Glycogen Storage Disease III

Test Overview:

The glycogen storage diseases (GSD) are a group of autosomal recessive disorders of glycogen metabolism. Glycogen is the storage form of glucose in tissues. It is catabolised in the organism to glucose-1-phosphate if needed. GSD IIIa is a deficiency of glycogen debranching enzyme activity (GDE) which results in glycogen accumulation in liver and muscles. The clinical signs appear to be mild in the first year of life, becoming more prominent with age and leading to lethargy, exercise intolerance and episodic hypoglycemia with collapse.


Metabolic - Associated with the enzymes and metabolic processes of cells


Amylo-alpha-1, 6-glucosidase, 4-alpha-glucanotransferase (AGL) on Chromosome 6

Variant Detected:

Nucleotide Deletion c.4223delA p.frameshift


Moderate. This disease can cause significant signs of discomfort and/or dysfunction in affected animals. It may involve relatively high treatment/management costs, and can sometimes reduce life expectancy.

Mode of Inheritance:

Autosomal Recessive

Recommended Screening:

1. DNA test all breeding animals prior to entering into a breeding program (e.g. at 1 year old).

Research Citation(s):

Gregory, BL. et al. Glycogen Storage Disease Type IIIa in Curly-Coated Retrievers (2007) J Vet Intern Med, 21(1);40-46.

Associated Breed(s):

Curly Coated Retriever, Mixed Breed,