One of the happiest days of my life was bringing home a German shepherd puppy to join our family. Like many parents, my wife and I wanted our only son Brandon, who was 5 or 6 years old at the time, to grow up around dogs and help us teach him some responsibility. We visited a family with a litter of 7 week old puppies to let Brandon pick the one that was going to be his buddy while he grew up. Brandon decided on the quietest pup in the litter to become our new dog, Griffey. Our journey with Griffey (Griff for short) began with Brandon and his new companion in the back of our convertible in route to the home we were excited to share with our new family member. My wife and I were hopeful that Griff would give Brandon a best friend for 10 to 13 years. Unfortunately, that wasn’t exactly how things worked out.
Signs of Trouble
We spent many years loving Griff and giving him the best years of his life. Brandon and Griff were inseparable as they aged. They played together, they napped together, and they got into trouble together. At about 8 years old, Griff started to have problems getting up in the hind end after lying down. We knew about hip dysplasia in the German shepherd and suspected that perhaps Griff was showing signs of the condition. We took Griff to a nice veterinarian who agreed that hip dysplasia or arthritis were possibilities for Griff, but stated he would not know for certain without performing x-rays. Unfortunately, the x-rays failed to provide an explanation for what we were seeing. Despite this, the veterinarian we saw suspected that Griff might be experiencing pain. As a trial, he prescribed some anti-inflammatory pain medication in an effort to help. We gave Griff his medications as prescribed, but failed to see an improvement. When we returned to the vet a month or so later to report Griff’s poor response to medication, the vet informed us that Griff was “8 years old and maybe just slowing down.” My wife and I were shocked. We had dogs in the past and never had an 8 year old dog just “start to slow down” as he described. We started talking to people familiar with the breed (this was before the internet and all the websites we have today) and learned about a progressive, neurological disease of the German shepherd called degenerative myelopathy (that is now known to occur in many breeds). We were told that there was no testing available for living animals at the time, but there was research being done. Much to our dismay, Griffey’s breed, his lack of response to pain medication, normal results on diagnostic testing, and progressive neurological dysfunction starting in the hind limbs all fit with a diagnosis of degenerative myelopathy (DM).
At the time, DM was not on our veterinarian’s radar until we brought up what we had learned from others (though most veterinarians are familiar with the condition today, some still do not realize that it also occurs frequently in breeds outside of the German shepherd). Similar to Lou Gehrig’s disease (also known as amyotrophic lateral sclerosis or (ALS) in humans), this devastating disease quickly turned our lives upside down. In less than a year, Griff went from being a vibrant part of our family to needing help to get up or walk down stairs and was eventually unable to hold his bowels. We took him back and forth to the vet several times before we ultimately had to make a decision in regards to Griff’s quality of life. As tough as the decision was, after nearly 9 years with a family member that brought us such unconditional love and joy, we knew we had to help Griff end his suffering. As expected, Griff’s best friend Brandon took it the hardest. Unfortunately, no one gives us instruction on how to tell a 14 year old boy that his best friend is going to the vet for the final time and that he will never get another chance to hug him, pet him, share his dinner with him, or just be there as his friend. We all wished at the time that there was something that could be done to prevent any other child from having to experience the premature loss of a dog due to degenerative myelopathy. Some 12 years later, after accepting a new job with the canine genetic disease testing company, Paw Print Genetics, I learned that genetic testing was available to prevent families from experiencing what we had endured.
Preventing Degenerative Myelopathy
The 2009 discovery of a mutation responsible for causing DM allowed for the development of genetic testing that can be used by breeders to identify DM carriers (those dogs that have inherited one copy of the mutation and will not show signs of disease themselves, but can produce affected puppies). It should be noted that DM displays a phenomenon known as incomplete penetrance which means that some dogs which inherit two copies of the mutation will not go on to develop clinical signs of DM. The percentage of dogs with two copies of the mutation that will become affected is unknown and likely influenced by breed, bloodline, and other unknown environmental and genetic factors. Since these factors are not yet understood, the only way to reliably prevent producing affected puppies is to only breed carrier dogs to those that have not inherited the mutation (clear or normal).
Like Griff, most dogs that develop DM begin showing signs of the disease around 7 to 10 years of age. Most affected dogs become completely paralyzed within 2 years of showing their first clinical signs. Since there is no definitive clinical or pathological test for DM in the living dog, it is a disease that must be diagnosed through the exclusion of other diseases. Unfortunately, in addition to the emotional toll of DM, many people (my family included) often spend hundreds or thousands of dollars on diagnostic testing to diagnose a disease that can now be identified for around the price of a dinner for two at a nice restaurant. Thus, today, dogs can be tested by obtaining a sample with a cheek swab from which DNA is extracted and the mutation associated with DM can be identified in the DNA. Once identified, informed breeding can eliminate the possibility of producing puppies with the disease.
Contact Paw Print Genetics
If you have questions about testing your dog or eliminating degenerative myelopathy from your breeding program, please contact Paw Print Genetics at AskUs@pawprintgenetics.com or simply call our laboratory at 509-483-5950 to speak to one of our veterinarians or geneticists.