Ataxia Telangiectasia, or A-T, is a progressive, degenerative disease that affects many systems of the body. The first signs of disease usually appear in the second year of life -- usually a "wobbly" lack of balance and slurred speech. The onset of this ataxia (loss of muscle control) marks the beginning of progressive degeneration of the cerebellum. As the ataxia worsens A-T children lose their ability to write, and speech also becomes slowed and slurred. Even reading eventually becomes impossible as eye movements become difficult to control. Most A-T children are dependent on wheelchairs by the age of ten, not because their muscles are too weak, but because they cannot control them. Later, A-T patients usually die from respiratory failure or cancer by their teens or early twenties.
Epidemiologists estimate the frequency of A-T as a range from 1 in 40,000 births to 1 in 100,000 births. But it is believed that many A-T children, particularly those who die at a young age, are never properly diagnosed. Therefore, this disease may actually be much more common. The disease appears to cross all racial, economic, geographic or education categories. Both males and females are equally affected.