Genetic basis - Genetic testing for the AGL gene mutations is recommended for Curly Coat Retriever breeding dogs to identify carriers and affected animals. Dogs homozygous for mutations should not be bred to avoid affected offspring. Carriers can be bred only to clear dogs to minimize risk of affected puppies while maintaining genetic diversity. Avoid breeding two carriers together to reduce incidence. Sharing genotype data among breeders promotes responsible breeding choices.
Pathophysiology - Deficiency of the glycogen debranching enzyme leads to incomplete glycogen breakdown, resulting in accumulation of abnormal glycogen in liver, skeletal muscle, and cardiac muscle cells.Excess glycogen impairs normal tissue function, causing liver enlargement (hepatomegaly), hypoglycemia (low blood sugar), muscle weakness, and potential heart problems.
Complications - Symptoms usually appear in early life with hypoglycemia, failure to thrive, hepatomegaly, and elevated liver enzymes. Muscle weakness and cardiomyopathy typically develop later in life as the disease progresses. Liver size often normalizes or improves in adolescence but some dogs may develop liver cirrhosis or failure. Progressive muscular disease can cause exercise intolerance, fatigue, and sometimes cardiac complications. The disease is chronic and lifelong, with supportive care managing symptoms.
Why This Matters to Breeders and Vets - For breeders, identification of carriers prevents propagation of this serious metabolic disorder, improving breed health and longevity. Veterinarians use understanding of GSD IIIA for early diagnosis, monitoring, and management of affected dogs. Awareness of autosomal recessive inheritance aids in genetic counseling and breeding strategies. Early diagnosis and supportive care help improve affected dogs' quality of life.
