WHAT IS TAY-SACHS?
Tay-Sachs is a rare progressive neurological genetic disorder that is caused by the lack of the Hexosaminidase A enzyme which plays the important role of clearing away GM2 waste in the brain.
WHAT CAUSES TAY-SACHS?
Tay-Sachs sufferers have a mutation which means they don’t create enough (or any) Hexosaminidase A (Hex-A) enzyme. Hex-A's role is to break down GM2, which is a fatty acid. Hex-A is an enzyme that is created outside of a cell and absorbed into the cell. When the enzyme is mutated (like in TSD), the cell does not recognize it and quality control mechanism within the cell will not allow the mutated enzyme to be absorbed. The Hex A’s primary job is to break down waste inside a storage area in a cell. That storage area is called a lysosomal storage area and that is why Tay-Sachs is considered a Lysosomal Storage Disease (LSD).
The waste product is called GM2. It is basically a big complicated strand that is too big and long for a brain cell to deal with. The Hex-A breaks the GM2 down into little strands that can be used by the cell. When there is too-little Hex-A, the large GM2 strands begin to accumulate. As the waste accumulates the storage area begins to swell; it is the swelling that causes the cell to malfunction and eventually die.
Hex-A and GM2 are created in brain cells – that is why Tay-Sachs is primarily a neurological condition. The less Hex-A a person has the faster waste builds up.
THE VARIANTS OF TAY-SACHS
Children affected by the Infantile form generally have no Hex-A, Juvenile On-Set sufferers generally have little Hex-A, and finally Late On-Set victims have more Hex-A but not nearly enough to stop the progressive brain damage.
In Classic Infantile the destructive process begins in the fetus early in pregnancy, although the disease is not clinically apparent until the child is several months old. By the time a child with Tay-Sachs disease is between 18 month to 4 years old, the nervous system is so badly affected that life itself cannot be supported. Even with the best of care, all children with classic Tay-Sachs disease die early in childhood, usually by the age of 5, although some do live longer.
Children with Juvenile Tay-Sachs usually develop symptoms between the ages of 2 and 5 that resemble the symptoms of the Classic Infantile form. Though the course of the disease is slower, end stages generally occur in late adolescence or into the 20s. If starting after age 5, symptoms may be milder than those that characterize earlier onset forms. Mental abilities, vision and hearing remain intact, but affected individuals develop ataxia (lack of coordination), dysarthria (slurred speech), muscle atrophy (weakness), tremors and unsteady gait.
Late Onset or Chronic Tay-Sachs’ symptoms typically presents in adolescence, with dysarthria, proximal (trunk) muscle weakness, tremor and ataxia. Muscle cramps, especially in the legs at night, and fasciculations (muscle twitching) are common. Not all symptoms are present in every individual affected by the disease; weakness of the proximal muscles, however, is a symptom common to all. Examples of trunk muscle weakness may include difficulty rising from a seated position, trouble getting out of bed, struggling to balance while getting dressed.
Sadly, there is currently no cure for Tay-Sachs or its associated diseases. Children affected with Tay-Sachs have no hope unless we help raise funds to aid the research on the way. A cure for Tay-Sachs will also mean a cure for over 70 other Lysosomal Storage Diseases as well as other neurological conditions such as Parkinson’s, Alzheimer’s and Multiple-Sclerosis.