Because of better pre-natal testing for parents and a more thorough knowledge of this disease, Tay Sachs is not as common as it used to be. And this is a good thing, because it its most common form, it attacks infants in their first year of life and is always fatal. Read on to find out more about this serious condition.
What is Tay Sachs Disease?
Tay Sachs is a rare but very serious genetic condition which is passed down from parents to their children. It comes in two forms – Infantile (or Classic) and Late Onset. Unfortunately, the Infantile Form is the most common for this disease and also the most severe. Because the Late Onset Tay Sachs is so rare, this article will deal with the Classic Tay Sachs only.
What Causes Tay Sachs?
Both kinds of Tay Sachs Disease are caused by changes in genes called genetic mutations. In this case, the mutation happens on the HEXA gene. This mutation means that the body cannot make a certain enzyme used by the lysomes in the cells to detoxify and recycle certain materials. This means that toxins can build up in the body and eventually will attack the neurons (nerve cells) in the brain and spinal cord. It’s these attacks that lead to many of the signs and symptoms of this disease.
This disease is autosomal recessive which means that both a baby’s mother and father have to have this genetic mutation in order for the baby to get the disease.
What are the Signs and Symptoms of Tay Sachs?
In Infantile Tay Sachs Disease, the first signs and symptoms will begin to appear around 3-6 months of age. Though they can sometimes start out mild, they will get worse as the disease progresses. These symptoms include:
- Slowed development
- Losing skills the baby previously mastered (such as the ability to roll over)
- Loss of other motor skills and increasing muscle weakness
- Severe reactions to loud noises in the environment
As the disease progresses, symptoms will also include:
- Decreased vision and the appearance of “cherry red spots” on the eyes
- Loss of hearing
- Mental retardation/intellectual disability
Who is at Risk for Tay Sachs Disease?
The good news is that this disease is almost entirely limited to certain ethnic groups around the world. The most common is Ashkenazi Jews (Jews from Eastern or Northern Europe). However, other groups have also been found to be carriers for this mutation, including those among the Amish in Pennsylvania, Cajuns in Louisiana and French Canadians in Quebec.
To give an idea of how common this is, it is estimated that 1 in every 25 to 35 Ashkenazi Jews is a carrier for Tay Sachs, while in non-Jewish populations it is more like 1 in every 700. This disease is believed to affect 1 in every 3,900 Jewish birth (compare this to 1 in 112,000 births in the general population).
How is Tay Sachs Diagnosed?
There are several ways that Tay Sachs can be diagnosed, apart from clinical exam and reports of signs and symptoms:
- A baby can be diagnosed before it is ever born through tests known as amniocentesis or chorionic villus sampling, which study samples of blood and amniotic fluid (the fluid that a baby floats in while still in the uterus) to see if a disease is present.
- A baby can be diagnosed after birth by doing blood work like looking at levels of certain enzymes in the blood.
How is Tay Sachs Treated?
Sadly, there is no cure for Tay Sachs disease and it is always fatal, usually before a child’s 3-5th birthday. Treatment for it centers on things like using medications to stop seizures, therapy to help a child retain their motor skills for as long as possible and measures to keep a child as comfortable as possible.
However, research is underway on gene therapy and researchers are hopeful that with continued work, there might be a way to slow down this disease – or even to cure it – in the future. That is why preventing it in the first place is so important?
How Can You Prevent Tay Sachs Disease?
If parents are from the ethnic groups mentioned above, getting genetic counselling before getting pregnant is very important. This counselling will take blood work from both parents and test them for the gene that causes Tay Sachs. If just one parent has this gene, it is ok to start a family since the baby cannot be born with this disease. However, if both parents have the mutation, a discussion should be had about alternate methods of having a family, such as adoption.
In short, Tay Sachs Disease is a serious condition and its most common form strikes early on in life and is always fatal. However, research is underway to use genetics to slow down or possibly cure this disease and with genetic counselling of parents from certain ethnic groups, this disease can be avoided altogether.