This approach holds great promise for future Tay-Sachs patients.Ī simple blood test can identify Tay-Sachs carriers. Another avenue of research is gene therapy in which scientists transfer a normal gene into cells to replace an abnormal gene. Bone marrow transplantation has been attempted also, but to date has not been successful in reversing or slowing damage to the central nervous system in babies with Tay-Sachs. Scientists are exploring enzyme replacement therapy to provide the Hex-A that is lacking in babies with Tay-Sachs. However, researchers are pursuing several approaches to finding a cure. There is no cure or effective treatment for Tay-Sachs disease. For the general population, about one in 250 people are carriers. Lawrence River and in the Cajun community of Louisiana also have a higher incidence of Tay-Sachs. Non-Jewish French Canadians living near the St. Approximately one in every 27 Jews in the United States is a carrier of the Tay-Sachs disease gene. While anyone can be a carrier of Tay-Sachs, the incidence of the disease is significantly higher among people of eastern European (Ashkenazi) Jewish descent. When both parents are carriers of the defective Tay-Sachs gene, each child has a 25 percent chance of having Tay-Sachs disease and a 50 percent chance of being a carrier.Įastern European (Ashkenazi) Jews at Greater Risk for Tay-Sachs Disease: If both parents are carriers and their child inherits the defective Hex-A gene from each of them, the child will have Tay-Sachs disease. A child who inherits one inactive gene is a Tay-Sachs carrier like the parent. They do not have Tay-Sachs disease but they may pass on the faulty gene to their children.Ĭarriers have a 50 percent chance of passing on the defective gene to their children. Carriers of Tay-Sachs - people who have one copy of the inactive gene along with one copy of the active gene - are healthy. If either or both Hex-A genes are active, the body produces enough of the enzyme to prevent the abnormal build-up of the GM2 ganglioside lipid. Tay-Sachs disease results from defects in a gene on chromosome 15 that codes for production of the enzyme Hex-A. Treatment involves managing the symptoms of the disease. As for the childhood form of Tay-Sachs, there is no cure. Only recently identified, the disease has not been extensively described. By the time a child with Tay-Sachs is three or four years old, the nervous system is so badly affected that death usually results by age five.Ī much rarer form of Tay-Sachs, Late-Onset Tay-Sachs disease, affects adults and causes neurological and intellectual impairment. Eventually, the child becomes blind, cognitively impaired, paralyzed and non-responsive. The infant gradually regresses, and is eventually unable to crawl, turn over, sit or reach out. By about two years of age, most children experience recurrent seizures and diminishing mental function. However, a baby with Tay-Sachs disease appears normal until about six months of age when its development slows. In children, the destructive process begins in the fetus early in pregnancy. This ongoing accumulation causes progressive damage to the cells. Without Hex-A, a fatty substance, or lipid, called GM2 ganglioside accumulates abnormally in cells, especially in the nerve cells of the brain. Tay-Sachs is caused by the absence of a vital enzyme called hexosaminidase-A (Hex-A). Tay-Sachs disease (TSD) is a fatal genetic disorder, most commonly occurring in children, that results in progressive destruction of the nervous system.

What chromosome is SCIDS on