Glycogen storage disease type 1a (GSD1a)


Glycogen storage disease type 1a (GSD1a, MIM 232200), also known as Von Gierke disease, is an autosomal recessive inborn error of glycogen metabolism, occurring in ~1/100,000 live births worldwide. The condition usually manifests during the first year of life with severe hypoglycemia, growth retardation, hepatomegaly, bleeding diathesis, lactic acidemia, hyperlipidemia and hyperuricemia. Long-term complications include gout, hepatic adenomas, osteoporosis and renal disease. GSD1a is caused by a deficiency of the enzyme glucose-6-phosphatase (G6Pase), which has an important role in glycogen metabolism and blood glucose homeostasis. G6Pase is normally expressed in the liver, kidney and intestinal mucosa and absence of G6Pase activity is associated with the excessive accumulation of glycogen in these organs. A clinical diagnosis of GSD1a can be confirmed by enzyme analysis on a liver biopsy. The G6PC gene consists of 5 exons and family specific mutations are found throughout the gene, however, ethnic specific mutations are recognised and information regarding ethnic origin is a useful indicator. In the North European Caucasian population two mutations, namely p.Gln347X and p.Arg83Cys account for approximately 62% of all mutations.

Also known as

Von Gierke disease, glucose-6-phosphatase deficiency

Request a test

When requesting this test please use the referral form provided. Please also refer to any additional information provided for this test.

Additional information

Clinically affected patients can have their diagnosis confirmed by biochemical demonstration of a deficiency of G6Pase activity on liver biopsy. This should be arranged either locally or with the Enzyme Unit, Chemical Pathology, Great Ormond Street Hospital. Affected patients can be referred for mutation analysis. If the necessary patient samples are unavailable genetic testing can be undertaken in the parents of the affected child. Information regarding ethnic origin is useful. Carrier testing can be offered to the adult relatives of affected patients once a disease causing mutation has been identified.

Sending address

Rare & Inherited Disease Laboratory
London North Genomic Laboratory Hub
Great Ormond Street Hospital for Children
Levels 4-6 Barclay House
37 Queen Square

Laboratory service


Sample requirements

1ml EDTA neonates, 5ml EDTA adults

Reference range

Not applicable

Turnaround time

40 days

Disease / group



Upon request

Call in advance?

Prenatals must be arranged in advance, through a Clinical Genetics department if possible.


The Genetics Laboratories provide an extensive range of Cytogenetics and Molecular Genetics diagnostic testing services.

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