What Is Tay-Sachs Disease

What is Tay-Sachs disease?

Tay-Sachs disease is a disease of the central nervous system. It is a genetic disorder meaning it can only be inherited and is almost always fatal. The disease appears in mostly babies but some people have experienced a late on set of the disease. In a healthy body enzymes clear out a fatty protein, called ganglioside, and unwanted substances so baby can develop vision, movement, hearing etc. A baby with Tay-Sachs disease is born without the enzyme called Hexosaminidase A (Hex A). Hex A is one of the enzymes that clear out the fatty proteins, but without it the fatty proteins build up in the nerve cells in the brain. In reaction to the build up the baby's hearing, sight, movement and mental development is affected. A relentless deterioration of mental and physical abilities will occur.

Tay-Sachs disease is an autosomal recessive genetic condition. A baby will only receive the disease if both parents are carriers of the gene. When two parents, that are carriers, have a baby there is:

Ð'* 50% chance that their child will be a carrier, but will not have the disease

Ð'* 25% chance that their child will not be a carrier and not have the disease

Ð'* 25% chance that their child will have the disease

Below there is a picture illustration of the recessive pattern.

Tay-Sachs comes in less common forms. There are other rare defects of the Hex A enzyme that are included under the Tay-Sachs name. The forms are known as juvenile, chronic and adult-onset forms. Instead of no amount of Hex A these individuals have low levels of the enzyme. Symptoms of the disease may occur later in their life and be much milder. The children with the juvenile Hex A develop signs of the disease by or around age two and death is around age fifteen. Those with chronic Hex A have signs of the disease around the age of five but the

symptoms are mild. Those with adult-onset Hex A experience their symptoms way later in life. Symptoms in all types are the same but not always as severe, that is how they are connected.

History of the Disease

Tay-Sachs disease was first noticed by Dr. Tay and Dr. Sachs, independently. Dr. Warren Tay was a British ophthalmologist. While caring for a patient he noticed a cherry-red spot on the retina of the patients eye. The red spot was common in babies with the problem. Dr. Bernard Sachs, a.k.a Barney, was an American neurologist. He saw the cellular and genetic changes, and the familial nature of the disease. He is responsible for recognizing and noting that the disease was common in babies of Eastern European Jewish origin. The disease was named after the two: Tay from Warren Tay and Sachs from Bernard Sachs.

Drs. Tay and Sachs were both describing the same disease but it wasn't until the 1930's when other physicians made the connection. The connection between the two observations was the Ganglioside. It had been the cause of neuron swelling later observed by Sachs and the red spot on the retinia observed by Tay.

Who has the Disease?

Tay-Sachs disease is common mostly among Jews of Eastern European origin. The disease was also found in French Canadians whose roots trace back to the St. Lawrence region, certain Cajuns in Louisiana, and some Amish communities. Many of the carriers are people in or of relation to the Ashkenazi Jews. One in thirty of this particular Jewish group is a carrier. The number or Jewish carriers is ten times more frequent than that of non-Jews. In general one in thirty-five thousand people are affected.

Getting Tested

Tay-Sachs disease can be diagnosed before and after birth. Or if you think you might be a carrier you can get screened. Before birth test called Amniocentesis and Chronic Villus Sampling (CVS) use different methods to find out if you baby has Tay-Sachs disease. Amniocentesis, usually done fifteen to eighteen months, is when a needle is inserted into the mother's abdomen and fluids are taken from the area surrounding the fetus. Those fluids are sampled for the presence of the Hex A enzyme, if it is not there then the baby has the disease. In CVS, usually done ten to twelve weeks, cells, identical to those of the fetus, are taken from the mother abdomen and are tested for the presence of the Hex A enzyme. People can also get screened to find out if they are carriers of the disease. This can be done simply by getting a blood test. This test measures the amount of hex A in the body. A carrier will have half the amount of the enzyme than noncarriers.

Treatment

For Tay-Sachs disease there is no treatment available. Children and babies with the disease are made as comfortable as possible. Medicines are prescribed to relieve pain, manage seizures, and control muscle spasticity. However research is ongoing. Researchers are finding out ways to treat the disease involving things like gene therapy and insulin injections. But still until a cure is found most of the affected children don't live past age five.

Personals

Many of babies around the world have had the displeasure to be affected with Tay-Sachs. It is sad to see that these children will never be able to have all the great opportunities that I have. Its even sadder when these babies never get a chance to even experience a little taste of life. They're just getting started when the basic skills they've just learned start to deteriorate. Some of the cases really popped out at me and I've decided to share what I've learned.

One beautiful baby girl from New Jersey had Tay-Sachs disease. She was born May 30, 1997. She had three siblings not at all affected. She loved animals and to watch Barney and Teletubbies. She died on March 17, 2001 at the age of five.