Basset Hounds can suffer from a glycogen storage disease (GSD) caused by a genetic variant in the RBCK1 gene. This autosomal recessive disorder leads to abnormal glycogen accumulation. Clinical signs typically begin between 8 and 12 months of age with chronic vomiting and diarrhea. As the disease progresses, affected dogs may develop muscle weakness, cardiac complications, and an increased risk of sudden cardiac death
Detailed description
Glycogen storage diseases are a rare group of inherited metabolic disorders characterized by defects in enzymes responsible for glycogen synthesis, degradation, or regulation. These deficiencies result in abnormal glycogen accumulation, particularly in tissues with high glycogen turnover such as the liver, cardiac muscle, skeletal muscle, and smooth muscle
In Basset Hounds, a genetic variant in the RBCK1 gene has been identified. RBCK1 encodes a subunit of an E3 ubiquitin ligase involved in inflammatory and immune responses. Deficiency of this protein leads to the accumulation of abnormal glycogen in the form of polyglucosan bodies. In humans, variants in RBCK1 are associated with polyglucosan body myopathy type 1 (PGBM1), a condition marked by skeletal muscle myopathy, cardiomyopathy, and polyglucosan accumulation
Affected dogs typically show gastrointestinal problems (chronic vomiting and diarrhea) beginning between 8 months and one year of age. By around three years, they may develop progressive muscle weakness, exercise intolerance, congestive heart failure, and are at risk of sudden cardiac death
Early clinical signs are subtle, often limited to mildly elevated CK levels. In later stages, measurable increases in CK, AST, and cardiac troponin indicate ongoing cardiac damage. Postmortem histopathology reveals extensive glycogen accumulation in the heart, leading to severe myocardial degeneration and necrosis, as well as glycogen deposition in smooth muscle of the gastrointestinal tract
