Tay-Sachs Disease
What is Tay-Sachs disease?
Tay-Sachs disease is a rare inherited disorder that causes progressive destruction of nerve cells in the brain and spinal cord (the central nervous system).
The most common form of Tay-Sachs disease begins in infancy. Infants with this disorder typically appear normal until the age of 3 to 6 months, when development slows and muscles used for movement weaken. Affected infants lose motor skills such as turning over, sitting, and crawling. They also develop an exaggerated startle reaction to loud noises. As the disease progresses, children with Tay-Sachs disease experience seizures, vision and hearing loss, mental retardation, and paralysis. An eye abnormality called a cherry-red spot, which can be identified with an eye examination, is characteristic of this disorder. Children with this severe infantile form of Tay-Sachs disease usually survive only into early childhood.
Other forms of Tay-Sachs disease are much rarer. Signs and symptoms can begin in childhood, adolescence, or adulthood and are usually milder than those seen with the infantile form of Tay-Sachs disease. As in the infantile form, mental abilities and coordination are affected. Characteristic features include muscle weakness, loss of muscle coordination (ataxia) and other problems with movement, speech problems, and mental illness. These signs and symptoms vary widely among people with late-onset forms of Tay-Sachs disease.
How common is Tay-Sachs disease?
Tay-Sachs disease is very rare in the general population. The genetic mutations that cause this disease are more common in people of Ashkenazi (eastern and central European) Jewish heritage than in those with other backgrounds. In recent years, however, screening for mutations and genetic counseling have made the condition much less frequent in this population.
What other names do people use for Tay-Sachs disease?
- B variant GM2 gangliosidosis
- GM2 gangliosidosis, type 1
- HexA deficiency
- Hexosaminidase A deficiency
- Hexosaminidase alpha-subunit deficiency (variant B)
- Sphingolipidosis, Tay-Sachs
- TSD
Credit: National Institute of Health.