Galactocerebrosidase

Identifiers
EC number	3.2.1.46
CAS number	9025-72-9
Alt. names
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway

Galactocerebrosidase is an enzyme that plays a crucial role in the metabolism of certain lipids in the body. It is responsible for the breakdown of galactocerebrosides, which are a type of glycosphingolipid found predominantly in the myelin sheath of nerve cells.

Function

Galactocerebrosidase catalyzes the hydrolysis of galactosylceramide into galactose and ceramide. This reaction is essential for the proper maintenance and turnover of myelin, the protective covering that surrounds nerve fibers in the central nervous system and peripheral nervous system.

Clinical significance

Deficiency in galactocerebrosidase activity leads to the accumulation of galactocerebrosides, which is associated with a rare genetic disorder known as Krabbe disease. This condition is characterized by severe neurological symptoms, including developmental delay, muscle weakness, and vision loss. Krabbe disease is an autosomal recessive disorder, meaning that an individual must inherit two defective copies of the GALC gene to manifest the disease.

Genetics

The GALC gene, located on chromosome 14 (14q31), encodes the galactocerebrosidase enzyme. Mutations in this gene can lead to reduced or absent enzyme activity, resulting in the symptoms observed in Krabbe disease. Genetic testing can identify mutations in the GALC gene, which is useful for diagnosis and carrier screening.

Diagnosis and treatment

Diagnosis of Krabbe disease typically involves measuring galactocerebrosidase activity in leukocytes or fibroblasts. Genetic testing can confirm the diagnosis by identifying mutations in the GALC gene. Currently, there is no cure for Krabbe disease, but treatment options such as hematopoietic stem cell transplantation may slow disease progression if administered early.

Research

Ongoing research is focused on developing gene therapy and other novel treatments for Krabbe disease. Animal models and clinical trials are being used to explore the potential of these therapies to restore normal enzyme function and improve patient outcomes.

See also

• Lysosomal storage disease
• Sphingolipidosis
• Enzyme replacement therapy