Tay-Sachs Disease

What is Tay-Sachs disease?

Tay-Sachs disease is a rare inherited disorder that progressively destroys the nerves in the brain and in the spinal cord. It is a type of lysosomal storage disease, and as it progresses, the child’s body loses function and cells and tissue are damaged.

What causes Tay-Sachs disease?

Tay-Sachs disease results when an enzyme that helps break down fatty substances, called gangliosides, is missing, which is caused by a mutation in the HEXA gene. As a result, these excess gangliosides build up to toxic levels in the brain, affecting the central nervous system, as well. This mutation is inherited in an autosomal recessive pattern.

What are the symptoms of Tay-Sachs disease?

In the most common form of Tay-Sachs disease, a baby will start to show symptoms at around six months of age. These include:

• Exaggerated startle response to sudden noises
• Listlessness
• Loss of previously acquired skills
• Diminished muscle tone (“floppy”)

As the disease progresses, and more and more cells die, children will have the following symptoms:

• Cherry-red spots in the middle layer of the eyes
• Gradual loss of vision
• Hearing loss
• Increased muscle stiffness and eventual paralysis
• Seizures
• Dementia

How is Tay-Sachs disease diagnosed?

A Tay-Sachs disease diagnosis may be made through a clinical evaluation and blood tests that measure the levels of the HEXA gene in the body. Sometimes, Tay-Sachs disease can be diagnosed before birth based on an amniocentesis and chorionic villus sampling (CVS).

What are the available treatments for Tay-Sachs disease?

There is currently no cure for Tay-Sachs disease, so treatment is currently symptomatic and supportive, such as anti-seizure medications, if necessary. However, gene therapy or enzyme replace therapy research may eventually lead to a cure or treatment that could slow the progression of the disease.

Where can I find more information on Tay-Sachs disease?

• Mayo Clinic
• National Organization for Rare Disorders (NORD)
• U.S. National Library of Medicine