dogs that were highly sensitive to Ivermectin-induced neurotoxicity. The variant on the ABCB1 gene results in the brain being unable to efficiently pump some drugs out, causing a toxic build-up of these drugs in the brain. Dogs subsequently experience and range of symptoms from vomiting and diarrhea to lethargy, seizures, or coma.
Progressive retinal atrophy (PRCD type)
*Optigen Officially Licensed*
Progressive retinal atrophy (PRA) is the most common form of inherited disease affecting the retina in dogs. Genetically different forms of PRA, caused by mutations in different genes, affect many breeds of dog with each form usually affecting one or a small number of breeds. PRA is characterised by progressive degeneration of the retina at the back of the eye and leads to vision loss and blindness.
Progressive Rod Cone Degeneration (PRCD) is a form of PRA and was one of the first PRAs for which a genetic variant was identified. PRCD is different than most forms of PRA in that the variant has been found in a large number and diverse range of breeds.