Sandhoff disease

Autosomal recessive - en

Sandhoff disease is a rare, inherited lysosomal storage disorder that results from the deficiency of the enzyme beta-hexosaminidase. This enzyme deficiency leads to the accumulation of certain lipids, specifically GM2 ganglioside, in the neurons of the central nervous system. Sandhoff disease is one of the GM2 gangliosidoses, which also includes Tay-Sachs disease.

Genetics

Sandhoff disease is inherited in an autosomal recessive manner. This means that an individual must inherit two copies of the defective gene, one from each parent, to develop the disease. The gene responsible for Sandhoff disease is the HEXB gene, which encodes the beta subunit of the enzyme beta-hexosaminidase. Mutations in the HEXB gene disrupt the normal function of the enzyme, leading to the accumulation of GM2 ganglioside.

Symptoms

The symptoms of Sandhoff disease typically appear in infancy and progress rapidly. Common symptoms include:

• Muscle weakness
• Motor skill regression
• Seizures
• Vision loss
• Hearing loss
• Intellectual disability
• Cherry-red spot on the macula

Diagnosis

Diagnosis of Sandhoff disease involves a combination of clinical evaluation, family history, and specialized tests. These tests may include:

• Enzyme assay to measure beta-hexosaminidase activity
• Genetic testing to identify mutations in the HEXB gene
• MRI to detect brain abnormalities

Treatment

There is currently no cure for Sandhoff disease. Treatment is primarily supportive and focuses on managing symptoms and improving quality of life. This may include:

• Anticonvulsant medications for seizures
• Physical therapy to maintain mobility
• Occupational therapy to assist with daily activities
• Nutritional support to ensure adequate nutrition

Prognosis

The prognosis for individuals with Sandhoff disease is poor. Most affected children do not survive beyond early childhood due to the rapid progression of the disease and its complications.

Related Pages

• Tay-Sachs disease
• Lysosomal storage disorder
• GM2 gangliosidosis
• HEXB gene
• Autosomal recessive inheritance

See Also

• Genetic disorder
• Neurological disorder
• Inherited metabolic disorder