BANDERA’S NEONATAL ATAXIA (BNAT)
Bandera’s Neonatal Ataxia (also referred to as Bandera’s Syndrome) is a hereditary disease found only in the Coton de Tulear dog. This hereditary disease is named for the second Coton puppy diagnosed with the disease and results in affected puppies with an inability to coordinate their movements. This is due to a mutation in a glutamate receptor gene that affects neurotransmitter levels leading to improper brain signals and impeded movement coordination. Affected puppies can be recognized within the first few weeks as displaying difficulties walking, eating, standing and eliminating. There have been no known adult Cotons affected with Bandera’s Neonatal Ataxia.
CANINE MULTIFOCAL RETINOPATHY (CMR2)
The canine multifocal retinopathy mutation causes raised lesions to form on the retina which alters the appearance of the eye but usually does not affect sight. The lesions may disappear, or may result in minor retinal folding. Symptoms of the mutation usually appear when a puppy is only a few months old, and generally do not worsen over time. The genetic test for CMR is valuable for identifying the cause of a retinal deformation. Given the exact genetic diagnosis, the owner can be reassured that there probably will be little or no vision loss due to this condition.
While both CMR1 and CMR2 mutations are in the same gene, they are breed specific and testing for only one is required. The CMR2 mutation is specific for the Coton de Tulear breed. All other breeds listed should test for the CMR1 mutation.
CHONDRODYSTROPHY AND IVDD RISK (CDDY-IVDD)
Many dog breeds are defined by the presence of shortened legs that result from abnormal growth of cartilage and changes in the structure of growth plates. This leads to shortened leg bones that exhibit a bowed appearance. Two conditions have been described that cause shortened legs and are known as Chondrodysplasia (CDPA) and Chondrodystrophy (CDDY). CDDY is the second mutation that leads to shorter legs and more importantly can also put a dog at risk for premature degeneration of intervertebral discs known as Intervertebral Disc Disease (IVDD). The intervertebral disc sits between the vertebrae and allows for flexibility of the vertebral column. In dogs that carry the CDDY mutation, premature calcification can lead to degeneration of discs in dogs at a young age resulting in herniation, inflammation, and hemorrhage in the spinal cord. This can ultimately lead to severe pain and neurological dysfunction typical for IVDD
DEGENERATIVE MYELOPATHY (DM)
Degenerative Myelopathy (DM) is a progressive disease of the spinal cord in older dogs. The disease has an insidious onset typically between 8 and 14 years of age. It begins with a loss of coordination (ataxia) in the hind limbs. The affected dog will wobble when walking, knuckle over or drag the feet. This can first occur in one hind limb and then affect the other. As the disease progresses, the limbs become weak and the dog begins to buckle and has difficulty standing. The weakness gets progressively worse until the dog is unable to walk. The clinical course can range from 6 months to 1 year before dogs become paraplegic. If signs progress for a longer period of time, loss of urinary and fecal continence may occur and eventually weakness will develop in the front limbs. Another key feature of DM is that it is not a painful disease. Although any dog can be tested for DM, it is possible that the genetic background that predominates in some breeds prevents the development of symptoms even in dogs testing affected (at risk). At this time the required evidence of association between the genetic mutation and actual spinal cord evaluations has only been proven in the breeds listed.
This disease is characterized by the excretion of uric acid leading to the formation of urinary calculi (stones) which may then require surgery. If a dog from a breed susceptible to this disorder is seen to experience problems urinating freely, then veterinary advice should be sought immediately.
PRIMARY HYPEROXALURIA (PH)
Primary Hyperoxaluria (PH) is a metabolic disorder that affects the Coton de Tulear dog breed. The disease results from a liver enzyme deficiency required to break down calcium oxalate crystals so they can be eliminated from a dog’s system. Without a properly functioning enzyme, crystals build up in the dog’s body leading to progressive illness. Affected puppies show signs of the disorder at 3-4 weeks of age with the disease eventually leading to kidney failure. Symptoms of acute renal failure can include loss of appetite, vomiting, lethargy, decreased urine production, abdominal pain and blood in the urine. PH affected puppies rarely survive beyond a few months. This test includes PH1
PROGRESSIVE ROD-CONE DEGENERATION (PRA-PRCD)
Progressive retinal atrophy (PRA) is a category of different progressive conditions related to ¬retinal atrophy that can eventually lead to blindness. Progressive rod-cone degeneration (PRA-PRCD) is one specific type of PRA that affects many dog breeds. It is an inherited eye disease with late onset of symptoms that are due to degeneration of both rod and cone cells of the retina. These cells are important for vision in dim and bright light. Most dogs begin to show symptoms of the disease at approximately 3-5 years of age that manifests as difficulty seeing at night (night blindness) and loss of peripheral vision. Although rate of onset and disease progression can vary by breed, PRA-PRCD typically results in eventual loss of sight and complete blindness in affected dogs. It is important to note that other inherited eye disorders can display similar symptoms to PRA-PRCD.