Tay-Sachs Disease-Topic Overview
Tay-Sachs Disease-Topic Overview
Tay-Sachs Disease Guide
Tay-Sachs is a rare disease that is passed down through some families. A person with Tay-Sachs has changed (mutated) genes that don't make any or enough of an enzyme called hexosaminidase A (hex A). Hex A breaks down fatty compounds. Without it, fatty compounds build up in the nerve cells of the brain and cause damage.
There are two forms of Tay-Sachs:
Tay-Sachs can occur when parents pass on a changed gene to their child.
In late-onset Tay-Sachs (LOTS), the body makes a small amount of hex A. People with LOTS inherit the late-onset hex A gene change from one or both parents.
The changed gene that causes Tay-Sachs disease is more commonly found in people of Ashkenazi Jewish descent. About 1 out of 30 people in this population is a carrier of the disease.1 People of French-Canadian descent from the East Saint Lawrence River Valley of Quebec and people of Cajun descent in Louisiana are also more likely than others to carry the changed gene.
Tay-Sachs Disease - Topic Overview
Tay-Sachs Disease Guide
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What is Tay-Sachs disease?
Tay-Sachs is a rare disease that is passed down through some families. A person with Tay-Sachs has changed (mutated) genes that don't make any or enough of an enzyme called hexosaminidase A (hex A). Hex A breaks down fatty compounds. Without it, fatty compounds build up in the nerve cells of the brain and cause damage.
There are two forms of Tay-Sachs:
- The most common form develops soon after a baby is born. It causes death early in childhood.
- Late-onset Tay-Sachs can start between puberty and the mid-30s. How long a person lives depends on how severe the symptoms are. People may live as long as someone who doesn't have Tay-Sachs disease. Late-onset Tay-Sachs is very rare.
What causes Tay-Sachs disease?
Tay-Sachs can occur when parents pass on a changed gene to their child.
- If a baby gets the changed gene from both parents, he or she will get the disease.
- If the baby gets the changed gene from only one parent, he or she will be a carrier. This means that the child will have one gene that produces hex A and one that doesn't. The child's body makes enough hex A so that he or she doesn't get the disease. But the child can pass the changed gene on to his or her children.
In late-onset Tay-Sachs (LOTS), the body makes a small amount of hex A. People with LOTS inherit the late-onset hex A gene change from one or both parents.
The changed gene that causes Tay-Sachs disease is more commonly found in people of Ashkenazi Jewish descent. About 1 out of 30 people in this population is a carrier of the disease.1 People of French-Canadian descent from the East Saint Lawrence River Valley of Quebec and people of Cajun descent in Louisiana are also more likely than others to carry the changed gene.
