Degenerative Myelopathy caused by Mutation of the SOD1 gene is an inherited neurologic disorder of dogs. This mutation is found in many breeds of dog, including the Rhodesian ridgeback. While it is not clear for some of the other breeds, Rhodesian ridgebacks are known to develop degenerative myelopathy associated with this mutation. The variable presentation between breeds suggests that there are environmental or other genetic factors responsible for modifying disease expression. The average age of onset for dogs with degenerative myelopathy is approximately nine years of age. The disease affects the White Matter tissue of the spinal cord and is considered the canine equivalent to amyotrophic lateral sclerosis (Lou Gehrig’s disease) found in humans. Affected dogs usually present in adulthood with gradual muscle Atrophy and loss of coordination typically beginning in the hind limbs due to degeneration of the nerves. The condition is not typically painful for the dog, but will progress until the dog is no longer able to walk. The gait of dogs affected with degenerative myelopathy can be difficult to distinguish from the gait of dogs with hip dysplasia, arthritis of other joints of the hind limbs, or intervertebral disc disease. Late in the progression of disease, dogs may lose fecal and urinary continence and the forelimbs may be affected. Affected dogs may fully lose the ability to walk 6 months to 2 years after the onset of symptoms. Affected medium to large breed dogs, such as the Rhodesian ridgeback, can be difficult to manage and owners often elect euthanasia when their dog can no longer support weight in.
Genetic testing of the gene in RR's will reliably determine whether a dog is a generic carrier of DM. DM is inherited in an autosomal reccessive manner in dogs meaning that they must receive two coppies of the mutated gene (one from each parent) to develop the disease.
Carrier dogs do not have features of the disease but if bred to a another carrier there is a risk of producing affected puppies. Reliable genetic testing is important for determining breeding practices & selecting the correct sire or dam as what we are avoiding is producing affected dogs not avoiding the carriers. Genetic testing should be performed before breeding.
Carrier dogs do not have features of the disease but if bred to a another carrier there is a risk of producing affected puppies. Reliable genetic testing is important for determining breeding practices & selecting the correct sire or dam as what we are avoiding is producing affected dogs not avoiding the carriers. Genetic testing should be performed before breeding.
What is colour dilution?
There's a wide variety of genes that influence coat color in dogs. Only some genes are identified using DNA. The dilution series is a relatively simple series.
This locus is classically known as the D locus and contains the melanophilin gene (MLPH). There are two allels at the dilute locus, which are called D (dominant, full pigmentation) and d (recessive, dilute pigment). Coat color dilution is inherited as monogenic recessive trait and is displayed by dogs with the genotype dd, whereas dogs with the genotype DD or Dd show the normal coat color. Again it importmant to DNA test for dilute so we can avoid breeding a fault coloured dog.