Tay-Sachs disease is a rare central nervous system disorder in which symptoms typically begin in infancy. This disease can be found throughout the world but is most prevalent in people of Ashkenazi Jewish heritage.
While this condition is rare, it does affect certain groups of people at a higher rate than others.
Here’s more about what causes Tay-Sachs disease, how common this disease is worldwide, and what the outlook is for people who have it.
Researchers say that around
People may also be carriers of the disease. This means that they do not have the disease, but they carry the genetic information to pass it on to their children at conception.
Experts estimate that across the globe, around 1 in 200,000 babies are born with Tay-Sachs disease. However, as in the United States, Tay-Sachs is more common in certain countries or populations than others.
Tay-Sachs is a genetic disease that is inherited in an autosomal recessive manner. This means that a child must inherit two affected hexosaminidase-A genes — one from each parent — in order to develop the disease.
In fact, the main risk factor for developing the disease is having biological parents who are both carriers. If two carriers have a child, there is a 1 in 4 chance the child will develop the disease and a 2 in 4 chance the child will be a carrier.
Here’s a breakdown of the inheritance scenarios:
- Only one parent passes down the affected gene: The child will be a carrier.
- Both parents pass down affected genes: The child will have Tay-Sachs.
- Both parents pass down unaffected genes: The child will not be affected.
There’s no cure for Tay-Sachs disease. Treatment may slow the progression of the condition and improve a child’s quality of life. Complications and life expectancy depend on the onset of the disease and what type a person has.
Researchers are currently working on treatments, like enzyme replacement therapy, with the hope of improving symptoms and extending life.
Where is Tay-Sachs disease most common?
Regions in North America with the highest
- Southwest Louisiana, U.S. (Cajun population)
- Pennsylvania, U.S. (Amish)
- Southeast Quebec, Canada (French-Canadians)
Globally, the groups most affected by Tay-Sachs disease are populations that originated in Central and Eastern Europe.
Is Tay-Sachs a rare disease?
What are the odds of passing Tay-Sachs disease to your children?
If both biological parents are carriers of the affected gene, there’s a 25% chance their child will develop Tay-Sachs. There’s a 50% chance their child will be a carrier and a 25% chance their child will be unaffected.
Make an appointment with your doctor if you suspect you or your partner might be a carrier of an affected gene. You can learn your status by having a simple blood test. If you’re already pregnant, genetic testing is another option.
Remember: A child must inherit two affected genes to develop Tay-Sachs. Your doctor can go over your risks and, if necessary, discuss alternative modes of reproduction, like in-vitro fertilization, using donor eggs or sperm, or adoption.