Tay-Sachs Disease: Beyond Prevention and Toward Treatment
Posted Nov 19 2009 10:02pm
In an earlier post, I talked about Ashkenazi Jewish diseases in general. Now let’s turn to one disease in particular, Tay-Sachs, which is a disease that sadly claims the lives of children under the age of 5.
Tay-Sachs more frequently arises in children with Ashkenazi Jewish ancestry because of the increased likelihood of people in this population to be carriers. Within the general population, only 1 in 300 people are carriers of Tay-Sachs disease, while within the Ashkenazi Jewish population, 1 in 30 people are carriers.
Though it is not curable, Tay-Sachs is preventable through carrier testing when a couple is planning a pregnancy. The Center for Jewish Genetic Diseases reports: “almost 1,100 carrier couples have been identified and counseled as to their 25% chance to have an affected child. Since prenatal diagnosis for this disease is available and quite reliable, these couples have the option to have unaffected children.” This type of testing and caution can help reduce the number of children and families who must suffer through this painful disease.
In the most common form of Tay-Sachs disease, symptoms begin to develop in the first six months of an infant’s life. These symptoms include neurological degeneration and deterioration of physical abilities (including blindness and deafness). This degeneration results from the accumulation of harmful quantities of fatty acids in the nerve cells in the brain.
Anyone can determine if they are a Tay-Sachs carrier by taking a carrier screening test. These simple blood tests can detect levels of hexosaminidase A activity, which is the enzyme responsible for the degradation of fatty acids. This enzyme is encoded by the HEXA gene – and HEXA gene changes result in ineffective hex A enzyme.
Beyond prevention, new experimental treatment options are available for some children who are living with the disease. Benjy Margulies, a 2 year old living with Tay-Sachs, is currently undergoing therapy after a cord blood transplant, and so far has been successfully battling back against the disease. His parents keep a blog about their young hero. Benjy was in the news last summer because of his parents’ long battle to convince their insurance provider, Aetna, to continue paying for Benjy’s treatment.
The cord blood transplant that Benjy received is one of several possible experimental treatments for Tay-Sachs disease. The March of Dimes has reported that cord blood transplants hold exciting promise, but they are a treatment that is still largely investigational. Other experimental treatments under research include enzyme replacement therapy, gene therapy, and etabolic therapy. We will keep our fingers crossed for Benjy and for these new possible treatments.