Cardiomyopathy and Juvenile Mortality

General Information: Cardiomyopathy and Juvenile Mortality (CJM) is an inherited condition in dogs that leads to early mortality due to heart failure. Puppies as young as 6 weeks old may show symptoms such as tremors, gastrointestinal issues, and difficulty breathing. Diagnostic x-rays can reveal an enlarged heart and potentially a narrowed trachea, indicating severe cardiac and respiratory issues. The underlying cause involves degenerative changes in the heart muscle, likely resulting from abnormal cellular metabolism. Sadly, affected puppies typically do not survive past 8 weeks of age, succumbing to heart failure.

How to Read Your Dog's Test Results for this Genetic Variant:

Two Variants Detected: Dog Likely Affected

One Variant Detected: Dog Unlikely Affected

No Variants Detected: No Effect

Gene / Testing Information: Genetic testing of the YARS2 gene can identify the presence of the variant for Cardiomyopathy and Juvenile Mortality (CJM), an autosomal recessive disease. This means that to be affected, a dog must inherit two copies of the mutated genetic variant (one from each parent). Carrier dogs possess one copy of the variant and do not exhibit any symptoms, but they can pass the mutation on to their offspring. When two carriers are bred, each puppy has a 25% chance of inheriting the disease and a 50% chance of being a carrier. To prevent the continuation of this condition in the gene pool and avoid the birth of affected puppies, it is crucial not to breed two known carriers. By employing responsible breeding practices based on reliable genetic testing, breeders can help eliminate this mutation from breeding lines and reduce the occurrence of this fatal condition.