What Your Test Results Mean:

Carriers typically show no symptoms of aspartylglucosaminuria; however, carriers are at an increased risk of having a child with aspartylglucosaminuria. Risk for the current or future pregnancies is dependent on your partner’s carrier status. Carrier testing of your partner is recommended in addition to consultation with a genetic counselor.

Disease Explained:

Aspartylglucosaminuria is an inherited lysosomal storage disorder caused by a deficiency of the enzyme aspartylglucosidase. Aspartylglucosidase is found in lysosomes, the recycling compartments in the cells of the body. Without this enzyme, carbohydrates accumulate and cause cell death and tissue damage. Aspartylglucosaminuria causes progressive decline in mental functioning, coarse facial features, and skeletal abnormalities. Bone marrow transplant has been attempted with mixed results and enzyme replacement therapy is not yet clinically available.

How the Genetics Works:

Aspartylglucosaminuria is an autosomal recessive disorder caused by pathogenic variants in the AGA gene. In general, individuals have two copies of the AGA gene. Carriers of aspartylglucosaminuria have a single variant in one copy of the AGA gene while individuals with aspartylglucosaminuria have variants in both copies of their genes, one inherited from each parent. Risk for two carriers to have a child with the disorder is 25%.