Ashkenazi Disorders: Mendelian

Tay-Sachs Disease

Tay-Sachs disease is the most familiar of the Jewish genetic disorders. Babies with Tay-Sachs disease are normal at birth. However, at 3-6 months of age, an affected baby will begin to lose developmental skills. Tay-Sachs disease is caused by a deficiency of an enzyme called hexosaminidase A or hex A. Lack of this enzyme affects the brain and the nervous system causing rapid and progressive deterioration. This condition is life shortening with death usually occurring by the age of 6. No effective treatment is available at this time. A late-onset form of Tay-Sachs also occurs, although it is rare.

Disease frequency:Potentially 1in 2,500 in the Jewish population. Frequency decreased through success of carrier screening programs.
Carrier frequency:1/26 – 1/30 in Jews, 1/300 in non-Jewish population.
Diagnosis:By measuring for deficiency of enzyme hex A in blood.
Inheritance:Autosomal Recessive
Carrier testing:By measuring for deficiency of hex A in blood and genetic testing of the Tay-Sachs gene.
Prenatal diagnosis:Possible by genetic testing of the Tay-Sachs gene or testing for deficiency of enzyme hex A.

Technical Information on Tay-Sachs Disease

Additional Information:
National Tay-Sachs and Allied Diseases Association
2001 Beacon Street, #204
Brighton, MA 02135
(800) 906-8723
fax: (617) 277-0134

Late-Onset Tay-Sachs Foundation
1303 Paper Mill Rd.
Erdenheim, PA 19038
(215) 836-9426
(800) 672-2022 (toll free)

Tay-Sachs and Allied Diseases Delaware Valley
101 Greenwood Avenue, Suite 570
Jenkintown, PA 19046
(215) 887-0877
fax: (215) 887-1931