Tay-Sachs disease is a rare disorder passed from parents to child. It's caused by the absence of an enzyme that helps break down fatty substances. These fatty substances, called gangliosides, build up to toxic levels in the child's brain and affect the function of the nerve cells. As the disease progresses, the child loses muscle control. Eventually, this leads to blindness, paralysis and death.

If you have a family history of Tay-Sachs disease or if you're a member of a high-risk group and plan to have children, doctors strongly recommend genetic testing and genetic counseling.

In the most common form, an infant usually begins showing symptoms by about 6 months of age. Signs and symptoms of Tay-Sachs disease can include the following:

• Loss of motor skills, including turning over, crawling and sitting up
• Exaggerated reactions when the baby hears loud noises
• Seizures
• Vision and hearing loss
• "Cherry-red" spots in the eyes
• Muscle weakness
• Movement problems

When to see a doctor

If your child has any of the signs or symptoms listed above, schedule an appointment with your child's doctor.

Tay-Sachs disease is a genetic disorder that is passed from parents to their children. It occurs when a child inherits the gene from both parents.

Risk factors for Tay-Sachs disease include having ancestors from:

• Eastern and Central European Jewish communities (Ashkenazi Jews)
• Certain French Canadian communities in Quebec
• Old Order Amish community in Pennsylvania
• Cajun community of Louisiana

To confirm that your baby has Tay-Sachs disease, your doctor will ask you about the child's symptoms and any hereditary family disorders and will order a diagnostic blood test.

The blood test checks the levels of an enzyme called hexosaminidase in the child's blood. The levels are low or absent in Tay-Sachs disease.

While performing a careful eye exam of your child, the doctor may see a cherry-red spot in the back of the child's eyes, which is a sign of the disease. You may need to see a pediatric neurologist and an ophthalmologist for nervous system and eye examinations.

There is no cure for Tay-Sachs disease, but some treatments can help in managing symptoms. The goal of treatment is support and comfort. Supportive treatments include:

• Medication. To reduce your child's symptoms, a number of prescription medications are available, including anti-seizure medications.

• Respiratory care. Children who have Tay-Sachs disease are at high risk of lung infections that cause breathing problems and frequently accumulate mucus in their lungs.

  Your child may need the mucus using chest physiotherapy (CPT) to help remove mucus from the lungs.

• Feeding tubes. Your child may have trouble swallowing, or develop respiratory problems by inhaling food or liquid into the lungs while eating.

To prevent those problems, your doctor may recommend an assistive feeding device such as a gastrostomy tube, which is inserted through your child's nose and goes to your child's stomach. Or, a doctor trained in stomach surgery may surgically insert an esophagogastrostomy tube.

• Physical therapy. As the disease progresses, your child may benefit from physical therapy to help keep joints flexible and maintain as much ability to move (range of motion) as possible.

  Physical therapy can delay joint stiffness and reduce or delay the loss of function and pain that can result from shortened muscles.

Potential future treatments

Gene therapy or enzyme replacement therapy research may eventually lead to a cure or treatment to slow the progression of Tay-Sachs disease.

Ask your child's doctor to suggest resources and information to help you and your family cope with your child's needs. Look for local support groups to connect you with other families who are sharing similar challenges.