Reviewed October 2006
What is the official name of the GAA gene?
The official name of this gene is “glucosidase, alpha; acid (Pompe disease, glycogen storage disease type II).”
GAA is the gene's official symbol. The GAA gene is also known by other names, listed below.
What is the normal function of the GAA gene?
The GAA gene provides instructions for producing an enzyme called acid alpha-glucosidase (commonly called acid maltase). This enzyme is active in lysosomes, which are structures that serve as the cell's recycling center. Lysosomes use digestive enzymes that break down complex molecules into simpler ones that can be used by cells. Acid alpha-glucosidase normally breaks down a complex sugar called glycogen into a simpler sugar called glucose. Glucose is an important energy source for cells.
How are changes in the GAA gene related to health conditions?
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Pompe disease - caused by mutations in the GAA gene
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More than 100 mutations in the GAA gene have been identified in people with Pompe disease. Most of these mutations change one or more of the protein building blocks (amino acids) used to make acid alpha-glucosidase, reducing the activity of the enzyme significantly. When this enzyme is not active, glycogen builds up inside lysosomes and cannot be broken down into glucose. The abnormal buildup of glycogen within cells causes severe damage to many tissues, particularly muscle cells.
Where is the GAA gene located?
Cytogenetic Location: 17q25.2-q25.3
Molecular Location on chromosome 17: base pairs 75,689,876 to 75,708,272
The GAA gene is located on the long (q) arm of chromosome 17 between positions 25.2 and 25.3.
More precisely, the GAA gene is located from base pair 75,689,876 to base pair 75,708,272 on chromosome 17.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about GAA?
You and your healthcare professional may find the following resources about GAA helpful.
- Educational resources - Information pages
- Gene Tests
- DNA tests ordered by healthcare professionals
You may also be interested in these resources, which are designed for genetics professionals and researchers.
- PubMed - Recent literature
- OMIM - Genetic disorder catalog
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What other names do people use for the GAA gene or gene products?
- acid alpha-glucosidase
- acid alpha-glucosidase preproprotein
- acid maltase
- Aglucosidase alfa
- Alpha-1,4-glucosidase
- Amyloglucosidase
- Glucoamylase
- LYAG
- LYAG_HUMAN
- lysosomal alpha-glucosidase
Where can I find general information about genes?
The Handbook provides basic information about genetics in clear language.
These links provide additional genetics resources that may be useful.
What glossary definitions help with understanding GAA?
acids ;
amino acid ;
cell ;
digestive ;
enzyme ;
gene ;
glucose ;
glycogen ;
lysosome ;
molecule ;
mutation ;
protein ;
tissue
You may find definitions for these and many other terms in the Genetics Home Reference
Glossary.
The resources on this site should not be used as a substitute for
professional medical care or advice. Users seeking information about
a personal genetic disease, syndrome, or condition should consult with a qualified
healthcare professional.
See How can I find a genetics professional in my area? in the Handbook.
