Definition:
Late infantile/Juvenile/GM1 Gangliosidosis is caused by a deficiency in the enzyme acid beta-galactosidase-1 and results in the accumulation of ganglioside in the tissues. This disorder affects the cells of the central and peripheral nervous systems, particularly the nerve cells. 

Symptoms:
Symptoms of late infantile GM1 Gangliosidosis commonly occur between the ages of one and three years. Affected children develop neorological symptoms such as ataxia, seizures, dementia, and speech difficulties.

Inheritance Patterns:
GM1 Gangliosidosis is an autosomal recessive disorder.

Diagnosis and Testing:
An enzyme assay using blood or skin specimens is performed to confirm a diagnosis of GM1 Gangliosidosis. This test measures the amount of the enzyme acid beta-galactosidase-1 and compares it to normal enzyme activity levels. If this disorder is present, low levels of this enzyme will be present.

Life Expectancy
Many children with late infantile GM1 Gangliosidosis survive until teenage years.

Treatment:
Bone marrow transplants have been met with limited success in reducing the progression of the disorder, but no long-term benefits were seen. Palliative treatment has been used to reduce some of the neurologic symptoms associated with this disorder. Gene therapy and enzyme replacement therapy are two treatments that are currently under investigation as a hope to cure GM1 Gangliosidosis.

Patient Groups:
National Tay-Sachs & Allied Diseases Association
2001 Beacon Street, Suite 204
Boston, MA 02135
www.ntsad.org
tel: (800) 906-8723
fax: (617) 277-0134
Sue R. Kahn, Executive Director
info@ntsad.org