Overview

Carrier testing for Tay-Sachs disease allows people to find out if they have an increased chance of having a child with the disease. People who are carriers for a condition are healthy, but they have a higher chance of having a child who has the condition if their partner is also a carrier. Carrier testing is most often done by completing a genetic test that looks for changes in genes in a DNA sample from a person's cells.

Tay-Sachs is a rare disease that is passed down through some families. A person with Tay-Sachs has changes in a gene that keep the body from making any or enough of an enzyme that breaks down fatty compounds. Without it, fatty compounds build up in the brain and nerve cells and cause damage. Tay-Sachs is fatal. And there is no cure.

The choice to have the test for Tay-Sachs disease is a personal one. You may want to be tested if you are concerned that you or your partner might be carriers of Tay-Sachs. This is more likely if either of you has a family member who is a carrier or has the disease. If you and your partner are carriers, you could have a child who has Tay-Sachs, even though neither of you has the disease. You may choose to be tested if you are pregnant or thinking about becoming pregnant.

If both you and your partner are carriers, you may choose to test your pregnancy to see whether it is affected. The test results may affect your decision of whether or not to continue your pregnancy, or they can help you make choices about the care of your newborn child. Before you get tested, you should know what you will do with the results. To help with this, see a genetic counsellor before you make a choice about testing. The counsellor can explain the test and its results clearly. It can help you make good decisions.

Why would you have genetic testing for Tay-Sachs disease?

• You want to find out early if you are a carrier of the disease or if your unborn baby has the disease.
• You have a family history of the disease.
• Your partner has a family history of Tay-Sachs disease.
• You are from a high-risk group. These include:
  • People descended from eastern and central European Jewish communities (Ashkenazi Jews).
  • People with family from the Quebec Bas-St-Laurent or Gaspésie regions or New Brunswick territories.

What is genetic counselling?

Genetic counselling is guidance from someone who is trained to help you understand the risk of having a child with a genetic disease such as Tay-Sachs. You may talk about:

• How the disease is passed from parents to a child.
• The disease itself.
• Whether and how to test for the disease before getting pregnant or before a child is born.
• The chances that you will have a child with the disease. This will be based on your test results.
• What the results mean after the tests are done.