Tay-Sachs disease (TSD) is a genetic disorder. It occurs when a fatty substance builds up in the brain. This causes progressive destruction of the brain. There are three forms:
Given the best of care, all children with the infantile form die by the age of five.
TSD is caused by the absence of an enzyme. This enzyme is needed to break down a fatty substance called ganglioside (GM2). As a result, GM2 builds up. The build up in the brain causes damage.
TSD occurs when both parents pass on the faulty genes. A person can have just one copy of the faulty gene. In this case, there are no symptoms. The person is called a carrier.
Factors that increase your chance for TSD include:
- Having parents who are carriers of the TSD gene
- Race: Eastern European (Ashkenazi) Jewish descent
- TSD is also frequently found in French Canadian and Cajun populations
Babies with TSD may seem to develop normally until about 4-5 months of age when symptoms begin to occur. Symptoms may include:
- Floppy body position
- Shrill cry
- Decreased eye contact
- Increased startle reaction
- Loss of motor skills
- Enlarged head
- Vision loss or blindness
- Difficulty swallowing
- Muscular difficulties such as spastic muscles, weakness, or paralysis
- Intellectual disability
In some cases, the symptoms do not begin until age 2-5 years old. The condition progresses slowly, but most children with Tay-Sachs disease do not live beyond age 15 years. Symptoms may include:
- Loss of the ability to speak
- Developmental delay and intellectual disability
- Loss of bowel control
- Sleep problems
- Movement disorder such as difficulty walking and muscle weakness
- Slurred speech
- Psychiatric problems
- Loss of vision
- Spasticity and seizures
The doctor will ask about your child's symptoms and medical history. A physical exam will be done. The doctor may examine your child's eyes to look for a cherry red spot on the retina.
Your child's bodily fluids may be tested. This can be done with blood tests.
There are no known ways to prevent Tay-Sachs disease. If you are a carrier of the gene that causes TSD, you can talk to a genetic counselor before deciding to have children. Prenatal testing during the first trimester is available.
- Reviewer: Kari Kassir, MD; Michael Woods, MD
- Review Date: 08/2013 -
- Update Date: 05/11/2013 -